PHYTONUTRIENT BIOCHEMISTRY, PHYSIOLOGY, AND TRANSPORT
Location: Children Nutrition Research Center (Houston, Tx)
Title: Purification, crystallization and preliminary X-ray analysis of an "Arabidopsis" Chloroplastic Glutaredoxin
| Li, Lenong - SAMUEL ROBERTS NOBLE FOUN |
| Cheng, Ning-Hui - BAYLOR COLLEGE MED |
| Wang, Xiaoqiang - SAMUEL ROBERTS NOBLE FOUN |
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 8, 2007
Publication Date: July 21, 2007
Citation: Li, L., Cheng, N-H., Wang, X. 2007. Purification, crystallization and preliminary X-ray analysis on an "Arabidopsis" Chloroplastic Glutaredoxin [abstract]. American Crystallographic Association, Inc., Proceeding of the 2007 Meeting of the American Crystallographic Association, July 21-26, 2007, Salt Lake, Utah. TP093, p. 113.
Glutaredoxins (Grxs) are ubiquitous small heat-stable disulfide oxidoreductases and catalyze the reduction of protein disulfides and of glutathione (GSH)-protein mixed disulfides via a dithiol or monothiol mechanism. Grxs are involved in many cellular processes and play important roles in protecting cells against oxidative stresses. In plants, there are a large Grx gene family, but only a few have been studied. AtGRXcp from "Arabidopsis thaliana" was identified as a member of the monothiol Grxs, contains a conserved putative active motif "CGFS", and may protect plant cells against protein oxidative damage. The AtGRXcp gene was cloned into pET-41a (+) vector and expressed in "E. coli" strain BL21 (DE3). The protein was purified to homogeneity using a GraviTrap affinity column and superdex 75 column, and the GST tag was cleaved by incubation with enterokinase. Crystallization screens were carried out by hanging-drop vapor diffusion method at 20°C, and crystals were obtained in 0.1 "M" MES pH 6.5, 1.6 "M" ammonium sulfate, and 10% dioxane. X-ray analysis and structural determination are in progress. The structural study of AtGRXcp may provide a basis to understand the structure-function relationships within this class of enzymes, and elucidate the mechanism of protecting protein oxidation during plant stress conditions.