Non‐destructive Detection of Methionine Sulfoxide in the Resilium of a Surf Clam by Solid‐state 13C‐NMR Spectroscopy

Abstract
Methionine sulfoxide was detected in the resilium (internal hinge ligament) of a surf clam by high‐resolution solid‐state 13C‐NMR spectroscopy involving cross‐polarization and magic angle spinning, using no chemical procedure. The results support the previous report [Kikuchi, Y. and Tamiya, N. (1981) J. Biochem. (Tokyo) 89, 1975‐1976] on a high content of methionine sulfoxide observed by chemical methods in the resilium protein of surf clam species.