NanA, a neuraminidase from Streptococcus pneumoniae, shows high levels of sequence diversity, at least in part through recombination with Streptococcus oralis.

ABSTRACT: Streptococcus pneumoniae, an important human pathogen, contains at least two genes, nanA and nanB, that express sialidase activity. NanA is a virulence determinant of pneumococci which is important in animal models of colonization and middle ear infections. The gene encoding NanA was detected in all 106 pneumococcal strains screened that represented 59 restriction profiles. Sequencing confirmed a high level of diversity, up to 17.2% at the nucleotide level and 14.8% at the amino acid level. NanA diversity is due to a number of mechanisms including insertions, point mutations, and recombination generating mosaic genes. The level of nucleotide divergence for each recombinant block is greater than 30% and much higher than the 20% identified within mosaic pbp genes, suggesting that a high sele

SUBMITTER: King SJ 

PROVIDER: S-EPMC1196044 | biostudies-literature | 2005 Aug

REPOSITORIES: biostudies-literature