Determination of Structurally Conservative Amino Acids of the HIV-1 Protein gp120 V3 Loop as Promising Targets for Drug Design by Protein Engineering Approaches

---

A. M. Andrianov^1* and V. G. Veresov²

¹Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, ul. Kuprevicha 5/2, 220141 Minsk, Belarus; E-mail: andrianov@iboch.bas-net.by

²Institute of Biophysics and Cell Engineering, National Academy of Sciences of Belarus, ul. Akademicheskaya 27, 220072 Minsk, Belarus; E-mail: veres@biobel.bas-net.by

^* To whom correspondence should be addressed.

Received January 31, 2006; Revision received March 20, 2006

---

Based on the published NMR spectroscopy data, three-dimensional structures of the HIV-1 gp120 protein V3 loop were obtained by computer modeling in the viral strains HIV-Haiti and HIV-MN. In both cases, the secondary structure elements and conformations of irregular stretches were determined for the fragment representing the principal antigenic determinant of the virus, as well as determinants of the cellular tropism and syncytium formation. Notwithstanding the high variability of the amino acid sequence of gp120 protein, more than 50% of the V3 loop residues retained their conformations in the different HIV-1 virions. The combined analysis of the findings and the literature data on the biological activity of the individual residues of the HIV-1 V3 loop resulted in identification of its structurally conservative amino acids, which seem to be promising targets for antiviral drug design by protein engineering approaches.

---

KEY WORDS: human immunodeficiency virus type 1, protein gp120, V3 loop, spatial structure, computer modeling, drugs

DOI: 10.1134/S000629790608013X

---