pH-dependent deuterium isotope effects on l-amino-acid oxidase

1969 ◽  
Vol 191 (1) ◽  
pp. 190-192 ◽  
Author(s):  
David S. Page ◽  
Robert L. Vanetten
Keyword(s):  
Amino Acid ◽  
Isotope Effects ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Deuterium Isotope Effects ◽  
Ph Dependent

scholarly journals PH-Dependent Enantioselectivity of D-amino Acid Oxidase in Aqueous Solution

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Qingju Liu ◽  
Li Chen ◽  
Zhikun Zhang ◽  
Bibai Du ◽  
Yating Xiao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Amino Acid ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Ph Dependent

Nitrogen Isotope Effects As Probes of the Mechanism ofd-Amino Acid Oxidase

2000 ◽  
Vol 122 (51) ◽  
pp. 12896-12897 ◽  
Author(s):  
Kevin A. Kurtz ◽  
Mark A. Rishavy ◽  
W. W. Cleland ◽  
Paul F. Fitzpatrick
Keyword(s):  
Amino Acid ◽  
Isotope Effects ◽  
Nitrogen Isotope ◽  
Acid Oxidase ◽  
Amino Acid Oxidase

Methylated derivatives of l-tyrosine in reaction catalyzed by l-amino acid oxidase: isotope and inhibitory effects

2020 ◽  
Vol 168 (5) ◽  
pp. 509-514
Author(s):  
Małgorzata Pająk
Keyword(s):  
Amino Acid ◽  
Bond Cleavage ◽  
Isotope Effects ◽  
Antibacterial Properties ◽  
Competitive Inhibitor ◽  
Inhibitory Effect ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Enzyme Active Site ◽  
Derivatives Of

Abstract l-Amino acid oxidase (LAAO) is widely distributed in nature and shows important biological activity. It induces cell apoptosis and has antibacterial properties. This study was designed to investigate the effect of methyl substituent on its activity as methylated derivatives of l-tyrosine, labelled with short-lived B+ emitters, have been used in oncological diagnostics. To study isotope effects in the oxidative deamination of O-methyl-l-tyrosine, the deuterated isotopomer, i.e. O-methyl-[2-2H]-l-tyrosine, was synthesized by isotope exchange, catalyzed enzymatically by tryptophanase. Isotope effects were determined using the spectrophotometric non-competitive method. The values of isotope effects indicate that the α-C–H bond cleavage occurs in the rate determining step of the investigated reaction and α-hydrogen plays a role in the substrate binding process at the enzyme active site. The inhibitory effect on LAAO activity was studied with α-methyl-l-tyrosine and N-methyl-l-tyrosine. The mode of inhibition was determined based on Lineweavear–Burk plots intersections. α-Methyl-l-tyrosine has been found a mixed type inhibitor of the investigated enzyme, whereas N-methyl-l-tyrosine is a non-competitive inhibitor of LAAO.

Sign in / Sign up

Export Citation Format

Share Document