Semi-solid Heat Treatment of Hypereutectic Al-18% Si Alloy Containing Iron-rich Intermetallics
The Biological Chemistry of Iron · to iron-containing systems. This volume contains an excellent...
Transcript of The Biological Chemistry of Iron · to iron-containing systems. This volume contains an excellent...
The Biological Chemistry of Iron
A Look at the Metabolism of Iron
and Its Subsequent Uses in Living Organisms
Proceedings of the NATO Advanced Study Institute held at Edmonton, Alberta, Canada, August 23 - September 4,1981
edited by
H.BRIAN DUNFORD Dept. of Chemistry, University of Alberta, Edmonton, Canada
DAVID DOLPHIN Dept. of Chemistry, University of British Columbia, Vancouver, Canada
KENNETH N. RAYMOND Dept. of Chemistry, University of California, Berkeley, U.S.A. and
LARRY SIEKER Dept. of Molecular Structure, University of Washington, Seattle, U.S.A.
D. Reidel Publishing Company
Dordrecht Holland / Boston .U.S.A. / London England
Published in cooperation with NATO Scientific Affairs Division
PREFACE
The results of a NATO Advanced Study Institute (ASI) entitled "Coordination Chemistry Environments in Iron-Containing Proteins and Enzymes - Including Smaller Molecules and Model Systems" are summarized in this book. The ASI was held in the Province of Alberta, Canada, from August 23 to September 4, 1981. The first half of the conference was held on the campus of the University of Alberta, Edmonton, and the second half at the Overlander Lodge, Hinton.
Two other conferences had the greatest impact upon the planning for this ASI. One was a NATO ASI held in Tomar, Portugal in September of 1979, entitled "Metal Ions in Biology". Among the organizers for that conference were Allen Hill and Antonio Xavier; we are happy to acknowledge their beneficial influence on our subsequent conference. The other most influential conference was one organized by Ralph Wilkins and Dennis Darnell entitled "Methods for Determining Metal Ion Environments in Proteins" which was held in Las Cruces, New Mexico, U.S.A., January 10-12, 1979. The Las Cruces conference invited lectures were published as Volume 2 of "Advances in Inorganic Biochemistry", G. Eichhorn and L. Marzilli, editors. Most of the physical techniques used to probe metal ion environments are eloquently described in the latter volume. The undersigned organizers for the Alberta ASI made two decisions which shaped its format: first, to narrow the scope of "Metal Ions in Biology" to iron-containing systems. Second, to emphasize a description of the results obtained by investigation of the biological systems, and not the physical techniques used to probe the systems. One exception is Mossbauer spectroscopy, a technique not described in the proceedings of the Las Cruces conference, which is uniquely suited to iron-containing systems. This volume contains an excellent description of both the technique and the type of results which can be obtained from it.
The title of this book "The Biological Chemistry of Iron" is simplicity itself. It also is misleading, because justice to the title would require a monumental multivolume series. Nevertheless, we have used it for the sake of brevity. To the best of our knowledge this volume is the first to attempt to describe in some detail both sides of the story of the biology of iron. One side is the gathering of iron, its storage and transport, in other words the metabolism of iron. The other is the utilization of the iron by living systems. Most animal systems use most of their iron to transport or store oxygen. Myoglobin and hemoglobin immediately come to mind. However, these molecules have been intensively studied and well described elsewhere (see for example "Hemoglobin and Myoglobin in their Reactions with Ligands" by E. Antonini and M. Brunori, North-Holland, Amsterdam - a book which is still of great value although it was published in 1971. We do not mean to imply that research on these molecules is anywhere near complete.) There are many references to hemoglobin in this volume, but we describe in detail a less well-known oxygen transport molecule, hemerythrin. Another well known heme protein, cytochrome o is discussed briefly, but we have concentrated more on the remarkable four-heme molecule cytochrome £3. With these types of decisions the conference was held to a viable two week format.
Most of our interest centered on iron-containing enzymes and model systems, as essential for aerobic life as oxygen transport. It would appear that we may be approaching the point where we have enough structural and mechanistic information to elucidate completely the mechanism of an enzyme reaction. One may judge for oneself how well the criteria of complete mechanistic information as defined by biologists, chemists and/or physicists are being met for the enzymes discussed in this volume. Many important iron enzymes are not discussed; it was our concern to obtain some depth for which we paid a price in breadth of coverage.
The participants at the conference ranged from graduate students to senior investigators, from theoretical chemists to medical doctors, from microbiologists to physicists. The mix of participants was truly interdisciplinary providing an accurate match to the types of research required to push back the research frontier on the biological chemistry of iron.
This book is organized in sections which we describe briefly. Speakers (as distinct from coauthors) are also listed. Section A, the introduction, contains the keynote lecture by Allen Hill. It also contains two lectures which were organized as an "inorganic chemistry teach-in" to review the basic principles of inorganic and physical chemistry which must apply equally to non-biological and biological iron. The first, by Ralph Wilkins, describes ligand reaction dynamics. The second, by Chris Reed, discusses the influence of structure, spin state, ligand equilibria, coordination number, redox potential and oxidation state. The remainder of the book might be summarized as follows. It is concerned with the elucidation of ways in which the biological
environment and the iron (or in a few cases, copper or molybdenum) influence each other according to the basic principles of physics and chemistry. Iron metabolism is summarized in Section B. Robert Crichton describes the iron storage protein, ferritin. The iron transport protein, transferrin, is the topic of Philip Aisen. Ken Raymond and Gunther Winkelmann discuss those unique iron-grabbers for microorganisms, the siderophores, as well as the chemistry of analogous molecules. And last, but not least, Rowe Byers describes iron uptake and distribution in cultured beating heart muscle cells.
Section C is for cytochromes, particularly as viewed using NMR spectroscopy. These are the topic of Antonio Xavier. In Section D, the topic is the oxygen transport molecule, heme-rythrin; the dynamics and mechanisms of its reactions (Ralph Wilkins) and its three-dimensional structure (Larry Sieker and Ron Stenkamp).
The topic of Section E is iron-sulfur centers, clusters and enzymes. We are indebted to Jose Moura for coordinating this section. Jose also gave the introductory talk. Hydro-genases and nitrogenases are described in detail: hydrogenases by Hans Grande and Jean LeGall and nitrogenases by Gees Veeger and Vincent Huynh. In the latter talk, Mossbauer spectroscopy is described.
Section F is for ferrous and ferric hemes. Heme model studies are documented. Magnetic complexities in hemes (Robert Scheldt), resonance energies (Philip George), models for peroxidases and cytochrome P-450 (David Dolphin), theoretical calculations on model cytochrome P-450 (Gilda Loew) and hemes of hydroporphyrins (Chris Chang) provide an excellent background for a look at the heme-containing enzymes themselves.
In the final part, Section G, heme enzymes are the topic. An introduction to the peroxidases is provided by Brian Dunford, Rick Rutter, Ron Wever and Nils Ellfolk. The nature of the ligand in the fifth coordination position of the heme iron of horseradish peroxidase is scrutinized intensively by Gerd LaMar and Teizo Kitagawa, as is Compound I of horseradish and yeast cytochrome o peroxidases by Brian Hoffman. Cytochrome P-450 is the topic for Gerald Wagner and Volker Ullrich. With increasing enzyme complexity, catalase is introduced by Peter Jones. The three-dimensional structure of beef liver catalase is outlined by Nobuo Tanaka and Thomas Reid III. Finally the pi.'ece de resistance of heme enzymes, cytochrome o oxidase is reached. Its subunits (Howard Mason) and EXAFS structural results on its copper (Robert Scott) are the aspects treated here.
Philip George was honorary chairman for the conference. He was the hardest working honorary chairman any of us have seen. Not only did he act as chairman for events, both scientific and social, but he is a contributor to this volume. Our hats are off to you, Philip. The only criticism we can make of your pioneering research is that it was ahead of its time.
