A Site-Specific Endonuclease from Thermophilic Strain Bacillus species ZE Is a ClaI Isoschizomer

E. N. Zheleznyakova¹, L. A. Zheleznaya², I. V. Svad'bina², 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 February 26, 1998

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Strain Bacillus species ZE with a maximal yield of the ClaI isoschizomer was chosen from 12 natural thermophilic strains producing ClaI isomers. The yield is 110 times higher than that of the ClaI prototype endonuclease from Caryophanon latum L. The enzyme is sensitive to DNA dam-methylation and is highly stable under storage.

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KEY WORDS: site-specific endonuclease, restriction-modification, DNA methylation

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