ISOLATION AND PROPERTIES OF THE SITE-SPEC IFIC ENDONUCLEASE BSPTS514IFROM THERMOPHILIC BACTERIUM BACILLUS SPECIES TS514

New site-specific endonucleases BspBS31I, BstBS32I, BspIS4I, BstTS5I, BspTS514I were isolated from five thermophilic soil bacteria Bacillus sp. BS31, B. stearothermophilus BS32, Bacillus sp. IS4, B. stearotherm ophilus TS5, Bacillus sp. TS514. The enzymes are isoshizomers of the r estriction endonuclease BbvII. Endonuclease BspTS514I was obtained pur e from interfering contaminations by two consecutive chromatographies on blue agarose and hydroxyapatite. The enzyme exhibits a maximal acti vity at 55-degrees-C in 10 mM tris-HCl (pH 9,2), 10 mM MgCl2 and 50 mM NaCl.