Acknowledgements are in order to the following organizations and persons: to the University of Alberta and the Overlander Lodge for providing first-rate conference facilities. In particular we thank Therese Roberts and her helpers at Lister Hall; Stockwell Day, his family and his staff at the Overlander Lodge. The grant from NATO Scientific Affairs Division made the conference possible. In addition, the financial help of the Alberta Heritage Foundation for Medical Research is gratefully acknowledged as well as that from the Natural Sciences and Engineering Research Council of Canada, an anonymous donor and Smith-Klein Pharmaceutical. Social events sponsored by the City of Edmonton Business Development Office, (thank you Al Bleiken and Paul Ouimet) and a hospitality grant from the Province of Alberta contributed in a large way to the success of the conference. A large fraction of this volume was typed in camera-ready form by Lavine Shupenia and Jacki Jorgensen; they now will have an audience of appropriate size to view their handiwork. Special thanks go to Jacki Jorgensen and Dee Dunford who looked after many of the local arrangements.
The Editors: Brian Dunford, Edmonton, Alberta David Dolphin, Vancouver, British Columbia Kenneth Raymond, Berkeley, California Larry Sieker, Seattle, Washington
Ahr, H.J. 413
Aisen, P. 63
Araiso, T. 337
Boelens, R. 337
Braaksma, A. 223
Byers, B.R. 117
Castle, L. 413
Chang, C.K. 313
Chacko, V.P. 357
Cox, P. 117
Crichton, R.R. 45
deRopp, J.S. 357
Dolphin, D. 283
Dunford, H.B. 337
Dunham, W.R. 193
Ellfolk, N. 337
George, P. 273
Grande, H.J. 193,223
Gunsalus, I.C. 405
Haaker, H. 223
Hager, L.P. 337
Harrington, P.C. 145
Hill, H.A.O. 3
Hoffman, B.M. 391
Huynh, B.H. 241
Jensen, L.H. 161
Job, D. 337
Jones, P. 427
Kast, W.M. 337
Kitagawa, T. 375
Kuthan, H. 413
Laane, C. 223
LaMar, G.N. 357
LeGall, J. 207
Loew, G. 295
Mason, H.S. 459
Moura, I. 127,179
Moura, J.J.G. 127,179
Mu'nck, E. 241
Murthy, M.R.N. 439
Nastainczyk, W. 413
Orme-Johnson, W.H. 241
Peck, H.D., Jr. 207
Pudzianowski, A. 295
Raymond, K.N. 85
Reed, C.A. 25
Reid, T.J., III 439
Ricard, J. 337
Robinson, P. 117
Ronnberg, M. 337
Rossmann, M.G. 439
Ruf, H.H. 413
Rutter, R. 337
Santos, M.H. 127
Scheldt, W.R. 261
Sciortino, C.V. 117
Scott, R.A. 475
Sicignano, A. 439
Sieker, L.C. 161
Spangler, D. 295
Stenkamp, R.E. 161
Tanaka, N. 439
Teraoka, J. 375
Tufano, T.P. 85
Ullrich, V. 413
van Dijk, C. 193
Veeger, C. 193,223
Villalain, J. 127
Wagner, G. C 405
Wever, R. 337
Wilkins, R. G. 13, 145
Winkelmann, G. 107
Xavier, A.V. 127
SUBJECT INDEX
apoferritin, analogies with lactate
dehydrogenase 54 electron microscopy
of 53 structure of 48
apoprotein formation 18 aqueous chemistry of iron 63 aromatic nitrogen hetero-
cycles 276 aromaticity of porphyrin
ring 339 Asoomyoetes fungi 107 assembly of cytochrome o
oxidase 459 associative mechanism 14 ATP production,
chemiosmotic model for 65 autoxidation, of
Fe(II) 64 in Thiobaoillus fevvi-
oxidans 65 hemerythrin 152 A. vinelandii ferreoxin 185,189 A. vinelandii nitro-
genase 223 axial ligands, 36
of cytochrome P-450 407 in heme complexes 261 strong field 262
axial ligation, of heme iron 377 influence on Raman
frequencies 381 P and s bonds in 377
azurin, reduction of cytochrome o perox- idase with 351
Ab initio calculations, of resonance energies 278
aconitase, 3Fe-3S centers in 187
active site, of peroxidases, ionizable
groups in 341,348 aerobactin 94,122 aerobic life, key to 459 agrobactin 117,121 alcohols,
from cellulose degrada- tion 208
amino acid sequence, of ferritin 48 of transferrin 69
amino acid substitutions, in cytochromes 134
ammonia, as inhibitor of N2 fixa- tion 227
analytical gel electro- phoresis ,
of cytochrome c oxidase 469 Swank-Munkres procedure for 469
anemia, 46 (see also Cooleys1 anemia)
antiferromagnetic coupling, 27 between metal ions 39
antimicrobial activity, of myeloperoxidase 347
antitumor activity, of bleomycin 66
2A1u and 2A2u orbitals, of porphyrins 385 in chloroperoxidase 334
rate, constants for binding by hemes 318 titration, of cyto- chrome c peroxidase 350
carbonmonoxyhemoglobin 27 carbon tetrachloride
reaction with cyto- chrome P-450 416
carbonyl compound of iron in (-11) oxidation
state 26 catecholate,
iron exchange rates with 103 reaction with ferric ion 86 siderophores 86
cation radical (see also TT
cation radical) in peroxidase compound I 29
catalase, 284 biliverdin complex in 440 catalatic activity of 440 compound I of 428,432 crystal structure of 428,439 description of molecule 441 electron density map for 452 erythrocyte 440 general properties of 430 heavy atom derivatives of 448 heme environment 449
essential residues in 453 heme pocket in 454 hydrogen bonding in 442 iron-porphyrin models for 427,433 kinetics of action of 431 organization of molecule 441 from V e n i o i t t i y m v i t a t e 441,447 peroxidatic activity of 440 proximal phenoxide in 286 quaternary structure in 449 reaction with hydrogen
peroxide 391,427 role of iron coordination
environment in 427 role of protein in 435 secondary structure in 444 subunits of 440 tyrosyl l igand in 439
bacterial ferredoxin 33 bacterial growth, regulation
in oral cavity 347 B as id i o my oe t es fungi 107 beef liver catalase (see also
catalase) structure of 439
binding constants, of CO by hemes 318 of iron by siderophores 94,102
binuclear iron complex in hemerythrin 161,165
bioenergetics of proton pumping 475
biological probes, chromic siderophores as 88
biosynthesis of cytochrome o oxidase 459
bleomycin, antitumor activity of 66
blood transfusion, excess iron from 46
bond lengths, iron-sulfur, in cyto- chromes 133 bonellin,
structure of 314 B . p o l y m i x a ferredoxin 188 bromination reactions of
chloroperoxidase 34>
calcium ions, in horseradish peroxi- dase 339 C a l da r i o my o es fumago,
chloroperoxidase from 343 camphor monoxygenase
cytochrome P-450 as 405 carbanions and carbenes,
from cytochrome P-450 reactions 413
carbon monoxide, binding constants by
hemes 318 binding by hydro-
porphyrins 317 complex, of reduced
cytochrome P-450 406
catalatic action of iron(III) porphyrin
models 433 of catalases 427,440 of chloroperoxidase 343,440
influence of iron coordina- tion on 429 CD spectra (see circular
dichroism spectra) cellular iron metabolism,
model systems for 118 cellulose degradation 207 ceruloplasmin 65 chain reactions catalyzed
by ferrous ion 429 Chang cells,
iron metabolism in 118 chelating agents, 18
for iron overload 85 effect on iron uptake and distribution 121 chelation therapy,
for iron overload 103 chemiosmotic model,
for ATP production 65 chlorination reactions,
of chloroperoxidase 343 chlorins,
iron 313 redox potentials of 325
chloroperoxidase, Ai u and A2 U orbitals in 334 bromination reactions of 343 from C a l d av i o my c es
f i ma go 343 catalatic reaction of 343,440 chlorination reactions of 343 compound I,
comparison to horse- radish peroxidase 334 EPR spectrum of 345 Mossbauer spectrum of 345 coordination reactions
of 343 organic substrate halo- genation by 343 similarities to cyto- chrome P-450 344
C h r o m a t i u m HiPIP 187 chromic,
