This Article Full Text Full Text (PDF) An authors' corrections has been published Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Rolerson, E. Articles by Spatafora, G. Search for Related Content PubMed PubMed Citation Articles by Rolerson, E. Articles by Spatafora, G.

The SloR/Dlg Metalloregulator Modulates Streptococcus mutans Virulence Gene Expression

Department of Biology, Middlebury College, 276 Bicentennial Way, MBH354, Middlebury, Vermont 05753

Received 27 January 2006/ Accepted 17 April 2006

Metal ion availability in the human oral cavity plays a putative role in Streptococcus mutans virulence gene expression and in appropriate formation of the plaque biofilm. In this report, we present evidence that supports such a role for the DtxR-like SloR metalloregulator (called Dlg in our previous publications) in this oral pathogen. Specifically, the results of gel mobility shift assays revealed the sloABC, sloR, comDE, ropA, sod, and spaP promoters as targets of SloR binding. We confirmed differential expression of these genes in a GMS584 SloR-deficient mutant versus the UA159 wild-type progenitor by real-time semiquantitative reverse transcriptase PCR experiments. The results of additional expression studies support a role for SloR in S. mutans control of glucosyltransferases, glucan binding proteins, and genes relevant to antibiotic resistance. Phenotypic analysis of GMS584 revealed that it forms aberrant biofilms on an abiotic surface, is compromised for genetic competence, and demonstrates heightened incorporation of iron and manganese as well as resistance to oxidative stress compared to the wild type. Taken together, these findings support a role for SloR in S. mutans adherence, biofilm formation, genetic competence, metal ion homeostasis, oxidative stress tolerance, and antibiotic gene regulation, all of which contribute to S. mutans-induced disease.

This article has been cited by other articles:

• Kloosterman, T. G., Witwicki, R. M., van der Kooi-Pol, M. M., Bijlsma, J. J. E., Kuipers, O. P. (2008). Opposite Effects of Mn2+ and Zn2+ on PsaR-Mediated Expression of the Virulence Genes pcpA, prtA, and psaBCA of Streptococcus pneumoniae. J. Bacteriol. 190: 5382-5393 [Abstract] [Full Text]  
• Chong, P., Drake, L., Biswas, I. (2008). Modulation of covR Expression in Streptococcus mutans UA159. J. Bacteriol. 190: 4478-4488 [Abstract] [Full Text]  
• Dunning, D. W., McCall, L. W., Powell, W. F., Arscott, W. T., McConocha, E. M., McClurg, C. J., Goodman, S. D., Spatafora, G. A. (2008). SloR modulation of the Streptococcus mutans acid tolerance response involves the GcrR response regulator as an essential intermediary. Microbiology 154: 1132-1143 [Abstract] [Full Text]  
• Merritt, J., Zheng, L., Shi, W., Qi, F. (2007). Genetic characterization of the hdrRM operon: a novel high-cell-density-responsive regulator in Streptococcus mutans. Microbiology 153: 2765-2773 [Abstract] [Full Text]