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High-frequency conjugation system facilitates biofilm formation and pAMbeta1 transmission by Lactococcus lactis.

ABSTRACT: The importance of conjugation as a mechanism to spread biofilm determinants among microbial populations was illustrated with the gram-positive bacterium Lactococcus lactis. Conjugation triggered the enhanced expression of the clumping protein CluA, which is a main biofilm attribute in lactococci. Clumping transconjugants further transmitted the biofilm-forming elements among the lactococcal population at a much higher frequency than the parental non-clumping donor. This cell-clumping-associated high-frequency conjugation system also appeared to serve as an internal enhancer facilitating the dissemination of the broad-host-range drug resistance gene-encoding plasmid pAMbeta1 within L. lactis, at frequencies more than 10,000 times higher than those for the non-clumping parental donor strain. The implications of this finding for antibiotic resistance gene dissemination are discussed.

SUBMITTER: Luo H

PROVIDER: S-EPMC1151824 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature

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High-frequency conjugation system facilitates biofilm formation and pAMbeta1 transmission by Lactococcus lactis.

Luo Hongliang H Wan Kai K Wang Hua H HH

Applied and environmental microbiology 20050601 6

The importance of conjugation as a mechanism to spread biofilm determinants among microbial populations was illustrated with the gram-positive bacterium Lactococcus lactis. Conjugation triggered the enhanced expression of the clumping protein CluA, which is a main biofilm attribute in lactococci. Clumping transconjugants further transmitted the biofilm-forming elements among the lactococcal population at a much higher frequency than the parental non-clumping donor. This cell-clumping-associated ...[more]

PMID: 15932992

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