Aspartate aminotransferase complexed with erythro-beta-hydroxyaspartate: crystallographic and spectroscopic identification of the carbinolamine intermediate

Biochemistry
A G von Stosch

Abstract

The crystal structure of mitochondrial aspartate aminotransferase (mAAT) of chicken complexed with erythro-beta-hydroxyaspartate has been determined at 2.4 A resolution. Pregrown crystals of mAAT complexed with the inhibitor maleate (closed enzyme conformation, orthorhombic space group C222(1)) were soaked in solutions of erythro-beta-hydroxyaspartate. The ligand exchange was monitored by microspectrophotometry. The active site turned out to be predominantly occupied by the carbinolamine intermediate. The carbinolamine is a true intermediate of the catalytic cycle forming the last covalently bound enzyme:substrate complex before release of the keto acid product. Occupancies of approximately 80% for the carbinolamine and of approximately 20% for the quinonoid intermediate were obtained. Two hydrogen bonds were identified that are potentially relevant for the accumulation of the carbinolamine intermediate: one to the hydroxyl group of Tyr 70* and the other to the epsilon-NH2 group of Lys 258.

References

May 20, 1992·Journal of Molecular Biology·C A McPhalenJ N Jansonius
Sep 5, 1991·Journal of Molecular Biology·V N Malashkevich, N I Sinitzina
Jan 1, 1990·Annals of the New York Academy of Sciences·J E TaylorA Arnone
Apr 15, 1984·Journal of Molecular Biology·J F KirschP Christen
Jan 1, 1984·Progress in Biophysics and Molecular Biology·E N Baker, R E Hubbard

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Citations

Oct 15, 2013·Archives of Biochemistry and Biophysics·Michael D Toney
Aug 1, 2014·Molecules : a Journal of Synthetic Chemistry and Natural Product Chemistry·Anna KwiecieńZbigniew Ciunik
Apr 2, 2013·Enzyme and Microbial Technology·Martin Bommer, John M Ward
Sep 26, 2002·Journal of Biochemistry and Molecular Biology·Hyeon-Su Ro

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