Fig. 4.

Although growth of “Ca. L. asiaticus” was clearly detected in the biofilms, this pathogen is still a minor member of the biofilm community. a) “Ca. L. asiaticus”-containing biofilms grown in the MBRs appear orange. b) Inactivated inoculum led instead to accumulation of a white precipitate. c) Scanning electron micrographs of “Ca. L. asiaticus”-containing biofilms clearly show the presence of multiple microorganism types embedded within extracellular polymeric substance. d) Longer, rod-shaped bacteria with the same morphology as L. crescens are easily detectable as a minor biofilm component. e) Microbial community profiles of “Ca. L. asiaticus”-containing biofilm and planktonic cultures revealed that 65–73% of the population of the planktonic and biofilm cultures was Chryseobacterium species. The error bars represent the standard error of the mean of replicated experiments (n = 2). Significance was determined using a t-test (P < 0.05). (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)