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Publication Abstract from PubMed

Clostridium propionicum is the only organism known to ferment beta-alanine, a constituent of coenzyme A (CoA) and the phosphopantetheinyl prosthetic group of holo-acyl carrier protein. The first step in the fermentation is a CoA-transfer to beta-alanine. Subsequently, the resulting beta-alanyl-CoA is deaminated by the enzyme beta-alanyl-CoA:ammonia lyase (Acl) to reversibly form ammonia and acrylyl-CoA. We have determined the crystal structure of Acl in its apo-form at a resolution of 0.97 A as well as in complex with CoA at a resolution of 1.59 A. The structures reveal that the enyzme belongs to a superfamily of proteins exhibiting a so called "hot dog fold" which is characterized by a five-stranded antiparallel beta-sheet with a long alpha-helix packed against it. The functional unit of all "hot dog fold" proteins is a homodimer containing two equivalent substrate binding sites which are established by the dimer interface. In the case of Acl, three functional dimers combine to a homohexamer strongly resembling the homohexamer formed by YciA-like acyl-CoA thioesterases. Here, we propose an enzymatic mechanism based on the crystal structure of the Acl.CoA complex and molecular docking. Proteins 2014. (c) 2014 Wiley Periodicals, Inc.

High resolution crystal structure of Clostridium propionicum beta-alanyl-CoA:ammonia lyase, a new member of the "hot dog fold" protein superfamily.,Heine A, Herrmann G, Selmer T, Terwesten F, Buckel W, Reuter K Proteins. 2014 Mar 13. doi: 10.1002/prot.24557. PMID:24623648^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.