Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells.
The mechanisms by which Geobacter sulfurreducens transfers electrons through relatively thick (>50 microm) biofilms to electrodes acting as a sole electron acceptor were investigated. Biofilms of Geobacter sulfurreducens were grown either in flow-through systems with graphite anodes as the electr...
| Main Authors: | , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2009-05-01
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| Series: | PLoS ONE |
| Online Access: | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19461962/?tool=EBI |
| _version_ | 1818744374410870784 |
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| author | Kelly P Nevin Byoung-Chan Kim Richard H Glaven Jessica P Johnson Trevor L Woodard Barbara A Methé Raymond J Didonato Sean F Covalla Ashley E Franks Anna Liu Derek R Lovley |
| author_facet | Kelly P Nevin Byoung-Chan Kim Richard H Glaven Jessica P Johnson Trevor L Woodard Barbara A Methé Raymond J Didonato Sean F Covalla Ashley E Franks Anna Liu Derek R Lovley |
| author_sort | Kelly P Nevin |
| collection | DOAJ |
| description | The mechanisms by which Geobacter sulfurreducens transfers electrons through relatively thick (>50 microm) biofilms to electrodes acting as a sole electron acceptor were investigated. Biofilms of Geobacter sulfurreducens were grown either in flow-through systems with graphite anodes as the electron acceptor or on the same graphite surface, but with fumarate as the sole electron acceptor. Fumarate-grown biofilms were not immediately capable of significant current production, suggesting substantial physiological differences from current-producing biofilms. Microarray analysis revealed 13 genes in current-harvesting biofilms that had significantly higher transcript levels. The greatest increases were for pilA, the gene immediately downstream of pilA, and the genes for two outer c-type membrane cytochromes, OmcB and OmcZ. Down-regulated genes included the genes for the outer-membrane c-type cytochromes, OmcS and OmcT. Results of quantitative RT-PCR of gene transcript levels during biofilm growth were consistent with microarray results. OmcZ and the outer-surface c-type cytochrome, OmcE, were more abundant and OmcS was less abundant in current-harvesting cells. Strains in which pilA, the gene immediately downstream from pilA, omcB, omcS, omcE, or omcZ was deleted demonstrated that only deletion of pilA or omcZ severely inhibited current production and biofilm formation in current-harvesting mode. In contrast, these gene deletions had no impact on biofilm formation on graphite surfaces when fumarate served as the electron acceptor. These results suggest that biofilms grown harvesting current are specifically poised for electron transfer to electrodes and that, in addition to pili, OmcZ is a key component in electron transfer through differentiated G. sulfurreducens biofilms to electrodes. |
| first_indexed | 2024-12-18T02:43:17Z |
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| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-18T02:43:17Z |
| publishDate | 2009-05-01 |
| publisher | Public Library of Science (PLoS) |
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| series | PLoS ONE |
| spelling | doaj.art-78b17e3d7bb74826ac165eea63e8cf9f2022-12-21T21:23:38ZengPublic Library of Science (PLoS)PLoS ONE1932-62032009-05-0145e562810.1371/journal.pone.0005628Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells.Kelly P NevinByoung-Chan KimRichard H GlavenJessica P JohnsonTrevor L WoodardBarbara A MethéRaymond J DidonatoSean F CovallaAshley E FranksAnna LiuDerek R LovleyThe mechanisms by which Geobacter sulfurreducens transfers electrons through relatively thick (>50 microm) biofilms to electrodes acting as a sole electron acceptor were investigated. Biofilms of Geobacter sulfurreducens were grown either in flow-through systems with graphite anodes as the electron acceptor or on the same graphite surface, but with fumarate as the sole electron acceptor. Fumarate-grown biofilms were not immediately capable of significant current production, suggesting substantial physiological differences from current-producing biofilms. Microarray analysis revealed 13 genes in current-harvesting biofilms that had significantly higher transcript levels. The greatest increases were for pilA, the gene immediately downstream of pilA, and the genes for two outer c-type membrane cytochromes, OmcB and OmcZ. Down-regulated genes included the genes for the outer-membrane c-type cytochromes, OmcS and OmcT. Results of quantitative RT-PCR of gene transcript levels during biofilm growth were consistent with microarray results. OmcZ and the outer-surface c-type cytochrome, OmcE, were more abundant and OmcS was less abundant in current-harvesting cells. Strains in which pilA, the gene immediately downstream from pilA, omcB, omcS, omcE, or omcZ was deleted demonstrated that only deletion of pilA or omcZ severely inhibited current production and biofilm formation in current-harvesting mode. In contrast, these gene deletions had no impact on biofilm formation on graphite surfaces when fumarate served as the electron acceptor. These results suggest that biofilms grown harvesting current are specifically poised for electron transfer to electrodes and that, in addition to pili, OmcZ is a key component in electron transfer through differentiated G. sulfurreducens biofilms to electrodes.https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19461962/?tool=EBI |
| spellingShingle | Kelly P Nevin Byoung-Chan Kim Richard H Glaven Jessica P Johnson Trevor L Woodard Barbara A Methé Raymond J Didonato Sean F Covalla Ashley E Franks Anna Liu Derek R Lovley Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. PLoS ONE |
| title | Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. |
| title_full | Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. |
| title_fullStr | Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. |
| title_full_unstemmed | Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. |
| title_short | Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. |
| title_sort | anode biofilm transcriptomics reveals outer surface components essential for high density current production in geobacter sulfurreducens fuel cells |
| url | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19461962/?tool=EBI |
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