Improved catalytic efficiency of a monomeric gamma-glutamyl transpeptidase from Bacillus licheniformis in presence of subtilisin.
Monomeric 30 kDa gamma-glutamyl transpeptidase (GGT(30)) was purified from culture broth of Bacillus licheniformis ER-15 along with a heterodimeric 67 kDa GGT (GGT(67)). In presence of subtilisin, GGT(30) had improved catalytic efficiency (V(max)/K(m)) of 59 min(-1), altered pH and temperature optima of pH 11 and 70 degrees C and had salt-tolerant glutaminase activity. Glutaminase activity was retained even in protease-inhibited condition in presence of 2 mM PMSF. GGT(30) and subtilisin complexation was also confirmed by relative electrophoretic mobility and fluorescence quenching experiment.
Tiwary
Ekta
E
Department of Microbiology, University of Delhi, South Campus, New Delhi 110021, India.
Gupta
Rani
R
D001407:Bacillus / Q000187:drug effects / Q000201:enzymology*; D002384:Catalysis; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects*; D020860:Subtilisin / Q000494:pharmacology*; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
D005723:gamma-Glutamyltransferase; D020860:Subtilisin