Location of the Bases Modified by M.BcoKIA and M.BcoKIB Methylases in the Sequence 5´-CTCTTC-3´/5´-GAAGAG-3´

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I. V. Svadbina^1*, N. N. Matvienko², L. A. Zheleznaya¹, and N. I. Matvienko²

¹Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; fax: 8 (27) 33-0553; E-mail: irina@iteb.ru

²Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; fax: (7-095) 924-0493

^* To whom correspondence should be addressed.

Received November 16, 2004; Revision received December 10, 2004

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The strain Bacillus coagulans K contains two DNA-methyltransferases, M.BcoKIA and M.BcoKIB, which recognize the sequence 5´-CTCTTC-3´/5´-GAAGAG-3´ and possess N4-methylcytosine and N6-methyladenine specificities, respectively. A special construct containing the recognition site of BcoKI and sites of four IIS restriction endonucleases (IIS restriction endonuclease cassette) was designed to locate the nucleotides modified by the methylases. The modified bases were determined as: 5´-m⁴CTCTTC-3´/5´-GAAGAm⁶G-3´.

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KEY WORDS: M.BcoKIA, M.BcoKIB, DNA-methyltransferase, IIS restriction endonuclease

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