Keywords: Cysteine-and-serine-stereochemistry-compared-2D-skeletal.png R and S configurations enantiomers of cysteine and serine Structure drawn in http //www cambridgesoft com/software/details/ ds 2 dsv 73 ChemDraw Ultra 11 0 Own 2009-05-25 Ben Mills Benjah-bmm27 Images by Ben Mills Amino acids |