Martinson Vincent G, Magoc Tanja, Koch Hauke, Salzberg Steven L, Moran Nancy A
Center for Insect Science, University of Arizona, Tucson, Arizona, USA Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, USA
Center for Computational Biology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
Appl Environ Microbiol. 2014 Jul;80(13):3793-803. doi: 10.1128/AEM.00322-14. Epub 2014 Apr 18.
Here, we report the genome of one gammaproteobacterial member of the gut microbiota, for which we propose the name "Candidatus Schmidhempelia bombi," that was inadvertently sequenced alongside the genome of its host, the bumble bee, Bombus impatiens. This symbiont is a member of the recently described bacterial order Orbales, which has been collected from the guts of diverse insect species; however, "Ca. Schmidhempelia" has been identified exclusively with bumble bees. Metabolic reconstruction reveals that "Ca. Schmidhempelia" lacks many genes for a functioning NADH dehydrogenase I, all genes for the high-oxygen cytochrome o, and most genes in the tricarboxylic acid (TCA) cycle. "Ca. Schmidhempelia" has retained NADH dehydrogenase II, the low-oxygen specific cytochrome bd, anaerobic nitrate respiration, mixed-acid fermentation pathways, and citrate fermentation, which may be important for survival in low-oxygen or anaerobic environments found in the bee hindgut. Additionally, a type 6 secretion system, a Flp pilus, and many antibiotic/multidrug transporters suggest complex interactions with its host and other gut commensals or pathogens. This genome has signatures of reduction (2.0 megabase pairs) and rearrangement, as previously observed for genomes of host-associated bacteria. A survey of wild and laboratory B. impatiens revealed that "Ca. Schmidhempelia" is present in 90% of individuals and, therefore, may provide benefits to its host.
在此，我们报告了肠道微生物群中一种γ-变形菌成员的基因组，我们将其命名为“候选施密德汉佩利亚蜂菌（Candidatus Schmidhempelia bombi）”，它是在对其宿主——凤蝶（Bombus impatiens）的基因组进行测序时意外测得的。这种共生菌是最近描述的细菌目Orbales的成员，该目细菌已从多种昆虫物种的肠道中分离得到；然而，“候选施密德汉佩利亚菌（Ca. Schmidhempelia）”仅在熊蜂中被发现。代谢重建显示，“候选施密德汉佩利亚菌”缺乏许多参与功能性NADH脱氢酶I的基因、所有参与高氧细胞色素o的基因以及三羧酸（TCA）循环中的大多数基因。“候选施密德汉佩利亚菌”保留了NADH脱氢酶II、低氧特异性细胞色素bd、厌氧硝酸盐呼吸、混合酸发酵途径和柠檬酸盐发酵，这些对于在蜜蜂后肠中发现的低氧或厌氧环境中生存可能很重要。此外，一个6型分泌系统、一个Flp菌毛和许多抗生素/多药转运蛋白表明它与宿主以及其他肠道共生菌或病原体之间存在复杂的相互作用。该基因组具有缩减（2.0兆碱基对）和重排的特征，这与之前观察到的宿主相关细菌的基因组特征一致。对野生和实验室饲养的凤蝶进行的一项调查显示，90%的个体中都存在“候选施密德汉佩利亚菌”，因此它可能对宿主有益。
