Bacteria utilize type IV pili (T4P) to interact with their environment, where they facilitate processes including motility, adherence, and DNA uptake. T4P require multisubunit, membrane-spanning nanomachines for assembly. The tight adherence (Tad) pili are an Archaea-derived T4P subgroup whose machinery exhibits significant mechanistic and architectural differences from bacterial type IVa and IVb pili. Most Tad biosynthetic genes are encoded in a single locus that is widespread in bacteria due to facile acquisition via horizontal gene transfer. These loci experience extensive structural rearrangements, including the acquisition of novel regulatory or biosynthetic genes, which fine-tune their function. This has permitted their integration into many different bacterial lifestyles, including the cell cycle, predation, and numerous plant and mammalian pathogens and symbionts.

中文翻译：

---

IVc 型菌毛：略有不同

细菌利用 IV 型菌毛 (T4P) 与环境相互作用，促进运动、粘附和 DNA 摄取等过程。 T4P 需要多亚基、跨膜纳米机器进行组装。紧密粘附 (Tad) 菌毛是古细菌衍生的 T4P 亚群，其机械结构与 IVa 和 IVb 型细菌菌毛表现出显着的机械和结构差异。大多数 Tad 生物合成基因都编码在单个基因座中，由于通过水平基因转移很容易获得，该基因座广泛存在于细菌中。这些基因座经历了广泛的结构重排，包括获得新的调节或生物合成基因，从而微调它们的功能。这使得它们能够融入许多不同的细菌生活方式，包括细胞周期、捕食以及许多植物和哺乳动物病原体和共生体。