Active factors in crab hatch water -OHSS and a proteinase, and their role on hatching-

潮间带蟹和河口蟹的胚胎聚集在雌蟹的卵生绒毛上，由雌蟹的腹部通风2-4周。当胚胎发育完成时，孵化发生，zoea幼虫被释放到水中。本研究表明，蟹孵化水（即释放动物的过滤介质）中至少含有两种活性物质，即卵生脱毛物质OHSS和一种蛋白水解酶。这两种因素在凝胶过滤下很容易分离。OHSS采用疏水、阴离子交换层析和凝胶过滤三种层析相结合的方法纯化。其分子大小在Superdex 75 （Pharmacia）中为12 K，在SDS-PAGE中为35 K。蛋白酶溶解了卵囊的碎片，这表明这种酶确实对卵囊起作用。但与酪蛋白消化相比，这种活性非常低。这种酶可能会消化包裹胚胎的薄而粘的层，而不会作用于厚而坚韧的层，即卵囊的主要成分。因此，很难设想如此小规模的溶解会导致卵囊的破裂。

Embryos of intertidal and estuarine crabs are clustered on the ovigerous seta of the female, and ventilated 2-4 weeks by the female's abdomen. When the embryonic development is complete, hatching occurs and zoea larvae are released into water. This study indicates that the crab hatch water (i.e., the filtered medium into which zoeas were released) contains at least two kinds of active substance : i.e., OHSS (ovigerous-hair-stripping substance) and a proteolytic enzyme. Both factors were easily separated on gel filtration.OHSS was purified by the combination of three kinds of chromatography : i.e., hydrophobic and anion-exchange chromatographies, and gel filtration. Its molecular size was 12 K in Superdex 75 (Pharmacia), but 35 K in SDS-PAGE.The proteinase dissolved debris of the egg capsule, suggesting that this enzyme actually acts on it. But this activity was at very low level, compared with casein digestion. This enzyme possibly digest a thin, sticky layr enclosing embryos, and would not act on the thick, tough layr, i.e., the main component of the egg capsule. Accordingly, it would be difficult to suppose that such a small scale dissolution causes the breakage of the egg capsule.