Record Details

Chemical modification of 3-HBA-6-hydroxylase by phenylglyoxal: Kinetic acid physicochemical studies on the modified enzyme

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Chemical modification of 3-HBA-6-hydroxylase by phenylglyoxal: Kinetic acid physicochemical studies on the modified enzyme
 
Creator SUMATHI, S
DASGUPTA, D
VAIDYANATHAN, CS
 
Subject para-hydroxybenzoate hydroxylase
cepacia 3-hydroxybenzoate 6-hydroxylase
pseudomonas-fluorescens
arginine residues
tertiary structure
purification
substrate
binding
reagents
sequence
 
Description The inactivation of 3-HBA-6-hydroxylase isolated from Micrococcus species by phenylglyoxal and protection offered by 3-HBA against inactivation indicate the presence of arginine residue at or near the substrate binding site. The loss of enzyme activity was time and concentration dependent and displayed pseudo-first order kinetics. a 'n' value of 0.9 was obtained thus suggesting the modification of a single arginine residue per active site which led to the loss of enzyme activity. The enzyme activity could be restored by extensive dialysis at neutral pH. Quenching of the intrinsic fluorescence and reduction in the ellipticity value at 280 nm in the near-UV CD spectrum of the enzyme was noticed after its treatment with phenylglyoxal. These observations probably imply distinct perturbations in the environment of adjacent aromatic amino acid residues such as tryptophan as a consequence of arginine modification.
 
Publisher NATL INST SCIENCE COMMUNICATION
 
Date 2011-08-19T03:55:05Z
2011-12-26T12:56:02Z
2011-12-27T05:44:09Z
2011-08-19T03:55:05Z
2011-12-26T12:56:02Z
2011-12-27T05:44:09Z
1998
 
Type Article
 
Identifier INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS, 35(5), 266-272
0301-1208
http://dspace.library.iitb.ac.in/xmlui/handle/10054/10216
http://hdl.handle.net/10054/10216
 
Language en