A novel esterase from Bacillus subtilis (RRL 1789): purification and characterization of the enzyme.
An esterase (EC 3.1.1.1) produced by an isolated strain of Bacillus subtilis RRL 1789 exhibited moderate to high enantioselectivity in the kinetic resolution of several substrates like aryl carbinols, hydroxy esters, and halo esters. The enzyme named as B. subtilis esterase (BSE), was purified to >95% purity with a specific activity of 944 U/mg protein and 12% overall yield. The purified enzyme is approximately 52 kDa monomer, maximally activity at 37 degrees C and pH 8.0 and fairly stable up to 55 degrees C. The enzyme does not exhibit the phenomenon of interfacial activation with tributyrin and p-nitrophenyl butyrate beyond the saturation concentration. The enzyme showed preference for triacyglycerols and esters of p-nitrophenol with short chain fatty acid. Presence of Ca2+ ions increases the activity of enzyme by approximately 20% but its presence does not have any influence on the thermostability of the enzyme. The enzyme is not a metalloprotein and belongs to the family of serine proteases. The N-terminal amino acid sequence of BSE determined, as Met-Thr-Pro-Glu-Iso-Val-Thr-Thr-Glu-Tyr-Gly- revealed similarity with the N-terminal amino acid sequence of p-nitrobenzylesterase of B. subtilis.
Kaiser
Peerzada
P
Regional Research Laboratory, Canal Road, Jammu Tawi-180001, India.
Raina
Chand
C
Parshad
Rajinder
R
Johri
Sarojini
S
Verma
Vijeshwer
V
Andrabi
Khurshid I
KI
Qazi
Ghulam N
GN
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism; D004795:Enzyme Stability; D004950:Esterases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D013379:Substrate Specificity; D013696:Temperature
D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D008670:Metals; D004950:Esterases