Photosensitized Formation of Soluble Bionanoparticles of Lysozyme

VALENTINA REY; INÉS ABATEDAGA; CECILIA VERA; FAUSTINO E. MORÁN VIEYRA; CLAUDIO D. BORSARELLI

Chem Select

Wiley-WCH

Lugar: Weinheim; Año: 2021 vol. 2021 p. 13443 - 13451

2365-6549

Photosensitized crosslinking of hen egg-white lysozyme (LZ) in buffer solutions was obtained by blue-LED excitation of ruthenium (II) tris-bipyridyl dication (Ru(bpy)32+) in a molar excess of persulfate anion (S2O8 2- ), both in the absence and presence of dissolved oxygen. The results show a rapid monomer consumption of >75%, with sequential formation of soluble LZ nanoparticles, e. g., dimers (LZ2),…n-mers (LZn6) with diameters from 6 to 13 nm, regardless of the presence of dissolved oxygen in solution. The bionanoparticles are cross linked through 3,3´-dityrosine (diTyr) bonds, by the recombination of tyrosyl radicals of Y20, Y23, and Y53 residues of different protein molecules, produced by intermediated oxidants Ru-(bpy)3 3+ and SO4•- under aerobic conditions, photosensitized formation of singlet molecular oxygen (1O2) also results in the oxidative transformation of tryptophan residues into fluorescent kynureninetypederivatives. These findings may contribute to the rational development of functional protein bionanoparticles.