Characterization of CMP-N-acetylneuraminic acid synthetase of group B streptococci
| Autor: | Rachel F. Haft, Michael R. Wessels |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Cytidine Triphosphate
Biology Neisseria meningitidis medicine.disease_cause Microbiology Streptococcus agalactiae chemistry.chemical_compound Biosynthesis medicine Escherichia coli Serotyping Molecular Biology chemistry.chemical_classification N-Acylneuraminate Cytidylyltransferase Streptococcus N-acylneuraminate cytidylyltransferase N-Acetylneuraminic Acid Sialic acid Enzyme chemistry Biochemistry Sialic Acids N-Acetylneuraminic acid Research Article |
| Zdroj: | Journal of bacteriology. 176(23) |
| ISSN: | 0021-9193 |
| Popis: | The capsular polysaccharide is a critical virulence factor for group B streptococci associated with human infections, yet little is known about capsule biosynthesis. We detected CMP-Neu5Ac synthetase, the enzyme which activates N-acetylneuraminic acid (Neu5Ac, or sialic acid) for transfer to the nascent capsular polysaccharide, in multiple group B streptococcus serotypes, all of which elaborate capsules containing Neu5Ac. CMP-Neu5Ac synthetase isolated from a high-producing type Ib strain was purified 87-fold. The enzyme had apparent Km values of 7.6 for Neu5Ac and 1.4 for CTP and a pH optimum of 8.3 to 9.4, required magnesium, and was stimulated by dithiothreitol. This is the first characterization of an enzyme involved in group B streptococcus capsular polysaccharide biosynthesis. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|