|
type |
Journal Article |
authors |
Chang, C. C.; Laghai, A.; O'Leary, M. H.; Floss, H. G. |
title |
Some stereochemical features of aspartate beta-decarboxylase |
journal |
J Biol Chem |
Activity |
4.1.1.12 |
ui |
82142522 |
year |
(1982) |
volume |
257 |
number |
7 |
pages |
3564-9. |
| |
keywords |
Alcaligenes/enzymology |
abstract |
Aspartate beta-decarboxylase catalyzes abortive decarboxylation/transamination of [2-3H]aspartate with at least 17% internal transfer of tritium to the pro-S position at C-4' of the resulting pyridoxamine phosphate. In the normal beta-decarboxylation reaction, at least 1.06% of the tritium from the alpha-position of aspartate appears in the product alanine. The enzyme catalyzes slow hydrogen exchange from the beta-position of alanine but not aspartate. The replacement of the beta-carboxyl group of aspartate by hydrogen occurs in an inversion mode. These results are interpreted in terms of a two-base mechanism. |
last changed |
2002/11/12 16:17 |
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