Current Proteomics

Bernd Rehm  
Institute of Molecular BioSciences Massey University
Private Bag 11222
Palmerston North
New Zealand

Back

B-factor Analysis and Conformational Rearrangement of Aldose Reductase

Author(s): Ganesaratnam K. Balendiran, J. Rajendran Pandian, Evin Drake, Anubhav Vinayak, Malkhey Verma, Duilio Cascio.

Graphical Abstract:


Abstract:

The NADPH-dependent reduction of glucose reaction that is catalyzed by Aldose Reductase (AR) follows a sequential ordered kinetic mechanism in which the co-factor NADPH binds to the enzyme prior to the aldehyde substrate. The kinetic/structural experiments have found a conformational change involving a hinge-like movement of a surface loop (residues 213-224) which is anticipated to take place upon the binding of the diphosphate moiety of NADPH. The reorientation of this loop, expected to permit the release of NADP+, represents the rate-limiting step of the catalytic mechanism. This study reveals: 1) The Translation/Libration/Screw (TLS) analysis of absolute B-factors of apo AR crystal structures indicates that the 212-224 loop might move as a rigid group. 2) Residues that make the flexible loop slide in the AR binary and ternary complexes. 3) The normalized B-factors separate this segment into three differnt clusters with fewer residues.

Keywords: Aldo-keto reductase, B-factor, clustering, crystal structure, statistical analysis, structural dynamics, TLS.

Order Reprints Order Eprints Rights & PermissionsPrintExport

Article Details

VOLUME: 11
ISSUE: 3
Year: 2014
Page: [151 - 160]
Pages: 10
DOI: 10.2174/157016461103140922163444