期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1984
卷号：30
期号：5
页码：405-413
DOI：10.3177/jnsv.30.405
出版社：Center for Academic Publications Japan
摘要：A simple spectrophotometric method for assay of ATP: cob(I)alamin Co-β-adenosyltransferase was established. By using this method, specific activity of the enzyme in Protaminobacter ruber was found to be the highest in the logarithmic growth phase. The enzyme was highly purified from the cells in that phase and characterized. The molecular weight of the enzyme was estimated as 44, 000 by gel filtration. The optimal pH and temperature were about 8.0 and 50°C, respectively. Among divalent metal ions tested, only Mg2+ was effective for the enzyme activity. K m values for ATP and hydroxocobalamin were 250 μM and 26.3 μM, respectively. Substrate analogs such as GTP and CTP had only small activity in the enzymatic reaction.
