不同生境和不同性别黄胸木蜂成虫肠道微生物的多样性和功能预测

Diversity and functional prediction of gut microbiota in adults Xylocopa appendiculata from different habitats and sexes

摘要:

目的 明确重要野生传粉昆虫黄胸木蜂(Xylocopa appendiculata)肠道微生物的多样性特征，为野生传粉昆虫资源的保护与利用提供理论依据。方法 基于16S rRNA基因高通量测序技术，对采自不同生境和不同性别的黄胸木蜂成虫肠道微生物多样性进行比较分析，并对其微生物群落功能进行预测。结果 黄胸木蜂成虫肠道菌群主要由芽孢杆菌门(Bacillota) (相对丰度50.17%)、假单胞菌门(Pseudomonadota) (相对丰度32.04%)、放线菌门(Actinomycetota) (相对丰度12.84%)和拟杆菌门(Bacteroidota) (相对丰度3.77%)组成。其中，乳杆菌属(Lactobacillus)作为核心菌群存在于所有被检测的黄胸木蜂样本中。不同生境和不同性别黄胸木蜂成虫肠道菌群的相对丰度存在差异，隋唐的成虫(HXST)肠道微生物群落丰富度、多样性和均匀度均最高；隋唐(ST)和曹窑(CY)的雌性成虫肠道微生物群落丰富度、多样性和均匀度均高于雄性，水泉(SQ)的雄性成虫肠道微生物群落丰富度、多样性和均匀度均高于雌性。吉列姆氏菌属(Gilliamella)作为曹窑雄性成虫(HXCYM)的优势菌属，在其他样本中占比极小。PICRUSt2功能预测分析结果表明，黄胸木蜂成虫肠道微生物群落中代谢通路占比高达74.00%。结论 黄胸木蜂成虫肠道菌群表现出与社会性蜜蜂[如西方蜜蜂(Apis mellifera)和熊蜂属(Bombus spp.)]相似的生态适应特征，其微生物群落具有低多样性、高度保守且特化的核心菌群结构。环境异质性和宿主性别可能是驱动肠道菌群分异的关键生态因子。黄胸木蜂肠道菌群可能在维持宿主能量稳态及种群适应性中发挥核心作用。

Abstract:

Objective To clarify the diversity characteristics of gut microbiota in the important wild pollinator, Xylocopa appendiculata, and provide theoretical basis for the conservation and utilization of wild pollinator resources.Methods Utilizing employed 16S rRNA gene high-throughput sequencing, we conducted comparative analyses of gut microbiota diversity in adults X. appendiculata from different habitats and sexes. Functional prediction of gut microbial communities was performed using PICRUSt2.Results The gut microbiota in adults X. appendiculata was predominantly composed of Bacillota (relative abundance of 50.17%), Pseudomonadota (relative abundance of 32.04%), Actinomycetota (relative abundance of 12.84%), and Bacteroidota (relative abundance of 3.77%). The genus Lactobacillus was identified as a core microbiota present in all sampled individuals. Significant differences in the relative abundance of gut microbiota were observed across habitats and sexes. The samples from the Sui and Tang Dynasties City Ruins Botanical Garden habitat (HXST) exhibited the highest richness, diversity, and evenness of gut microbiota. In the Sui and Tang Dynasties City Ruins Botanical Garden habitat (ST) and the Caoyao Village habitat (CY), female adults showed higher microbial richness, diversity, and evenness compared to males. In the Shuiquan Village habitat (SQ), male adults showed higher microbial richness, diversity, and evenness compared to females. The genus Gilliamella, as the dominant genus of male samples from Caoyao Village (HXCYM), accounts for a very small proportion in other samples. Functional prediction PICRUSt2 showed that the metabolic gene functions of the gut microbiota of adults X. appendiculata are the most enriched, with an abundance ratio of 74.00%.Conclusion The gut microbiota of adults X. appendiculata exhibits ecological adaptive features with social bees (e.g., Apis mellifera and Bombus spp.), characterized by low diversity, highly conservation, and specialized core microbial community structure. Environmental heterogeneity and host sex were identified as key drivers of gut microbiota divergence. These findings suggest that the gut microbiota of X. appendiculata may play a central role in maintaining host energy homeostasis and population adaptability.