Article

Functional and structural properties of mammalian acyl-coenzyme A thioesterases.

School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia.
Progress in lipid research (impact factor: 10.67). 10/2010; 49(4):366-77. DOI:10.1016/j.plipres.2010.04.001 pp.366-77
Source: PubMed

ABSTRACT Acyl-coenzyme A thioesterases (Acots) play important cellular roles in mammalian fatty acid metabolism through modulation of cellular concentrations of activated fatty acyl-CoAs. Acots catalyse the hydrolysis of the thioester bond present within acyl-CoA ester molecules to yield coenzyme A (CoASH) and the corresponding non-esterified fatty acid. Acyl-CoA thioesterases are expressed ubiquitously in both prokaryotes and eukaryotes and, in higher order organisms, the enzymes are expressed and localised in a tissue-dependent manner within the cytosol, mitochondria, peroxisomes and endoplasmic reticulum. Recent studies have led to advances in the functional and structural characterization of many mammalian Acot family members. These include the structure determination of both type-I and type-II Acot family members, structural elucidation of the START domain of ACOT11, identification of roles in arachidonic acid and inflammatory prostaglandin production by Acot7, and inclusion of a 13th Acot family member. Here, we review and analyse the current literature on mammalian Acots with respect to their characterization and summarize the current knowledge on the structure, function and regulation of this enzyme family.

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Keywords

13th Acot family member
 
Acots
 
acyl-CoA ester molecules
 
Acyl-CoA thioesterases
 
arachidonic acid
 
corresponding non-esterified fatty acid
 
enzyme family
 
inflammatory prostaglandin production
 
mammalian Acot family members
 
mammalian Acots
 
mammalian fatty acid metabolism
 
Recent studies
 
START domain
 
structural characterization
 
structural elucidation
 
structure determination
 
thioester bond present
 
thioesterases
 
type-II Acot family members
 
yield coenzyme