2Q2B

Crystal structure of the C-terminal domain of mouse acyl-CoA thioesterase 7

Summary for 2Q2B

• Entry DOI: 10.2210/pdb2q2b/pdb
• Descriptor: Cytosolic acyl coenzyme A thioester hydrolase (2 entities in total)
• Functional Keywords: acot7, c-terminal domain, hydrolase
• Biological source: Mus musculus (house mouse)
• Cellular location: Isoform A: Cytoplasm. Isoform D: Cytoplasm: Q91V12
• Total number of polymer chains: 2
• Total formula weight: 39913.57

Authors

Guncar, G.,Forwood, J.K.,Kobe, B. (deposition date: 2007-05-27, release date: 2007-07-17, Last modification date: 2023-08-30)

Primary citation

Forwood, J.K.,Thakur, A.S.,Guncar, G.,Marfori, M.,Mouradov, D.,Meng, W.,Robinson, J.,Huber, T.,Kellie, S.,Martin, J.L.,Hume, D.A.,Kobe, B.
Structural basis for recruitment of tandem hotdog domains in acyl-CoA thioesterase 7 and its role in inflammation.
Proc.Natl.Acad.Sci.Usa, 104:10382-10387, 2007

PubMed Abstract: Acyl-CoA thioesterases (Acots) catalyze the hydrolysis of fatty acyl-CoA to free fatty acid and CoA and thereby regulate lipid metabolism and cellular signaling. We present a comprehensive structural and functional characterization of mouse acyl-CoA thioesterase 7 (Acot7). Whereas prokaryotic homologues possess a single thioesterase domain, mammalian Acot7 contains a pair of domains in tandem. We determined the crystal structures of both the N- and C-terminal domains of the mouse enzyme, and inferred the structure of the full-length enzyme using a combination of chemical cross-linking, mass spectrometry, and molecular modeling. The quaternary arrangement in Acot7 features a trimer of hotdog fold dimers. Both domains of Acot7 are required for activity, but only one of two possible active sites in the dimer is functional. Asn-24 and Asp-213 (from N- and C-domains, respectively) were identified as the catalytic residues through site-directed mutagenesis. An enzyme with higher activity than wild-type Acot7 was obtained by mutating the residues in the nonfunctional active site. Recombinant Acot7 was shown to have the highest activity toward arachidonoyl-CoA, suggesting a function in eicosanoid metabolism. In line with the proposal, Acot7 was shown to be highly expressed in macrophages and up-regulated by lipopolysaccharide. Overexpression of Acot7 in a macrophage cell line modified the production of prostaglandins D2 and E2. Together, the results link the molecular and cellular functions of Acot7 and identify the enzyme as a candidate drug target in inflammatory disease.

PubMed: 17563367
DOI: 10.1073/pnas.0700974104

Experimental method

X-RAY DIFFRACTION (2.5 Å)