Role of Tyrosine 114 of L-Methionine γ-lyase from Pseudomonas putida

50Citations
Citations of this article
19Readers
Mendeley users who have this article in their library.
Get full text

Abstract

L-Methionine γ-lyase from Pseudomonas putida has a conserved tyrosine residue (Tyr114) in the active site as in all known sequences of γ-family pyridoxal 5′-phosphate dependent enzymes. A mutant form of L-methionine γ-lyase in which Tyr114 was replaced by phenylalanine (Y114F) resulted in 910-fold decrease in kcat for α,γ-elimination of L-methionine, while the Km remained the same as the wild type enzyme. The Y114F mutant had the reduced kcat by only 28- and 16-fold for substrates with an electron-withdrawing group at the γ-position, namely O-acetyl-L-homoserine and L-methionine sulfone, respectively, and also the similar reduction of kcat for α,β-elimination and deamination substrates. The hydrogen exchange reactions of substrate and the spectral changes of the substrate-enzyme complex catalyzed by the mutant enzyme suggested that γ-elimination process for L-methionine is the rate-limiting determination step in α,γ-elimination overall reaction of the Y114F mutant. These results indicate that Tyr114 of L-methionine γ-lyase is important in γ-elimination of the substrate. © 2000, Taylor & Francis Group, LLC. All rights reserved.

Cite

CITATION STYLE

APA

Inoue, H., Inagaki, K., Adachi, N., Tamura, T., Esaki, N., Soda, K., & Tanaka, H. (2000). Role of Tyrosine 114 of L-Methionine γ-lyase from Pseudomonas putida. Bioscience, Biotechnology and Biochemistry, 64(11), 2336–2343. https://doi.org/10.1271/bbb.64.2336

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free