|
type |
Journal Article |
authors |
el-Rahmany, T. A. |
title |
Comparison of L-aspartate 4-carboxy-lyases of Cunninghamella elegans and Penicillium citrinum |
journal |
Microbiol Res |
Activity |
4.1.1.12 |
ui |
95079173 |
year |
(1994) |
volume |
149 |
number |
3 |
pages |
253-7. |
| |
keywords |
Alanine/biosynthesis |
abstract |
L-Aspartate 4-carboxy-lyase of Cunninghamella elegans and Penicillium citrinum has a pH optimum of 5.5. Maximal activity of both enzymes is obtained at 40 degrees C, and both are thermolabile. The Km of the C. elegans enzyme for L-aspartate is 25 mM, while that of the P. citrinum enzyme is 27 mM. The two enzymes are specific for L-aspartate. They are activated by pyridoxal 5-phosphate and a number of alpha-keto acids. The catalytic activity of both enzymes is stimulated by Co2+, Fe2+, Ni2+ and Mn2+ ions and inhibited by Zn2+ and Cu2+. Inhibition by iodoacetate and activation by SH-compounds suggest that sulfhydryl groups may participate in enzyme activity. |
last changed |
2002/11/12 16:17 |
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