The brighter side of amyloid aggregation: biological nanotubes as support for enzyme photo-immobilization

CHAVES, ANALíA SILVINA; ROMERO, CINTIA MARIANA; GONZALEZ LIZARRAGA, FLORENCIA; BORSARELLI, CLAUDIO DARíO; PERA, LICIA MARÍA; BAIGORI, MARIO DOMINGO; CHEHIN, ROSANA NIEVES

San Miguel de Tucumán

Congreso; XLI Reunión Anual de la Sociedad Argentina de Biofísica; 2012

SAB

Amyloid fibrils are highly ordered protein aggregates which are formed through a self-assembly process when a protein is converted into a cross â-structure in which sheet?sheet interactions are perpendicular to the fibril axis. It is now widely known that the ability to form amyloid fibrils is a common property of polypeptides, although efficient preparation of amyloid fibrils is difficult to achieve for most proteins. Nowaday, fibrils have attracted growing interest as new biomaterials due to their high mechanical, chemical, and structural properties. In the present work, we report the covalent photo-immobilization of a microbial lipase (EC 3.1.1.3) from Brevibacillus agri, onto amyloid fibrils prepared from lysozyme by using a photosensitization technique with visible light. The lipase activity was retained upon photo-attachment and centrifugation. Successful immobilization was determined using electrophoresis, and lipase activity assay. Lipases catalyze hydrolysis of triglycerides at oil?water interfaces. This is a reversible reaction and the enzyme also catalyzes ester synthesis under microaqueous conditions. The catalytic activity of lipases was tested by hydrolysis of p-nitrophenyl palmitate (pNPP). Using amyloid fibrils, we have obtained photo-immobilized lipases in a single-step, clean and fast fashion, and with remarkable efficiency that were assessed based on activity, stability, robustness, and reusability. The immobilized lipase on amyloid fibrils was able to catalyze hydrolysis and synthesis reactions. These results could acquire relevance in the biotechnological uses of amyloid aggregation as an immobilization platform can lead to the development of a new type of immobilized catalysts. Acknowledgements This work was supported by grants CIUNT 26/D409 (UNT) and PIP 297 (CONICET)