The study on selection for strain from F. yellowsea YS 9412 130 producing low temperature alkaline protease after complex mutagenesis of protoplasts

Taking the mutant F. yellowsea YS 9412 130 SW 1 104 as the initial strain, under the optimum conditions of the formation and regeneration,protoplasts of the strain are prepared, mutagenic treatments of the protoplasts are undergone. After selecting from a large amount of the regenerative mutants and culturing in fresh water, a stable mutant SW 2 104 producing high output alkaline protease is obtained. The strain can produce a large amount of enzyme in tap water medium, enzyme activity is 3 910U/ml. It is possible for low temperature alkaline protease from F. yellowsea YS 9412 130 to solve the problem of large scale production and to break the limitation of industrial region.