title: Solubilization and resolution of thromboxane synthesizing system from microsomes of bovine blood platelets.
abstract: The thromboxane synthetase system of the microsomes of bovine blood platelets was solubilized by the treatment with Triton X-100. The solubilized preparation was separated into two enzyme fractions by DEAE-cellulose chromatography. One catalyzed the formation of prostaglandin H2 from arachidonic acid in the presence of heme and tryptophan. The other fraction converted prostaglandin H2 to thromboxane B2 and 12L-hydroxy-5,8,10-heptadecatrienoic acid. However, incubation of the latter fraction with prostaglandin H2 at lower temperature produced an unstable compound with platelet-aggregating activity, which was presumably thromboxane A2 and which decomposed readily to thromboxane B2 and 12L-hydroxy-5,8,10-heptadecatrienoic acid.
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000097:blood; D001792:Blood Platelets / Q000378:metabolism*; D002417:Cattle; D006880:Hydroxy Acids / Q000096:biosynthesis; D008861:Microsomes / Q000378:metabolism*; D010088:Oxidoreductases / Q000097:blood / Q000302:isolation & purification; D010974:Platelet Aggregation; D011092:Polyethylene Glycols; D011453:Prostaglandins / Q000097:blood; D011714:Pyrans / Q000096:biosynthesis; D012995:Solubility
chemical_list: D001095:Arachidonic Acids; D006880:Hydroxy Acids; D011453:Prostaglandins; D011714:Pyrans; D011092:Polyethylene Glycols; D010088:Oxidoreductases