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Molecular Biology of the Cell Fifth Edition Alberts ● Johnson ● Lewis ● Raff ● Roberts ● Walter

Different groups of organisms produce cellulose

Bacteria Plants Animals

Cellulose pellicle produced by Gluconacetobacter xylinus

Chemical constitution of cellulose as 1-4-linked -D-anhydroglucopyranose and numbering of carbon atoms in the representation of Haworth (1929, 1932). The equatorial position (-position) of C1–O1 is given by O1 above the ring with O5 at the back

Schematics of (a) single cellulose chain repeat unit, showing the directionality of the 1 - 4 linkage and intrachain hydrogen bonding (dotted line), (b) idealized cellulose microfibril showing one of the suggested configurations of the crystalline and amorphous regions, and (c) cellulose nanocrystals after acid hydrolysis dissolvedthe disordered regions

Fleeces of bacterial nanocellulose produced by two differentGluconacetobacter strains (left: DSM 14666; right: ATCC 23769;DSM=Deutsche Sammlung fr Mikroorganismen und Zellkulturen,Braunschweig, Germany; ATCC=American Type Culture Collection,Manassas, VA, USA) and the corresponding electron micrographs(scale bars: 2 mm).

BNC hydrogels formed in situ. a) Film prepared in a PPcontainer under static conditions; dimensions: 2525 cm2, thickness:200 mm.[181] b) Spheres formed by agitated cultivation with a shakingrate of 80–100 rpm; diameter: 2–3 mm, smooth surface.[181] c) Tubescreated by a matrix technology as blood-vessel implants; innerdiameter: 0.6–6 mm.

Tube of bacterial nanocellulose designed by a matrix technologyand presented on a red glass rod, which symbolizes the bloodflow when the tube is used as a blood-vessel substitute; innerdiameter: 6 mm, length: 15 cm

BNC tube used as a long-segment vascular graft (5 cm) forthe right carotid artery of a sheep (courtesy: Priv.-Doz. Dr. J. Wippermann, Department of Cardiothoracic Surgery, University Hospital Cologne, Germany).

Schematic of the tree hierarchical structure

Schematics of rosette and linear TCs (adapted from Brown et al.71), for (a) wood, plants (6 chains/subunit), green algae (Micrasterias), (b) Tunicate (Metandroxarpa uedai) (unknown number of chains/subunit) (adapted from Kimura et al.64), (c) green algae (Valonia) (10–12 chains/subunit), (d) red algae (Erythrocladia) (4 chains/subunit), (e) yellow-green algae (Vaucheria) (1 chains/subunit), and (f) bacterial (Acetobacter) (16 chains/subunit). Each dark circle represents a single subunit

Schematic of the different levels of the formation of a wood microfibril (a) minisheet cross-section believed to form from a single subunit, in which van der Waals forces hold the cellulose chains together. Each grey box represents a cellulose chain looking down the chain-axis. (b) elementary fibril cross-section, the assembly of 6 minisheets into a cellulose crystal I lattice of B3–5 nm dimensions. The consolidation of multiple elementary fibrils forms a microfibril, (c) microfibril cross-section composed of 6 elementary fibrils (modified Frey-Wysling model),392 (d) microfibril lateral section showing the series configuration of crystalline and amorphous regions.

Origin and evolution of cellulose synthase (CesA) genes in the tunicate lineageHorizontal transfer of a prokaryotic CesA-like gene to the common ancestor of the tunicates. Two

scenarios are possible. The horizontally transferred gene underwent gene duplication at the base of the tunicate lineage and was retained in larvaceans (Appendicularians), while being lost in ascidians.

Alternatively, gene duplication occurred specifically in the larvacean lineage, with ascidians retaining the ancestral single-copy state. The gene(s) responsible for cellulose production in thaliaceans have not yet

been isolated.

Functional specialization of cellulose synthase genes ofprokaryotic origin in chordate larvaceans