Table 1. Structurally characterized AdoMet-dependent MTases.

Enzyme	Source organism	Target atom	Enzyme E.C. no.	PDB	Reference
DNA MTases
M.HhaI	Haemophilus haemolyticus	Cytosine-C5	2.1.1.73	2hmy	91
M.HaeIII	Haemophilus aegyptius	Cytosine-C5	2.1.1.73	1dct	64
M.PvuII	Proteus vulgaris	Cytosine-N4	2.1.1.113	1boo	43
M.DpnII	Streptococcus pneumoniae	Adenine-N6	2.1.1.72	2dpm	46
M.RsrI	Rhodobacter sphaeroides	Adenine-N6	2.1.1.72	1eg2	44
M.TaqI	Thermus aquaticus	Adenine-N6	2.1.2.72	2adm	97,119
DNMT2	Human	Cytosine-C5 (?)	2.1.1.37 (?)	1g55	120
Protein MTases
CheR	Salmonella typhimurium	Glutamate-O	2.1.1.80	1af7,1bc5	121,122
PRMT3	Rat	Arginine-N	2.1.1.125	1f3l	25
Hmt1	Saccharomyces cerevisiae	Arginine-N	2.1.1.125	1g6q	38
PIMT	Thermus maritima	Isoaspartate-O	2.1.1.77	1dl5	26
RNA MTases
VP39	Vaccinia orthopox virus	mRNA nucleoside-2′-O	2.1.1.57	1v39	123–126
ErmAM	S.pneumoniae	rRNA adenine-N6	2.1.1.48	1yub	127
ErmC′	Bacillus subtilis	rRNA adenine-N6	2.1.1.48	2erc	128,129
Fibrillarin homolog	M.jannaschii	rRNA nucleoside-2′-O (?)	2.1.1.66 (?)	1fbn	29
FTSJ	E.coli	RNA	2.1.1.?	1eiz,1ej0	130
Small molecule MTases
COMT	Rat	Catechol-O	2.1.1.6	1vid	131
GNMT	Rat	Glycine-N	2.1.1.20	1xva,1d2c	132,133
ChOMT	Medicago sativa L	Chalcone-O	2.1.1.?	1fpq, 1fp1	134
IOMT	Medicago sativa L	Isoflavone-O	2.1.1.?	1fpx, 1fp2	134
Other MTases
Mj0882	M.jannaschii	?	?	1dus	31
HI0319	H.influenzae	Small molecule (?)	?	1im8	32
HI0766	H.influenzae	tRNA (?)	2.1.1.34 (?)	1j85	32