|
type |
Journal Article |
authors |
Takechi M, Kanda M, Hori K, Kurotsu T, Saito Y.
|
title |
Purification and properties of L-ornithine delta-aminotransferase from gramicidin S-producing Bacillus brevis |
journal |
J Biochem |
Activity |
2.6.1.13 |
Family |
2.6.1.13.a |
sel |
selected |
ui |
7534759 |
year |
(1994) |
volume |
116 |
number |
5 |
pages |
955-9 |
| |
abstract |
In gramicidin S-producing Bacillus brevis, the addition of L-ornithine to the minimal medium with L-glutamate as the sole carbon and nitrogen source caused an 8-fold induction of L-ornithine delta-aminotransferase [EC 2.6.1.13]. The enzyme was purified to homogeneity. The native enzyme had a molecular weight of about 88,000 after gel filtration and consisted of two subunits with an identical in molecular weight of about 45,000. The enzyme was specific for L-ornithine (Km = 1.05 mM) as an amino donor and for 2-oxoglutarate (Km = 6.25 mM) as an amino acceptor, and catalyzed the conversion of L-ornithine and 2-oxoglutarate, respectively, to glutamic-gamma-semialdehyde, which is spontaneously cyclized to delta 1-pyrroline-5-carboxylate and L-glutamate. The enzyme exhibits an absorption maximum at 425 nm at neutral pH, and 1 mol of pyridoxal phosphate is bound per subunit. The enzyme activity was irreversibly inhibited by gabaculine, and L-ornithine protected the enzyme from the inhibition. The N-terminal amino acid sequence revealed a noteworthy similarity between human and yeast L-ornithine delta-aminotransferases in residues 17-28 of the B. brevis enzyme. |
last changed |
2018/01/23 11:10 |
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