4je5

Publication Abstract from PubMed

alpha-Aminoadipate aminotransferase (AAA-AT) catalyzes the amination of 2-oxoadipate to alpha-aminoadipate in the fourth step of the alpha-aminoadipate pathway of lysine biosynthesis in fungi. The aromatic aminotransferase Aro8 has recently been identified as an AAA-AT in Saccharomyces cerevisiae. This enzyme displays broad substrate selectivity, utilizing several amino acids and 2-oxo acids as substrates. Here we report the 1.91A resolution crystal structure of Aro8 and compare it to AAA-AT LysN from Thermus thermophilus and human kynurenine aminotransferase II. Inspection of the active site of Aro8 reveals asymmetric cofactor binding with lysine-pyridoxal-5-phosphate bound within the active site of one subunit in the Aro8 homodimer and pyridoxamine phosphate and a HEPES molecule bound to the other subunit. The HEPES buffer molecule binds within the substrate-binding site of Aro8, yielding insights into the mechanism by which it recognizes multiple substrates and how this recognition differs from other AAA-AT/kynurenine aminotransferases.

Crystal structure of Saccharomyces cerevisiae Aro8, a putative alpha-aminoadipate aminotransferase.,Bulfer SL, Brunzelle JS, Trievel RC Protein Sci. 2013 Jul 24. doi: 10.1002/pro.2315. PMID:23893908^[1]

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