Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Transcription profiling of Actinobacillus pleuropneumoniae wild type, hns mutants and rseA mutants

ABSTRACT: Clinical isolates of the porcine pathogen Actinobacillus pleuropneumoniae often form adherent colonies on agar plates due to expression of an operon, pgaABCD, encoding a poly-N-acetylglucosamine (PGA) extracellular matrix. The adherent colony phenotype, which correlates with the ability to form a biofilm on the surface of polystyrene plates, is lost following serial passage in broth culture, and repeated passage of the non-adherent variants on solid media does not result in reversion to the adherent colony phenotype. In order to investigate the regulation of PGA expression and biofilm formation in A. pleuropneumoniae, we screened a bank of transposon mutants of the non-adherent serovar 1 strain, S4074T, and identified mutations in two genes, rseA and hns, which resulted in formation of the adherent colony phenotype. In other bacteria, including the Enterobacteriaceae, H-NS acts as a global gene regulator, and RseA is a negative regulator of the extracytoplasmic stress response sigma factor, ?E. Transcription profiling of A. pleuropneumoniae rseA and hns mutants revealed that both ?E and H-NS independently regulate expression of the pga operon. Transcription of the pga operon is initiated from a ?E promoter site in the absence of H-NS, and up-regulation of ?E is sufficient to displace H-NS, allowing transcription to proceed. In A. pleuropneumoniae, H-NS does not act as a global gene regulator, but rather specifically regulates biofilm formation via repression of the pga operon. Positive regulation of the pga operon by ?E indicates that biofilm formation in is part of the extracytoplasmic stress response in A. pleuropneumoniae.

ORGANISM(S): Actinobacillus pleuropneumoniae

SUBMITTER: Ming-Shi Li

PROVIDER: E-MEXP-2461 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Regulation of pga operon expression and biofilm formation in Actinobacillus pleuropneumoniae by sigmaE and H-NS.

Bossé Janine T JT Sinha Sunita S Li Ming-Shi MS O'Dwyer Clíona A CA Nash John H E JH Rycroft Andrew N AN Kroll J Simon JS Langford Paul R PR

Journal of bacteriology 20100305 9

Clinical isolates of the porcine pathogen Actinobacillus pleuropneumoniae often form adherent colonies on agar plates due to expression of an operon, pgaABCD, encoding a poly-beta-1,6-N-acetyl-D-glucosamine (PGA) extracellular matrix. The adherent colony phenotype, which correlates with the ability to form biofilms on the surfaces of polystyrene plates, is lost following serial passage in broth culture, and repeated passage of the nonadherent variants on solid media does not result in reversion ...[more]

PMID: 20207760

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Dataset Information

Transcription profiling of Actinobacillus pleuropneumoniae wild type, hns mutants and rseA mutants

Publications

Regulation of pga operon expression and biofilm formation in Actinobacillus pleuropneumoniae by sigmaE and H-NS.

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