Properties TableAll Structures
AlaCysAspGluPheGlyHisIleLysLeu
MetAsnProGlnArgSerThrValTrpTyr
Atomic naming in PDB consists of 4 character field: atomic symbol (2 char), remoteness indicator (1 char), branch designator (1 char).
Remoteness indcator uses Greek letter distance abbreviation. In order of increasing distance, these are A for alpha, B for beta, G for gamma, D for delta, E for epsilon, Z for zeta, and H for eta.
Branch designator: digit designating the branch direction; left blank if the sidechain is unbranched.
Color scheme: Red=Oxygen; Gray=Carbon; Blue=Nitrogen; Cyan=Hydrogen; Yellow=Sulphur

Cysteine


AAC
CodeCys
FullnameCysteine
Side chain type"hydrophobic (Nagano, 1999)"
Mass121.16
pI5.05
pK1(a-COOH)1.92
pK2(a-+NH3)10.7
pKr (R)8.37
hydrophobicX
positive-
negative-
polar-
charged-
smallX
tiny-
aromatic-
aliphatic-
van der Waals volume86
Remarks "Under oxidizing conditions, two cysteines can join together by a disulfide bond to form the amino acid cystine. When cysteines are part of a protein, insulin for example, this enforces tertiary structure."