Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia.
Grupo de Biología y Control de Enfermedades Infecciosas, Universidad de Antioquia, Medellín, Colombia.
PLoS One. 2020 Nov 12;15(11):e0240916. doi: 10.1371/journal.pone.0240916. eCollection 2020.
Triatomines (Hemiptera: Reduviidae) are the insect vectors of Trypanosoma cruzi, the causative agent of Chagas disease. The gut bacterial communities affect the development of T. cruzi inside the vector, making the characterization of its composition important in the understanding of infection development. We collected 54 triatomine bugs corresponding to four genera in different departments of Colombia. DNA extraction and PCR were performed to evaluate T. cruzi presence and to determine the discrete typing unit (DTU) of the parasite. PCR products of the bacterial 16S rRNA gene were pooled and sequenced. Resulting reads were denoised and QIIME 2 was used for the identification of amplicon sequence variants (ASVs). Diversity (alpha and beta diversity) and richness analyses, Circos plots, and principal component analysis (PCA) were also performed. The overall T. cruzi infection frequency was 75.9%, with TcI being the predominant DTU. Approximately 500,000 sequences were analyzed and 27 bacterial phyla were identified. The most abundant phyla were Proteobacteria (33.9%), Actinobacteria (32.4%), Firmicutes (19.6%), and Bacteroidetes (7.6%), which together accounted for over 90% of the gut communities identified in this study. Genera were identified for these main bacterial phyla, revealing the presence of important bacteria such as Rhodococcus, Serratia, and Wolbachia. The composition of bacterial phyla in the gut of the insects was significantly different between triatomine species, whereas no significant difference was seen between the state of T. cruzi infection. We suggest further investigation with the evaluation of additional variables and a larger sample size. To our knowledge, this study is the first characterization of the gut bacterial structure of the main triatomine genera in Colombia.
锥蝽（半翅目：锥蝽科）是克氏锥虫的昆虫传播媒介，克氏锥虫是恰加斯病的病原体。肠道细菌群落影响寄生虫在媒介体内的发育，因此，对其组成的特征描述对于理解感染的发展非常重要。我们收集了来自哥伦比亚四个不同地区的 54 只锥蝽，对应四个属。进行 DNA 提取和 PCR 以评估 T. cruzi 的存在，并确定寄生虫的离散型单位（DTU）。对细菌 16S rRNA 基因的 PCR 产物进行合并和测序。对产生的读数进行去噪，然后使用 QIIME 2 来鉴定扩增子序列变异（ASV）。还进行了多样性（alpha 和 beta 多样性）和丰富度分析、Circos 图和主成分分析（PCA）。总的 T. cruzi 感染频率为 75.9%，主要 DTU 为 TcI。分析了大约 50 万个序列，并鉴定了 27 个细菌门。最丰富的门是变形菌门（33.9%）、放线菌门（32.4%）、厚壁菌门（19.6%）和拟杆菌门（7.6%），它们共同占本研究中鉴定的肠道群落的 90%以上。确定了这些主要细菌门的属，揭示了一些重要细菌的存在，如罗得西亚杆菌属、沙雷氏菌属和沃尔巴克氏体属。昆虫肠道中细菌门的组成在不同的锥蝽种之间存在显著差异，而 T. cruzi 感染状态之间没有显著差异。我们建议进一步调查，评估更多的变量和更大的样本量。据我们所知，这是首次对哥伦比亚主要锥蝽属肠道细菌结构进行的特征描述。
