Abstract
The present study was carried out for grouping and characterization of 60 natural isolates of psychrophihc and psychrotrophic vibrios isolated from deep-sea areas of the Western Pacific and Otsuchi Bay, where are located in northern Japan, using PCR-RFLP analysis of 16S rRNA genes. The 16S rRNA genes, about 1500bp long, were amplified by PCR and used to determine the genotypes and phylogenetic affiliation of 60 natural isolates Four tetramenc restriction enzymes (Hhal, Ddel, Rsal and 5aw3AI) were used for restriction fragment length polymorphism (RFLP) analysis. The 21 type and reference of the family Vibnonaceae were included in the analysis. A total of 81 strains were separated into 24 RFLP patterns Five groups were obtained from the genetic distance tree and results showed significant differences in the genotype composition between the isolates from the deep-sea and Otsuchi Bay. We observed two large phylogenetic groups in psychrophihc and psychrotrophic vibrios. One was Group 5 (the Vibrio marinus group) which was distributed only in the depths of the Western Pacific The other was Group 3 (the OC02 group) which was distributed in Otsuchi Bay.