Purification and characterization of an esterase from Acinetobacter lwoffii I6C-1.
EstA was purified from the supernatant by A. lwoffii 16C-1. Its molecular mass was determined to be 45 kDa, and the optimal activity occurred when the pH level was 8.0 at a temperature of 37 degrees C. The activation energies for the hydrolysis of p-nitrophenyl butyrate was determined to be 11.25 kcal/mol in the temperature range of 10-37 degrees C. The enzyme was unstable at temperatures higher than 50 degrees C. The Michaelis constant ( K(m)) and V(max) for p-nitrophenyl butyrate were 11 mocroM and 131.6 mocroM min(-1) mg of protein-1, respectively. The enzyme was strongly inhibited by Hg(2-), Ca(2+), Mg(2+), Fe(2+), Cu(2+), Zn(2+), Mn(2+), Co(2+), ethylemediaminetetraacetic acid (EDTA), phenylmethylsulfonyl fluoride (PMSF), and diisopropyl fluorophosphate (DFP).
Kim
Hye Eun
HE
Dept. of Microbiology, Han Nam University, 133 Ojung-dong, Taeduk-ku, Taejon, 306-791 Korea.
Park
Kyeong Ryang
KR
D000150:Acinetobacter / Q000201:enzymology*; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008970:Molecular Weight; D013816:Thermodynamics
D004791:Enzyme Inhibitors; C019724:arginine esterase; D002265:Carboxylic Ester Hydrolases