Abstract：
Termite hindguts are inhabited by symbionts that help with numerous processes, but changes in the gut microbiome due to season can potentially impact the physiology of termites. This study investigated the impact of seasonal changes on the composition of bacteria and protozoa in the termite gut. Termites were obtained monthly from May to October 2020 at a location in the central United States that typically experiences seasonal air temperatures ranging from < 0 to > 30 °C. The guts of 10 termites per biological replication were dissected and frozen within 1 day after collections. DNA was extracted from the frozen gut tissues and used for termite 16S rRNA mitochondrial gene analysis and bacterial 16S rRNA gene sequence surveys. Phylogenetic analysis of termite 16S rRNA gene sequences verified that the same colony was sampled across all time points. On processing bacterial 16S sequences, we observed alpha (observed features, Pielou\'s evenness, and Shannon diversity) and beta diversity (unweighted Unifrac, Bray-Curtis, and Jaccard) metrics to vary significantly across months. Based on the analysis of the composition of microbiomes with bias correction (ANCOM-BC) at the genus level, we found several significant bacterial taxa over collection months. In addition, Spearman correlation analysis demonstrated that 41 bacterial taxa were significantly correlated (positively and negatively) with average soil temperature. These results from a single termite colony suggest termite microbial communities go through seasonal changes in relative abundance related to temperature, although other seasonal effects cannot be excluded. Further investigations are required to conclusively define the consistency of microbial variation among different colonies with season.
摘要：
白蚁后背被共生体所居住，这些共生体有助于许多过程，但是由于季节的变化，肠道微生物组可能会影响白蚁的生理。这项研究调查了季节变化对白蚁肠道中细菌和原生动物组成的影响。从2020年5月至10月，每月在美国中部的一个地点获得白蚁，该地点通常经历<0至>30°C的季节性气温。每个生物复制10只白蚁的肠道在收集后1天内解剖并冷冻。从冷冻的肠道组织中提取DNA，并用于白蚁16SrRNA线粒体基因分析和细菌16SrRNA基因序列调查。白蚁16SrRNA基因序列的系统发育分析验证了在所有时间点均对相同的菌落进行采样。在处理细菌16S序列时，我们观察到α(观察到的特征，Pielou的均匀度，和香农多样性)和β多样性(未加权Unifrac，布雷-柯蒂斯,和Jaccard)的指标在不同月份之间差异很大。在属水平上对具有偏差校正（ANCOM-BC）的微生物组成进行分析的基础上，我们在收集的几个月里发现了几个重要的细菌分类群。此外,Spearman相关分析表明，41个细菌类群与平均土壤温度显着相关（正相关和负相关）。来自单个白蚁群落的这些结果表明，白蚁微生物群落经历了与温度相关的相对丰度的季节性变化，尽管不能排除其他季节性影响。需要进一步的调查才能最终确定不同菌落之间微生物随季节变化的一致性。
