Yurewixz E C, Oliphant G, Hedrick J L
Biochemistry. 1975 Jul 15;14(14):3101-7. doi: 10.1021/bi00685a010.
The three morphologically and functionally distinct jelly coat layers of Xenopus laevis eggs, J1, J2, and J3, were separated by manual dissection, solubilized with dithiothreitol, and physicochemically analyzed. The chemical composition of the three jelly layers varied from 37 to 48% protein and 63 to 52% carbohydrate. The carbohydrate consisted of hexosamines, galactose, and fucose. Some of the carbohydrate in each of the jelly layers was covalently linked to protein through O-glycosidic bonds as beta elimination of the carbohydrate moiety in the presence of alkali was observed. In agreement with a previous finding, covalently attached sulfate was localized within the innermost jelly coat layer, J1. Cellulose acetate electrophoresis at pH 8.0 resolved a total of nine macromolecular components from the three jelly coat layers differentially staining for protein and carbohydrate: J1 yielded two anodically migrating components; the middle layer J2 yielded two cathodically migrating macromolecular components; the outermost layer J3 contained five species, three anodic and two cathodic. Sodium dodecyl sulfate agarose gel electrophoresis analysis yielded nine unique species, six of which stained coincidently for protein and carbohydrate. Immunoelectrophoresis and Ouchterlony double diffusion analyses using antiserum to total jelly components resolved nine different antigenic species with cross-reactivity between one or two macromolecules in layers J1 and J3. Analytical sedimentation velocity centrifugation revealed eight distinct species all of which exhibited hypersharp schlieren patterns and whose s20,w values were highly concentration dependent. On the basis of these analyses, Xenopus laevis egg jelly layers are composed of at least 8-9 distinct macromolecular species. The majority of these macromolecules are uniquely associated with different jelly coat layers.
非洲爪蟾卵的三个形态和功能各异的卵黄膜层J1、J2和J3，通过手工解剖分离，用二硫苏糖醇溶解，并进行了物理化学分析。这三个卵黄膜层的化学组成中蛋白质含量为37%至48%，碳水化合物含量为63%至52%。碳水化合物由己糖胺、半乳糖和岩藻糖组成。每个卵黄膜层中的一些碳水化合物通过O-糖苷键与蛋白质共价连接，因为在碱存在的情况下观察到碳水化合物部分的β消除。与之前的一项发现一致，共价连接的硫酸盐位于最内层的卵黄膜层J1内。在pH 8.0条件下进行的醋酸纤维素电泳从这三个卵黄膜层中分离出总共九个大分子成分，它们对蛋白质和碳水化合物进行了不同的染色：J1产生了两个向阳极迁移的成分；中间层J2产生了两个向阴极迁移的大分子成分；最外层J3包含五个种类，三个向阳极迁移，两个向阴极迁移。十二烷基硫酸钠琼脂糖凝胶电泳分析产生了九个独特的种类，其中六个对蛋白质和碳水化合物同时染色。使用针对总卵黄成分的抗血清进行免疫电泳和双向免疫扩散分析，分辨出九个不同的抗原种类，其中J1和J3层中的一两个大分子之间存在交叉反应。分析性沉降速度离心显示出八个不同的种类，所有这些种类都表现出超尖锐的纹影图案，并且它们的s20,w值高度依赖于浓度。基于这些分析，非洲爪蟾卵黄膜层由至少8 - 9个不同的大分子种类组成。这些大分子中的大多数与不同的卵黄膜层独特相关。
