Evolutionary stability of DNA uptake signal sequences in the Pasteurellaceae.

ABSTRACT: The DNA-uptake signal sequence (USS) of the bacterium Haemophilus influenzae is highly over-represented in its genome (1,471 copies of the core sequence AAGTGCGGT), and DNA fragments containing USS are preferentially taken up by competent cells. Because this bias favors uptake of conspecific DNA, USSs are often considered a kind of mate recognition system in bacteria, acting as species-specific barriers against uptake of unrelated DNA. However, the H. influenzae USS is highly over-represented in the genomes of three otherwise-divergent Pasteurellaceae species (Pasteurella multocida, Haemophilus somnus, and Actinobacillus actinomycetemcomitans, 927, 1,205, and 1,760 copies, respectively), suggesting that USSs do not always limit exchange. USSs in all these genomes are mainly in coding regio

SUBMITTER: Bakkali M 

PROVIDER: S-EPMC384778 | biostudies-literature | 2004 Mar

REPOSITORIES: biostudies-literature