desferriferrichrome 92 desferriferrichyrin 92 enterobactin 93
ion substitution, in ferrichrome 92 in siderophores 88 circular dichroism spectra,
of cy tochrome c peroxidase 350 citrate,
as iron chelator 107 CO complexes (see carbon
monoxide complexes) cobalt-substitution,
in cytochrome o 134 in cytochrome P-450 406,409
composition of cytochrome c oxidase 460
compound I, of catalase 428,432 chloroperoxidase 334 cytochrome o peroxidase 391 ferryl species in 29 hemoproteins 391 horseradish peroxidase 29,
334,367,391 formation 340 peroxidases 26
compound II, of horseradish peroxidase 29,368 peroxidases 291
conalbumin (see ovotransferrin) conformational changes
of hemerythrin 157 constraint mechanisms for
hemoglobin 39 contact shift in proton
NMR 359 Cooleys1 anemia 86,118 cooperativity,
in hemoglobin 35 coordination chemistry, of
siderophores 85 transition metal ions 25
coordination environment of iron, influence on
catalatic mechanism 429
sequence data and NMR spectra 135
redox potentials of 128 X-ray structures of 128 cytochrome a 32 in cytochrome a oxidase 459,475 cytochrome ay in cytochrome o oxidase 459,475 cytochrome b 9 32,283 heme in 128
in methanogenic bacteria 210 in Desulfovibrio 210
cytochrome £5, 128 deprotonated imidazole
in 357 Raman spectrum of 377
cytochrome &562 > 128 sixth ligand in 132
cytochrome O 9 26,283 cysteinyl residues in 128 in Desulfovibrio 210 electron transfer in 132 ferri- 34 from mammals 134 from Pseudomonas
aeruginosa 131 Raman spectrum of 377 structure 128
cytochrome c2 in Rhodospirillum rubrum 133
cytochrome c 3
from Desulfovibrio species 136,138,211
heme ligands in 132 ligands of iron in 128 redox titration of 136 titration w ith ferredoxin 140
cytochrome c 551 , from Pseudomonas
aeruginosa 131,133 from Pseudomonas
perfeotomarinus 129 redox potentials of 139 reduction of cytochrome
0 peroxidase by 350
copper, atoms in cytochrome a
oxidase 460 chemistry of 12 location in cytochrome o
oxidase 465 natural abundance of 25 I/II redox couple 12
sites, X-ray absorption spectra of 475 copper A and B,
in cytochrome o oxidase 475,483
EXAFS data on 483 coprogen and coprogen B 1.09 core expansion,
in porphyrins 380 core size indicators
in Raman spectra 380 C pastorianum
hydrogenase 214 nitrogenase 224
cosmic abundance, of the elements 4
cross reactions, Marcus theory for 21
crystal field parameters of hemes 32 9
crystal field theory 35 crystal forms,
of cytochrome P-450cam 408 crystal structures, (see also X-ray structures) of catalase 428 of octameric metheme- rythrin 161 cultured heart cells, rat 117 Curie law in rubredoxins 181 C. vinosum nitrogenase 223 CYCAMS 94 cysteinate ligatio n
in ferre doxins 28 in cytochrome P-450 28
cysteinyl residues bound to cytochrome o 128 in cytochrome P-450 408
cytochromes, 30,32 amino acid substitutions
in 134
cytochrome c oxidase, 11 analytical gel electro- phoresis of 469 assembly 459 biosynthesis of 459 catalytic core of 468 composition 460 copper A and B in 483 copper atoms in 460 copper locations in 465 cytochromes a and
in 459 definition of 460 electron transfer by 459 electrophoresis of 466 elution of subunits 469 EPR detectable Cu in
spectra of subunit 1 471 EXAFS of copper sites in 475 and four-electron reduction
of O2 to water 283 heme a in 460,465 heme a3 in 34 and mitochondrial inner
membrane 460 molecular weight 460 multiplicity of subunits 463 photoreduction of 477,481 preparation of native
subunits 467 prosthetic groups in 461 proton pumping by 459 reduction of oxygen by
330,459 sulfur ligands of copper
A in 473 spectra of subunits I
and II 469 subunits of, 459,463
visible spectra of 467,468 nomenclature 465
XAS of copper sites in 476 X-ray absorption edge
spectra of copper sites in 475
cytochrome c peroxidase (see also Pseudomonas cytochrome Q peroxidase and yeast cytochrome a peroxidase) compound I of 340
cytochrome oxidase (see cytochrome o oxidase) cytochrome P-420, Raman spectrum of 338 cytochrome P-450, 26,28,34 from aorta,
comparison to prosta- glandin synthase 423 axial ligands in 407 carbanions and carbenes
from 413 carbonmonoxide complex
of 289,406 cobalt substituted 406,409 cysteinate ligation in 28,408 ENDOR spectrum of 409 enzymatic activity of 299 expoxidation by 287 EPR spectrum of
intermediate species 410 reactive intermediates 416
ferric peroxide complex in 288
hydroxylation by 2 92 isotopic labelling of Fe,
S, N in 406 ligand field parameters
for 419 mammalian, membrane bound 288 mechanism of hydroxylation
by 300 mercaptide axial ligand
in 407 models, 283
mechanism of oxidation by 295
spectra and structure for 299 theoretical calculation on 295
optical spectra of deriva- tives 289
oxene donors, as models for 422
as an oxene transferase 413 oxenoid complex of 421 oxy-form and oxymyo-
globin 289 oxidation of C-H bonds by 287
of Dieldrin by 291
D, sulfurioans Norway 4 and ATCC 7757,
hydrogenase from 212 D . vulgaris
hydrogenase from 193,203,212 dead end adduct 21 deazoflavin F 4 2 O in
methanogenic bacteria 2 10 deferoxamine (see Desferal) definition of
cytochrome 0 oxidase 460 ENDOR 395 formal charge 27 oxidation state 26 redox potentials 30
deoxyhemerythrin, oxygenation of 147
deoxyhemoglobin, 37 R and T states,
Raman spectra of 379,381 deoxymyoglobin
from sperm whale 362 deferoxamine (see Desferal) deprotonated imidazole,
in hemoproteins 358 Desferal 121,122 desferrichrome 94 desferrioxamine 57,94 desulforedoxin
from D. gigas 183 in Desulfovibrio 210
Desulfotomaculum genera as sulfate-reducing bacteria 210 Desulfovibrio gigas,
cytochrome c 3 in 136,138 Desulfovibrio species,
cytochrome C3 in 132 electron carriers in 210 as sulfate-reducing
bacteria 210 hydrogenases 211
deuteroheme, dimerization in 434
substitution in peroxidase 287 Dieldrin,
oxidation by cytochrome P-450 291
cytochrome P-450 (cont.) oxidized states, Fe(IV) in 411 peroxide shunt in 407 primary structure of 407 in prostaglandin bio- synthesis 413 from Pseudomonas putida 32 Raman spectrum of 408 reaction cycle of 406 mechanism 414 with peroxides 414 with prostaglandin endoperoxidase 422 reduced, Raman spectrum of 377 reduction, of polyhalo- genated hydrocarbons by 413 role of thiolate anion
in 290 similarities to chloro-
peroxidase 344 spectra of states 407 structure of 404 thiolate ligand in 28,413 transient intermediates
of 299 two-electron activation
of O2 by 405 X-ray study of 407 cytochrome P-450 cam (see also cytochrome P-450) 288 dissociation of 405 cytoplasmic membrane, proton motive force across 227 cytosol, ferritin in 120,123
d5 ferric ion, in siderophores 88
d orbitals, energy splitting of 35 symmetry properties of 7
D 4h symmetry, in porphyrins 377
D. gigas, 3Fe-3S centers in 185 ferredoxin II 189
2,3-dihydroxybenzoyl deriva- tives ,
as iron chelators 122 2,3-dihydroxybenzoylserine, from hydrolytic degrada- tion of enterobactin 93 dimerization of ferric
hemes 434 dioxygen reduction 10 displacement reaction of Fe-S centers with o-xylydithiol 189 disproportionation reactions
of hemerythrin 155 dissociative mechanism 14 distinguishability,
of transferrin sites 76 dynamic stability
of horseradish peroxi- dase 367
