Biomedical subjects

L S Gubnitskiĭ

Publications and source records attributed to L S Gubnitskiĭ.

2 recordsLinked to original sources

PubMed1979

[Dependence of the rate of aspartate ammonia-lyase reaction catalyzed by free and immobilized cells of E. coli on temperature and preliminary thermal treatment].

The effects of temperature (45--55 degrees) and duration of thermal treatment on the L-aspartase activity of free and immobilized on polyacrylamide gel cells of E. coli, strain 85 were studied. It was found that preliminary thermal treatment of the cells at 50 degrees for 40--60 min is optimal for a high aspartase activity. Within the temperature interval of 20--55 degrees the temperature dependence of effective rate constants of L-aspartate synthesis obeys the Arrhenius equation, whereas the effective energy of activation is decreased from 12,6 to 3,6 kcal/mole, when the "activation" of the cells shows an increase.

Ammonia-Lyases↗

PubMedDate not supplied

[L-asparatic acid synthesis from ammonium fumarate by free and immobilized Escherichia coli cells].

E. coli 85 cells with a high aspartate-ammonia-lyase activity were immobilized through polyacrylamide gel incorporation. Proper conditions to assay aspartase activity of E. coli cells were developed. Kinetic patterns of aspartate-ammonia-lyase reaction catalyzed by free and immobilized E. coli 85 cells were studied. The synthesis of L-aspartic acid from ammonium fumarate had the following characteristics: specific activity of (4--6) . 10(-5) mmole/mg.sec for free cells and (6--8) . 10(-5) mmole/mg.sec for immobilized cells with their content in polyacrylamide gel of 5--10 mg protein per g wet gelm pH 8.3--10.0.

Aspartic Acid↗