Facultative psychrophilic bacteria isolated from the tropical districts in Indonesia.

Abstract

In this study the bacteria inverstigated were 34 strains (P-1∼P-34) isolated at 4∼5°C by enrichment culture in Indonesia. These strains were divided into 7 subgroups (Group I∼Group VII) from the results of cultural, morphological, temperature dependency of growth, biophysical investigations and cellular fatty acid composition. Group I includes 5 strains, of which one strain was mesophile and four strains were facultative psychrophiles. Group II includes 4 strains, which were concluded to be in the genus Sporosarcina and to have high salt concentration dependency of growth. Group III includes 2 strains, which showed rhizoid rough colony formation and were considered to be in the genus Alcaligenes or Flavobacterium. The relation with salt was considered to be interesting as a growth factor in this Group. Group IV includes 10 strains, of which only one strain was mesophile and remaining 9 strains were facultative psychrophiles. These strains were considered to be in the genus Alcaligenes or Pseudomonas. Their sources were distributed over very wide range.Group V includes 7 strains, and Group VI includes 3 strains, all of which were considered as facultative psychrophile. Their optimum growth temperature were low (4∼27°C). Group VII includes 9 strains, all of which were considered to be in the genus Pseudomonas. In conclusion, there were no obligate psychrophlile and 23 strains were facultative psychrophile. In the case of Group VI and VII, the growth investigation and analyses of fatty acid composition by gas chromatography were carried out. As the results of these precise examinations, Group VI was considered to be very near to the genus Moraxella or Acinetobacter, and Group VII near to the geuns Chromobacterium or Pseudomonas. On the level of species determination, it was concluded that P-26, P-27 and P-33 were the same species near to Pseudomonas caryophylli, and P-6, P-31 and P-29 were considered as Moraxella bovis or Moraxella-Like-species.