The GATATC-modification enzymeEcoRV is closely related to the GATC-recognizing methyltransferasesDpnII anddamfromE.coliand phage T4

Abstract

The amino acid sequence of EcoRV DNA methyltransferase which methylates the amino group of the 5′-adenine residue of the target sequence GATATC has been found to be closely related to that of three other adenine methyltransferases, DpnII, dam and damT₄, the target sequence of which is GATC. Despite large differences on the DNA level, the four sequences show four blocks of homologies. One of these blocks has the sequence DVYXDPPY and is found with little modification in numerous other DNA inethyltransferases. It is speculated that it could be the binding site of the methyl donor, S-adenosylmethionine. On the other hand, the identification of a DNA-binding region is more tenuous. As expected, no analogies with (dimeric) repressors and cro proteins which have the characteristic helix-turn-helix motif have been observed.