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