Cellulophaga lytica : the “Microbial Mascot” of Northwestern College
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Transcript of Cellulophaga lytica : the “Microbial Mascot” of Northwestern College
Joanna Klein, Ph.D.Northwestern Scholarship Symposium
May 10, 2013
Cellulophaga lyticaMarine bacterium of the
CFB groupIsolated from beach mud
near Limon, Costa Rica in 1969
http://www.infoplease.com/atlas/centralamerica.html
http://travel.yahoo.com/p-travelguide-482616-limon_vacations-i
Cellulophaga lyticaGram negative FilamentousYellow pigmentationExhibits gliding motilityDegrades cellulose
Cellulophaga lyticaTarget organism in the Genomic Encyclopedia of
Bacteria and Archaea (GEBA) Research Program of the Department of Energy/Joint Genome Institute
GEBA organisms 100 representative
organisms from each of the branches
Organisms with potential energy applications
C. lytica: Northwestern’s “microbial mascot”Interpret a genome for education
JGI Genome Annotation Workshop, Walnut Creek, CA, January 2011
Why study C. lytica?Model organism to understand the CFB
group betterContribute to biofuel research and
applicationsUnique method of motility: Gliding
Biofuel productionC. lytica produces a variety of
enzymes that may have applications in biotechnology and biofuel production
Ethanol productionEthanol produced as a byproduct of starch
degradation and subsequent fermentationWell developed technologyEnzymes digest starch into simple sugars
which are readily fermented by known microorganisms to produce ethanol
Issues…
Cellulosic ethanol productionGoal is to use the cellulose biomass found in
plant cell walls of leaves and wood to produce ethanolProblems to overcome:
Lignin, also found in cell wall, hinders digestion of cellulose from wood
Enzymes that digest cellulose into simple sugars are poorly understood
Organisms that ferment these simple sugars to produce ethanol are poorly understood
Can C. lytic help achieve this goal?Predicted to encode 3 cellulase enzymes
3 Cellulase genes of C. lytica
Cellulase 1Cellulase 2Cellulase 3
Plant Cell Wall
Cellulase Enzymes in C. lytica
Purpose: To determine if the predicted cellulase enzymes in C. lytica are capable of degrading cellulose.
Method: Evaluate an assay for cellulose degradation in
C. lytica Transfer a cellulase gene from C. lytica to E.
coli, which does not degrade cellulose, and determine if E. coli can now degrade cellulose.
Grow bacteria on agar plates for 48 hoursCover with top agar containing 1%
carboxymethylcellulose (CMC) and incubate 24 hours
Flood with Congo Red Congo red binds to CMCAreas where CMC has been degraded will not
be stained – zone of clearance
Cellulase Degradation Assay - Congo-Red Plate Assay
Congo Red Assay: E. coli TOP10 and C. lytica were grown on a TSA plate containing 2% Salt + 1% carboxymethylcellulose. After flooding with Congo Red and fixing the stain, a zone of clearing was observed around C. lytica but not around E. coli.
MethodTransfer a cellulase gene from C. lytica to E.
coli, which does not degrade cellulose, and determine if E. coli can now degrade cellulose.
PCR amplify a cellulase gene from C. lytica
Insert the cellulase gene into the TOPO-TA plasmid
Transfer the recombinant plasmid into E. coli TOP10
Expresses cellulase enzyme in E. coli
Determine if E. coli can degrade cellulose using the congo red plate assay
PCR Amplification
PCR amplification of cellulase 1 gene from C. lytica (lane 3)
3 of 5 clones had cellulase activity
Fugure WorkClone 2 remaining cellulase genes and test for
activityCellulase 3 gene was PCR amplified and cloned
into TOPO-TA vectorNone of the 10 clones exhibited cellulase activity
Verify correct plasmid constructionCellulase 2 failed in PCR amplification
Troubleshoot PCR procedure
Perform similar experiments with additional polysaccharide degrading enzymes from C. lytica
Gliding motility in C. lyticaGliding allows bacteria to move across
surfaces
Gliding Motility in C. lytica
Gliding MotilityResearch in Flavobacterium indicates over 20
proteins are involved in gliding cell membrane localization6 are lipoproteinsMany make “motor” that propels the cellsprB is thought to be a surface protein and
adhesin propelled along surface by motor
Genome Annotation of gliding motility genes of Cellulophaga lytica
Genetics students annotated 11 of these predicted gliding motility genesgldA Alyssa/Emily
gldF Not annotated
gldG Not annotated
gldH Kait/Alannah
gldD Isaac/Sam
gldI Brittany/Kristen
gldB Kayla/Josh
gldC David/Andy
gldE Drew/Aaron/Joey
gldK Naomi/Taylor
gldL Mac/Bri
gldM Ella/Nyemo
gldN Anna/Alyssa
What is annotation?One way to understand more about the life
processes of C. lytica is through a study of its genome.
