Reaction catalyzed by peptide-methionine (S)-S-oxide reductase (1.8.4.11), peptide-methionine (R)-S-oxide reductase (1.8.4.12)

		+			=			+
	N-acetyl-L-methionine (R,S)-sulfoxide	+		thioredoxin	=		N-acetyl-L-methionine	+		thioredoxin disulfide