6UV2|1|A|BEF|502 BEF 6UV2|1|A|MG|503 MG ion 6UV2|1|A|MG|504 MG ion 6UV2|1|A|MG|505 MG ion 6UV2|1|A|MG|506 MG ion 6UV2|1|A|ADP|501 ADP rna