Abstract
Since the discovery of HindII, more than 120 kinds of site-specific endodeoxyribonucleases (restriction enzymes) have been isolated from some 600 species of bacteria and reported. All of them have been obtained from terrestrial bacteria except FokI isolated from a marine bacterium, Flavobacterium okeanokoites . Furthermore, the marine bacteria have not been as extensively studied as the terrestrial bacteria. Under these circumstances, the authors have been attempting to survey site-specific endonucleases in the marine bacteria of the laboratory collection of the Ocean Research Institute, University of Tokyo. Two out of 68 preparations, i.e., those from Flavobacterium I 16-04 and I 16-11, showed appreciable restriction endonuclease-like activities. The authors tried to purify the enzyme from Flavobacterium I 16-04.