Purification and Characterization of Bovine Follicle-Stimulating Hormone: Comparison with Ovine Follicle-Stimulating Hormone*

Abstract

Highly purified FSH was obtained from several batches of bovine pituitaries by sequential application of the following procedures: 1) extraction with an alcoholic sodium acetate buffer, 2) fractionation with metaphosphoric acid, 3) fractionation with ammonium sulfate, 4) gel filtration on Sephadex G-150, 5) ion exchange chromatography on CM-Sephadex, 6) chromatography on hydroxylapatite, 7) gel filtration on Sephadex G-100, and 8) preparative acrylamide disc gel electrophoresis, followed by another gel filtration on Sephadex G-100. pproximately 1.3 mg FSH, containing activity equivalent to 47 U NIH-FSH-Sl/mg, were obtained from 1 kg glands. This FSH contained less than 0.01 U NIH-LH-Sl/mg, as determined by the ovarian ascorbic acid depletion assay. The subunits of bovine FSH (bFSH) were isolated by treatment of the hormone with 8 M urea, followed by ion exchange chromatography on DEAESephadex and gel filtration on Sephadex G-100. bFSH was similar to its ovine counterpart with regard to its electrophoretic properties, molecular weight, and amino acid content. The apparent molecular weights of bFSH and its a- and ∧-subunits were 37,300, 12,600, and 18,500, respectively. bFSH contained high amounts of aspartic acid, threonine, glutamic acid, half-cystine, and lysine, but only low amounts of methionine, histidine, and tryptophan. bFSH differed from its obvine counterpart with regard to its carbohydrate content and biological properties. Although bFSH contained the same sugars as ovine FSH, it possessed twice as much galactosamine, but only 66% of the sialic acid. bFSH was only one third as potent biologically in the augmentation bioassay as the ovine hormone.