摩鹿加云斑蛛卵袋结构与纤维组成

采用扫描电子显微镜（SEM）和氨基酸自动分析仪对摩鹿加云斑蛛Cyrtophora moluccensis卵袋的结构和组成进行了观察研究.结果表明摩鹿加云斑蛛的卵袋呈椭球状,是由多种丝腺纺出的微米与纳米级的丝纤维形成的多个覆盖层构成的,包括白色框架、军绿色与灰白色外覆盖层和白色内覆盖层3部分.卵袋框丝与典型的拖牵丝氨酸组成基本相似,丙氨酸和甘氨酸的含量最丰富,分别约占39%和33%,其次是谷氨酸、丝氨酸和脯氨酸,分别约占7.8%、5.7%和3.6%;其余卵袋丝纤维的氨基酸组成与典型的柱状腺丝相似,与卵袋框丝相比,卵袋覆盖层的丝氨基酸的含量显著增加,约占21%,同时甘氨酸和脯氨酸的含量显著减少,分别约占12%和1%,并含有更多的极性和大侧链氨基酸,其丙氨酸的含量变化不大,仍占了27%左右.根据氨基酸组成与扫描电镜的结果综合分析了不同自径丝纤维的丝腺来源.

Structure and Fibrous Composition of the Spider Cyrtophora moluccensis Egg Case

The fibrous structures and composition of egg case of the spider （Cyrtophora moluccensis） were examined using SEM as well as amino acid analysis. The results demonstrated that its egg case is composed of multiple layers of silk, including the frame, outer cover, inner cover, consisting of different colored silk with diameters of between hundreds of nanometers and several micrometers. The amino acid composition was similar in the frame silk and typical dragline silk that the alanine （about 39%） and glycine （about 33 %） are the most abundant amino acids present, with glutamic acid （about 7.8 %）, serine （about 5.7 %） and prone （3.6%） occurring as the next most abundant. The amino acid composition of egg case cover silk was similar with typical cylindrical gland silk. In contrast to the frame silk, the all cover silk of egg case contained a significant increase in serine （about 21% ） content with a concomitant loss of glyeine （about 12 %） and prone （about 1%）, and contained more polar amino and large side acids. The gland origin of different diameters of silk fibers was analyzed using the results from SEM and amino acid composition studies.