e g symmetry 8 E O , E 0 ’ scales 30 EDTA, as competitor with enterobactin 93 effective nuclear charge 5 electrochemical oxidations
of metalloporphyrins 284 electron carriers
in Desulfovibrio 210 in methanogenic bacteria
210 electron density map,
for catalase 452 electron exchange
mechanisms in cytochromes 135
electron microscopy of apoferritin 53
electron nuclear double resonance (s ee ENDOR)
electron spin resonance (see EPR)
electron transfer, in cytochromes 136 in cytochrome o 132 in cytochrome c oxidase 459 in hemerythrin 145
to nitrogenase 224 reactions, of iron 20 reactions Marcus theory
for 21 vectorial, across membrane 214,219 electronic quadruple inter- action in Mossbauer spectra 244 electronic spectra for model cytochrome P-450 299 electronic spectroscopy for rate measurements on hemerythrin 146 electronic structure, of the heme of cyto- chromes 131 for model cytochrome P-450 299 electrons, low potential, and nitogenase 226 electrophoresis
of cytochrome c oxidase 466 endocytosis 58 ENDOR,
definition 395 description of techniques 395 of nitrogenase 253 of porphyrin ir-cation
radical 286 of cytochorme P-450 409 of horseradish peroxidase
compound I 345,396 of peroxidase compounds
I 391 energy splitting,
of d orbital energies 35 enteric bacteria,
enterobactin as growth factor for 93
enterobactin, 94,117,122 affinity for ferric ion 103 chronic 93 as competitor with EDTA 93 as growth factor 93 hydrolytic degradation of 93 as iron(III) selector 7
on molybdenum of nitro- genase 253
synchrotron radiation for 476 excess iron,
by blood transfusion 46 exchangeable proton
in imidazole 362 5- ex o -hyd r oxy c amp ho r from cytochrome P-450 reaction 405 extended Hiickel calculation
on hemes 327 extended X-ray absorption
fine structure (see EXAFS) extrusion,
of Fe-S centers 189
fatty acids, from cellulose degrada- tion 208 Fe(-It)
oxidation state 26 Fe(I) oxidation state,
in porphyrins 28 Fe(II), 9 autoxidation of 64 complexes 15,22 hydrolysis 66 one-electron energy levels of 8 Fe(III), 9
biliverdin complex in catalase 440
chelators 57 hydrolysis 66 low and high spin 18 one-electron energy
levels of 8 protoporphyrin IX, in
catalase 440 substitution reactions of 17 Fe(IV), in oxidized peroxidases 339 in cytochrome P-450 oxidized states 411 Fe(VI),
in ferrate ion 26
enthalpy of ionization, of iron 6
EPR detectable copper in cytochrome c oxidase 462
EPR spectra, of chloroperoxidase
compound I 345 of cytochrome o oxidase
subunit I 468 of cytochrome P-450
407,410,416 of hemerythrin 146 of hemes 327 of hemin nitr ites 324 of hydrogenases 193 Kramers1 doublet and 247 of nitrogenase 232,241 of perchlorato iron(III)
complexes 263 of peroxidase compounds
I and II 394 of TT-cation radical 325 of Pseudomonas cytochrome
o peroxidase 350 of semi-met anion adducts
of hemerythrin 149 of transferrin using
Cu(II) 70 epoxidation,
of aliphatic hydrocarbons by cytochrome P-450 2 99
by cytochrome P-450 287 erythrocyte catalase 440 erythrocytes,
iron metabolism in 118 eukaryotic
cytochrome O 9 NMR spectra of 131
cytochrome P-450 405 EXAFS,
of copper sites in cytochrome c oxidase 475
of copper A and B 483 of a cytochrome o oxidase 462 fluorescence excitation of 476 Fourier transforms of
data 481 K-absorption edges in 482 of iron core of ferretin 51
Fe-S centers, extrusion and displace-
ment 189 reactions of 180 role in redox processes 180
2Fe-2S (or Fe 2 -S 2 ) centers, 40,179 models for 185 spectral studies of 184
3Fe-3S centers, 179 in aconitase 187 In ferredoxin II 185 in Me t h an os a rc i n a b a rk e r i
ferredoxin 187 in T h e r mus t he r m op h i l i c s ferredoxin 187 4Fe-4S (or Fez r S^
centers 39, 179 4Fe-4S clusters, 34
in hydrogenase 193 Fenton1 S reagent 66 ferrate ion,
oxidation state of 26 ferredoxins, 26
from A . V i ne la nd i i 3 189 from B . p o l y m ix a 188 bacterial 33 cysteinate ligation in 28 in D e s u l f o v i b r i o 210 3Fe-3« centers, 187
in methanogenic bacteria 210 four-iron 30,40 from M. I a e t y l i t i o u s 201 multiple, in De su l f ov i b r i o 217 role in electron transfer
to nitrogenase 224 thiolate binding in 28 as titrant of cytochrome e 3 140
two-iron 30,40 ferredoxin II from D . g i g as 189 3Fe-3S centers in 185 m.c.d. of 186 ferric (see also Fe(III)) fusarinine 90 hemes, 37
coordination environment in 430
dimerization of 434 in peroxidases 338 hydroxide 85 ion, reaction with catecholates and hydroxamates 86 ion, reaction with thio-
hydroxamates 86 low spin complexes, of cytochromes b 5 and c 377 octaethylporphyrin,
Raman spectrum of 37 9 -oxene complex,
in cytochrome P-450 290 oxyhydroxide,
in ferritin 46 -peroxide complex,
in cytochrome P-450 288 tetraphenylporphinato
complexes 262 geometries of 268
tris benzhydroxamato complexes 90
ferrichrome, 85,90 chromic ion substitution
in 92 iron uptake kinetics of 113
ferrichrome A 90,98 ferrichrome A and C 108 ferrichrysin 90,108 ferricrocin 108 ferricytochrome c ,
NMR spectrum of 129,133 ferrihaems (see ferric hemes,
hemes) ferrimycobactin 90 ferrioxamine B, 86
iron removal from 98 ferrioxamine E 90 ferr!protoporphyrin IX,
in peroxidases 338 ferrirhodin 1099 ferrirubin 108 ferritin,
amino acid sequence of 48 in cytosol 120,123 distribution, role in iron metabolism 46
ferritin, (cont.) ferric oxyhydroxide in 46 function of 45 in hepatocytes 47 from horse spleen 46 iron core,
Mossbauer spectrum of 51 role of phosphate in 53 structure of 51
iron, deposition in 54 mobilization from 56 oxidation in 55
magnetic susceptibility of 51
in mucosal cells 46 non-mammalian 46 production 117 structure 45,48 ferrocytochrome O 9
NMR spectrum of 129,133 ferroxidase activity, of iron-binding proteins 64 ferrous (see also Fe(II)) ion and chain reactions 429 low spin complexes of
myoglobin and hemoglobin 377
ferroxidase, 65 activity of iron-binding proteins 64 ferryl species,
in peroxidase compound I 29 five-coordinate
Fe(III) species 262 high spin ferrous porphyrins 361
flavodoxins, in Desulfovibrio 210
role in electron transfer to nitrogenase 224 flavodoxin hydroquinone,
from A. vinelandii 231 as electron donor to
nitrogenase 225 formation 227 oxidation by nitro-
genase 231
flavoprotein, FAD containing, in cyto- chrome P-450 system 405 Fletcher and Huehns
hypothesis 77 fluorescence excitation
of EXAFS spectra 476 force constants, for Urey-Bradley force field 376 formal charge,
definition 27 formation constants,
of iron siderophores 88 four-electron reduction by
cytochrome o oxidase 283 Fourier transforms,
of EXAFS data 481 free radical
of compound I 391 functions of ferritin 45,54 fungi,
iron chelating agents in 107 and iron supply 107
fungicidal activity of myeloperoxidase 347
fusarinin (see fusigen) Fusarium strain,
siderophores from 109 fusigen 109,122
geometrical isomers 89 gingival fluid
of oral cavity 347 ground states
of porphyrins 285
Haber-Weiss reaction 65 haem (see heme) haemoglobin (see hemoglobin) haemosiderin (see hemosiderin) halogenation
by chloroperoxidase 343 heart cells, cultured rat, iron uptake by 117 heavy atom derivatives
of catalase 448
