چکیده
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The interactions of nanoparticles with single stranded nucleic acids (NAs) have important
implications ranged from drug and gene delivery to nano-machine building to bio-sensor design
and productions [1] . Therefore, in this research work, we investigate the interactions of a gold
nanosheet as drug carrier with RNA aptamer as anti-HIV drug acting as inhibitor for HIV-1
protease by molecular dynamics simulation method.
All molecular dynamics simulations were performed using the NAMD-2.12 software [2]
and the visualizations and analyzing of MD trajectories were executed by VMD-1.9.2 package
[3]
. Three sequences families of RNA aptamers were selected. Recently, [4] studied these aptamers
experimentally and reported anti-HIV properties for them. The Second-generation RNA
aptamers were selected from Kinefolde web server. The third structures predicted by SIMRNA
web server are in agreement with the experimental data.
The interactions between GNP and considered aptamers have been studied by extracting
the structural and energetics results from the simulation trajectories. The structural data are like
RMSD, hydrogen bonds and center of mass distances were used for elucidation of the adsorption
and immobilization of aptamer on the gold nanosheets as well as its native folded structue.
Enetrgerics of the interactions such as total inteaction energy and the contribution of van der
Waals and electrostatic interactions in total energy were used for estimation of the adsorption
strength of studied aptamers in the binded fashion. These results could give insights into the
flexibility of aptamer sequences the qualitative information about the conformational changes of
the aptamer’s backbone along the simulation time. These values were in a reasonable range and
indicated the native structure of aptamer remained along the simulation. The intraction residues
were verifed by the help of the averaged RMSF values for intraction and nonintraction aptamers
accompanying conventional visual
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