1 M0H S-(hydroxymethyl)-L-cysteine 1.000 2 QCS S-carbamoyl-L-cysteine 0.900 3 SCY S-acetyl-cysteine 0.900 4 060 S-methyl-D-cysteine 0.889 5 SMC S-methylcysteine 0.889 6 6KM S-propanoyl-L-cysteine 0.818 7 ECX S-ethyl-L-cysteine 0.800 8 XCN S-cyano-L-cysteine 0.800 9 A8C 3-(methylsulfanyl)propanoic acid 0.778 10 BB9 (2z)-2-amino-3-sulfanylprop-2-enoic acid 0.778 11 CYS Cysteine 0.778 12 DCY D-cysteine 0.778 13 C3Y S-[(1s)-1-hydroxy-1-(hydroxyamino)ethyl]-L-cysteine 0.750 14 CGV S-[(R)-carboxy(hydroxy)methyl]-L-cysteine 0.750 15 CY4 S-butyryl-cystein 0.750 16 CYW S-[(2r)-2-hydroxypropanoyl]-L-cysteine 0.750 17 I3L Allyl-cysteine 0.727 18 OCY Hydroxyethylcysteine 0.727 19 SLZ L-thialysine 0.727 20 SWW (2~{S})-2-azanyl-3-(2-hydroxyethylsulfanyl)propanoic acid 0.727 21 03Y 2-methyl-L-cysteine 0.700 22 BB6 (2z)-2-amino-3-sulfanylbut-2-enoic acid 0.700 23 CG6 Beta-methyl-cysteine 0.700 24 CSB Cys bound to lead ion 0.700 25 CSO S-hydroxycysteine 0.700 26 CSS S-mercaptocysteine 0.700 27 CSX S-oxy cysteine 0.700 28 CSZ S-selanyl cysteine 0.700 29 DEI (2z)-2-hydroxy-3-(methylsulfanyl)prop-2-enoic acid 0.700 30 DQY 3-(dimethyl-lambda~4~-sulfanyl)propanoic acid 0.700