5m3z

Publication Abstract from PubMed

The mutant form of Citrobacter freundii methionine gamma-lyase with the replacement of active site Cys115 for His has been found to be inactive in the gamma-elimination reaction of methionine while fully active in the gamma-elimination reaction of O-acetyl-l-homoserine and in the beta-elimination reaction of S-alk(en)yl-substituted cysteines. In this work, the crystal structure of the mutant enzyme complexed with competitive inhibitor, l-norleucine was determined at 1.45A resolution. At the enzyme active site the inhibitor proved to be bound both noncovalently and covalently, which corresponds to the two intermediates of the gamma- and beta-elimination reactions, Michaelis complex and the external aldimine. Analysis of the structure allowed us to suggest the possible reason for the inability of the mutant enzyme to catalyze the physiological reaction.

Crystal structure of mutant form Cys115His of Citrobacter freundii methionine gamma-lyase complexed with l-norleucine.,Revtovich SV, Morozova EA, Kulikova VV, Anufrieva NV, Osipova TI, Koval VS, Nikulin AD, Demidkina TV Biochim Biophys Acta. 2017 Sep;1865(9):1123-1128. doi:, 10.1016/j.bbapap.2017.06.001. Epub 2017 Jun 6. PMID:28602917^[1]

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