Nickase and a Protein Encoded by an Open Reading Frame Downstream from the Nickase BspD6I Gene Form a Restriction Endonuclease Complex

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A. K. Yunusova¹, E. A. Rogulin¹, R. I. Artyukh¹, L. A. Zheleznaya¹, and N. I. Matvienko^2*

¹Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; fax: (4967) 790-553

²Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; fax: (495) 924-0493; E-mail: nikmatv@vega.protres.ru

^* To whom correspondence should be addressed.

Received January 30, 2006; Revision received March 29, 2006

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We are the first to have isolated a protein (186 amino acid residues) encoded by the open reading frame adjacent to the end of the BspD6I nickase (N.BspD6I) gene. Cleavage of both DNA strands near the sequence recognized by nickase (5´-GAGTC/5´-GACTC) occurs when this protein is added to the reaction mixture containing N.BspD6I. The protein encoded by the open reading frame and the nickase are suggested to be subunits of heterodimeric restriction endonuclease R.BspD6I.

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KEY WORDS: restriction-modification system, restriction endonuclease, site-specific DNA nickase, heterodimeric restriction endonuclease

DOI: 10.1134/S0006297906070157

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