期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1979
卷号：76
期号：1
页码：219-222
DOI：10.1073/pnas.76.1.219
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Soluble guanylate cyclase [GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.2 ] has been purified from rat liver and exhibited a single protein band on polyacrylamide gels coincident with activity and indicative of a molecular weight of 150,000. The apparent specific activity of the purified enzyme was 276 nmol of cyclic GMP formed per mg per min with Mn2+ as the cation cofactor and 23.8 nmol of cyclic GMP formed per mg per min with Mg2+. This represented 9200-fold and 7400-fold purifications of Mn2+ and Mg2+ activities, respectively. The specific activity of soluble guanylate cyclase was not constant with protein concentration. At all stages of purification, increasing the enzyme concentration in the guanylate cyclase assay increased the apparent specific activity of the preparation. The purified enzyme could be activated by nitroprusside, nitric oxide, arachidonate, linoleate, oleate, and superoxide dismutase. However, the degree of activation was dependent upon the concentration of enzyme protein assayed.
