A biofilm is a layer of microbes that have aggregated to form a colony. The colony attaches to a surface with a slime layer which protects the microorganisms, promoting their growth and survival. Biofilms occur in various environments such as soils, sediments, wastewater, water pipelines, water purifying systems, cooling water systems, medical devices, archaeological monuments, marine vessels, and hospitals. Biofilms may induce adverse effects such as fostering drug-resistant strains. Here, we review biofilms with focus on their formation, occurrence in water systems, impact, microbial interactions, and characterization methods. Communication includes cell-to-cell interactions by quorum sensing, interactions mediated by flagella, gene, and signaling molecules, and interactions mediated by extracellular polymeric substances. Characterization methods comprise surface-enhanced Raman scattering spectroscopy, confocal laser scanning microscopy, scanning electron microscopy, fluorescence microscopy, sensors, and metagenomics analysis.

生物膜是聚集形成菌落的一层微生物。菌落附着在具有粘液层的表面上，该粘液层可以保护微生物，促进其生长和生存。生物膜存在于各种环境中，例如土壤、沉积物、废水、输水管道、净水系统、冷却水系统、医疗设备、考古遗迹、船舶和医院。生物膜可能会引起不良反应，例如培育耐药菌株。在这里，我们回顾生物膜，重点关注其形成、在水系统中的发生、影响、微生物相互作用和表征方法。通讯包括通过群体感应实现的细胞间相互作用、由鞭毛、基因和信号分子介导的相互作用以及由细胞外聚合物介导的相互作用。表征方法包括表面增强拉曼散射光谱、共焦激光扫描显微镜、扫描电子显微镜、荧光显微镜、传感器和宏基因组分析。