2qrk: Difference between revisions

Three structures of saccharopine dehydrogenase (l-lysine-forming) (SDH) have been determined in the presence of sulfate, adenosine monophosphate (AMP), and oxalylglycine (OxGly). In the sulfate-bound structure, a sulfate ion binds in a cleft between the two domains of SDH, occupies one of the substrate carboxylate binding sites, and results in partial closure of the active site of the enzyme due to a domain rotation of almost 12 degrees in comparison to the apoenzyme structure. In the second structure, AMP binds to the active site in an area where the NAD+ cofactor is expected to bind. All of the AMP moieties (adenine ring, ribose, and phosphate) interact with specific residues of the enzyme. In the OxGly-bound structure, carboxylates of OxGly interact with arginine residues representative of the manner in which substrate (alpha-ketoglutarate and saccharopine) may bind. The alpha-keto group of OxGly interacts with Lys77 and His96, which are candidates for acid-base catalysis. Analysis of ligand-enzyme interactions, comparative structural analysis, corroboration with kinetic data, and discussion of a ternary complex model are presented in this study.

Crystal structures of ligand-bound saccharopine dehydrogenase from Saccharomyces cerevisiae., Andi B, Xu H, Cook PF, West AH, Biochemistry. 2007 Nov 6;46(44):12512-21. Epub 2007 Oct 16. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17939687 17939687]

[[Category: Cook, P F.]]

[[Category: West, A H.]]

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