The majority of inactivating mutations of p53 reside in the central core
DNA binding domain of the
protein. In this computational study, we investigated the structural effects of a novel p53 mutation (G389E), identified in a patient with
congenital adrenal hyperplasia, which is located within the extreme C-terminal domain (CTD) of p53, an unstructured, flexible region (residues 367-393) of major importance for the regulation of the
protein. Based on the three-dimensional structure of a carboxyl-terminal
peptide of p53 in complex with the S100B
protein, which is involved in regulation of the
tumor suppressor activity, a model of wild type (WT) and mutant extreme CTD was developed by molecular modeling and molecular dynamics simulation. It was found that the G389E
amino acid replacement has negligible effects on free p53 in
solution whereas it significantly affects the interactions of p53 with the S100B
protein. The results suggest that the observed mutation may interfere with p53 transcription activation and provide useful information for site-directed mutagenesis experiments.