Whole Genome Shuffling to Enhance Activity of Fibrinolytic Enzyme-producing Strains / 中国生物工程杂志

ABSTRACT

DC-12 is a Bacillus strain with strong fibrinolytic activity was screened from Douchi.A novel breeding technology——whole genome shuffling was applied to enhance the production of fibrinolytic enzyme.First of all,a candidate mutant library was constructed by treating DC-12 with ultraviolet rays andhNO2,respectively.Based on studying the optimum conditions for protoplast preparation and regeneration of DC-12,multi-parental whole genome shuffling with 4 strains was conceded by protoplasts electrical fusion,then combines with the screening method of double-inactive protoplast,two strains withhigher yield of fibrinolytic enzyme were obtained effectively,which can descend stably after five generations,and their enzyme production reached 2710 IU/ml,which was increased by 4~5 fold compared with the mutants,respectively.