heme complexes axial ligands in 261 with imidazolate 385 of cytochrome c 128 environment, in catalase, 449 essential residues in 453 of cytochrome c peroxidase 393 of hydroporphyrins 313 iron,
axial ligation of 377 ligands,
in cytochrome 132 -linked ionization
in horseradish peroxi- dase 382
distal, in plant peroxidases 375
structural implications of 383 modification,
of cytochrome P-450 406 pocket, in catalase 454 redox potentials, in
cytochromes 132 synthesis,
in reticulocytes 58 of yeast cytochrome c
peroxidase 392 heme a
in cytochrome c oxidase 60 location 465
heme a 3 of cytochrome c oxidase 34
heme c in Pseudmonas cytochrome
c peroxidase 350 hemerythrin,
autoxidation, inf luence of anions on 152
binuclear iron complex in 161 crystal structure of 161 disproportionation reactions
of 155 electron transfer in 145 EPR spectrum of 146 magnetic susceptibility of 162
net redox reactions of 150 oxy- 39 oxygen transport by 161 Raman spectrum of 376 rate measurements on 146 rates of redox reactions 151 spectroscopic studies on 162 substitution reactions
in 145 semi-met adducts of 149 from Thermiste zosterioola
145 hemochromes,
hexacoordinated 322 hemoglobin, 26
carbonmonoxy - 27 constraint mechanisms for 39 cooperativity 10 deoxy-, 37 T and R states, Raman spectrum of 379 ferrous low spin complexes
of 377 heme substituted,
O2 binding by 321 met-, fluoride complex of 37 oxy- 27 Perutz-Hoard trigger
mechanism for 38 synthesis, by reticuloendo- thelial cells 47 tension theory of cooperativity in 35 hemoproteins, action of 357 compounds I in 391 deprotonated imidazole in 358 Raman spectra of 376 hemosiderin 47 hepatic ferritin
in parenchymal cells 47 high potential iron protein (see HiPIP) high spin complexes, Fe(II) 15 Fe(III), 18
protoporphyrin IX in catalase 440 ferrous model compounds 361 octahedral, of Fe(II) 15
high spin complexes, (cont.) rubredoxins 32
HiPIP, 33 from C h r o ma t i u m 187 oxidized 186 role in hydrogenase mechanism 193,205 super-reduced 193,205 homozygous 3-thalassemia
(see Cooleyt S anemia) hormone control, in plants 342 horseradish peroxidase, calcium ions in 339 compound I 2 9,367,391 compared to chloro-
peroxidase 334 compared to cytochrome
o peroxidase 340 ENDOR of 345,396 EPR spectrum of 394 mechanism of formation 340 Mossbauer spectrum of 394 spectra of 340 stoichiometric EPR signal of 397 compound II 29,368 EPR spectra of 394 Raman spectrum of 377 Mossbauer spectrum of 394 dynamic stability of 367 ferrous, Raman spectrum of 384 heme-linked io nization in 382 isoenzymes A and C,
Raman spectra of 382 hydrogen bonding of proximal
imidazole 357 indolepropionic acid as
substrate for 366 labile protons in 367 low-spin cyanide complex
of 368 primary structure of 339 proton NMR spectra of 357 proximal histidine ligand in 382 reduced, proton NMR of 366 resting state of 366 Soret spectrum of 340
horseradish peroxidase (cont.) state of protonation, of proximal histidine in 357
horse spleen ferritin 46 Hiickel calculations, on ferric hemes 263 in hemes 327 hydrogenases
from D. v u l g a r i s 193,203 in D e s u l f o v i b r i o 210 EPR spectra of 199 from M. e l s d en i i 193,203 in methane-forming
bacteria 207 soluble, from Me t ha no -
s a r o i na ba rk e r i 218 in sulfate-reducing bacteria 207 hydrogen bonding, in catalase 442 of proximal imidazole in horseradish peroxidase 357 hydrogen peroxide, reaction, with catalase 391,427 with peroxidases 339 role in TT-cation radical formation 283 hydrogen production, from
hydrogenases 193 hydrodynamic properties
of transferrin 69 hydrolysis, of Fe(II) and Fe(III) 66 hydroporphyrins, hemes from 313 ligand binding by 317 hydroxamate iron exchange rates 103 reaction with ferric ion 86 siderophores 87 hydroxyl radical, 65 role in destruction of invading organisms and xenobiotics 283 hydroxyIation,
mechanism of, by cyto- chrome P-450 299
hyperfine shifts, in proton NMR spectra 359
hypothiocyanite, production in oral cavity 347
imidazolate, as an iron ligand 370 -heme complexes 385
imidazole binding by hydroporphyrins 317 deprotonated, in hemo-
proteins 358 exchangeable proton of 362
immunoprecipitation of radioiron 120
INDO program, for cytochrome P-450 models 299 indole-3-acetate, in plants 343 indolepropionic acid as
peroxidase substrate 366 inhibition
of iron deposition, by transition metals ions 56
of methanogenesis by sulfides 209 inner membrane
and cytochrome o oxidase 460 inner sphere, redox
reactions 19 interchange, associative and
dissociative mechanism 14 intermolecular electron exchange, in cytochromes 136,139 intracellular iron metabol- ism 117 intramolecular electron
transfer, in multiheme cyto- chromes 136 iodination reactions,
of chloroperoxidase 343 iodosyl benzene,
reaction with porphyrins 290 ionizable groups, in active sites of peroxidases 341,348 ionophores,
role in changing membrane potential 227
invading organisms, and polymorphonuclear leukocytes 283 ionization potentials of first row transition elements 5 iron (see also Fe, ferric, ferrous) 3 (I) porphyrins 28 (II)/(III) potentials 30
binding to entero- bactin 7
spin states 262 six-coordinate
species 262 low spin porphyrin
complexes 370 porphyrin models, for
catalase 433 III/IV potential 30,34 (IV) , oxo-complex in
compound I 29 absorption, in humans 117 aqueous chemistry of 63 binding proteins 64
by transferrin 73 chelating agents, of
fungi 107 chelation, 122 by citrate 107 chelators, effect,
on intracellular iron distribution 117 on iron uptake in heart cells 117 chlorins, synthesis of 313 competition for, by siderophores 111 coordination, in catalase 427 core structure, of
ferritin 51 deficiency 46 deposition, i n ferritin 54 distribution, effect
of chelators on 117,121 enthalpy of ionization 6
redox potentials of 25 properties of 63
reduction in ferritin 56 release from transferrin 73 removal from ferrioxamine
B 98 by EDTA 98
role in pathogenicity of bacterial infections 86 sequestering agents for 94 spin states of 25 sublimation energy of 6 -sulfur bond lengths, in cytochromes 133
centers (see Fe-S centers) clusters, in reductases 330 proteins 30,179
Raman spectra of 376 in P-450 system 405 supply, in fungi 107 toxicity, in humans 86
therapeutic agents for 93 transport, in microbial cells 88 in N e u ros po ra o r as s a 113 in P e n i o i l l i i m pa rv i u m 113 -tyrosyl, class of proteins 70 uptake, effect of chelators on 121
in cultured rat heart cells 117
by microorganisms 107 specificity in fungi 107 isobacteriochlorins,
synthesis of 313 isodesmic reactions 275 isomer shift, in Mossbauer
spectra 245 isomorphous replacement,
in catalase 448 isotopic labell ing,
of cytochrome P-450 406 of octaethylporphyrin Ni complex 376
iron (cont.) excess, from blood trans-
fusion 46 exchange, between ferritin
and transferrin 58 in mammals 46 between siderophores 85 kinetics, between
siderophores 96 rates, for catecho- lates and hydroxa- mates 103
of heme in hemoproteins 261 -histidine stretching
frequency 375 -imidazole bonding 361 -Iigand stretching
frequency 381 magnetic anisotropy of 359 metabolism
in Chang cells 118 in erythrocytes 118 intracellular 117 model systems for 118 role of ferritin in 46
