The activity and reaction specificity of tyrosine phenol-lyase regulated by monovalent cations |
| |
Authors: | T V Demidkina I V Myagkikh |
| |
Affiliation: | Engelhardt Institute of Molecular Biology, USSR Academy of Sciences, Moscow. |
| |
Abstract: | This work was aimed at studying the effect of monovalent inorganic cations (Li+, Na+, K+, Rb+, Cs+, NH+4) on the catalytic and spectral characteristics of tyrosine phenol-lyase from Citrobacter intermedius. These cations were shown to influence the proportion of the beta-elimination reaction rate to the rate of side transamination reaction. Most of the monovalent cations are non-competitive activators of the beta-elimination reaction; Li+ exerts no effect on the enzyme activity in this reaction; Na+ is an inhibitor of the beta-elimination reaction. The activation of tyrosine phenol-lyase by monovalent cations stems from the creation of an active holoenzyme form (lambda max 420 nm) due to conformational rearrangements of the protein molecule. |
| |
Keywords: | |
|
|