In Volvox carteri f. nagariensis male spheroids secrete into the medium a sexual hormone which controls the initiation of the developmental pathway leading to the formation of sexual embryos. In the absence of the hormone asexual embryos are formed. Analysis of the highly purified hormone indicates that it is a glycoprotein of 27,500-30,000 daltons, composed of one peptide chain, which has a typical composition except for a relatively low content of tryptophan. The glycosidic moiety, which accounts for about 45% of the weight of the molecule, consists of pentoses, hexoses, and amino hexoses. In the bioassay the highly purified hormone stimulates 100% formation of sexual embryos at a concentration of 10-10 g/liter and 14.4% sexual embryos at 10-11 g/liter (3 × 10-16 M). The activity is remarkably thermostable and resistant to different denaturing procedures.
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机译：在Volvox carteri f。 nagariensis雄性球体将一种性激素分泌到培养基中，该激素控制着导致性胚胎形成的发育途径的启动。在缺乏激素的情况下，会形成无性胚胎。对高度纯化的激素的分析表明，它是一种27,500-30,000道尔顿的糖蛋白，由一条肽链组成，除了色氨酸含量相对较低外，具有典型的组成。糖苷部分约占分子重量的45％，由戊糖，己糖和氨基己糖组成。在生物测定中，高度纯化的激素以10 -10 g /升的浓度刺激100％的性胚胎形成，以10 -11 g /升的浓度刺激14.4％的性胚胎形成。 （3×10 -16 M）。该活性非常热稳定，并能抵抗不同的变性程序。
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