This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Garbers, D. L. Articles by Kopf, G. S. Search for Related Content PubMed PubMed Citation Articles by Garbers, D. L. Articles by Kopf, G. S.

Purification and characterization of calmodulin from sea urchin spermatozoa

Summary. Calmodulin was purified to apparent homogeneity from sea urchin spermatozoa by heat-treatment at 85°C, ammonium sulphate precipitation at pH 4·2, DEAE-Sephacel chromatography and gel filtration on Sephadex G-100. Approximately 8·3 µg calmodulin were recovered per 10¹⁰ sperm cells. The sperm calmodulin had an apparent molecular weight of 17 800. The purified calmodulin activated calmodulin-deficient phosphodiesterase from pig coronary arteries, with half-maximal activation occurring at approximately 40 ng calmodulin/ml. Trifluoperazine also inhibited the sperm calmodulin activity. These results demonstrate that calmodulin is present in high amounts in sea urchin spermatozoa, and that it is essentially the same as the calmodulin isolated from various other tissues.