Shows aminotransferase activity with methionine and histidine as substrates, and to a lesser extent also with phenylalanine. a 2-oxocarboxylate + L-methionine = 4-methylsulfanyl-2-oxobutanoate + an L-alpha-amino acid Homodimer. Belongs to the class-I pyridoxal-phosphate-dependent aminotransferase family.