Record Details

The Cys78-Asn88 loop region of the Campylobacter jejuni CstII is essential for alpha 2,3-sialyltransferase activity: analysis of the His85 mutants

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title The Cys78-Asn88 loop region of the Campylobacter jejuni CstII is essential for alpha 2,3-sialyltransferase activity: analysis of the His85 mutants
 
Creator PRABHAKAR, PK
RAO, KK
BALAJIY, PV
 
Subject bifunctional
docking
flexibility
MD simulation
sialyltransferase
GANGLIOSIDE MIMICS
FLEXIBILITY
RECOGNITION
PROTEINS
SITE
GLYCOSYLTRANSFERASES
BIOSYNTHESIS
EVOLUTION
CATALYSIS
RESIDUES
 
Description CstII is a bifunctional sialyltransferase from Campylobacter jejuni that is active as a tetramer. CstIIs from different strains show substantial differences in enzyme activities (mono-versus bi-functional) and kinetic parameters. Crystal structures of CstII show that His85, conserved in CstIIs from different strains is part of an 11-residue loop that abuts the extended acceptor-binding site and is also part of the subunit interface. In this study, the role of His85 in the activity of CstII has been investigated by mutating it to Ala, Phe, Trp or Tyr. His85 is found to be essential for alpha 2,3-sialyltransferase activity but not alpha 2,8-sialyltransferase activity. Although no gross changes are observed in secondary and tertiary structures, thermal stability is affected by His85 mutation. MD simulations show changes in the flexibility of the loop regions including those in the binding site.
 
Publisher OXFORD UNIV PRESS
 
Date 2014-12-28T15:08:25Z
2014-12-28T15:08:25Z
2014
 
Type Article
 
Identifier JOURNAL OF BIOCHEMISTRY, 156(4)229-238
0021-924X
1756-2651
http://dx.doi.org/10.1093/jb/mvu033
http://dspace.library.iitb.ac.in/jspui/handle/100/16833
 
Language English