Uptake of zinc in Pseudomonas sp. strain UDG26

Abstract

Zinc resistance in Pseudomonas sp. strain UDG26 was inducible. Induction led to enhanced uptake of the metal. A zinc-sensitive variant (UDG86) took up significantly less metal ion than the resistant one did. The affinity of uninduced and sensitive cells to zinc was less than that of resistant, induced cells. Metal accumulation by induced cells was not inhibited by azide, while 2,4-dinitrophenol and N-N'-dicyclohexylcarbodiimide enhanced zinc uptake because of inhibition of efflux. Transcription and translation inhibitors drastically reduced zinc accumulation, bringing it to the level found in the sensitive strain. These results suggest the involvement of protein(s) in zinc resistance.