|
type |
Journal Article |
authors |
Ishikawa, T.; Okuno, E.; Kawai, J.; Kido, R. |
title |
Organ distribution, purification and characterization of kynureninase in Suncus murinus (Insectivora) and anthranilic acid level in the serum |
journal |
Comp Biochem Physiol B |
Activity |
3.7.1.3 |
ui |
89324647 |
year |
(1989) |
volume |
93 |
number |
1 |
pages |
107-11 |
| |
keywords |
Animal |
abstract |
1. The highest kynureninase activity was measured in Suncus liver compared with other organs tested. The holo-enzyme activity detected in liver was 25%. 2. The enzyme mainly localized in liver cytosol was purified to a single protein band by heat treatment, ammonium sulfate fractionation, DEAE-sepharose, hydroxyapatite and phenyl-sepharose column chromatography. 3. The purified enzyme was effective for both kynurenine and 3-hydroxykynurenine, and showed the optimum pH at 8.5 against both substrates. 4. Km values were 250 microM, 18 microM and 70 microM for kynurenine, 3-hydroxykynurenine and pyridoxal 5'-phosphate, respectively. Various compounds such as histidine, aspartate and nicotinamide enhanced the enzyme activities. 5. Anthranilate, the product of kynureninase, was present at a concentration in Suncus serum of 1.96 microM. This value was higher than those of rat and human. |
last changed |
2002/11/12 16:17 |
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