College of Food Science and Nutritional Engineering, China Agricultural University, 100083, Beijing, China.
Nat Commun. 2023 Nov 24;14(1):7650. doi: 10.1038/s41467-023-43352-6.
Eusocial pollinators are crucial elements in global agriculture. The honeybees and bumblebees are associated with a simple yet host-restricted gut community, which protect the hosts against pathogen infections. Recent genome mining has led to the discovery of biosynthesis pathways of bioactive natural products mediating microbe-microbe interactions from the gut microbiota. Here, we investigate the diversity of biosynthetic gene clusters in the bee gut microbiota by analyzing 477 genomes from cultivated bacteria and metagenome-assembled genomes. We identify 744 biosynthetic gene clusters (BGCs) covering multiple chemical classes. While gene clusters for the post-translationally modified peptides are widely distributed in the bee guts, the distribution of the BGC classes varies significantly in different bee species among geographic locations, which is attributed to the strain-level variation of bee gut members in the chemical repertoire. Interestingly, we find that Gilliamella strains possessing a thiopeptide-like BGC show potent activity against the pathogenic Melissococcus plutonius. The spectrometry-guided genome mining reveals a RiPP-encoding BGC from Gilliamella with a 10 amino acid-long core peptide exhibiting antibacterial potentials. This study illustrates the widespread small-molecule-encoding BGCs in the bee gut symbionts and provides insights into the bacteria-derived natural products as potential antimicrobial agents against pathogenic infections.
社会性传粉昆虫是全球农业的重要组成部分。蜜蜂和熊蜂与简单但宿主特异性的肠道群落相关，这些肠道群落可以保护宿主免受病原体感染。最近的基因组挖掘发现了肠道微生物群中介导微生物-微生物相互作用的生物活性天然产物生物合成途径。在这里，我们通过分析 477 株培养细菌和宏基因组组装基因组，研究了蜜蜂肠道微生物群中的生物合成基因簇的多样性。我们鉴定了 744 个生物合成基因簇（BGC），涵盖了多种化学类群。虽然经翻译后修饰的肽的基因簇广泛分布在蜜蜂肠道中，但 BGC 类别的分布在不同地理位置的不同蜜蜂物种中差异显著，这归因于蜜蜂肠道成员在化学组成中的菌株水平变化。有趣的是，我们发现具有硫肽样 BGC 的 Gilliamella 菌株对致病性 Melissococcus plutonius 表现出很强的活性。基于光谱法的基因组挖掘揭示了 Gilliamella 中一种 RiPP 编码 BGC，其核心肽长 10 个氨基酸，具有抗菌潜力。本研究说明了蜜蜂肠道共生菌中广泛存在的小分子编码 BGC，并为细菌来源的天然产物作为潜在的抗致病感染的抗菌剂提供了新的见解。
