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Maria K. Koshkina, Egor
P. Sergeyev, Timofey A. Fedorov, Mèxaèë D. Shelomov, Anastasia A. Pometun, Svyatoslav S. Savin, Vladimir I. Tishkov, Denis L. Atroshenko
Kinetics
of thermoinactivation of D-amino acid oxidase OpaDAAO1 from the Ogataea
parapolymorpha DL-1 yeast
Abstract
Abstract. Our earlier annotation of genome of the yeast Ogataea
parapolymorpha DL-1 made it possible to identify five genes of potential
D-amino acids oxidases. All opadaao1 – opadaao5 genes were cloned and
expressed in E. coli. Four OpaDAAO1- OpaDAAO4 enzymes were obtained in
highly purified form and their catalytic properties were studied. It was found
that among all DAAOs described in the literature so far, the enzyme OpaDAAO1
has the highest catalytic constant kcat with D-Ala, which
makes it promising for practical applications. However, in addition to good
catalytic parameters, effective application of the enzyme in practice requires
high stability and knowledge of the inactivation mechanism, including at
elevated temperatures. In this work we studied the effect of elevated
temperatures on the stability of OpaDAAO1. The enzyme was shown to have high
thermal stability in comparison with majority of other D-amino acid oxidases.
The kinetics of OpaDAAO1 inactivation at different temperatures, initial
concentrations of the enzyme, and in the presence of exogenous FAD were
studied. A possible kinetic scheme of inactivation was proposed
based on the data obtained.
Key words: temperature stability, thermal inactivation kinetics, D-amino acid
oxidase, Ogataea parapolymorpha DL-1
Copyright (C) Chemistry Dept., Moscow State University, 2002
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