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Updated: Jun 24, 2026
12:07
Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
Published on: November 22, 2014
M1.MboII and M2.MboII type IIS methyltransferases: different specificities, the same target
Beata Furmanek-Blaszk1, Robert Boratynski1, Natalia Zolcinska1
1Department of Microbiology, University of Gdansk, 80-822 Gdansk, Kladki 24, Poland.
Microbiology (Reading, England)
|April 1, 2009
Summary
The MboII restriction-modification system uses two methyltransferases to protect bacterial DNA. M2.MboII methylates cytosine in single-stranded DNA, and the complete system is stable and harmless to bacteria.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Restriction-modification (R-M) systems protect bacterial DNA from foreign DNA.
- The MboII R-M system from Moraxella bovis recognizes an asymmetrical DNA sequence.
Purpose of the Study:
- To characterize the MboII restriction-modification system, focusing on the M2.MboII methyltransferase.
- To understand the mechanism and properties of M2.MboII activity.
Main Methods:
- Cloning and purification of M2.MboII methyltransferase.
- Biochemical assays to determine methylation activity and substrate specificity.
- Analysis of the complete MboII R-M system's stability and effect on bacterial cells.
Main Results:
- M2.MboII methylates the internal cytosine in the 3'-CTTCT-5' recognition sequence to N(4)-methylcytosine.
- M2.MboII can methylate single-stranded DNA.
- Divalent cations inhibit M2.MboII activity, similar to M2.NcuI.
- The complete MboII R-M system is stable and well-tolerated by bacterial cells.
Conclusions:
- M2.MboII is a novel methyltransferase with unique substrate specificity, including single-stranded DNA.
- The MboII R-M system offers a stable and non-harmful DNA protection mechanism for bacteria.
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