Guimaraes Helena Ipe Pinheiro, Santana Renata Henrique, Silveira Rafaella, Pinto Otavio Henrique Bezerra, Quirino Betania Ferraz, Barreto Cristine Chaves, Bustamante Mercedes Maria da Cunha, Krüger Ricardo Henrique
Cellular Biology Department, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília D.F. 70910-900, Brazil.
Brazilian Federal Institute, Campus Planaltina, Brasília D.F. 70910-900, Brazil.
Microorganisms. 2020 Sep 27;8(10):1482. doi: 10.3390/microorganisms8101482.
Eusocial animals, such as the termites, often build a nest-like structure called a mound that provides shelter with stable internal conditions and protection against predators. Termites are important components of the Brazilian Cerrado biota. This study aimed to investigate the bacterial community composition and diversity of the termite-mound soil using culture-independent approaches. We considered the vertical profile by comparing two different mound depths (mound surface and 60 cm) and seasonality with samplings during the rainy and dry seasons. We compared the mound soil microbiota to the adjacent soil without the influence of the mound to test the hypothesis that the Cerrado soil bacterial community was more diverse and more susceptible to seasonality than the mound soil microbiota. The results support the hypothesis that the Cerrado soil bacterial community is more diverse than the mound soil and also has a higher variability among seasons. The number of observed OTUs (Operational Taxonomic Units) was used to express bacterial richness, and it indicates that soil moisture has an effect on the community distribution and richness of the Cerrado samples in comparison to mound samples, which remain stable across seasons. This could be a consequence of the protective role of the mound for the termite colony. The overall community taxonomic profile was similar between soil samples, especially when compared to the taxonomic composition of the termite's gut, which might be explained by the different characteristics and functionality between the soil and the gut microbial community.
群居性动物，如白蚁，常常建造一种称为蚁丘的巢状结构，这种结构能提供具有稳定内部条件的庇护所，并抵御捕食者。白蚁是巴西塞拉多生物群的重要组成部分。本研究旨在采用非培养方法调查白蚁丘土壤的细菌群落组成和多样性。我们通过比较两个不同的蚁丘深度（蚁丘表面和60厘米深处）以及雨季和旱季的采样来考虑垂直剖面。我们将蚁丘土壤微生物群与不受蚁丘影响的相邻土壤进行比较，以检验塞拉多土壤细菌群落比蚁丘土壤微生物群更加多样且对季节性变化更敏感这一假设。结果支持了塞拉多土壤细菌群落比蚁丘土壤更加多样且在不同季节间具有更高变异性这一假设。观察到的OTU（操作分类单元）数量用于表示细菌丰富度，这表明与蚁丘样本相比，土壤湿度对塞拉多样本的群落分布和丰富度有影响，而蚁丘样本在不同季节保持稳定。这可能是蚁丘对蚁群起到保护作用的结果。土壤样本之间的总体群落分类概况相似，尤其是与白蚁肠道的分类组成相比时，这可能是由土壤和肠道微生物群落不同的特征和功能所解释的。
