Regulation of gene expression in a mixed-genus community: stabilized arginine biosynthesis in Streptococcus gordonii by coaggregation with Actinomyces naeslundii.

ABSTRACT: Interactions involving genetically distinct bacteria, for example, between oral streptococci and actinomyces, are central to dental plaque development. A DNA microarray identified Streptococcus gordonii genes regulated in response to coaggregation with Actinomyces naeslundii. The expression of 23 genes changed >3-fold in coaggregates, including that of 9 genes involved in arginine biosynthesis and transport. The capacity of S. gordonii to synthesize arginine was assessed using a chemically defined growth medium. In monoculture, streptococcal arginine biosynthesis was inefficient and streptococci could not grow aerobically at low arginine concentrations. In dual-species cultures containing coaggregates, however, S. gordonii grew to high cell density at low arginine concentrations. Equivalen

SUBMITTER: Jakubovics NS 

PROVIDER: S-EPMC2395002 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature