ABSTRACT
Denaturation of proteins plays a crucial part in cellular activities. In this study, we have investigated the folding unfolding pathways of zebrafish dihydrofolate reductase (zDHFR) in presence of different chemical denaturants which were found to be an influential factor for the refolding yield by UV-visible spectrophotometric analysis. The activity change of zDHFR has been observed in presence of three different denaturants like Acetic Acid (AcOH), Sodium Dodecyl Sulphate (SDS), and Ethanol (C2H5OH). Spectrophotometric analysis reveals that protein unfolded completely at different concentrations and times by these denaturants. The spontaneous refolding experiments of chemically denatured zDHFR were also conducted to verify the spontaneous refolding yield. These investigations have helped us to decipher a picture about the denaturants contributing to achieving the refolding yield. We observed that acetic acid is a stronger denaturant among all, and the spontaneous refolding yields were higher from SDS denaturation. In the light of the above findings, higher spontaneous refolding yields were obtained from the low concentration of denaturants.
ABSTRACT
Abstract: A simple, rapid, accurate and economical method has been developed for thesimultaneous estimation of Emtricitabine and Tenofovir Alafenamide in tablet dosage form.The linearity of the method was found to be in the range of 10.8µg/ml- 12.8µg/ml forTenofovir Alafenamide and 86.4µg/ml-102.4µg/ml for Emtricitabine. From the developedmethod the drugs showed maximum absorbance at 263 and 281nm for Tenofovir Alafenamideand Emtricitabine respectively. The percentage purity of the drugs was found as 96.8 and97.6%w/w for Tenofovir Alafenamide and Emtricitabine respectively. The method was alsofound to be accurate, precise, robust and rugged. The limit of detection and the limit ofquantification were found to be 0.234µg/ml and 0.710µg/ml for Tenofovir Alafenamide and2.25µg/ml and 6.83µg/ml for Emtricitabine respectively..
ABSTRACT
One of the important fields in nanotechnology is the development of an environment friendly method for the synthesis of nanoparticles. Many approaches show that microorganisms are the most reliable tools for biosynthesis of nanoparticles compared to physical and chemical methods. In our study, fungi have been exploited for extracellular production of metal nanoparticles. It was observed that in Scedosporium, silver ions are reduced to silver nanoparticles, which was confirmed by UV-visible spectrophotometry and AFM. Optimization studies showed that as the concentration of AgNO3 used for synthesis increased, particles' size also increased. Size of the particles at different concentrations of AgNO3 was observed to be 79-107 nm with particles being ellipsoidal to spherical in shape. Silver nanoparticles synthesized from 2.0 mM silver nitrate, showed maximum antimicrobial activity compared to all antibiotics tested including synergistic effects. In vitro cytotoxicity of silver nanoparticles against MCF 7 and PC 3 showed that as the concentration of silver nanoparticles increased, a decrease in the percentage cell viability was observed with IC50 values being 60.09 and 57.43 µg/ml respectively. Therefore, through this study, it could be said that extracellular synthesis of silver nanoparticles from Scedosporium was simple, ecofriendly, proving excellent antimicrobial and anticancer agents.
ABSTRACT
Objective: To investigate the interaction between ciprofloxacin (CIP) and ferric-ion binding protein (FBP) from pathogenic bacteria, so as to determine whether FBP is the target of CIP. Methods: Reactions between ciprofloxacin and FBP from N. gonorrhoeae, which was expressed in E. coli, were monitored by UV-visible and NMR spectroscopy. Results: Fe3+ was removed from holo-FBP by CIP in 10 mmol/L Tris-Cl buffer, pH 7.40, at 298 K, and half of the loaded Fe3+ was taken off when 50 molar equivalence of CIP was present. Conclusion: CIP can remove Fe3+ from holo-FBP, indicating that CIP can interfere with the Fe3+ capture of the bacteria and influence the growth and virulence of the bacteria.