Modeling of the 3D structure of the HIV-Haiti immunodominant epitope
Biofizika 51(1): 81-91
2006
ISSN/ISBN: 0006-3029 PMID: 16521557 Document Number: 604140
The 3D structure for the HIV-Haiti immunodominant epitope was computed in terms of NMR spectroscopy data using the theoretical procedure including a probabilistic approach in conjunction with molecular mechanics algorithms and quantum chemical methods. The immunogenic crown of the virus protein gp120 was shown to form in solution a prevalent conformation whose geometric parameters match the double beta D-turn IV-IV. Two structures observed in crystal were found in the ensemble of the best-energy conformations of the HIV-Haiti principal neutralizing epitope. From a comparison of simulated structures with those computed previously for the HIV-Thailand and HIV-MN isolates, it was concluded that the immunogenic tip of gp120 gives rise to similar spatial backbone forms in different HIV-1 strains but has some inherent conformational flexibility of its individual amino acid residues. The differences in local fragment structures revealed in three isolates of HIV-1 are supposed to be important for the specificity of its binding with neutralizing antibodies.