Ball & stick model of L-cysteine (C).







Some facts on L-cysteine.

1. Abbreviation: Cys.
2. One-letter code: C.
3. Molecular mass: 121 daltons.
4. Side-chain (or R-group) features:
   • Formula: -CH₂-SH;
   • Category: Slightly hydrophobic;
   • pK_a: 9.3.
     (to produce the -S^- anion)

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Ball & Stick model of L-serine (S)
Back to Question 4.








Some facts on L-serine.

1. Abbreviation: Ser.
2. One-letter code: S.
3. Molecular mass: 105 daltons.
4. Side-chain (or R-group) features:
   • Formula: -CH₂-OH;
   • Category: Hydrophilic;
   • pK_a: none.

Return to image of Ser.

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Last modified August 1, 1996