Mercury Resistance in a Plasmid-Bearing Strain of Escherichia coli

Abstract

A strain of Escherichia coli carrying genes determining mercury resistance on a naturally occurring resistance transfer factor (RTF) converts 95% of 10 −5 m Hg 2+ (chloride) to metallic mercury at a rate of 4 to 5 nmoles of Hg 2+ per min per 10 8 cells. The metallic mercury is rapidly eliminated from the culture medium as mercury vapor. The volatilizing activity has a temperature dependence and heat sensitivity characteristic of enzymatic catalysis and is inducible by mercuric chloride. Ag + and Au 3+ are markedly inhibitory of mercury volatilization.