Molecular and Cellular Biochemistry

, Volume 110, Issue 2, pp 103–111 | Cite as

Detection of a CpA methylase in an insect system: characterization and substrate specificity

  • Chalasani Devajyothi
  • Vani Brahmachari


A cytosine-specific DNA methyltransferase (EC has been purified to near homogeneity from a mealybug (Planococcus lilacinus). The enzyme can methylate cytosine residues in CpG sequences as well as CpA sequences. The apparent molecular weight of the enzyme was estimated as 135,000 daltons by FPLC. The enzyme exhibits a processive mode of action and a salt dependance similar to mammalian methylases. Mealybug methylase exhibits a preference for denatured DNA substrates.

Key words

DNA methylation coccids processive enzyme RNA inhibition CpI methylation 


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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • Chalasani Devajyothi
    • 1
    • 2
  • Vani Brahmachari
    • 1
    • 2
  1. 1.Department of Microbiology and Cell BiologyIndian Institute of ScienceBangaloreIndia
  2. 2.ICMR Centre for Genetics and Cell BiologyIndian Institute of ScienceBangaloreIndia

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