Effect of Coordination Structure of Werner-type Metal Complexes on Bioluminescence Intensity of Marine Luminescent Bacterium Vibrio fischeri

Abstract

This study aimed to investigate the effect of coordination structure of Werner-type metal complexes on the bioluminescence intensity of marine luminescent bacterium Vibrio fischeri. Octahedral complexes of Co²⁺, Zn²⁺ and Cu²⁺ were prepared by mixing with varied concentrations of aqueous ethylenediamine or glycine as a ligand and the bioluminescence intensity of Vibrio fischeri was measured using ROTAS^TM-leachable kit. Toxicity of metal ion was apparently decreased by formation of complexes with ethylenediamine and the effect depended on the kind of metal ion and coordination structure. Meanwhile, although the toxicity was also reduced by the formation of glycine complexes, no clear dependency was found on the coordination structure, probably because of bioavailability of glycine for Vibrio fischeri via Na⁺-symport system in cell membrane.