GenomeAll of the genetic material, DNA, of an
organismDNA is made up 4 smaller molecules known as
the bases A,C,G &T
Genome projectsWe can easily determine the entire DNA
sequence of an organism – it’s genome.Currently, there are more than 3000
complete or nearly complete genome sequences of microbes available.
The complete genome of Cellulophaga lytica was sequenced by the DOE and published in 20113,765,936 bases
Genome Projects
TATCAAAGAGATGATTGAGAACTGGTACGGAGGGAGTCGAGCCGGGCTCACTTAAGGGCTACGACTTAAC GGGCCGCGTCACTCAATGGCGCGGACACGCCTCTTTGCCCGGGCAGAGGCATGTACAGCGCATGCCCACA ACGGCGGAGGCCGCCGGGTTCCCTGACGTGCCAGTCAGGCCTTCTCCTTTTCCGCAGACCGTGTGTTTCT TTACCGCTCTCCCCCGAGACCTTTTAAGGGTTGTTTGGAGTGTAAGTGGAGGAATATACGTAGTGTTGTC TTAATGGTACCGTTAACTAAGTAAGGAAGCCACTTAATTTAAAATTATGTATGCAGAACATGCGAAGTTA AAAGATGTATAAAAGCTTAAGATGGGGAGAAAAACCTTTTTTCAGAGGGTACTGTGTTACTGTTTTCTTG CTTTTCATTCATTCCAGAAATCATCTGTTCACATCCAAAGGCACAATTCATTTTGAGTTTCTTTCAAAAC AAATCGTTTGTAGTTTTAGGACAGGCTGATGCACTTTGGGCTTGACTTCTGATTACCCTATTGTTAAATT AGTGACCCCTCTTAGTGTTTTCCTGTCCTTTATTTCGGAGGACGCACTTCGAAGATACCAGATTTTATGG GTCATCCTTGGATTTTGAAGCTTATAACTGTGACAAAAAATGTGAAGGGAAGAGATTTGAAACATGTGGA AGGAAAAGTGAGTGCAGACTATAAACTTCCAAAAAGACAAGCCCAAAATACACCTAAACGTTATGTCAGA TTATTTTGTTAAAATCAGTTGTTAGTGACGTCCGTACGTTAATAGAAAAAAGAATGCTTCAGTTTGGAGT GGTAGGTTTCTAGAGGGATTTATTGTGAAAGTATAAACTATTCAGGGCAATGGGACTGAGAGAACAGTGG GTAGAAAGGACCACTGAAGGAAAGGAAGAGAATTGGAAGGTAGATGAAAGAAGGAGCAAGAACCTGGGGTGTTTTTTCCTTTTCACTTGTAATAGTAGTAACAGAAGCAATGGCAGACTGGCTTTTGTTTCTACTGTGT TAGAATGAATTGACAGGACAACTGGGCCTATTATTGTACTGTGCCAGAATACTGTAAAACAAAACTAAAC ATACTAGCTTGGTGGCTTGTAATTAATTACTTAAGTGGAGATTTTTATTTTTTTTTTATTTTTTTTTTAG ACGGAGTCTCACTTTGTCACCCAGGCTGGAGTGCAGTGGCGCGATCTCAGCTGACTGCAACCTCCTCCTC
Cellulase
Process of annotationAutomatic annotation - done automatically using
computer software
35% of computer generated annotations are wrong or are missing information due to limitations of computer algorithms
Manual Annotation – humans analyze the information generated by computers and make corrections as necessary. Labor intensive and time consumingSolution: Train students to participate in the
process
• IMG-ACT is a toolkit of online gene and genome analysis programs.
• Using IMG-ACT, students annotate genomes• provide human expertise necessary for
accurate, up-to-date, reliable annotation• Students contribute to the scientific
community and learn biological concepts through participating in original research
Annotation of Gliding Motility Genes in C. lytica
The computer based annotation of all 11 genes was confirmed through manual annotation by students
Genome annotation of C. lytica at NWC64 NWC students have participated in this
research projectScience Research Institute, Summer 2011Genetics, Fall 2011Microbiology, Spring 2012Genetics, Fall 2012Research Students
29 genes have been fully annotated10 genes have been partially annotated
Future work3,334 genes left to annotate!Study the function of interesting genes in the
lab
AcknowledgementsNWC students who have participated in this
research.Genetics, Microbiology and SRI coursesResearch students: Steven Erickson, Andy
Jaeger, Silas Baalke, Hannah Bardwell, Rachel Blesi, Trevor Diercks
Funding received from a 2012 Faculty Development Grant to purchase research supplies
Questions?