Possible use of Serratia marcescens in toxic metal biosorption (removal)

Background, aim and scope Metal pollution is a serious problem for environmental safety and programmes of monitoring and bioremediation are needed. Among the processes of bioremediation, the use of microbes to remove and degrade contaminants is considered a biotechnological approach to clean up polluted environments. Aim The aim of this study was to evaluate the ability of Serratia marcescens in Pb, Cd and Cr removal and the potential use of these bacteria in toxic metal bioremediation from polluted environments. Methods A short-term study (120 min) was carried out to study the bacterial growth in the presence of sub-inhibitory concentrations of each metal analysed and the kinetics of metal biosorption in S. marcescens strain. In addition, metal influence on the biosynthesis of the red pigment 'prodigiosina' by S. marcescens was monitored. Results The results obtained in this study show metals biosorption by S. marcescens (range: 0.0133-0.213 mu g/g for Pb; 0.097-0.1853 mu g/g for Cd; and 0.105-0.176 mu g/g for Cr) and confirm the possible use of this bacterium to realize bioremediation processes, especially for Pb removal, and as a bioindicator of metal pollution.