Scientists have strongly suspected that the tooth decay-causing bacterium Streptococcus mutans modifies certain aspects of its behavior through a 2-component signaling network called vicRK. The first protein component initiates a signal on S. mutans’ cell surface; the second component thereafter receives and processes the message, then relays it accordingly to the cytoplasm for an appropriate response. Left unanswered is which type of adaptive behavior the network actually triggers. In the June issue of the Journal of Bacteriology, National Institute of Dental and Craniofacial Research (NIDCR) grantees and colleagues provide the answer. The authors, Senadheera, et al, report that the vicRK network regulates the bacterium’s sucrose-mediated adhesion to tooth enamel, a vital early step in the process that leads to tooth decay. The network also seems to regulate the ex-pression of genes involved in the expression of other virulence factors, although additional research will be needed to define better which genes are involved. As the authors noted, these data could provide valuable molecular targets to more effectively control this destructive oral bacterium.
(Source: nidcr.nih.gov; Science News in Brief, accessed July 1, 2005)
