Microbial interactions in drinking water biofilms

Abstract

Drinking water distribution networks may be viewed as a large reactor where a number of chemical and microbiological processes are taking place. Control of microbial growth in drinking water distribution systems (DWDS) often achieved through the addition of disinfectants, is essential to limit the spread of waterborne pathogens. However, microorganisms can resist disinfection through protection within biofilms and resistant host cells. Recent studies into the microbial ecology of DWDS have found that microbial resistance to disinfectants is affected by microbial community diversity and interspecies relationships. The dynamics of the microbial growth and multispecies biofilm formation in drinking water networks is very complex, as a large number of interacting processes are involved. Coaggregationlcoadhesion of microorganisms and other interspecies relationships are processes that are believed to play a significant role in the formation of single and multispecies biofilms in drinking water distribution systems, but remain poorly understood. Coaggregation is a process by which genetically distinct microorganisms become attached to one another via specific molecules and cumulative evidences suggest that such cell-cell adhesion influences the development of complex multispecies biofilms since aggregation conveys advantages to microorganisms.The purpose of this review is to gain deeper insights into the fundamental mechanisms of biofilm formation and population dynamics in DWDS.