L-methionine(2S)-2-amino-4-(methylsulfanyl)butanoic acid(S)-2-amino-4-(methylthio)butanoic acid(S)-2-amino-4-(methylthio)butyric acid(S)-methionineL-(-)-methionineL-MethioninL-MethionineL-alpha-amino-gamma-methylmercaptobutyric acidMMETHIONINEMetMethionine