Protease-Producing Psychrotolerant Bacteria Isolated from Arctic Environment

Abstract

For screening of new proteases that are active at low temperature, psychrotolerant bacteria were isolated from 6 different sites in an Arctic Island (Ny-Alsund, Spitsbergen: 79°N, 12°E). Tundra soil, marine sediment and algal samples were inoculated on 3M Petri-film in situ, moved to laboratory under the cold condition with icebox, and incubated at 4℃. Isolates were transferred on 10% Skim-milk agar plates and cultured for 2 weeks at 4℃. Colonies forming clear zone were selected, and phylogenetic analysis of 16S rDNA was performed. Total 58 protease-producing strains were isolated. Among them, 47 strains were overlapped and 11 strains were finally identified: 4 strains of Pseudomonas species, 4 strains of Arthrobacter species, an Achromobacter species, a Flavobactor species, and a Flexibacter species.