Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Complexation and Thermal Stabilization of Protein-Polyelectrolyte Systems via Experiments and Molecular Simulations: The Poly(acrylic acid)/Lysozyme Case
Δημιουργός/Συγγραφέας:	Tegopoulos, Sokratis N Ektirici, Sisem Harmandaris, Vagelis Kyritsis, Apostolos [EL] Ρισσάνου, Αναστασία[EN] Rissanou, Anastassia [EL] Παπαγιαννόπουλος, Αριστείδης[EN] Papagiannopoulos, Aristeidis
Ημερομηνία:	2025-08-01
Γλώσσα:	Αγγλικά
ISSN:	2073-4360
DOI:	10.3390/polym17152125
Άλλο:	40808173
Περίληψη:	Protein-polyelectrolyte nanostructures assembled via electrostatic interactions offer versatile applications in biomedicine, tissue engineering, and food science. However, several open questions remain regarding their intermolecular interactions and the influence of external conditions-such as temperature and pH-on their assembly, stability, and responsiveness. This study explores the formation and stability of networks between poly(acrylic acid) (PAA) and lysozyme (LYZ) at the nanoscale upon thermal treatment, using a combination of experimental and simulation measures. Experimental techniques of static and dynamic light scattering (SLS and DLS), Fourier transform infrared spectroscopy (FTIR), and circular dichroism (CD) are combined with all-atom molecular dynamics simulations. Model systems consisting of multiple PAA and LYZ molecules explore collective assembly and complexation in aqueous solution. Experimental results indicate that electrostatic complexation occurs between PAA and LYZ at pH values below LYZ's isoelectric point. This leads to the formation of nanoparticles (NPs) with radii ranging from 100 to 200 nm, most pronounced at a PAA/LYZ mass ratio of 0.1. These complexes disassemble at pH 12, where both LYZ and PAA are negatively charged. However, when complexes are thermally treated (TT), they remain stable, which is consistent with earlier findings. Atomistic simulations demonstrate that thermal treatment induces partially reversible structural changes, revealing key microscopic features involved in the stabilization of the formed network. Although electrostatic interactions dominate under all pH and temperature conditions, thermally induced conformational changes reorganize the binding pattern, resulting in an increased number of contacts between LYZ and PAA upon thermal treatment. The altered hydration associated with conformational rearrangements emerges as a key contributor to the stability of the thermally treated complexes, particularly under conditions of strong electrostatic repulsion at pH 12. Moreover, enhanced polymer chain associations within the network are observed, which play a crucial role in complex stabilization. These insights contribute to the rational design of protein-polyelectrolyte materials, revealing the origins of association under thermally induced structural rearrangements.
Τίτλος πηγής δημοσίευσης:	Polymers
Τόμος/Κεφάλαιο:	17
Τεύχος:	15
Θεματική Κατηγορία:	[EL] Βιοχημεία[EN] Biochemistry [EL] Νανοτεχνολογία[EN] Nanotechnology [EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry [EL] Μοριακή Βιολογία[EN] Molecular Biology
Λέξεις-Κλειδιά:	atomic information light scattering molecular dynamics simulations protein–polyelectrolyte complexation thermal stabilization
Κάτοχος πνευματικών δικαιωμάτων:	© 2025 by the authors. Licensee MDPI, Basel, Switzerland.
Όροι και προϋποθέσεις δικαιωμάτων:	This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/ licenses/by/4.0/).
Ηλεκτρονική διεύθυνση στον εκδότη (link):	https://doi.org/10.3390/polym17152125
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο