Please use this identifier to cite or link to this item:
Title: Crystal structure of the acyltransferase domain of the iterative polyketide synthase in enediyne biosynthesis
Authors: Liew, Chong Wai
Nilsson, Martina
Chen, Ming Wei
Sun, Huihua
Cornvik, Tobias Carl
Liang, Zhao-Xun
Lescar, Julien
Keywords: DRNTU::Science::Biological sciences
Issue Date: 2012
Source: Liew, C. W., Nilsson, M., Chen, M. W., Sun, H., Cornvik, T. C., Liang, Z.-X. et al. (2012). Crystal structure of the acyltransferase domain of the iterative polyketide synthase in enediyne biosynthesis. The journal of biological chemistry, 287, 23203-23215.
Series/Report no.: The journal of biological chemistry
Abstract: Biosynthesis of the enediyne natural product dynemicin in Micromonospora chersina is initiated by DynE8, a highly reducing iterative type I polyketide synthase that assembles polyketide intermediates from the acetate units derived solely from malonyl-CoA. To understand the substrate specificity and the evolutionary relationship between the acyltransferase (AT) domains of DynE8, fatty acid synthase, and modular polyketide synthases, we overexpressed a 44-kDa fragment of DynE8 (hereafter named ATDYN10) encompassing its entire AT domain and the adjacent linker domain. The crystal structure at 1.4 Å resolution unveils a α/β hydrolase and a ferredoxin-like subdomain with the Ser-His catalytic dyad located in the cleft between the two subdomains. The linker domain also adopts a α/β fold abutting the AT catalytic domain. Co-crystallization with malonyl-CoA yielded a malonyl-enzyme covalent complex that most likely represents the acyl-enzyme intermediate. The structure explains the preference for malonyl-CoA with a conserved arginine orienting the carboxylate group of malonate and several nonpolar residues that preclude α-alkyl malonyl-CoA binding. Co-crystallization with acetyl-CoA revealed two noncovalently bound acetates generated by the enzymatic hydrolysis of acetyl-CoA that acts as an inhibitor for DynE8. This suggests that the AT domain can upload the acyl groups from either malonyl-CoA or acetyl-CoA onto the catalytic Ser651 residue. However, although the malonyl group can be transferred to the acyl carrier protein domain, transfer of the acetyl group to the acyl carrier protein domain is suppressed. Local structural differences may account for the different stability of the acyl-enzyme intermediates.
DOI: 10.1074/jbc.M112.362210
Fulltext Permission: none
Fulltext Availability: No Fulltext
Appears in Collections:SBS Journal Articles

Citations 10

Updated on Mar 3, 2021

Citations 10

Updated on Mar 7, 2021

Page view(s) 20

Updated on Apr 15, 2021

Google ScholarTM




Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.