Pu Meng, Rowe-Magnus Dean Allistair
1Department of Molecular and Cellular Biochemistry, Indiana University of Bloomington, Bloomington, IN USA.
2Department of Biology, Indiana University Bloomington, Bloomington, IN USA.
NPJ Biofilms Microbiomes. 2018 Apr 23;4:10. doi: 10.1038/s41522-018-0052-7. eCollection 2018.
is autochthonous to estuaries and warm coastal waters. Infection occurs via open wounds or ingestion, where its asymptomatic colonization of seafood, most infamously oysters, provides a gateway into the human food chain. Colonization begins with initial surface contact, which is often mediated by bacterial surface appendages called pili. Type IV Tad pili are widely distributed in the Vibrionaceae, but evidence for a physiological role for these structures is scant. The genome codes for three distinct loci. Recently, a positive correlation was demonstrated between the expression of and the phenotypes of a descendent (NT) that exhibited increased biofilm formation, auto-aggregation, and oyster colonization relative to its parent. However, the mechanism by which pilus expression promoted these phenotypes was not determined. Here, we show that deletion of the pilin gene () altered the near-surface motility profile of NT cells from high curvature, orbital retracing patterns characteristic of cells actively probing the surface to low curvature traces indicative of wandering and diminished bacteria-surface interactions. The NT pilin mutant also exhibited decreased initial surface attachment, attenuated auto-aggregation and formed fragile biofilms that disintegrated under hydrodynamic flow. Thus, the locus, designated , promoted nitial surface attachment, uto-aggregation and resistance to echanical clearance of biofilms. The prevalence of loci in the Vibrionaceae suggests that they may play equally important roles in other family members.
原产于河口和温暖的沿海水域。感染通过开放性伤口或摄入发生，其在海鲜（最臭名昭著的是牡蛎）中的无症状定植为进入人类食物链提供了途径。定植始于最初的表面接触，这通常由称为菌毛的细菌表面附属物介导。IV型Tad菌毛广泛分布于弧菌科，但这些结构的生理作用证据不足。该基因组编码三个不同的位点。最近，已证明[具体基因名称]的表达与其后代（NT）的表型之间存在正相关，相对于其亲本，NT表现出生物膜形成增加、自聚集和牡蛎定植增加。然而，菌毛表达促进这些表型的机制尚未确定。在这里，我们表明菌毛蛋白基因（[具体基因名称]）的缺失改变了NT细胞的近表面运动模式，从主动探测表面的细胞特有的高曲率、轨道回溯模式变为指示游荡和细菌 - 表面相互作用减弱的低曲率轨迹。NT菌毛突变体还表现出初始表面附着减少、自聚集减弱，并形成在流体动力流下解体的脆弱生物膜。因此，指定为[具体名称]的[基因位点名称]促进了初始表面附着、自聚集和对生物膜机械清除的抗性。弧菌科中[基因位点名称]的普遍性表明它们可能在其他家族成员中发挥同样重要的作用。
