Substrate recognition and selectivity of plant glycerol-3-phosphate acyltransferases (GPATs) from Cucurbita moscata and Spinacea oleracea.
Tamada, T., Feese, M.D., Ferri, S.R., Kato, Y., Yajima, R., Toguri, T., Kuroki, R.(2004) Acta Crystallogr D Biol Crystallogr 60: 13-21
- PubMed: 14684887
- DOI: https://doi.org/10.1107/s0907444903020778
- Primary Citation of Related Structures:
1IUQ - PubMed Abstract:
Stromal glycerol-3-phosphate acyltransferases (GPAT) are responsible for the selective incorporation of saturated and unsaturated fatty-acyl chains into chloroplast membranes, which is an important determinant of a plant's ability to tolerate chilling temperatures. The molecular mechanisms of plant chilling tolerance were elucidated by creating chimeric GPATs between squash (Cucurbita moscata, chilling-sensitive) and spinach (Spinacea oleracea, chilling-tolerant) and the results were interpreted using structural information on squash GPAT determined by X-ray crystallography at 1.55 A resolution. Enzymatic analysis of the chimeric GPATs showed that the chimeric GPATs containing the spinach region from residues 128 to 187 prefer the 18:1 unsaturated fatty acid rather than 16:0 saturated fatty acid. Structure analysis suggests that the size and character of the cavity that is formed from this region determines the specific recognition of acyl chains.
Organizational Affiliation:
Central Laboratories for Key Technology, Kirin Brewery Co. Ltd, Fukuura 1-13-5, Kanazawa-ku, Yokohama 236-0004, Japan.