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Aims: Molecular insights into the analyte-bioreceptor interactions play a vital role in the efficacy of designing biosensors. Biosensors that utilize aptamers as bioreceptors are highly efficient with high specificity and reusability. Aptasensors can be used in a variety of conditions of in vivo or in vitro. The aim of this study was to study the changes in the solvent conditions of the binding of MUC1-G peptide and the anti-MUC1 aptamer.
Materials and Methods: The molecular dynamics simulation method has been used to investigate the change of molecular interactions due to selective variations in solvent conditions. The results can be used to reflect a variety of environments, in which the aptasensor utilizes anti-MUC1 S2.2 aptamer as a bioreceptor and MUC1–G peptide as a biomarker.
Findings: Based on the calculated binding energies, the medium containing 0.10M NaCl and anti-MUC1 S2.2 aptamer demonstrates the highest affinity toward the MUC1-G peptide among the studied concentrations of NaCl, and the arginine amino acid has a key role in the aptamer–peptide binding. Conclusion: The results of MD simulation indicated that the increase in the concentration of NaCl in the interaction environment leads to a decrease in binding energies; therefore, the binding affinity of the anti-MUC1 aptamer to MUC1-G peptide decreases. Insights from present modeling demonstrate the selectiveness and sensitivity to solvent conditions, which should be considered in the development of biosensors.

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The effect of tillage (conventional and zero tillage), crop establishment (raised-bed and flat-bed), and weed management practices (herbicide alone and integrated approach) was studied on productivity, profitability, nutrient uptake and physico-chemical properties of soil in soybean–wheat cropping system, at New Delhi during 2010–2012. Sixteen treatment combinations consisting of four tillage and crop establishment practices, viz. Conventional Tillage–raised-bed (CT–bed), CT–flat-bed, Zero Tillage–raised-bed (ZT–bed) and ZT–flat-bed; and four weed management practices, viz. unweeded control, herbicide+Hand Weeding (HW), herbicide combination, and crop residue + herbicide were laid out in a split-plot design. Soybean produced higher seed yield (+7.6%) under raised-bed and wheat under flat-bed (+6.2%), but the system productivity was highest under CT–flat-bed. Pre-emergence application of pendimethalin followed by HW gave higher yield of soybean, while all weed control treatments were found equally good for wheat. Conventional tillage resulted in higher uptake by soybean of N (+5.0%), P (+4.4%) and K (+3.1%) than ZT, particularly under raised-bed conditions. In wheat, CT and ZT resulted in almost similar nutrient uptake under flat-bed. Total nutrient uptake of the system was similar for N and P under all tillage and crop establishment practices, while herbicide+HW gave 4.9–7.2% higher uptake than herbicide combination or crop residue+herbicide. Net benefit: cost ratio of the system was the highest (> 2.0) under ZT–flat-bed and herbicide combination. There was beneficial effect on physico-chemical properties of soil under ZT and residue application, but it is necessary to run the experiment in long-term to see the cumulative effect over time.