S-adenosyl-L-methionine : protein arginine N-methyltransferase having an optimum pH around 7.2 has been purified approximately 1, 800 fold with 16 % yield from wheat germ and an attempt was made to resolve controversial multiplicity on the enzyme.
The end products of the purified enzyme preparation were NG-monomethylarginine and NG, N´G_dimethylarginine in a ratio of 70:30, and the enzyme preparation lost the ability of less purified ones to carry out the synthesis of NG, NG-dimethylarginine, strongly indicating that different enzymes were . responsible for the production of different methylated derivatives of arginine.
Contrary to our expectation, histone was better substrate than myelin basic proteins from various sources.
From the above results and products ratio change at each step of purification, we discussed the possibility that three enzymes were involved in the formation of three methylated arginine derivatives which has been identified so far.
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