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2o7b
From Proteopedia
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Tyrosine ammonia-lyase from Rhodobacter sphaeroides, complexed with coumarate
Overview
Aromatic amino acid ammonia-lyases catalyze the deamination of L-His, L-Phe, and L-Tyr, yielding ammonia plus aryl acids bearing an, alpha,beta-unsaturated propenoic acid. We report crystallographic analyses, of unliganded Rhodobacter sphaeroides tyrosine ammonia-lyase (RsTAL) and, RsTAL bound to p-coumarate and caffeate. His 89 of RsTAL forms a hydrogen, bond with the p-hydroxyl moieties of coumarate and caffeate. His 89 is, conserved in TALs but replaced in phenylalanine ammonia-lyases (PALs) and, histidine ammonia-lyases (HALs). Substitution of His 89 by Phe, a, characteristic residue of PALs, yields a mutant with a switch in kinetic, preference from L-Tyr to L-Phe. Structures of the H89F mutant in complex, with the PAL product, cinnamate, or the PAL-specific inhibitor, 2-aminoindan-2-phosphonate (AIP), support the role of position 89 as a, specificity determinant in the family of aromatic amino acid, ammonia-lyases and aminomutases responsible for beta-amino acid, biosynthesis.
About this Structure
2O7B is a Single protein structure of sequence from Rhodobacter sphaeroides with as ligand. Full crystallographic information is available from OCA.
Reference
Structural determinants and modulation of substrate specificity in phenylalanine-tyrosine ammonia-lyases., Louie GV, Bowman ME, Moffitt MC, Baiga TJ, Moore BS, Noel JP, Chem Biol. 2006 Dec;13(12):1327-38. PMID:17185228
Page seeded by OCA on Tue Jan 29 21:06:17 2008
