Abstract
Adenosine-5′-phosphosulfate kinase (ATP: adenylylsulfate-3′-phosphotransferase, EC 2.7.1.25) was purified from the thalli of the marine alga Porphyra yezoensis by means of salt fractionation, affinity, gel filtration, and ion exchange chromatography. The native enzyme had a Mr of about 61000. Dissociation yielded a form of Mr about 31000. The maximum enzyme activity was at pH 7.0, and requires a divalent metal ion. Triphosphates of adenosine, cytidine, guanine, inosine, and uridine were active as the phosphate donor substrate. Adenosine-5′-phosphosulfate exhibited potent substrate inhibition; the optimal concentration was 3.0 μM in the presence of excess ATP and Mg2+. Michaelis constants for APS and ATP were 0.45 μM and 0.46 mM, respectively.
Original language | English |
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Pages (from-to) | 369-374 |
Number of pages | 6 |
Journal | Botanica Marina |
Volume | 33 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1990 Jan 1 |
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science
- Plant Science