Abstract
Alanine:glyoxylate aminotransferase (EC 2.6.1.44), which is involved in the glyoxylate pathway of glycine and serine biosynthesis from tricarboxylic acid-cycle intermediates in Saccharomyces cerevisiae, was highly purified and characterized. The enzyme had M(r) about 80,000, with two identical subunits. It was highly specific for L-alanine and glyoxylate and contained pyridoxal 5'-phosphate as cofactor. The apparent K(m) values were 2.1mM and 0.7 mM for L-alanine and glyoxylate respectively. The activity was low (10 nmol/min per mg of protein) with glucose as sole carbon source, but was remarkably high with ethanol or acetate as carbon source (930 and 430 nmol/min per mg respectively). The transamination of glyoxylate is mainly catalysed by this enzyme in ethanol-grown cells. When glucose-grown cells were incubated in medium containing ethanol as sole carbon source, the activity markedly increased, and the increase was completely blocked by cycloheximide, suggesting that the enzyme is synthesized de novo during the incubation period. Similarity in the amino acid composition was observed, but immunological cross-reactivity was not observed among alanine:glyoxylate aminotransferases from yeast and vertebrate liver.
| Original language | English |
|---|---|
| Pages (from-to) | 157-163 |
| Number of pages | 7 |
| Journal | Biochemical Journal |
| Volume | 231 |
| Issue number | 1 |
| Publication status | Published - 1985 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Biochemistry
Cite this
Characteristics of alanine : glyoxylate aminotransferase from Saccharomyces cerevisiae, a regulatory enzyme in the glyoxylate pathway of glycine and serine biosynthesis from tricarboxylic acid-cycle intermediates. / Takada, Y.; Noguchi, T.
In: Biochemical Journal, Vol. 231, No. 1, 1985, p. 157-163.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Characteristics of alanine
T2 - glyoxylate aminotransferase from Saccharomyces cerevisiae, a regulatory enzyme in the glyoxylate pathway of glycine and serine biosynthesis from tricarboxylic acid-cycle intermediates
AU - Takada, Y.
AU - Noguchi, T.
PY - 1985
Y1 - 1985
N2 - Alanine:glyoxylate aminotransferase (EC 2.6.1.44), which is involved in the glyoxylate pathway of glycine and serine biosynthesis from tricarboxylic acid-cycle intermediates in Saccharomyces cerevisiae, was highly purified and characterized. The enzyme had M(r) about 80,000, with two identical subunits. It was highly specific for L-alanine and glyoxylate and contained pyridoxal 5'-phosphate as cofactor. The apparent K(m) values were 2.1mM and 0.7 mM for L-alanine and glyoxylate respectively. The activity was low (10 nmol/min per mg of protein) with glucose as sole carbon source, but was remarkably high with ethanol or acetate as carbon source (930 and 430 nmol/min per mg respectively). The transamination of glyoxylate is mainly catalysed by this enzyme in ethanol-grown cells. When glucose-grown cells were incubated in medium containing ethanol as sole carbon source, the activity markedly increased, and the increase was completely blocked by cycloheximide, suggesting that the enzyme is synthesized de novo during the incubation period. Similarity in the amino acid composition was observed, but immunological cross-reactivity was not observed among alanine:glyoxylate aminotransferases from yeast and vertebrate liver.
AB - Alanine:glyoxylate aminotransferase (EC 2.6.1.44), which is involved in the glyoxylate pathway of glycine and serine biosynthesis from tricarboxylic acid-cycle intermediates in Saccharomyces cerevisiae, was highly purified and characterized. The enzyme had M(r) about 80,000, with two identical subunits. It was highly specific for L-alanine and glyoxylate and contained pyridoxal 5'-phosphate as cofactor. The apparent K(m) values were 2.1mM and 0.7 mM for L-alanine and glyoxylate respectively. The activity was low (10 nmol/min per mg of protein) with glucose as sole carbon source, but was remarkably high with ethanol or acetate as carbon source (930 and 430 nmol/min per mg respectively). The transamination of glyoxylate is mainly catalysed by this enzyme in ethanol-grown cells. When glucose-grown cells were incubated in medium containing ethanol as sole carbon source, the activity markedly increased, and the increase was completely blocked by cycloheximide, suggesting that the enzyme is synthesized de novo during the incubation period. Similarity in the amino acid composition was observed, but immunological cross-reactivity was not observed among alanine:glyoxylate aminotransferases from yeast and vertebrate liver.
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M3 - Article
VL - 231
SP - 157
EP - 163
JO - Biochemical Journal
JF - Biochemical Journal
SN - 0264-6021
IS - 1
ER -