4TS2|1|Y|38E|104 38E 4TS2|1|Y|SUC|103 SUC 4TS2|1|X|K|102 K ion 4TS2|1|Y|K|102 K ion 4TS2|1|X|K|103 K ion 4TS2|1|X|MG|101 MG ion 4TS2|1|Y|CCC|101 CCC rna