mobilization, from ferritin 56 natural abundance of 25 non-biological, oxidation
states in 26 in non-ferritin cytosol
fraction 120,123 overload, 118
chelating agents for 85 chelation therapy for 103 chronic 86 in humans 117,121 syndrome, therapeutic agents for 93
oxidation, in ferritin 55 oxidation states of 25
from (-11) to (VI) 26 and the periodic table 3
pool, intermediate 118 -porphyrin model systems
for catalase 427 Poubaix diagram for 7 radioactive, immunoprecipita-
tion of 120 rates of electron transfer in
reactions of 20
kinetic model, for lacto- and myeloperoxi- dase oxidation of thio- cyanate 347 kinetics, of
catalase action 431 horseradish peroxidase compound I formation 341 iron deposition, in ferri- tin 56 iron exchange between siderophores 96
iron siderophore complexes 88 K-absorption edge,
in EXAFS data 482 Kekule structure, for porphine 273 KramerT s theorem 246 Kupfer cells, in liver 47
labile protons, in horseradish peroxidase 367
lactate, from cellulose degradation 208
lactate dehydrogenase, analogies with apoferritin 54
lactoferrin 68,75 lactotranferrin 68 l^ctoperoxidase,
ionizable groups in active site of 348
in peroxidation of thio- cyanate 347 laser photolysis
of oxyhemerythrin 148 LFSE (see ligand field
stabilization energy) LICAMS, 94,101,122
55Fe-Iabelled 99 ligand binding,
by iron hydroporphyrins 317 dynamics 25
ligand field 31 parameters, of cytochrome
P-450 complexes 419 stabilization energy 31 strength 36
ligand substitution mechanisms, associate, dissociative and interchange 14 ligands,
of iron, in cytochrome o ^ 128 in low spin cytochrome o 128 soft/hard, characteristics of 31
low spin cyanide complex, of horseradish peroxidase 368 cytochromes, NMR studies on 127 cytochromes O 9 l igands of
iron in 128 Fe(II) 15 Fe(III) 18
ferric iron, in porphyrins 361 model porphyrin complexes of Fe(III) 370 low potential electrons, and nitrogenase 226
M. e l s d en i i f lavodoxin hydroquinone oxidation by nitro- genase 231 hydrogenase 193,203,214 magnetic hyperfine inter- action ,
in Mossbauer spectra 243 properties, of porphinato iron(III) complexes 261 magnetic susceptibility,
of ferritin iron core 51 of hemerythrin 162 of cytochrome P-450 407
mammalian cytochromes o 134 peroxidases 337
polymorphonuclear leukocytes 283 Marcus theory, for electron
transfer reactions 21 marker lines,
for axial l igation 379 for core expansion 379 extreme values for 377 for Raman spectra 376
Methanobaotevium bryantii 217 thermoautobrophicum 218 methanogenic bacteria,
electron carriers in 210 methenogenesis, inhibition by sulfide 209 Methanosaroina 215 barkeri ferredoxin 187 hydrogenase 214 soluble hydrogenase from 218 methemerythrin,
-azide, photochemical reduction of 155 crystal structure of 161 photochemical reduction of 153 reduction of anion adducts
154 methemoglobin,
fluoride complex 37 methydroxyhemerythrin,
structure of complex 166 5-methyl-imidazole, as
iron ligand 370 methyl viologen semiquinone,
oxidation by nitrogen ase 231 metmyoglobin,
cyanide complex 368 microbial
cells, in transport in 88 growth factors, sidero-
phores as 86 iron transport compounds (see siderophores) Miorooooous lactylitious
ferredoxin 201 mitochondrial inner membrane
and cytochrome e oxidase 460 proton transfer acro ss 46 0
mitochondrial structure, and cytochrome c oxidase 459
mixing of spin states 38 model compounds of
2Fe-2S centers 184 cytochrome P-450 295 siderophores 26 catalase 427
marine invertebrate phyla, hemerythrin in 161
MECAM 122 MECAMS, 94,101 potentiometric titration of 95 mechanism of
active oxidizing agent of cytochrome P-450 291
cytochrome P-450 414 electron exchange in
cytochromes 135 horseradish peroxidase
compound I formation 341 interspecies hydrogen
transfer 209 iron binding to trans- ferrin 73 iron release from trans- ferrin 73 oxidation by model cyto- chrome P-450 295 cytochrome P-450 hydroxyla- tion 292 membrane organization, of catalytic core of cyto- chrome e oxidase 468 membrane potential,
cytoplasmic 227 mercaptide-CO complex of protoheme 288 mercaptide ligand, in cyto- chrome P-450 407 mesoporphyrin, in cytochrome c
128 metabolism, of ethanol and CO2 209 of iron 46,117 metalloporphyrins,
electrochemical oxidation of 284
metazidehemerythrin, structure of complex 166
methane formation, from bacteria 207 by cellulose degradation 207
Methanobacillus Omelianski3
metabolism of ethanol and CO2 by 209
model systems for cellular iron meta- bolism 118 models,
for peroxidase and cyto- chrome P-450 283
synthetic, for porphyrins 315 MoFe protein (see nitrogenase) molecular weight, of cytochrome
c oxidase 460 molybdenum-iron protein (see
nitrogenase) monomeric species, of heme-
rythrin 151 monoxygenase, cytochrome P-450
as a 405 Mossbauer spectra,
of chloroperoxidase compound I 345
correlation with EPR spectra 246
of cytochrome P-450 states 407 of ferritin iron core 51 Kramers doublet and 247 of nitrogenase 241 paramagnetic components of
nitrogenase 248 of perchlorato iron(III)
complexes 263 of peroxidase compound I 29 of peroxidase compounds I
and II 394 quadrupole doublets from
nitrogenase 248 of rubredoxin 183 theory for 242
multidentate ligands, substitution by 18
multielectron reductions 330 multiheme cytochromes,
redox equilibria in 136 multiplicity of subunits,
in cytochrome c oxidase 463 myeloperoxidase,
antimicrobial activity of 347 fungicidal activity of 347 ionizable groups in active
site of 348 in leucocytes 283
in neutrophils 347 in peroxidation of thio- cyanate 347 myocytes, cultured rat 117
radioiron uptake in 119 myoglobin, 10
ferrous low spin complexes of 377
heme substituted, O2 binding by 321
reconstituted 322
N,N’,N"-tris(2,3-dihydroxy- 5-sulfobenzoyl)- 1,5,9-cyclotriazatridecane (see CYCAMS) 1,5,10-triazadecane (see
LICAMS) 1,3,5-triaminomethylbenzene (see MECAMS) natural abundance, of Cu and Fe 25 Nernst equations, for multi- heme cytochromes 138 neutrophils,
myeloperoxidase in 347 Neurospora Crassa3
iron transport studies with 113
siderophores from 108 nitric oxide, binding by
hydroporphyrins 317 nitrite ion binding,
by hydroporphyrins 317 nitrite reductases 314,329 nitrogen fixation 224 nitrogenase, 241
from A . vinlandii 250 from C pasteurianum 248 ENDOR study of 253 electron transfer to 224 -enzyme complex components of 242 iron protein (component I)
242 Mo-Fe protein (component II)
242 EPR spectra of 232,241,248
nitrogenase (cont.) EXAFS study of 253
inhibition 229 low-potential reducing equivalent in 223
Mossbauer spectrum of 241 quadrupole doublets of 248 paramagnetic spectrum 248
P-clusters in 253 NMR spectra,
of cobalt-substituted cyto- chrome c 134
correlated with sequence data in cytochromes 135
of cytochrome P-450 states 407 of cytochromes 129 of eukaryotic cytochromes a
131 of ferricytochrome o 129 of ferrocytochrome c 133 of low spin cytochromes 127 proton, of horseradish peroxidase 357 NOE (see nuclear Overhauser effect) non-biological iron, oxidation
states in 26 non-heme iron
dioxygenases, Raman spectra of 376
proteins in D e s u l f ov i bv i o 210 non-mammalian ferritin 46 nuclear charge, effective,
of transition metals 5 nuclear Overhauser effect, 131
