INVESTIGADORES
MOLLERACH Marta Eugenia
artículos
Título:
Biochemical characterization of the Glucose 1-Phosphate Uridylyltransferase (GalU) essential for capsule biosynthesis.
Autor/es:
BONOFIGLIO L; GARCÍA E; MOLLERACH M
Revista:
CURRENT MICROBIOLOGY
Editorial:
Springer Science
Referencias:
Año: 2005 vol. 51 p. 217 - 221
ISSN:
0343-8651
Resumen:
The glucose 1-phosphate uridylyltransferase (GalU) is absolutely required for the biosynthesis of capsular polysaccharide, the sine qua non virulence factor of Streptococcus pneumoniae. The pneumococcal GalU protein was overexpressed in Escherichia coli, and purified. GalU showed a pI of 4.23, and catalyzed the reversible formation of UDP-glucose and pyrophosphate from UTP and glucose 1-phosphate with Km values of 0.4 mM for UDP-glucose, 0.26 mM for pyrophosphate, 0.19 mM for glucose 1-phosphate, and 0.24 mM for UTP. GalU has an optimum pH of 88.5, and requires Mg2+ for activity. Neither ADP-glucose nor TDP-glucose is utilized as substrates in vitro. The purification of GalU represents a fundamental step to provide insights on drug design to control the biosynthesis of the main pneumococcal virulence factor.