Vieira Alexsandro S, Ramalho Manuela O, Martins Cintia, Martins Vanderlei G, Bueno Odair C
Centro de Estudos de Insetos Sociais, UNESP - Univ Estadual Paulista, Campus Rio Claro, Av. 24A, 1515, Bela Vista, Rio Claro, São Paulo, 13506-900, Brazil.
Universidade Federal do Piauí - Campus Ministro Reis Velloso, Av. São Sebastião, 2819, Parnaíba, Piauí, 64.202-020, Brazil.
Curr Microbiol. 2017 Oct;74(10):1216-1225. doi: 10.1007/s00284-017-1307-x. Epub 2017 Jul 18.
Bacterial endosymbionts are common in all insects, and symbiosis has played an integral role in ant evolution. Atta sexdens rubropilosa leaf-cutting ants cultivate their symbiotic fungus using fresh leaves. They need to defend themselves and their brood against diseases, but they also need to defend their obligate fungus gardens, their primary food source, from infection, parasitism, and usurpation by competitors. This study aimed to characterize the microbial communities in whole workers and different tissues of A. sexdens rubropilosa queens using Ion Torrent NGS. Our results showed that the microbial community in the midgut differs in abundance and diversity from the communities in the postpharyngeal gland of the queen and in whole workers. The main microbial orders in whole workers were Lactobacillales, Clostridiales, Enterobacteriales, Actinomycetales, Burkholderiales, and Bacillales. In the tissues of the queens, the main orders were Burkholderiales, Clostridiales, Syntrophobacterales, Lactobacillales, Bacillales, and Actinomycetales (midgut) and Entomoplasmatales, unclassified γ-proteobacteria, and Actinomycetales (postpharyngeal glands). The high abundance of Entomoplasmatales in the postpharyngeal glands (77%) of the queens was an unprecedented finding. We discuss the role of microbial communities in different tissues and castes. Bacteria are likely to play a role in nutrition and immune defense as well as helping antimicrobial defense in this ant species.
细菌内共生体在所有昆虫中都很常见，共生在蚂蚁的进化过程中发挥了不可或缺的作用。塞氏切叶蚁（Atta sexdens rubropilosa）利用新鲜树叶培育它们的共生真菌。它们需要保护自己和后代免受疾病侵害，同时还需要保护它们唯一的真菌园（这是它们的主要食物来源）免受感染、寄生以及竞争者的侵占。本研究旨在利用Ion Torrent二代测序技术对塞氏切叶蚁蚁后的整个工蚁个体及不同组织中的微生物群落进行特征分析。我们的结果表明，中肠中的微生物群落在丰度和多样性上与蚁后咽后腺及整个工蚁个体中的微生物群落有所不同。整个工蚁个体中的主要微生物目为乳杆菌目、梭菌目、肠杆菌目、放线菌目、伯克霍尔德氏菌目和芽孢杆菌目。在蚁后的组织中，主要目为伯克霍尔德氏菌目、梭菌目、互营杆菌目、乳杆菌目、芽孢杆菌目和放线菌目（中肠）以及昆虫支原体目、未分类的γ-变形菌纲和放线菌目（咽后腺）。在蚁后的咽后腺中昆虫支原体目丰度很高（77%），这是一个前所未有的发现。我们讨论了微生物群落在不同组织和蚁群等级中的作用。细菌可能在这种蚂蚁的营养、免疫防御以及协助抗菌防御方面发挥作用。
