Characterization of a facultatively psychrophilic bacterium, Vibrio rumoiensis sp. nov., that exhibits high catalase activity

A novel facultatively psychrophilic bacterium, strain S-1, which exhibits e xtraordinarily high catalase activity was isolated from the drain pool of a fish product processing plant that uses H2O2 as a bleaching and microbicid al agent. The catalase activity of the isolate was 1 or 2 orders of magnitu de higher than those of Corynebacterium glutamicum, Staphylococcus aureus, Pseudomonas fluorescens, and five other species tested in this study. The s train seemed to possess only one kind of catalase, according to the results of polyacrylamide gel electrophoresis of the cell extract, The optimum tem perature for catalase activity was about 30 degrees C, which was about 20 d egrees C lower than that for bovine catalase activity. Electron microscopic observation revealed that the surface of the microorganism was covered by blebs, Although the isolate was nonflagellated, its taxonomic position on t he basis of physiological and biochemical characteristics and analysis of 1 6S rRNA sequence and DNA-DNA relatedness data indicated that strain S-l is a new species belonging to the genus Vibrio. Accordingly, we propose the na me Vibrio rumoiensis. The type strain is S-l (FERM P-14531).