Abstract
The microsomal fraction of bovine vesicular gland catalyzed the conversion of [1-14C]8,11,14-eicosatrienoic acid to prostaglandin E1 in the presence of tryptophan, hemoglobin, and glutathione. The prostaglandin synthetase system was solubilized by treatment of the microsomal fraction with Tween 20 in the presence of ethylene glycol. DEAE-cellulose column chromatography separated the enzyme into two fractions (Fractions I and II), both of which were required for prostaglandin E1 synthesis. When Fraction I alone was incubated with 8,11,14-eicosatrienoic acid, an unstable compound accumulated. This compound was converted to prostaglandin E1 by the addition of Fraction II. On the basis of its RF values on thin-layer chromatography, its reduction to prostaglandin F1α with stannous chloride, and the decomposition to prostaglandins F1α, E1, and D1 at room temperature, the unstable intermediate was tentatively identified to be the 9,11-endoperoxide derivative, referred to previously as prostaglandin R1 (Nugteren et al. (1973) Biochim. Biophys. Acta 326, 448-461) or prostaglandin H1 (Hamberg et al. (1974) Proc. Nat. Acad. Sci. USA 71, 345-349). Of the three cofactors mentioned above, Fraction I required both tryptophan and hemoglobin, while only glutathione was necessary for Fraction II. Anti-inflammatory agents such as indomethacin and aspirin were inhibitory to Fraction I.
Keywords: unsaturated fatty acid, endoperoxide, glutathione, hemoglobin, indomethacin
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Selected References
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- Hamberg M., Samuelsson B. Detection and isolation of an endoperoxide intermediate in prostaglandin biosynthesis. Proc Natl Acad Sci U S A. 1973 Mar;70(3):899–903. doi: 10.1073/pnas.70.3.899. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hamberg M., Samuelsson B. On the mechanism of the biosynthesis of prostaglandins E-1 and F-1-alpha. J Biol Chem. 1967 Nov 25;242(22):5336–5343. [PubMed] [Google Scholar]
- Hamberg M., Svensson J., Wakabayashi T., Samuelsson B. Isolation and structure of two prostaglandin endoperoxides that cause platelet aggregation. Proc Natl Acad Sci U S A. 1974 Feb;71(2):345–349. doi: 10.1073/pnas.71.2.345. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Lands W., Lee R., Smith W. Factors regulating the biosynthesis of various prostaglandins. Ann N Y Acad Sci. 1971 Apr 30;180:107–122. doi: 10.1111/j.1749-6632.1971.tb53190.x. [DOI] [PubMed] [Google Scholar]
- Nugteren D. H., Hazelhof E. Isolation and properties of intermediates in prostaglandin biosynthesis. Biochim Biophys Acta. 1973 Dec 20;326(3):448–461. doi: 10.1016/0005-2760(73)90145-8. [DOI] [PubMed] [Google Scholar]
- SAMUELSSON B. ON THE INCORPORATION OF OXYGEN IN THE CONVERSION OF 8, 11, 14-EICOSATRIENOIC ACID TO PROSTAGLANDIN E1. J Am Chem Soc. 1965 Jul 5;87:3011–3013. doi: 10.1021/ja01091a043. [DOI] [PubMed] [Google Scholar]
- Takeguchi C., Kono E., Sih C. J. Mechanism of prostaglandin biosynthesis. I. Characterization and assay of bovine prostaglandin synthetase. Biochemistry. 1971 Jun 8;10(12):2372–2376. doi: 10.1021/bi00788a030. [DOI] [PubMed] [Google Scholar]
- Yoshimoto A., Ito H., Tomita K. Cofactor requirements of the enzyme synthesizing prostagland in bovine seminal vesicles. J Biochem. 1970 Oct;68(4):487–499. doi: 10.1093/oxfordjournals.jbchem.a129379. [DOI] [PubMed] [Google Scholar]
