ISSN:
1573-4943
Keywords:
conformational energy
;
three-dimensional structure
;
amino acid substitution
;
P21 proteins
;
transformation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The conformational effects of different amino acid substitutions for Gly at position 12 in theras-oncogene-encoded P21 proteins have been investigated using conformational energy calculations. Mutations that cause amino acid substitutions for Gly 12 result in a protein that produces malignant transformation of cells. It had previously been shown that substitution of Val, Lys, or Ser for Gly at position 12 results in a major conformational change, and that the preferred lowest energy structure for each of the substituted peptides is identical. It is now found that substitution for Gly 12 of other amino acids that have widely disparate helix-nucleating potentials and completely different side chains (Asp, Asn, Cys, Phe, Tle, Leu, and Ala) all produce this identical lowest energy conformation. This finding is consistent with the recent results of site-specific mutagenesis experiments showing that P21 proteins containing these amino acids at position 12 all promote malignant transformation of cells and suggests the existence of a “malignancy-causing” conformation for the P21 proteins.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01025176
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