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Lrs14 transcriptional regulators influence biofilm formation and cell motility of Crenarchaea.

ABSTRACT: Like bacteria, archaea predominately exist as biofilms in nature. However, the environmental cues and the molecular mechanisms driving archaeal biofilm development are not characterized. Here we provide data suggesting that the transcriptional regulators belonging to the Lrs14-like protein family constitute a key regulatory factor during Sulfolobus biofilm development. Among the six lrs14-like genes encoded by Sulfolobus acidocaldarius, the deletion of three led to markedly altered biofilm phenotypes. Although ?saci1223 and ?saci1242 deletion mutants were impaired in biofilm formation, the ?saci0446 deletion strain exhibited a highly increased extracellular polymeric substance (EPS) production, leading to a robust biofilm structure. Moreover, although the expression of the adhesive pili (aap) genes was upregulated, the genes of the motility structure, the archaellum (fla), were downregulated rendering the ?saci0446 strain non-motile. Gel shift assays confirmed that Saci0446 bound to the promoter regions of fla and aap thus controlling the expression of both cell surface structures. In addition, genetic epistasis analysis using ?saci0446 as background strain identified a gene cluster involved in the EPS biosynthetic pathway of S. acidocaldarius. These results provide insights into both the molecular mechanisms that govern biofilm formation in Crenarchaea and the functionality of the Lrs14-like proteins, an archaea-specific class of transcriptional regulators.

SUBMITTER: Orell A

PROVIDER: S-EPMC3965304 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Lrs14 transcriptional regulators influence biofilm formation and cell motility of Crenarchaea.

Orell Alvaro A Peeters Eveline E Vassen Victoria V Jachlewski Silke S Schalles Sven S Siebers Bettina B Albers Sonja-Verena SV

The ISME journal 20130509 10

Like bacteria, archaea predominately exist as biofilms in nature. However, the environmental cues and the molecular mechanisms driving archaeal biofilm development are not characterized. Here we provide data suggesting that the transcriptional regulators belonging to the Lrs14-like protein family constitute a key regulatory factor during Sulfolobus biofilm development. Among the six lrs14-like genes encoded by Sulfolobus acidocaldarius, the deletion of three led to markedly altered biofilm pheno ...[more]

PMID: 23657363

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Lrs14 transcriptional regulators influence biofilm formation and cell motility of Crenarchaea.

Publications

Lrs14 transcriptional regulators influence biofilm formation and cell motility of Crenarchaea.

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