RESUMO
Through a series of elegant fluorescence measurements, particularly through stopped-flow kinetic measurements, it was recently demonstrated that aminoglycoside antibiotics are able to bind to the HIV-1 Rev responsive element (RRE) RNA construct in more than a 1:1 stoichiometry (Lacourciere, K. A.; Stivers, J. T.; Marino, J. P. Biocheminstry 2000, 39, 5630). Here, we present the binding study results of dimeric neomycin ligands through fluorescence anisotropy studies, to the HIV-1 RRE RNA construct. The dimeric neomycin molecules are observed to be able to bind the HIV-1 RRE RNA construct approximately 17-fold higher when compared to the monomeric neomycin, lending evidence that there are indeed two or more neomycin binding sites within the HIV-1 RRE construct.
Assuntos
Antibacterianos/farmacologia , HIV-1/efeitos dos fármacos , RNA Viral/biossíntese , Elementos de Resposta/efeitos dos fármacos , Elementos de Resposta/genética , Antibacterianos/síntese química , Sítios de Ligação/efeitos dos fármacos , Sequência de Carboidratos , HIV-1/genética , Modelos Moleculares , Dados de Sequência Molecular , Neomicina/análogos & derivados , Neomicina/metabolismo , RNA Viral/efeitos dos fármacos , RNA Viral/genética , Espectrometria de FluorescênciaRESUMO
The ability of RNA structures to adopt diverse yet complex tertiary structures has resulted in numerous fascinating RNA-protein recognition events. It was recently reported that a close relative of the HIV Rev peptide, namely a 17 residue Tat peptide from bovine immuno-deficiency virus (BIV), is able to bind to the 28 nucleotide BIV TAR RNA construct. Here we report that by simply converting the 17 residue beta-ribbon peptide structure to a 19 residue cyclopeptide, the binding affinity (Kd) of the resulting cyclopeptide to the TAR RNA target, observed by fluorescence binding study, was enhanced approximately 5-fold.
