Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CCT-La Plata-CONICET, Casilla de Correo 16, Sucursal 4, (1900) La Plata, Argentina.
Colloids Surf B Biointerfaces. 2011 Feb 1;82(2):536-42. doi: 10.1016/j.colsurfb.2010.10.013. Epub 2010 Oct 15.
Biofilm development involves several stages and flagellar expression of bacteria is considered an important factor in this process. However, its role in the earliest stage of biofilm development is not yet clear. In order to analyse this topic, Pseudomonas fluorescens samples were trapped on a patterned gold surface with sub-microtrenches (ST) so as to hinder their motility, and nanostructured gold with random orientation (SR) was used as control substrate. Atomic force microscopic (AFM) observations were made on untreated samples. Initially, ca. 75% of the flagella on ST and 85% of flagella on SR are oriented towards the neighbouring bacteria. Some of them made contact and surrounded the cells. Subsequently, 2-D raft structures formed on SR inert substrates with lateral curly flagella, while those at the poles of the rafts turned towards the nearest cell group. A few flagella and the formation of 3-D bacterial structures were observed on toxic substrates like copper. Results showed that patterned substrates are suitable tools to detect the orientation of flagella in the earliest stage of biofilm formation on solid opaque surfaces avoiding sample pre-treatment.
生物膜的形成涉及多个阶段，细菌鞭毛的表达被认为是这个过程中的一个重要因素。然而，其在生物膜形成的最早阶段的作用尚不清楚。为了分析这个课题，将荧光假单胞菌样品困在具有亚微米沟槽（ST）的图案化金表面上，以阻碍其运动，并使用具有随机取向的纳米结构金（SR）作为对照基底。对未经处理的样品进行原子力显微镜（AFM）观察。最初，ST 上约 75%的鞭毛和 SR 上 85%的鞭毛都朝向邻近的细菌。其中一些鞭毛发生接触并包围了细胞。随后，在惰性 SR 基底上形成了 2-D 筏结构，侧向卷曲的鞭毛，而筏子的两极则朝向最近的细胞群。在像铜这样的毒性基底上观察到了一些鞭毛和 3-D 细菌结构的形成。结果表明，图案化基底是在固体不透明表面上形成生物膜的最早阶段检测鞭毛取向的合适工具，避免了样品预处理。
