Naslov
Ovalbumin thermal stability dependence on pH

Autori
Hloušek-Kasun, Andrea ; Bertoša, Branimir ; Sviben, Dora ; Forčić, Dubravko ; Halassy, Beata ; Brgles, Marija

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
The 14 th Greta Pifat Mrzljak International School of Biophysics ABC of Physics of Life: Book of abstracts / - , 2018, 83-83

Skup
The 14 th Greta Pifat Mrzljak International School of Biophysics

Mjesto i datum
Split, Hrvatska, 23.08.2018. - 01.09.2018

Vrsta sudjelovanja
Poster

Vrsta recenzije
Domaća recenzija

Ključne riječi
Molecular dynamics ; Thermal shift assay ; Protein stability

Sažetak
Parameter that highly affects stability of the protein structure is pH since it affects charges of amino acid residues and, therefore, affects intra- and intermolecular noncovalent interactions responsible for protein stability. Protein thermal shift assay (TSA) revealed greater stability of ovalbumin (PDB code: 1OVA) in alkaline conditions (pH= 8) than in acidic conditions (pH= 4). In order to understand molecular basis of ovalbumin’s thermal stability dependence on pH, molecular dynamics simulations at various temperatures and various pH were applied. Two different procedures were used, one for the protein that was simulated at acidic conditions where aspartate and glutamate amino acid residues were protonated, and the other one for the protein that was simulated at alkaline conditions with aspartate and glutamate amino acids deprotonated. Each system, acidic and alkaline, was simulated at five temperatures: 37 °C, 42 °C, 57 °C, 74 °C, and 85 °C. Results of simulations were in agreement with experimental results, it was observed that the instability of the acidic system is much more pronounced than the instability of the alkaline system. The most noticeable difference between these two systems were the H-bond interactions of arginine 50 and arginine 58 with their surrounding residues. In case of the alkaline system, both, Arg50 and Arg58, made higher average number of stronger and more persistent H-bond interactions. The same differences in H-bonding between alkaline and acidic systems were noticed, both, during the simulation at lover and higher temperatures. Different behaviour of Arg50 and Arg58 in acidic and alkaline systems is also supported by the analysis of fluctuations (RMSF).

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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