Kaiwa Nahomi, Hosokawa Takahiro, Kikuchi Yoshitomo, Nikoh Naruo, Meng Xian Ying, Kimura Nobutada, Ito Motomi, Fukatsu Takema
Department of General Systems Studies, the University of Tokyo, Tokyo 153-8902, Japan.
Zoolog Sci. 2011 Mar;28(3):169-74. doi: 10.2108/zsj.28.169.
Microbiological characterization of gut symbiotic bacteria in a limited number of stinkbugs of the families Acanthosomatidae, Plataspidae, Pentatomidae, Scutelleridae, Parastrachiidae, Alydidae and Pyrrhocoridae has shown symbiotic association with midgut bacteria to be common in phytophagous taxa of these heteropteran insects. Here we investigated the midgut bacterial symbiont of Eucorysses grandis, a stinkbug of the family Scutelleridae. A specific gammaproteobacterium was consistently identified in insects from five different geographic origins. The bacterium was detected in 64 of 64 insects sampled from three host populations. Phylogenetic analyses revealed that the bacterium constitutes a distinct lineage in the Gammaproteobacteria, neither closely related to the gut symbiont of another scutellerid stinkbug, Cantao ocellatus, nor to gut symbionts of other stinkbugs. Diagnostic PCR, in situ hybridization and electron microscopy demonstrated that the bacterium is located extracelluarly, in the midgut fourth section, which possesses crypts. These results indicate that the primary gut symbionts have multiple evolutionary origins in the Scutelleridae. A Sodalis-allied facultative symbiont was also identified in some insects from natural populations. Biological aspects of the primary gut symbiont and the secondary Sodalis-allied symbiont are discussed.
对缘蝽科、龟蝽科、蝽科、盾蝽科、副盾蝽科、姬缘蝽科和红蝽科数量有限的椿象肠道共生细菌进行的微生物学特征分析表明，在这些异翅目昆虫的植食性类群中，中肠细菌的共生关联很常见。在此，我们研究了盾蝽科椿象巨蝽的中肠细菌共生体。在来自五个不同地理区域的昆虫中始终鉴定出一种特定的γ-变形菌。在从三个寄主种群采集的64只昆虫样本中均检测到了这种细菌。系统发育分析表明，该细菌在γ-变形菌中构成一个独特的谱系，既与另一种盾蝽科椿象眼斑广盾蝽的肠道共生体关系不密切，也与其他椿象的肠道共生体关系不密切。诊断性PCR、原位杂交和电子显微镜检查表明，该细菌位于中肠第四节的细胞外，该节有隐窝。这些结果表明，盾蝽科的主要肠道共生体有多个进化起源。在一些自然种群的昆虫中还鉴定出一种与索氏菌相关的兼性共生体。本文讨论了主要肠道共生体和次要的与索氏菌相关的共生体的生物学特性。
