Department of Physics, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden.
Adv Exp Med Biol. 2011;715:301-13. doi: 10.1007/978-94-007-0940-9_19.
Optical tweezers (OT) are a technique that, by focused laser light, can both manipulate micrometer sized objects and measure minute forces (in the pN range) in biological systems. The technique is therefore suitable for assessment of bacterial adhesion on an individual adhesin-receptor and single attachment organelle (pili) level. This chapter summarizes the use of OT for assessment of adhesion mechanisms of both non-piliated and piliated bacteria. The latter include the important helix-like pili expressed by uropathogenic Escherichia coli (UPEC), which have shown to have unique and intricate biomechanical properties. It is conjectured that the large flexibility of this type of pili allows for a redistribution of an external shear force among several pili, thereby extending the adhesion lifetime of bacteria. Systems with helix-like adhesion organelles may therefore act as dynamic biomechanical machineries, enhancing the ability of bacteria to withstand high shear forces originating from rinsing flows such as in the urinary tract. This implies that pili constitute an important virulence factor and a possible target for future anti-microbial drugs.
光学镊子（OT）是一种技术，通过聚焦激光，可以操纵微米大小的物体，并测量生物系统中的微小力（在皮牛顿范围内）。因此，该技术适用于评估单个黏附素-受体和单个附着细胞器（菌毛）水平上的细菌黏附。本章总结了 OT 在评估非菌毛和菌毛细菌黏附机制中的应用。后者包括尿路致病性大肠杆菌（UPEC）表达的重要螺旋菌毛，其具有独特而复杂的生物力学特性。据推测，这种菌毛的大柔韧性允许外部剪切力在几根菌毛之间重新分配，从而延长细菌的黏附寿命。因此，具有螺旋状黏附细胞器的系统可能充当动态生物力学机械装置，增强细菌抵抗源自冲洗流（如在泌尿道中）的高剪切力的能力。这意味着菌毛是一种重要的毒力因子，也是未来抗菌药物的一个可能靶点。
