Isolation of intact transition protein 1 and 3 from boar late spermatid nuclei

Boar transition protein 1 and 3 were extracted with acid from the late spermatid nuclei, separated from the TP-degrading proteases by ion-exchange chromatography on Fractogel EMD SO3- 650 (M), and further purified by HPLCs on Diol-120 and on Hitachi #3057, respectively. The circular dichroic spectra of the transition proteins with and without dithiothreitol showed that they have beta-form predominantly. Although sodium dodecyl sulfate partially induced helical structure, the beta-form was considerably retained. These indicate that the transition proteins have a structure-forming potential for the beta-structure.