Symbiosis and Insect Diversification: an Ancient Symbiont of Sap-Feeding Insects from the Bacterial Phylum Bacteroidetes

作者：Nancy A. Moran, Phat L Tran, Nicole M. Gerardo · 发表于：Applied and Environmental Microbiology · 年份：2005 · DOI：10.1128/aem.71.12.8802-8810.2005 · 被引用次数：404 · 研究领域：Insect symbiosis and bacterial influences、Plant and animal studies、Phytoplasmas and Hemiptera pathogens

Several insect groups have obligate, vertically transmitted bacterial symbionts that provision hosts with nutrients that are limiting in the diet. Some of these bacteria have been shown to descend from ancient infections. Here we show that the large group of related insects including cicadas, leafhoppers, treehoppers, spittlebugs, and planthoppers host a distinct clade of bacterial symbionts. This newly described symbiont lineage belongs to the phylum Bacteroidetes. Analyses of 16S rRNA genes indicate that the symbiont phylogeny is completely congruent with the phylogeny of insect hosts as currently known. These results support the ancient acquisition of a symbiont by a shared ancestor of these insects, dating the original infection to at least 260 million years ago. As visualized in a species of spittlebug (Cercopoidea) and in a species of sharpshooter (Cicadellinae), the symbionts have extraordinarily large cells with an elongate shape, often more than 30 mum in length; in situ hybridizations verify that these correspond to the phylum Bacteroidetes. "Candidatus Sulcia muelleri" is proposed as the name of the new symbiont.