Thermophilic Strain Bacillus species AA Contains Several Site-Specific Endonucleases

D. T. Alzhanov¹, D. V. Alzhanova¹, L. A. Zheleznaya², and N. I. Matvienko^1*

¹Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, 142292 Russia; fax: (095) 924-0493; E-mail: nikmatv@sun.ipr.serpukhov.su

²Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, 142292 Russia; fax: (095) 135-6219

^* To whom correspondence should be addressed.

Received August 19, 1997; Revision received October 20, 1997

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Thermophilic strain Bacillus species AA contains several site-specific endonucleases and three of them have been identified. BspAAI recognizes the sequence 5´-C^vTCGAG-3´ and cleaves it after the first "C" forming 4-nucleotide 5´-ends and is an isoschizomer of XhoI. BspAAII recognizes the sequence 5´-T^vCTAGA-3´ and cleaves it after the first "T" forming 4-nucleotide 5´-ends and is an isoschizomer of XbaI. BspAAIII recognizes the sequence 5´-GGATCC-3´ and is an isomer of BamHI. The optimal temperature and pH values are 42-48°C and 7.0-8.0, respectively.

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KEY WORDS: site-specific endonuclease, isoschizomer

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