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Krishnamoorthy, J.

Publications and source records attributed to Krishnamoorthy, J..

3 recordsLinked to original sources

Network analysis of chromophore binding site in LOV domain

Photoreceptor proteins are versatile toolbox for developing biosensors for optogenetic applications. These molecular tools get activated upon illumination of blue light, which in turn offers a non-invasive method for gaining high spatiotemporal resolution and precise control of cellular signal transduction. The Light-Oxygen-Voltage (LOV) domain family of proteins is a well-recognized system for constructing optogenetic devices. Translation of these proteins into efficient cellular sensors is possible by tuning their photochemistry lifetime. However, the bottleneck is the need for more understanding of the relationship between the protein environment and photocycle kinetics. Significantly, the effect of the local environment also modulates the electronic structure of chromophore, which perturbs the electrostatic and hydrophobic interaction within the binding site. This work highlights the critical factors hidden in the protein networks, linking with their experimental photocycle kinetics. It presents an opportunity to quantitatively examine the alternation in chromophores equilibrium geometry and identify details which have substantial implications in designing synthetic LOV constructs with desirable photocycle efficiency.

bioengineering↗

ITC and SPR Analysis Using Dynamic Approach

Biophysical techniques such as Isothermal Calorimetry (ITC) and Surface Plasmon Resonance (SPR) are routinely used to ascertain the global binding mechanisms of protein-protein or protein-ligand interaction. Recently, Dumas etal, have explicitly modelled the instrument response of the ligand dilution and analysed the ITC thermogram to obtain kinetic rate constants. Adopting a similar approach, we have integrated the dynamic instrument response with the binding mechanism to simulate the ITC profiles of equivalent and independent binding sites, equivalent and sequential binding sites and aggregating systems. The results were benchmarked against the standard commercial software Origin-ITC. Further, the experimental ITC chromatograms of 2-CMP + RNASE and BH3I-1 + hBCLXL interactions were analysed and shown to be comparable with that of the conventional analysis. Dynamic approach was applied to simulate the SPR profiles of a two-state model, and could reproduce the experimental profile accurately.

biophysics↗

Log D Analysis using Dynamic approach

Log D is one of the important parameters used in Lipinskis rule to assess the druggability of a molecule in pharmaceutical formulations. It represents the logarithm (log10) of the distribution coefficient (D) of a molecule. The distribution coefficient is defined as the ratio of the concentration of the sum of ionized and unionized species of a molecule distributed between a hydrophobic organic phase and an aqueous buffer phase. Since the pH affects the ionic state of a molecule, log D value (which is dependent on the concentrations of the ionized species) also becomes dependent on pH. In this work, the conventional algebraic method is compared with a more generalized dynamic approach to model the distribution coefficient of amphoteric, diamino-monoprotic molecule and monoprotic acid in the presence of salt or co-solvent. Recently reported experimental log D data of amphoteric molecules such as nalidixic acid, mebendazole, benazepril and telmisartan, were analyzed using both these approaches to show their equivalence.\n\nGRAPHICAL ABSTRACT\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC=\"FIGDIR/small/259770_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (17K):\norg.highwire.dtl.DTLVardef@17c4988org.highwire.dtl.DTLVardef@bf859corg.highwire.dtl.DTLVardef@1dccb4dorg.highwire.dtl.DTLVardef@a766a1_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