PTH-methionine sulfoxide elutes between Q and T using the
5%THF/acetonitrile solvent system on the PE/ABI 473A. The peak is about 1
1/2 times broader than the other PTH-amino acids which elute in this
region.
Methionine sulfoxide is apparently not completely reduced in the ABI 473A
in spite of the DTT in the sequencer reagents.
I confirmed the identity with PTH-methionine sulfoxide from Research
Organics Inc., Cleveland, Ohio, 800-321-0570.
Marjory Barnes
Novartis Pharma AG
Basel, Switzerland
marjory.barnes@pharma.novartis.com