2.1.1.11	S-adenosyl-L-methionine + magnesium protoporphyrin IX = S-adenosyl-L-homocysteine + magnesium protoporphyrin IX 13-methyl ester	ping-pong mechanism	
2.1.1.11	S-adenosyl-L-methionine + magnesium protoporphyrin IX = S-adenosyl-L-homocysteine + magnesium protoporphyrin IX 13-methyl ester	random bi-bi mechanism with 2 dead-end ternary complexes	
2.1.1.11	S-adenosyl-L-methionine + magnesium protoporphyrin IX = S-adenosyl-L-homocysteine + magnesium protoporphyrin IX 13-methyl ester	equilibrium-ordered bi bi mechanism	
2.1.1.11	S-adenosyl-L-methionine + magnesium protoporphyrin IX = S-adenosyl-L-homocysteine + magnesium protoporphyrin IX 13-methyl ester	ternary complex is likely to be formed either by a random or ordered addition of substrates