Isolation and identification of protease-producing marine bacteria from Shanghai Lingang sea area

170 marine bacterial strains were isolated from marine samples including seawater and sediment of Lingang sea area, Shanghai.The high protease-producing strain SE2011 was obtained by testing proteolysis zone in casein plates and Folin- phenol assay. Based on morphological characteristics, physiological and biochemical identification, 16S rDNA sequence and phylogenetic analysis, the isolate SE2011 was classified as Listonella anguillarum.Growth characteristics indicated that this strain growed well from 15℃ to 30℃, the optimum growth temperature was 30℃.And it maintained its growth ranging from 0 to 7% ( W/V) NaCl, the best salinity of growth was 1% ( W/V) NaCl. Enzymatic properties indicated that this protease showed activity from 30℃ to 90℃, the optimum was at 55℃.The optimum pH for the enzyme was 8.0 which proved it to be alkaline protese and it had activity over a broad range of pH6.0～10.0.