1kas
From Proteopedia
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
| - | In the biosynthesis of fatty acids, the beta-ketoacyl-acyl carrier protein | + | In the biosynthesis of fatty acids, the beta-ketoacyl-acyl carrier protein (ACP) synthases catalyze chain elongation by the addition of two-carbon units derived from malonyl-ACP to an acyl group bound to either ACP or CoA. The crystal structure of beta-ketoacyl synthase II from Escherichia coli has been determined with the multiple isomorphous replacement method and refined at 2.4 A resolution. The subunit consists of two mixed five-stranded beta-sheets surrounded by alpha-helices. The two sheets are packed against each other in such a way that the fold can be described as consisting of five layers, alpha-beta-alpha-beta-alpha. The enzyme is a homodimer, and the subunits are related by a crystallographic 2-fold axis. The two active sites are located near the dimer interface but are approximately 25 A apart. The proposed nucleophile in the reaction, Cys163, is located at the bottom of a mainly hydrophobic pocket which is also lined with several conserved polar residues. In spite of very low overall sequence homology, the structure of beta-ketoacyl synthase is similar to that of thiolase, an enzyme involved in the beta-oxidation pathway, indicating that both enzymes might have a common ancestor. |
==About this Structure== | ==About this Structure== | ||
| Line 29: | Line 29: | ||
[[Category: lipid metabolism]] | [[Category: lipid metabolism]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:32:04 2008'' |
Revision as of 11:32, 21 February 2008
|
BETA-KETOACYL-ACP SYNTHASE II FROM ESCHERICHIA COLI
Overview
In the biosynthesis of fatty acids, the beta-ketoacyl-acyl carrier protein (ACP) synthases catalyze chain elongation by the addition of two-carbon units derived from malonyl-ACP to an acyl group bound to either ACP or CoA. The crystal structure of beta-ketoacyl synthase II from Escherichia coli has been determined with the multiple isomorphous replacement method and refined at 2.4 A resolution. The subunit consists of two mixed five-stranded beta-sheets surrounded by alpha-helices. The two sheets are packed against each other in such a way that the fold can be described as consisting of five layers, alpha-beta-alpha-beta-alpha. The enzyme is a homodimer, and the subunits are related by a crystallographic 2-fold axis. The two active sites are located near the dimer interface but are approximately 25 A apart. The proposed nucleophile in the reaction, Cys163, is located at the bottom of a mainly hydrophobic pocket which is also lined with several conserved polar residues. In spite of very low overall sequence homology, the structure of beta-ketoacyl synthase is similar to that of thiolase, an enzyme involved in the beta-oxidation pathway, indicating that both enzymes might have a common ancestor.
About this Structure
1KAS is a Single protein structure of sequence from Escherichia coli. The following page contains interesting information on the relation of 1KAS with [Fatty Acid Synthase]. Active as Beta-ketoacyl-acyl-carrier-protein synthase I, with EC number 2.3.1.41 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Crystal structure of beta-ketoacyl-acyl carrier protein synthase II from E.coli reveals the molecular architecture of condensing enzymes., Huang W, Jia J, Edwards P, Dehesh K, Schneider G, Lindqvist Y, EMBO J. 1998 Mar 2;17(5):1183-91. PMID:9482715
Page seeded by OCA on Thu Feb 21 13:32:04 2008
Categories: Beta-ketoacyl-acyl-carrier-protein synthase I | Escherichia coli | Fatty Acid Synthase | Single protein | Dehesh, K. | Edwards, P. | Huang, W. | Jia, J. | Lindqvist, Y. | Schneider, G. | Acyltransferase | Alpha-beta protein | Alpha-beta-alpha-beta-alpha | Condensing enzyme | Fatty acid elongation | Five-layered fold | Lipid metabolism
