Skip to content Skip to navigation
University of Warwick
  • Study
  • |
  • Research
  • |
  • Business
  • |
  • Alumni
  • |
  • News
  • |
  • About

University of Warwick
Publications service & WRAP

Highlight your research

  • WRAP
    • Home
    • Search WRAP
    • Browse by Warwick Author
    • Browse WRAP by Year
    • Browse WRAP by Subject
    • Browse WRAP by Department
    • Browse WRAP by Funder
    • Browse Theses by Department
  • Publications Service
    • Home
    • Search Publications Service
    • Browse by Warwick Author
    • Browse Publications service by Year
    • Browse Publications service by Subject
    • Browse Publications service by Department
    • Browse Publications service by Funder
  • Help & Advice
University of Warwick

The Library

  • Login
  • Admin

Tryptophan residues promote membrane association for a plant lipid glycosyltransferase involved in phosphate stress

Tools
- Tools
+ Tools

Ge, Changrong, Georgiev, Alexander, Öhman, Anders, Wieslander, A. and Kelly, Amélie A. (2011) Tryptophan residues promote membrane association for a plant lipid glycosyltransferase involved in phosphate stress. Journal of Biological Chemistry, Volume 286 (Number 8). pp. 6669-6684. doi:10.1074/jbc.M110.138495

Research output not available from this repository.

Request-a-Copy directly from author or use local Library Get it For Me service.

Official URL: http://dx.doi.org/10.1074/jbc.M110.138495

Request Changes to record.

Abstract

Chloroplast membranes contain a substantial excess of the nonbilayer-prone monogalactosyldiacylglycerol (GalDAG) over the biosynthetically consecutive, bilayer-forming digalactosyldiacylglycerol (GalGalDAG), yielding a high membrane curvature stress. During phosphate shortage, plants replace phospholipids with GalGalDAG to rescue phosphate while maintaining membrane homeostasis. Here we investigate how the activity of the corresponding glycosyltransferase (GT) in Arabidopsis thaliana (atDGD2) depends on local bilayer properties by analyzing structural and activity features of recombinant protein. Fold recognition and sequence analyses revealed a two-domain GT-B monotopic structure, present in other plant and bacterial glycolipid GTs, such as the major chloroplast GalGalDAG GT atDGD1. Modeling led to the identification of catalytically important residues in the active site of atDGD2 by site-directed mutagenesis. The DGD synthases share unique bilayer interface segments containing conserved tryptophan residues that are crucial for activity and for membrane association. More detailed localization studies and liposome binding analyses indicate differentiated anchor and substrate-binding functions for these separated enzyme interface regions. Anionic phospholipids, but not curvature-increasing nonbilayer lipids, strongly stimulate enzyme activity. From our studies, we propose a model for bilayer "control" of enzyme activity, where two tryptophan segments act as interface anchor points to keep the substrate region close to the membrane surface. Binding of the acceptor substrate is achieved by interaction of positive charges in a surface cluster of lysines, arginines, and histidines with the surrounding anionic phospholipids. The diminishing phospholipid fraction during phosphate shortage stress will then set the new GalGalDAG/phospholipid balance by decreasing stimulation of atDGD2.

Item Type: Journal Article
Subjects: Q Science > QK Botany
Q Science > QP Physiology
Divisions: Faculty of Science, Engineering and Medicine > Science > Life Sciences (2010- ) > Warwick HRI (2004-2010)
Library of Congress Subject Headings (LCSH): Tryptophan, Glycosyltransferases, Plant lipids, Escherichia coli, Bilayer lipid membranes, Phosphates, Arabidopsis thaliana
Journal or Publication Title: Journal of Biological Chemistry
Publisher: American Society for Biochemistry and Molecular Biology
ISSN: 0021-9258
Official Date: 25 February 2011
Dates:
DateEvent
25 February 2011Published
Volume: Volume 286
Number: Number 8
Page Range: pp. 6669-6684
DOI: 10.1074/jbc.M110.138495
Status: Peer Reviewed
Publication Status: Published
Access rights to Published version: Restricted or Subscription Access
Funder: Wenner-Gren Foundation, Kungl. Svenska vetenskapsakademien [Royal Swedish Academy of Science], Sixth Framework Programme (European Commission) (FP6), Sweden. Vetenskapsrådet [Research Council]

Data sourced from Thomson Reuters' Web of Knowledge

Request changes or add full text files to a record

Repository staff actions (login required)

View Item View Item
twitter

Email us: wrap@warwick.ac.uk
Contact Details
About Us