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Publication Abstract from PubMed

The structures of 5-aminolaevulinic acid dehydratase complexed with two irreversible inhibitors (4-oxosebacic acid and 4,7-dioxosebacic acid) have been solved at high resolution. Both inhibitors bind by forming a Schiff base link with Lys 263 at the active site. Previous inhibitor binding studies have defined the interactions made by only one of the two substrate moieties (P-side substrate) which bind to the enzyme during catalysis. The structures reported here provide an improved definition of the interactions made by both of the substrate molecules (A- and P-side substrates). The most intriguing result is the novel finding that 4,7-dioxosebacic acid forms a second Schiff base with the enzyme involving Lys 210. It has been known for many years that P-side substrate forms a Schiff base (with Lys 263) but until now there has been no evidence that binding of A-side substrate involves formation of a Schiff base with the enzyme. A catalytic mechanism involving substrate linked to the enzyme through Schiff bases at both the A- and P-sites is proposed.

The X-ray structure of yeast 5-aminolaevulinic acid dehydratase complexed with two diacid inhibitors.,Erskine PT, Coates L, Newbold R, Brindley AA, Stauffer F, Wood SP, Warren MJ, Cooper JB, Shoolingin-Jordan PM, Neier R FEBS Lett. 2001 Aug 17;503(2-3):196-200. PMID:11513881^[1]

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