Biological functions of UDP-glucose synthesis in Streptococcus mutans

• Published in: Microbiology (Society for General Microbiology) Vol. 144; no. 5; pp. 1235 - 1245
• Main Authors: Yamashita, Yoshihisa, Tsukioka, Yuichi, Nakano, Yoshio, Tomihisa, Kiyotaka, Oho, Takahiko, Koga, Toshihiko
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.05.1998; Society for General Microbiology
• Subjects: Bacteriology; Base Sequence; Biological and medical sciences; Blotting, Southern; Chromatography, High Pressure Liquid; Cloning, Molecular; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; Genes, Bacterial; Hydrogen-Ion Concentration; Immunodiffusion; Metabolism. Enzymes; Microbiology; Molecular Sequence Data; Polysaccharides, Bacterial - analysis; Recombination, Genetic; Restriction Mapping; Sodium Chloride; Streptococcus mutans; Streptococcus mutans - genetics; Streptococcus mutans - growth & development; Streptococcus mutans - metabolism; Temperature; Uridine Diphosphate Glucose - biosynthesis; Uridine Diphosphate Glucose - physiology; UTP-Glucose-1-Phosphate Uridylyltransferase - genetics; UTP-Glucose-1-Phosphate Uridylyltransferase - metabolism; Nucleotide sequence; Enzyme; Transferases; Tolerance; Acidity; Gene expression; Streptococcus mutans; Streptococcaceae; Nucleotidyltransferases; Enzymatic activity; Bacteria; Micrococcales; UTP-glucose-1-phosphate uridylyltransferase; Aminoacid sequence
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/00221287-144-5-1235

Department of Preventive Dentistry, Kyushu University Faculty of Dentistry, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan ABSTRACT A gene encoding glucose-1-phosphate uridylyltransferase (EC 2.7.7.9 ) was isolated from Streptococcus mutans. A cell extract of Escherichia coli expressing the cloned gene exhibited glucose-1-phosphate uridylyltransferase activity. The enzyme catalyses the conversion of D-glucose 1-phosphate and UTP into UDP-D-glucose. Rabbit antiserum against the serotype-c-specific antigen did not react with autoclaved extracts from mutant cells in which the cloned gene was insertionally inactivated. The glucose content of the cell-wall preparation purified from the mutant was very much lowered, whereas there was no observable decrease in the content of rhamnose. When the mutant strain was grown in an acidic environment, its cell viability was much lower than that of the wild-type. These results suggest that UDP-D-glucose functions not only as an immediate precursor of the serotype-c-specific antigen of S. mutans (as a glucose donor for side-chain formation), but is also important for the organism's viability in environmental conditions of low pH. * Author for correspondence: Toshihiko Koga. Tel: +81 92 642 6350. Fax: +81 92 642 6354. e-mail: toshidha@mbox.nc.kyushu-u.ac.jp Keywords: Streptococcus mutans, UDP-glucose, glucose-1-phosphate uridylyltransferase, polysaccharide antigen, acid tolerance