OCEANOGRAPHIC SURVEY ON THE DISTRIBUTION OF TAKIKAWA'S SO-CALLED PATHOGENIC HALOPHILIC BACTERIA

Late in July 1961, the authors investigated on occurrence of TAKIKAWA's so-called pathogenic halophilic bacteria in the sea area around Izu Islands and Suruga bay aboard the Umitaka-maru, a research vessel of Tokyo University of Fisheries. Isolation of the organisms was carried out by the method according to SEKINE et al8). SEKINE et al8). had already isolated some strains of organisms having similar biological characteristics to those so-called pathogenic halophiles from natural environments, and showed that these organisms can be divided into two Groups, I and II. The present investigation revealed that a group of organisms having similar features to some extent to those afore-mentioned two groups are widely distributed in sea area. This group of organisms are easily differentiated from the Group I or II, and then they were classified as Group III. The distinctive characters between Group III and the other two groups were shown in Table 1. Throughout the sampling stations no organism belonging Group I in which so-called pathogenic halophiles are included could be detected, while Group II organisms were isolated only in coastal sea water. The Group III organisms were found to be widely distributed in both pelagic and coastal water irrespective of water depth. Group III organisms are regarded as marine inhabitant. The results obtained in the present survey may suggest that the so-called pathogenic halophilic bacteria is not distributed in the pelagic sea water around Kuroshio current. Regarding coastal sea area, however, further detailed studies on the distribution of the organisms is necessary.