Back to Search Start Over

FabQ, a Dual-Function Dehydratase/Isomerase, Circumvents the Last Step of the Classical Fatty Acid Synthesis Cycle

Authors :
Hongkai Bi
Haihong Wang
John E. Cronan
Source :
Chemistry & Biology. 20(9):1157-1167
Publication Year :
2013
Publisher :
Elsevier BV, 2013.

Abstract

SummaryIn the classical anaerobic pathway of unsaturated fatty acid biosynthesis, that of Escherichia coli, the double bond is introduced into the growing acyl chain by the FabA dehydratase/isomerase. Another dehydratase, FabZ, functions in the chain elongation cycle. In contrast, Aerococcus viridans has only a single FabA/FabZ homolog we designate FabQ. FabQ can not only replace the function of E. coli FabZ in vivo, but it also catalyzes the isomerization required for unsaturated fatty acid biosynthesis. Most strikingly, FabQ in combination with E. coli FabB imparts the surprising ability to bypass reduction of the trans-2-acyl-ACP intermediates of classical fatty acid synthesis. FabQ allows elongation by progressive isomerization reactions to form the polyunsaturated fatty acid, 3-hydroxy-cis-5, 7-hexadecadienoic acid, both in vitro and in vivo. FabQ therefore provides a potential pathway for bacterial synthesis of polyunsaturated fatty acids.

Details

ISSN :
10745521
Volume :
20
Issue :
9
Database :
OpenAIRE
Journal :
Chemistry & Biology
Accession number :
edsair.doi.dedup.....6512e9b5a9104357b6640d252933c73c
Full Text :
https://doi.org/10.1016/j.chembiol.2013.07.007