FIELD: genetic engineering. SUBSTANCE: restrictase Eco 29KI is isoschizomer of restrictase SacII. The new recombinant plasmid pECO 29KI (size is 6.6 thousand nucleotide pairs) is obtained and it has the genes of restriction-modification system Eco 29KI, consists of ClaI-fragment od DNA-vector PUC 129 and two ClaI-fragments of the natural plasmid p29k, has also four recognition sizes by restrictase HindIII, three recognition sites of restrictase, two sites for XhoI, and one site for restrictases: SalI, BglII, Bam HI, resistance dominant to ampicillin. Obtained plasmid provides the increased synthesis of restrictase Eco 29KI. Proposed strain of Escherichia coli BKM CR-369D prepared by transformation of plasmid DNA pECO 29KI into the strain E. coli Z85 provides high level of enzyme content, 100000000 U/1 g wet biomass. The yield of purified enzyme is 500000 U/g biomass. EFFECT: increased yield of enzyme. 3 cl
Authors
Dates
1996-02-10—Published
1992-07-30—Filed