label: methyl-Co(III)-[quaternary-amine-specific corrinoid protein] + N-methyl-L-proline => Co(I)-[quaternary-amine-specific corrinoid protein] + L-proline betaine + H(+)
label_lc: methyl-co(iii)-[quaternary-amine-specific corrinoid protein] + n-methyl-l-proline => co(i)-[quaternary-amine-specific corrinoid protein] + l-proline betaine + h(+)