Pb2+ biosorption by Serratia marcescens CCMA 1010 and its relation with zntR gene expression and ZntA efflux pump regulation

•S. marcescens CCMA 1010 biomass has high Pb2+ biosorption potential.•[Pb2+] up to 120 mg/L causes decay of zntR expression in S. marcescens CCMA 1010.•zntR expression decay coincides with less Pb2+ removal by active S. marcescens CCMA 1010.•The study contributes to a better understanding of the ZntA metals efflux protein regulation.