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9.2: Amino acid R groups have distinct chemistries

  • Page ID
    17545
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    Each of the 20 amino acids commonly found in proteins has an R (reactive) group with its own distinctive chemistry. R groups differ in their size, polarity, charge and bonding potentials. When thinking about evolutionary changes in proteins, it is helpful to group the amino acids by their chemistry in a Venn diagram, shown on the opposite page. In general, replacing one amino acid with a second amino acid from the same sector can be considered a conservative change. The size of an R group is also important. Substitution of a large R group for a small one can significantly alter the function of a protein.


    This page titled 9.2: Amino acid R groups have distinct chemistries is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Clare M. O’Connor.

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