in cytochromes 132
O2 binding, by substituted myo- globin and hemoglobin 321
O17 labelling, of horseradish peroxidase compound I 399
octaethylporphinato Ni complex, isotope labelling of 376
octahedral, complexes, of iron 15,22 symmetry 8
octameric species, of hemerythrin 151
one-electron energy levels, of Fe(II) and Fe(III) 8
optical isomers, 89 of tris(hydroxamato) metal complexes 89 optical spectra, of cytochrome P-450 derivatives 289 oral cavity, bacterial growth regula- tion in 347 organic substrate halogena-
tion, by chloroperoxidase 343 outer sphere reactions 19 ovotransferrin 68,75 oxene
donors, as models for cytochrome P-450 422
transfer, in prostacyclin biosynthesis 413 transferase, cytochrome P-450 as 413 oxenoid complex, of cyto- chrome P-450 421 oxidation,
of C-H bonds by cytochrome P-450 287
of Dieldrin, by cytochrome P-450 291 by model cytochrome P-450 295 of tetradeuteronorbornane by P-450 model 291 oxidation-reduction (see redox) oxidation states, definition 26 of ferrate ion 26 and formal charge 27 of iron, 25
from (-II) to (VI) 26 markers, in Raman spectroscopy 376
of non-biological iron 26 oxidized HiPIP 186 oxo-complex, of Fe(IV) in compound I 29 oxy-ferryl nature of compound I 391
oxygen, redox chemistry of 283 singlet 283 transport,
by hemerythrin 161 and respiration 161
oxygenation, of deoxyheme- rythrin 147
oxyhemocyanin, peroxide ion in 27
oxyhemerythrin, 39 laser photolysis of 149
oxyhemoglobin, 27 superoxide ion in 27
oxymyoglobin, and oxy-P-450 279
paramagnetism, in hemoprotein 359
P-cluster, in nitrogenase 253 P e n i c l l i u m p a rv u r r i j iron transport in 113 strain, siderophores from 108 V t t a l e i catalase from 441 peptide mapping, of turnip peroxidases 341 perchlorato iron(III) complexes,
EPR spectra of 263 periodic table, and iron 3 peroxidase, (see also peroxidases) peroxidase compound I Mossbauer spectrum 29 oxyferryl and free radical nature of 391 compounds I and II, descrip- tion of 394 compound II 391 model for 283 proximal imidazole in 286 chloroperoxidase, cytochrome o peroxidase, peroxidases (see also horse- radish peroxidase, lacto- peroxidase, myeloperoxidase, plant peroxidases, P s e ud o mo nas cytochrome o peroxidase, turnip peroxidase, yeast cyto- chrome o peroxidase)
peroxidases, 11,26,337 compound I of 26 Fe(IV) in 339 in mammals 337
peroxidatic activity, of catalase 428,440 of peroxidase 337
peroxidation, of thiocyanate by peroxidases 347 peroxide ion, in oxyheme- rythrin 27 peroxides,
peroxygenase shunt in P-450, induced by 407
reactions with cytochrome P-450 414 Perutz-Hoard trigger
mechanism, for hemog lobin 39 P h aso o l ops i s g o u l d i i ,
hemerythrin from 163 phosphate, role in ferritin
iron core 53 photochemical reduction,
of methemerythrin 153 of methemerythrin-azide
adduct 155 of cytochrome o oxidase 477
physiology, of transferrins 63 Ti-bonding 36 TT-bonds, in axial ligation
of heme iron 377 TT-cation radical,
EPR spectrum of 325 in oxidized peroxidases 283 in peroxidase compound I 29 in porphyrins 283,396
TT-spin density, in porphyrins 359
picket fence porphyrin 39 ping-pong kinetics,
modified, of peroxidases 338 plant hormone control 342 plant peroxidases, 339,341
Raman spectra of 375 plasma copper protein (see
ceruloplasmin) pM values, of ferric sidero-
phores 94,102
polyhalogenated hydrocarbons,
reduction by P-450 413
polymeric iron hydroxides 107
polymers, of iron 51
porphine,
compared to [18] annulene 279
Kekule structure for 273
resonance energies for 273
porphinato (III) complexes,
magnetic complexities in 261
structure of 261
porphyrin
complexes, low-spin Fe (III)
370
ligands 9
p-cation radicals 283,396
in peroxidase compound
I 29
p-spin density 359
porphyrin, picket fence 39
reaction with iodosyl
benzene 290
ring, resonance energy of 339
a spin density 361
porphyrins, (see also porphine)
core expansion in 380
containing iron (I) 28
potentiometric titration, of
MECAMS 95
Poubaix diagram, for iron 7,8
precursor complex 18
primary structure,
of cytochrome P-450 cam 407
of horseradish peroxidase 339
prokaryotic cytochrome P-450 405
prostacyclin,
biosynthesis involving
P-450 413
synthesis, in arterial
walls 422
prostacyclin synthase,
comparison to aorta P-450 423
prostaglandin endoperoxide,
reaction with cytochrome
P-450 422
prosthetic groups, of cytochrome
c oxidase 461
of Pseudomonas cytochrome c peroxidase 350
protein, role in catalase
catalysis 434
protoheme-mercaptide-CO
complex 288
proton motive force,
across cytoplasmic
membrane 227
proton NMR, (see also NMR)
contact shift in 359
hyperfine shifts in 359
of reduced horseradish
peroxidase 366
proton pump,
bioenergetics of 475
proton transfer,
across mitochondrial
membrane 460
protoporphyrin IX
in cytochrome b 128
proximal histidyl residue,
in horseradish peroxi-
dase 357,382
Pseudomonas aeruginosa cytochrome o in 131
cytochrome £551 in 131,133,
139
cytochrome 0 peroxidase
from 349
Pseudomonas cytochrome 0 oxidase, hemes in 313
Pseudomonas cytochrome c peroxidase, 349
circular dichroism spectrum
of 350
CO titration of 350
prostheticgroups in 350
reduction by azurin 351
reduction with cytochrome
C 5 5 1 350
Soret spectrum of 350
resonance Raman spectrum
of 350
Pseudomonas perfeotomarinus cytochrome £551 in 130
Pseudomonas putida3
cytochrome P-450 from 405
putidaredoxin, 32
in cytochrome P-450
systems 405
quadrupole doublets, in
Mőssbauer spectra 248
quantum mechanical mixing
in porphyrin ground
states 287
quaternary structure, in
catalase 449
radioiron uptake, by rat
myocytes 119
Raman scattering 375
Raman spectra,
accurate measurement of
small frequency shifts
in 378
core size indicators in 380
of cytochrome P-420 378
of cytochrome P-450 408
of deoxyhemoglobin, T and
R states 379 of ferric octaethylpor-
phyrin 379
of ferrous horseradish
peroxidase 384
of hemerythrin 376
of hemoproteins 376
of horseradish peroxidases
A and C 382
of horseradish peroxidase
compound II 377
influence of axial ligation
on 381
of iron-sulfur proteins 376
marker lines, 376
for axial l igation 379
for core expansion 379
of myoglobin and hemoglobin,
low spin 377
of non-heme iron dioxy-
genases 376
of Pseudomonas cytochrome o peroxidase 350
of plant peroxidases 375
of reduced cytochrome
P-450 377
of transferrin 376
rat myocardial cells,
iron uptake by 119
rate constants,
for CO binding by hemes 319
for electron transfer
reactions of iron 20
rates, of net redox reactions
of hemerythrin 151
reaction cycle,
of cytochrome P-450 406,414
of horseradish peroxidase 337
reactions, of Fe-S centers 180
reconstitution,
of cytochrome P-450, with
modified hemes 406
redox chemistry, of oxygen 283
redox equilibria, in
multiheme cytochromes 136
redox potentials,
of chlorins 325
of Cu(II)/Cu(I) 12
of cytochromes 128
of cytochrome £55^ 139
definition 30
of dithionite/sulfite
complex 229
of Fe(II)/Fe(III) 30
of Fe(III)/Fe(IV) 30
influence of pH on 31
of iron 31
of transition metals 5
redox properties, of iron 63
redox reactions, net,
of hemerythrin 150
redox titration,
of cytochrome £3 136
reduced pyridine nucleotides,
possible role in N2
fixation 224
reductases,
for nitrite 314
