Isolation and Chemical Properties of Two Calcitonins from Salmon Ultimobranchial Glands

作者：Henry T. Keutmann, JOHN A. PARSONS, John T. Jr. Potts, Robert J. Schlueter · 发表于：Journal of Biological Chemistry · 年份：1970 · DOI：10.1016/s0021-9258(18)63262-4 · 被引用次数：70 · 研究领域：Neuropeptides and Animal Physiology、Adipokines, Inflammation, and Metabolic Diseases、Stress Responses and Cortisol

Calcitonin was extracted from the ultimobranchial gland of salmon in quantities sufficient to permit purification and chemical characterization. The partially purified extract was subjected to gel filtration and ion exchange chromatography. Purification was monitored by bioassay of column effluents against a standard prepared from the starting material. These methods led to detection of two chemically different forms of the hormone. One form, present in higher yield, was shown to be pure by several chemical criteria. This major component of the hormone contained 32 amino acids, but differed markedly in amino acid composition from the previously characterized mammalian calcitonins. The minor component was similar in biological potency to the major peptide but was less basic and showed several other differences in amino acid composition. Both forms of the salmon hormone have the highest specific biological activity of any natural calcitonin thus far described (2,700 MRC units per mg in the rat and 50,000 MRC units per mg in the mouse). These properties of the salmon hormone—high specific biological activity and distinctive chemical features—indicate that it may be useful in the study of structure-function relationships in the calcitonins.