Characterization of bacterial biofilms formed on As(V)-containing water

S.E. RASTELLI; B.M. ROSALES; M.R. VIERA

Ciudad Autónoma de Buenos Aires

Congreso; 5th International Congress on Arsenic in the Environment; 2014

International Society of Groundwater for Sustainable ÑDevelopment (ISGSD)

Microorganisms, particularly those associated to surface (sessile microorganisms) play a rolein the process of arsenic mobilization. Several studies have shown theexistance of specific genes associated to arsenic resistance in microorganismsexposed to arsenic environments. The aim of this work was to study thetolerance to As(V) of sessile bacteria grown on drinking water distributionmaterials in the presence of As(V). Bacterial counts on Fe and Zn were higher than thoseobtained on Cu and PP and they were higher in the presence of As. CulturableAs-tolerant bacteria able to grow in the presence of high As(V) concentration(up to 1000mg/L) were obtained from all the biofilms except Cu-biofilms, which grew in the presence of up to 300mg/L. Seventeen differentspecies were identified: 64% Bacilli, 12% alfa-Proteobacteria and Actinobacteria, 6% beta-Proteobacteria and gamma-Proteobacteria. The arsC gene was detected in several sessile communities and bacterial isolates.