Escherichia coli O157:H7 Requires Colonizing Partner to Adhere and Persist in a Capillary Flow Cell

Abstract

Bacteria exist in nature primarily in communities known as biofilms. These biofilms are usually characterized by differentiated structures, exhibit a different phenotype than their planktonic counterparts, and in nature most often consist of multispecies consortia (1, 2). An important process in shaping the formation and structure of some multispecies biofilms is the ability of certain species to coaggregate. In this process, planktonic cells adhere to genetically distinct cells in a biofilm or to other planktonic cells (3), thereby increasing biofilm formation. This process is growth-phase-dependent and is turned on and off by cells, suggestive that it may also play a role in dispersal and dissemination (4). Due to these and other complexities of the biofilm mode of growth, multiple species can coexist despite one organism having a much higher growth rate than another (5-7). In many cases, bacteria have been shown to gain a fitness advantage when residing in a mixed-species versus single-