Abstract
Showerheads support the development of multi-species biofilms that can be unsightly, produce malodor, and may harbor pathogens. The outer-surface spray-plates of many showerheads support visible biofilms that likely contain a mixture of bacteria from freshwater and potentially from human users. Coaggregation, a mechanism by which genetically distinct bacteria specifically recognize one another, may contribute to the retention and enrichment of different species within these biofilms. The aim of this work was to describe the bacterial composition of outer spray-plate biofilms of three domestic showerheads and to determine the intra- and inter-biofilm coaggregation ability of each culturable isolate. The bacterial composition of the three biofilms was determined by using bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP) and by culturing on R2A medium. An average of 31 genera per biofilm were identified using bTEFAP and a total of 30 isolates were cultured. Even though the microbial diversity of each showerhead biofilm differed, every cultured isolate was able to coaggregate with at least one other isolate from the same or different showerhead biofilm. Promiscuous coaggregating isolates belonged to the genera Brevundimonas, Micrococcus, and Lysobacter. This work suggests that coaggregation may be a common feature of showerhead biofilms. Characterization of the mechanisms mediating coaggregation, and the inter-species interactions they facilitate, may allow for novel strategies to inhibit biofilm development.
Highlights
IntroductionShowerheads can enrich for bacteria present in potable water by facilitating bacterial adhesion to exposed surfaces and to pre-attached bacteria (Feazel et al, 2009)
Showering is a common bathing method in the developed world (Chauvet et al, 1994)
Each showerhead biofilm possessed genera that were unique to that given showerhead (e.g. Enhydrobacter was present at 13.1% in shower head biofilm AH but absent in both other shower head biofilms)
Summary
Showerheads can enrich for bacteria present in potable water by facilitating bacterial adhesion to exposed surfaces and to pre-attached bacteria (Feazel et al, 2009). Over time, these adherent bacteria grow and recruit additional species on outer and inner surfaces to form complex, multi-species biofilm communities (Costerton et al, 1995). The development of showerhead biofilms has recently received increased attention because of the potential to enrich bacterial species including those that may have the ability to cause disease (Bauer et al, 2008; Exner et al, 2005; Falkinham et al, 2008; Nishiuchi et al, 2009; Schoen & Ashbolt, 2011). Understanding how bacteria form multispecies biofilms may allow for improved strategies to control their development on inner and outer showerhead surfaces
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
