The long range goal of this proposal is to understand the mechanism of catabolite repression which effects and controls carbohydrate utilization in Streptococcus mu tans and how this process is involved in the pathogenesis of S. mutans-induced dental caries. The mechanism of catabolite repression is not understood in Gram positive bacteria and elucidation of this process will potentially allow better prevention of dental caries. However, this long range goal can not be achieved without first attaining a basic understanding of the local regulation of the phosphoenolpyruvate-dependent phosphotransferase system (PTS) Of carbohydrate transport in S. mutans. Therefore, the short term goal of this proposal is to initiate studies into the regulation of the S. mutans PTS. The individual specific aims of this proposal include: 1.) isolation and cloning in E. coli K12 of S. mutans gene clusters involved in the transport and utilization of various carbohydrates via the PTS; 2.) identification of the gene products of the isolated PTS gene clusters by in vitro gene expression systems; 3.) determination of the nucleotide sequences of the isolated PTS gene clusters to determine the overall operon structures, to identify regions for the in vitro generation of transcriptional and translational fusions, and to identify putative regulatory control regions; 4.) in vitro generation of transcriptional fusions to monitor regulation of the S. mutans PTS in response to various carbohydrates; 5.) analysis of the putative promoter regions of the isolated PTS gene clusters and identification and analysis of putative control regions involved with regulation of these operons using translational fusions; and 6.) assay of transcriptional activity of the S. mutans PTS catabolic enzyme genes under various environmental conditions. Accomplishment of these specific aims will provide the necessary information to initiate studies into the long range goal and will be paramount to understanding carbohydrate utilization and regulation of this process in Streptococcus mutans.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
7R29DE010890-04
Application #
2518124
Study Section
Oral Biology and Medicine Subcommittee 1 (OBM)
Project Start
1994-09-01
Project End
1999-08-31
Budget Start
1997-09-01
Budget End
1998-08-31
Support Year
4
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of South Florida
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
City
Tampa
State
FL
Country
United States
Zip Code
33612
Honeyman, A L; Curtiss 3rd, R (2000) The mannitol-specific enzyme II (mtlA) gene and the mtlR gene of the PTS of Streptococcus mutans. Microbiology 146 ( Pt 7):1565-72
Cote, C K; Cvitkovitch, D; Bleiweis, A S et al. (2000) A novel beta-glucoside-specific PTS locus from Streptococcus mutans that is not inhibited by glucose. Microbiology 146 ( Pt 7):1555-63