reduction,
of methemerythrin-anion
adducts 154
of O2 to water by cytochrome
0 oxidase 459
of protons 207
of sulfate 207
reduction potentials (see
redox potentials)
siderophores, 7 catecholate 87 chromic ion substitution in 88 competition between for
iron 111 complexes, kinetics of 88 coordination chemistry
of 85 d5 ferric ion in 88 formation constants for 88 from different bacterial
strains 108 hydroxamate 87 iron exchange between, 85
kinetics of 86 iron transport by 110 as microbial growth
factors 86 model compounds for 26 pM values for 94,102 specificity of 107 and specificity of iron
uptake by fungi 107 stereoselectivity of
uptake by 113 synthetic analogs for 85 transport system 110
s -bonding 36 s -non bonding 36 s -bonds, in axial ligation
of heme ir on 377 s spin density, in
porphyrins 361 singlet oxygen 283 siroheme, structure of 314 six-coordinate Fe(III)
species 261 sixth ligand, in cytochrome
b 5 6 2 132 soft/hard ligand character-
istics 31 Soret spectra, of
peroxidase compounds 340 of Pseudomorias cytochrome 0 peroxidase 350
specificity, of sidero- phores 107
spectra, of model cytochrome P-450 295
resonance energies, of [18] annulene 273 of benzene 273 of porphine 273 of porphyrin ring 339
resonance Raman spectra (see Raman spectra)
respiration, and oxygen transport in marine invertibrates 161 reticulocyte heme synthesis 58 reticuloendothelial system,
and hemoglobin synthesis 47 Rhodospirillum Tubrum3
cytochrome 02 in 133 Rhodotorula pilimanae,
rhodotorulic acid in 89 Rhodotorula strain
rhodotorulic acid from 109 rhodotorulic acid 57,89,94,109,
122 rubredoxin, 36
and desulforedoxin, compari- son of 183
from C. pasterurianum 181 from D. vulgaris 181 in Desulfovibrio 210 EPR spectrum of 181 high spin 32 Mossbauer spectrum of
ferrous 183 structure of 179 X-ray studies of 181
S 3 / 2 / S 5 / 2 mixing of states 38 saturation kinetics 15 schizokinen 122 secondary structure, of
catalase 444 sequence data, of
cytochromes 135 sequestering agents, for
iron 94 serum transferrin 72 sideramines (see sidero-
phores) siderochromes (see
siderophores)
spectral studies, on 2Fe-2S centers 184
spectroscopic studies, on hemerythrin 162
spin-lattice relaxation times, in cytochromes 135
spin state mixing 38 spin states, of iron 25 splitting, of d orbital
energies 35 stabilization energies,
of ligand fields 31 resonance 273
standard reduction potentials (see redox potentials)
stereochemical probes, chromic siderophores as 89
stereoselectivity, of sidero- phofe uptake 113
stretching frequency, of iron-histidine bond 375 of iron ligand bond 381
structure, of apoferritin 48 beef liver catalase 439 binuclear complex of
hemerythrin 165 bonellin 314 cytochrome o 128 cytochrome P-450 405 ferritin 45,48 ferritin iron core 51 model cytochrome P-450 295 porphinato iron(III)
complexes 261 siroheme 314
yeast cytochrome c peroxidase 392 structural control,
of heme redox potentials 132 structural studies, by NMR
of cy tochromes c 133 sublimation energy, of
iron 6 substitution, mechanism 13
by multidentate ligands 18 reactions of Fe(II) 16 reactions of Fe(III) 17 of hemerythrin 145,147
subunit nomenclature, in cy tochrome c oxidase 4 65
subunits, of beef liver catalase 440 of cytochrome c oxidase
459,463 native, of cytochrome o oxidase, preparation of 467 successor complex 18 sulfate reducing bacteria, from Desulfovibrio genera 209 from Desulfotonaculum genera 209 sulfate reduction, by bacteria 207 and relation to proton reduction 207 sulfide inhibition,
of methanogenesis 209 sulfite reductase, 329
prosthetic group in 314 sulfur ligands, of CuA in cytochrome a oxidase 475 superoxide dismutase 11 superoxide ion, in chain reactions 429 in oxyhemerythrin 27 Swank-Munkres procedure, for analytical gel electrophoresis 469 symmetry, D4h, in porphyrins 377 of octahedral orbitals 8 properties, of d orbitals 7 synchrotron radiation,
for EXAFS st udies 476 synthesis, of porphyrin models 315 synthetic analogs, for siderophores 85
t2g symmetry 8 tetradeuteronorbornane oxidation by cytochrome P-450 291
-ferritin iron exchange 58 Fletcher and Huehns
hypothesis for 77 hydrodynamic properties
of 69 interaction with cells 73 mechanism of
iron binding by 73 iron release from 73
Raman spectrum of 376 structure of 75 two-domain hypothesis
for 75 transient intermediates,
in cytochrome P-450 reactions 299
transition elements, ioniza- tion potentials of 5
transition metal ions, inhibition of iron deposition by 56
transition metals, redox potentials of 5
triacetylfusarinin (see triacetylfusigen)
triacetylfusigen 109 tricatechoylamide sequester-
ing agents, 101 for iron 94
tris (tricatecholato)- chromium(III), as model for enterbactin 92
tris(hydroxamato) metal complexes y isomers of 89
trigger mechanism, for hemoglobin 39
turnip peroxidases, 341 compound I formation in 342 peptide mapping in 341 role in controlling indole-3-acetate 342
two-domain hypothesis, of transferrin structure 35
two-electron activation of O2 by cytochrome P-450 405
tyrosine, as proximal ligand in catalase 439
tetraphenylporphyrins, 29,38,40
tension theory, of cooperativity in hemo- globin 35 T h e mi s t e d y Q c v i t w f i 5
octameric hemerythrin in 163 theoretical calculations,
on cytochrome P-450 models 295 of spectra and structure of P-450 models 299 therapeutic agents,
for acute iron toxicity 93 for iron overload syndrome 93
T h ev m is t e Z os t ev i c o l a i
hemerythrin in 145 T h ev mus t h evm o ph i l us 3
ferredoxin from 187 T h i ob ao i l l us f evv i ox i dans 3
autotoxidation of Fe(II) in 65
thiocyanate peroxidation, by lacto- and myelo- peroxidase 347 thioether linkages,
to iron of cytochrome o 128 thiohydroxamates, reaction
with ferric ion 86 thiolate anion, role in
cytochrome P-450 2 90 thiolate binding,
in cytochrome P-450 28,143 in ferredoxins 28
three-dimensional model, of crystal structure of octameric hemerythrin 161 three-dimensional structure,
(see also structure) of beef liver catalase 439
titration of cytochrome c 3
with ferredoxin 140 TPP (see tetraphenylporphyrins) transferrin, 18,46,57,67,118
amino acid composition and sequence in 69
chemistry and physiology of 63
distinguishability of the sites in 76
EPR spectrum of 70
Urey-Bradley field, force constants for 376
Us t i Za go strain, sidero- phores from 108
vibrational frequencies, of ground electronic states
376 visible spectra,
of cytochrome o oxidase subunits 467,468
of rubredoxin 183
XAS, of copper in cytochrome o oxidase 476
xenobiotics, and mammalian polymorpho- nuclear leukocytes 283 X-ray absorption edge
spectroscopy, of cyto- chrome o oxidase 461
of copper sites in cyto- chrome o oxidase 475 X-ray absorption spectro- scopy (see XAS) X-ray diffraction study,
of cytochrome P-450 cam 407 X-ray structure, of (see also
structure) A . v i n e l a n d i i ferredoxin 189 catalase 428 beef livep catalase 439 cytochrome c peroxidase 392 cytochromes 128 porphinato iron(III)
complexes 264 rubredoxin centers 181
yeast cytochrome c peroxidase, 10
compound I in, 391 ENDOR and EPR of 400 EPR and Mossbauer of 395 and metmyoglobin, compari- son of 393 heme of 392 properties of 392