云南省腾冲市3种常见蚊虫细菌群落结构及多样性研究

Study on bacterial community structure and diversity of 3 common mosquitoes in Tengchong City,Yunnan Province

目的探究腾冲市常见蚊虫自然携带的细菌群落结构多样性以及未知细菌。方法从云南省腾冲市同一地点随机捕捉的3种蚊虫,分别为中华按蚊、三带喙库蚊、致倦库蚊。应用Illumina NovaSeq测序平台对这3种蚊虫自然携带的细菌16S rRNA基因的V4高变区进行高通量测序,将测序数据进行处理分析后用于细菌微生物群落结构及多样性的分析和未知细菌的探究。结果获得可用于后续分析的OTU数目为2866个,通过绘制稀释曲线,可以看出本次的测序深度能充分反映这3种蚊虫的实际菌群结构。3种蚊虫及各组样品间既有共有的OTUs,也有特有的OTUs;Alpha和Beta多样性分析显示各蚊种及各组样品之间的物种组成丰度与相似性存在差异,其中中华按蚊的菌群丰度和多样性高于其他两种蚊虫,而三带喙库蚊和致倦库蚊的物种组成较为相似。通过对3种蚊虫菌群结构的分析,在门水平上,变形菌门、厚壁菌门、未明确细菌和放线菌门均是各蚊种共有的优势菌群,但在各蚊种中相对丰度存在差异;在属水平上,各蚊种的优势菌属及其相对丰度均存在显著差异。同时发现菌群中存在葡萄球菌属、变形杆菌属、无形体属、支原体属等大量的致病菌和条件致病菌,以及未知细菌。结论在同一环境下,不同蚊种及同一蚊种不同个体分组之间的细菌微生物群落结构和多样性存在显著差异,同时各蚊种均携带了致病菌和未知细菌,对该地区的公共卫生安全具有潜在的隐患。

Objective To investigate the bacterial community structure diversity and unknown bacteria naturally carried by common mosquitoes in Tengchong City.Methods The 3 species of mosquitoes were randomly captured from cattle houses around Tengchong port in Yunnan Province and identified as Anopheles sinensis,Culex tritaeniorhynchus and Culex quinquefasciatus.Each sample DNA genome was extracted by CTAB method,and Illumina NovaSeq sequencing platform was used for high-throughput sequencing of the 3 species of mosquitoes bacterial 16 S rRNA V4 region.The sequencing data were processed and spliced for the analysis of bacterial community structure diversity and the exploration of unknown bacterial.Results A total of 559322 high-quality splicing Tags and 2866 OTUs were obtained in this study.Rarefaction curves indicated that the sequencing depth of this time could fully reflect the actual bacterial community structure of the 3 species of mosquitoes.The 1150 OTUs were common among the 3 species of mosquitoes,and the number of OTUs unique to An.sinensis was up to 425.There were also common OTUs and specific OTUs among each group of samples.The results showed that there were differences in the richness and similarity of species composition among mosquito species and sample groups.Alpha diversity analysis showed that the bacterial community abundance and diversity of An.sinensis were higher than in the other two species.Beta diversity analysis showed that the species composition of Cx.tritaeniorhynchus and Cx.quinquefasciatus were similar.Based on bacterial community structure analysis of the 3 species of mosquitoes,Proteobacteria,Firmicutes,unidentified_Bacteria and Actinobacteriota were the dominant bacterial at the phylum level,but there were differences in relative abundance among mosquito species.At the genus level,there were significant differences in the dominant bacterial genera and relative abundance of each mosquito species.Staphylococcus was the dominant genus of the 3 mosquito species.Meanwhile,a large number of pathogenic bacteria and conditionally pathogenic bacteria,as well as unknown bacteria,were found in the mosquito samples,such as Staphylococcus,Proteus,Anaplasma and Mycoplasma.Conclusion In the same environment,there were significant differences in bacterial community structure and diversity among different mosquito species and different individual groups of the same mosquito species.At the same time,all mosquito species carried pathogenic bacteria and unknown bacteria,which had a potential hazard to public health safety in the area.