WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY 10: (1) 30-32 JAN 1994

ISOLATION AND CHARACTERIZATION OF RESTRICTION-ENDONUCLEASE EC HKI FROM AN ENTEROBACTER-CLOACAE STRAIN

CHAN HY, CHAN YC, KAM KM, SHAW PC

Department of Biochemistry, CUHK

An Enterobacter cloacae strain, producing restriction enzyme Ec/HKI, was isolated from a decaying potato. The enzyme is an isoschizomer of Eam1105I, which recognizes and cleaves GACNNN!NGTC. Ec/HKI was produced at high activity (4 X 10(4) U/g wet cells) and was purified from contaminants which interfere with restriction digestion by passing the cell lysate through DEAE-Sephacel and heparin columns. Activity was optimal at 37-degrees-C in a medium salt buffer.