|
type |
Journal Article |
authors |
Ueno, S.; Morino, H.; Sano, A.; Kakimoto, Y. |
title |
Purification and characterization of D-3-aminoisobutyrate-pyruvate aminotransferase from rat liver |
journal |
Biochim Biophys Acta |
Activity |
2.6.1.40 |
ui |
90167095 |
year |
(1990) |
volume |
1033 |
number |
2 |
pages |
169-75. |
| |
keywords |
Animal |
abstract |
D-3-Aminoisobutyrate-pyruvate aminotransferase (EC 2.6.1.40) was purified 1900-fold from rat liver extract. The purified enzyme showed a molecular mass of 180 kDa by gel-permeation HPLC analysis using a TSK gel G3000SW column. Reductive polyacrylamide gel electrophoresis in sodium dodecyl sulfate resulted in identification of a single band of approx. 50 kDa, indicating that the native enzyme is probably a tetrametric protein. The specific activity of the purified enzyme was 1.14 mumol/min per mg protein. D-3-Aminoisobutyrate and beta-alanine were good amino donors. The Km value for L-3-aminoisobutyrate was 100- times larger than that for the D-isomer. The apparent Km values for D-3- aminoisobutyrate and beta-alanine were 35 and 282 microM, respectively. Pyruvate, glyoxylate, oxalacetate, 2-oxo-n-valerate, and 2-oxo-n- butyrate were good amino acceptors. The apparent Km values for pyruvate and glyoxylate were 32 and 44 microM, respectively. |
last changed |
2002/11/12 16:17 |
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