Kinetic characterization of arginine deiminase and carbamate kinase from Streptococcus pyogenes M49.
Protein Expr Purif
; 91(1): 61-8, 2013 Sep.
Article
en En
| MEDLINE
| ID: mdl-23867361
ABSTRACT
Streptococcus pyogenes (group A Streptococcus, GAS) is an important human pathogen causing mild superficial infections of skin and mucous membranes, but also life-threatening systemic diseases. S. pyogenes and other prokaryotic organisms use the arginine deiminase system (ADS) for survival in acidic environments. In this study, the arginine deiminase (AD), and carbamate kinase (CK) from S. pyogenes M49 strain 591 were heterologously expressed in Escherichia coli DH5α, purified, and kinetically characterized. AD and CK from S. pyogenes M49 share high amino acid sequence similarity with the respective enzymes from Lactococcus lactis subsp. lactis IL1403 (45.6% and 53.5% identical amino acids) and Enterococcus faecalis V583 (66.8% and 66.8% identical amino acids). We found that the arginine deiminase of S. pyogenes is not allosterically regulated by the intermediates and products of the arginine degradation (e.g., ATP, citrulline, carbamoyl phosphate). The Km and Vmax values for arginine were 1.13±0.12mM (mean±SD) and 1.51±0.07µmol/min/mg protein. The carbamate kinase is inhibited by ATP but unaffected by arginine and citrulline. The Km and Vmax values for ADP were 0.72±0.08mM and 1.10±0.10µmol/min/mg protein and the Km for carbamoyl phosphate was 0.65±0.07mM. The optimum pH and temperature for both enzymes were 6.5 and 37°C, respectively.
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Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Streptococcus pyogenes
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Proteínas Recombinantes
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Fosfotransferasas (aceptor de Grupo Carboxilo)
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Hidrolasas
Idioma:
En
Revista:
Protein Expr Purif
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2013
Tipo del documento:
Article
País de afiliación:
Alemania