Identification of a fourth gene involved in dTDP-rhamnose synthesis in Streptococcus mutans.
AUTOR(ES)
Tsukioka, Y
RESUMO
We had isolated three genes (rmlA, rmlB, and rmlC) involved in dTDP-rhamnose synthesis in Streptococcus mutans and found that three genes were insufficient for dTDP-rhamnose synthesis (Y. Tsukioka, Y. Yamashita, T. Oho, Y. Nakano, and T. Koga, J. Bacteriol. 179:1126-1134, 1997). The rmlD gene of S. mutans, encoding the enzyme which catalyzes the last step of dTDP-rhamnose synthesis, has been cloned and sequenced. The cell extract of Escherichia coli expressing the rmlD gene of S. mutans exhibited enzymatic activity corresponding to its counterpart in Shigella flexneri, a gram-negative bacterium. Rhamnose was not detected in the cell wall preparation purified from the mutant in which the cloned gene was insertionally inactivated. Rabbit antiserum against S. mutans serotype c-specific antigen did not react with autoclaved extracts from the mutant. The rmlD gene product of S. mutans compensated for the incompleteness of dTDP-rhamnose synthesis by the three previously isolated genes. These results indicate that the rmlD gene product is indispensable for the dTDP-rhamnose pathway and subsequently for the synthesis of serotype-specific antigen in S. mutans. Furthermore, conservation of the rmlD gene in Streptococcus species was demonstrated by Southern blot analysis.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=179269Documentos Relacionados
- Biological function of the dTDP-rhamnose synthesis pathway in Streptococcus mutans.
- Drug Targeting Mycobacterium tuberculosis Cell Wall Synthesis: Genetics of dTDP-Rhamnose Synthetic Enzymes and Development of a Microtiter Plate-Based Screen for Inhibitors of Conversion of dTDP-Glucose to dTDP-Rhamnose
- Formation of dTDP-Rhamnose Is Essential for Growth of Mycobacteria
- Recombination between gtfB and gtfC Is Required for Survival of a dTDP-Rhamnose Synthesis-Deficient Mutant of Streptococcus mutans in the Presence of Sucrose
- Identification and Functional Characterization of the Lactococcus lactis rfb Operon, Required for dTDP-Rhamnose Biosynthesis