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Assessment of Immunologically Relevant Dynamic Tertiary Structural Features of the HIV-1 V3 Loop Crown R2 Sequence by ab initio Folding
10:50

Assessment of Immunologically Relevant Dynamic Tertiary Structural Features of the HIV-1 V3 Loop Crown R2 Sequence by ab initio Folding

Published on: September 15, 2010

The 80's loop (residues 78 to 85) is important for the differential activity of retroviral proteases

J Stebbins1, E M Towler, M G Tennant

  • 1Department of Molecular Genetics, SmithKline Beecham Pharmaceuticals, King of Prussia, PA 19406, USA.

Journal of Molecular Biology
|April 4, 1997
PubMed

The abundance of structural data available for retroviral proteases affords a unique opportunity to investigate structure activity relationships. Our approach attempts to genetically engineer an HIV (human immunodeficiency virus)-1 protease that is functionally equivalent to the HIV-2 and the SIV (simian immunodeficiency virus) enzymes and conversely to engineer an HIV-2 protease that is functionally equivalent to the HIV-1 enzyme. For this purpose, the HIV-2 and SIV proteases were cloned and characterized in an Escherichia coli (E. coli) assay system along with 33 engineered HIV-1 and HIV-2 enzymes. The results of these experiments show that a relatively large S1 or S1' subsite volume, which is likely determined by the conformation of the 80's loop (residues 78 to 85), is necessary to fully accommodate the HIV-1 protease specificity site AETF*YCDG (the asterisk indicates the location scissile bond) during productive binding.

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