Catalyzes the methylation of 5-carboxymethyl uridine to 5-methylcarboxymethyl uridine at the wobble position of the anticodon loop in tRNA via its methyltransferase domain. Catalyzes the last step in the formation of 5-methylcarboxymethyl uridine at the wobble position of the anticodon loop in target tRNA. Has a preference for tRNA(Arg) and tRNA(Glu), and does not bind tRNA(Lys). Binds tRNA and catalyzes the iron and alpha-ketoglutarate dependent hydroxylation of 5-methylcarboxymethyl uridine at the wobble position of the anticodon loop in tRNA via its dioxygenase domain, giving rise to 5-(S)-methoxycarbonylhydroxymethyluridine; has a preference for tRNA(Gly). Required for normal survival after DNA damage. May inhibit apoptosis and promote cell survival and angiogenesis (By similarity). carboxymethyluridine(34) in tRNA + S-adenosyl-L-methionine = 5-(2-methoxy-2-oxoethyl)uridine(34) in tRNA + S-adenosyl-L-homocysteine Binds 1 Fe(2+) ion per subunit. Predominantly cytoplasmic. Belongs to the alkB family. Extended N-terminus.