|
type |
Journal Article |
authors |
Liu, J. Q.; Nagata, S.; Dairi, T.; Misono, H.; Shimizu, S.; Yamada, H. |
title |
The GLY1 gene of Saccharomyces cerevisiae encodes a low-specific L- threonine aldolase that catalyzes cleavage of L-allo-threonine and L- threonine to glycine--expression of the gene in Escherichia coli and purification and characterization of the enzyme |
journal |
Eur J Biochem |
Activity |
4.1.2.5 |
Family |
4.1.2.5 |
sel |
selected |
ui |
9151955 |
year |
(1997) |
volume |
245 |
number |
2 |
pages |
289-93 |
| |
keywords |
Aeromonas/enzymology |
abstract |
The GLY1 gene of Saccharomyces cerevisiae is required for the biosynthesis of glycine for cell growth [McNeil, J. B., McIntosh, E. V., Taylor, B. V., Zhang, F-R., Tang, S. & Bognar, A. L. (1994) J. Biol. Chem. 269, 9155-9165], but its gene product has not been identified. We have found that the GLY1 protein is similar in primary structure to L-allo-threonine aldolase of Aeromonas jandiae DK-39, which stereospecifically catalyzes the interconversion of L-allo- threonine and glycine. The GLY1 gene was amplified by PCR, with a designed ribosome-binding site, cloned into pUC118, and expressed in Escherichia coli cells. The enzyme was purified to homogeneity, as judged by polyacrylamide gel electrophoresis. The enzyme has a molecular mass of about 170 kDa and consists of four subunits identical in molecular mass. The enzyme contains 2 mol pyridoxal 5'-phosphate/4 mol of subunit as a cofactor, and its absorption spectrum exhibits maxima at 280 nm and 420 nm. The enzyme catalyzes the cleavage of not only L-allo-threonine to glycine but also L-threonine. We have termed the enzyme a low-specific L-threonine aldolase to distinguish it from L- allo-threonine aldolase. |
last changed |
2009/06/19 13:31 |
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