Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

E coli MG1655 biofilm and planktonic gene expression

ABSTRACT: Bacteria growing as surface-adherent biofilms are better able to withstand chemical and physical stresses than their unattached, planktonic counterparts. Using transcriptional profiling and quantitative PCR, we observed a previously uncharacterized gene, yjfO, to be upregulated during Escherichia coli MG1655 biofilm growth in a chemostat on serine-limited defined medium. A yjfO mutant, developed through targeted insertion mutagenesis, and a yjfO-complemented strain, were obtained for further characterization. While bacterial surface colonization levels (CFU/cm2) were similar in all three strains, the mutant strain exhibited reduced microcolony formation when observed in flow cells, and greatly enhanced flagellar motility on soft (0.3%) agar. Complementation of yjfO restored microcolony formation and flagellar motility to wild type levels. Cell surface hydrophobicity and twitching motility were unaffected by the presence or absence of yjfO. In contrast to the parent strain, biofilms from the mutant strain were less able to resist acid and peroxide stresses. yjfO had no significant effect on E. coli biofilm susceptibility to alkali or heat stress. Planktonic cultures from all three strains showed similar responses to these stresses. Regardless of the presence of yjfO, planktonic E. coli withstood alkali stress better than biofilm populations. Complementation of yjfO restored viability following exposure to peroxide stress, but did not restore acid resistance. Based on its influence on biofilm formation, stress response, and effects on motility, we propose renaming the uncharacterized gene, yjfO, as bsmA (biofilm stress and motility). Transcriptional profiling of duplicate biofilm and planktonic cultures of E. coli MG1655 grown in serine-limited MOPS minimal media.

ORGANISM(S): Escherichia coli

SUBMITTER: Robert McLean

PROVIDER: E-GEOD-18362 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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A previously uncharacterized gene, yjfO (bsmA), influences Escherichia coli biofilm formation and stress response.

Weber Mary M MM French Christa L CL Barnes Mary B MB Siegele Deborah A DA McLean Robert J C RJC

Microbiology (Reading, England) 20091015 Pt 1

Bacteria growing as surface-adherent biofilms are better able to withstand chemical and physical stresses than their unattached, planktonic counterparts. Using transcriptional profiling and quantitative PCR, we observed a previously uncharacterized gene, yjfO to be upregulated during Escherichia coli MG1655 biofilm growth in a chemostat on serine-limited defined medium. A yjfO mutant, developed through targeted-insertion mutagenesis, and a yjfO-complemented strain, were obtained for further char ...[more]

PMID: 19833773

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Dataset Information

E coli MG1655 biofilm and planktonic gene expression

Publications

A previously uncharacterized gene, yjfO (bsmA), influences Escherichia coli biofilm formation and stress response.

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