We researched the NIPAM/water solution by means of molecular dynamics, osmometry, densimetry and ITC-calorimetry. Employing Kirkwood-Buff inversion, we gathered improved force-field and provided consistent micro- and macroscopic insight. link
Within the collaboration with Darmstadt simulation group (prof. Nico van der Vegt) we have investigated the generic stabilizing effect of TMAO on pentaalanine and other uncharged peptides. TMAO effect at both ambient and deep-ocean conditions was studied and peptide-length and chain-termination challenges were resolved. link
Finally, we were happy to experimentally support our Santa Barbara and Darmstadt colleagues, in their review article on thermodynamic effect of TMAO and urea mixtures with implications on protein denaturation/protection. Complete Kirkwood-Buff description is available over very broad range of concentrations. link
New season of Teochem seminars is here. You can expect a high quality mixture of Czech and foreign speakers The seminars will take place on many Fridays and on few Mondays. We start on Friday, September 20 at 14.30. link
We have just published two works on combined experimental (time-resolved spectroscopy) and theory (ab-initio QM/MD) investigation of electron transfer over large distance (conjugated amino acid sequence) in Azurin.
In our recent contribution with Berlin & Freiburg colleagues, we provide a generic evidence on sufficient interaction ingredients between biomolecules and salts (effective B2-interaction and mean field electrostatics) to manifest in the direct, or reverse Hofmeister series. More details can be found in the manuscript.
Chudoba R.; Heyda J.; Dzubiella J. Tuning the collapse transition of weakly charged polymers by ion-specific screening and adsorption. Soft Matter, 2018, 14, 9631-9642
We knew that guanidinium cation is an unique species, which desire our attention. Its ability to form cation-cation pairs is manifested in aqueous solutions of guanidinium salts as well as between arginine sidechains in proteins. Such arginine magic was pointed out to lead to an unexpected attraction between polyarginine chains with consequences to the action of arginine-rich cell penetrating peptides.
Junior independent researcher, Kuhan Chandru, formerly at Earth-Life Science Institute, Tokyo, extended our group. Kuhan is experienced with messy chemistry and inevitable origin of life. We thank EU-Mobility program for his support in 2018-2020.
For more details, see his recent paper: https://www.nature.com/articles/s42004-018-0031-1
615 000 CPU hours were granted in 12th IT4I call for our project entitled: “Collapse kinetics of themoresponsive polymer chain and hydration dynamics”. Denis and Vladimir will be investigating how does the PNIPAM chain collapse, and how does the properties of interfacial water changes near the critical temperature.
More details about projects supported in this IT4I call in Ostrava – link.
We have developed a temperature T-dependent coarse-grained Hamiltonian of polyethylene glycol/oxide (PEG/PEO) in aqueous solution, which may be used in implicit-solvent material models in a wide temperature (i.e., solvent quality) range.
Our approach combined bottom-up approach, i.e., large scale atomistic MD simulations, and top-down closure, when explicitly targeting macroscopic experimental properties, such as scaling of polymer chain length and osmotic pressure equation of state.