Chitinase-producing marine bacteria from Cheju Island

Abstract

Chitinase-producing marine bacteria were isolated, chitinase activity of selected bacteria was measured, and chitinase genes were cloned from the bacteria. Seawater and sediment isolated from coastal area of Cheju Island, Korea were diluted in sterile seawater and spread on the selective medium containing colloidal chitin. Total 9 strains of clear-hole formation bacteria were selected as the chitinase producer. Taxonomic identification was performed using phylogenetic analysis of 16S rDNA: Vibrio sp. CJ11027, Bacillus sp. CJ11043, Hongella chejuensis gen. et. sp. nov. CJ11049, Kordia chejuensis gen. et. sp. nov. CJ11052, Kordia chejuensis gen. et. sp. nov. CJ 11064, Thalassospira chejuensis sp. nov. CJ11073, Microbulbifer chejuensis sp. nov. CJ11075, Bacillus sp. CJ11076, Cellulomonas sp. CJ10597. Chitinase activity of these bacteria was measured by detecting the amount of ρ-nitrophenol released from ρ-nitrophenyl β-D-N-acetylglucosaminide (PNG). The selected bacteria showed more than 1.00 (U/mg) of specific chitinase activity. Especially, Vibrio sp. CJ11027, Hongella chejuensis gen. et. sp. nov. CJ11049, Thalassospira chejuensis sp. nov. CJ11073 showed high chitinase activity. Partial sequences of chitinase genes were isolated from Vibrio sp. CJ11027, Kordia chejuensis gen. et. sp. nov. CJ11052, Kordia chejuensis gen. et. sp. nov. CJ 11064, Microbulbifer chejuensis sp. nov. CJ11075, and Bacillus sp. CJ11076.