Towards efficient biocatalysts: photo-immobilization of a lipase on hybrid lysozyme-heparin amyloid nanofibrils

SILVINA CHAVES; CINTIA M ROMERO; RICARDO MIGNONE; CLAUDIO D. BORSARELLI; LICIA M PERA; MARIO BAIGORI; ROSANA CHEHÍN

Sierra de la Ventana (Pcia. de Buenos Aires)

Congreso; XLIII Reunion anual de de la Sociedad Argentina de Biofísica; 2014

Sociedad Argentina de Biofisica

Amyloid fibrils have attracted nowadays a growing interest as new biomaterials due to their special mechanical, chemical, and structural properties, making them an excellent choice for development of novel supports for different technological applications. It is now widely accepted that the ability to form amyloid aggregates is a common property of any polypeptide chains. In fact, specific protocols for each protein have been reported in order to turning them from soluble into highly ordered amyloid aggregates with the characteristic cross-β structures among peptide chains. In the present work, we report the preparation and characterization of a biocatalyst based on the photo-immobilization of a lipase onto hybrid amyloid nanofibrils of heparin and lysozyme. The new hybrid nanomaterial lost both the lysozyme antibiotic activity and its ability to induce changes in membrane permeability. However, the hybrid nanofibrils present key reactive amino acids exposed to the solvent, such as tyrosine residues, which allowed the covalent attach of a lipase molecule through crosslinking via tyrosyl radicals generated by blue-light photosensitization of the metal coordination complex ruthenium (II) tris-bipyridine in the presence of ammonium persulfate. Thus, the photo-immobilized lipase onto the hybrid nanofibrils showed much better enzymatic activity under different extreme conditions of temperature and solvent as compared with the free enzyme. The procedure reported herein could be useful to design a new generation of biocatalyst by a single photo-click step in a clean and faster fashion way than conventional chemical crosslinked procedure.