Hirose Euichi, Murakami Akio
Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Nishihara, Okinawa 903-0213, Japan.
Zoolog Sci. 2011 Mar;28(3):199-205. doi: 10.2108/zsj.28.199.
Terpios hoshinota is a black-colored sponge encrusting both live and dead corals. On examination, we determined that in the mesohyl, unicellular cyanobacteria were distributed extracellularly in dense populations; roughly half of the area in the histological sections was occupied by the cyanobacterial cells in the mesohyl of the inner zone. Pigment extraction tests of whole sponges and microspectrophotometrical analysis of cyanobacterial symbionts showed that the black coloration of the sponge is attributable to extremely densely packed cyanobacteria expressing R-phycoerythrin. Spermatic follicles were found in the mesohyl of specimens collected in summer, indicating seasonal reproduction, which is likely to play a crucial role in long-distance dispersal. We also found a possible oocyte that did not contain cyanobacteria in the ooplasm.
霍氏角海绵是一种覆盖在活珊瑚和死珊瑚上的黑色海绵。经检查，我们确定在中胶层中，单细胞蓝细菌以密集群体的形式分布在细胞外；在组织切片中，大约一半的区域被内区中胶层的蓝细菌细胞占据。对整个海绵的色素提取测试以及对蓝细菌共生体的显微分光光度分析表明，海绵的黑色归因于表达R-藻红蛋白的极其密集的蓝细菌。在夏季采集的标本的中胶层中发现了精囊，表明存在季节性繁殖，这可能在远距离扩散中起关键作用。我们还在卵质中发现了一个可能不含蓝细菌的卵母细胞。
