Differences in the Diversity and Structure of the Gut Microbiome in Different Life Stages of the American Cockroach (Periplaneta americana)

Abstract Gut microbes play critical roles in host nutrition, physiology, and behavior. Periplaneta americana is a famous urban pest which is widely distributed in the tropics and subtropics, but very few information is available on the gut microbiome of Periplaneta americana, particularly in its different life stages. Here, we characterized the diversity and structure of gut microbiome in eggs, nymph and adult life stages of Periplaneta americana using high-throughput 16S rRNA genes sequencing. Both the results of Alpha- and Beta-diversity analysis showed the diversity and structure of gut microbiome were significant different among the eggs, nymph and adult stages. The result of species distribution showed the predominant phyla in three life stages were Bacteroidetes , Firmicutes and Proteobacteria , but the relative abundances of these bacteria were significant different among each life stage. 1,169 operational taxonomic units were shared by three stages, which indicating the gut microbiome may be inherited to offspring from parents of Periplaneta americana. According to the prediction of functional genes in metabolic pathways, most of them were distributed in the metabolic pathways of basic physiology such as nutrition, growth, development and immunity, etc. The relative abundances of functional genes in metabolic pathways were significant different among life stages of Periplaneta americana, indicating the gut microbiome might play an important role in the physiology across its different life stages. This study revealed the diversity and structure of gut microbiome in different life stages of Periplaneta americana, which may contribute to us to understand it’s physiology and behaviors.