INV-21044
The curli system is the primary structural component of bacterial biofilm that promotes bacterial adhesion. This system is composed of highly robust amyloid nanofibers that have self-assembly properties and high resistance to harsh environmental conditions. Such unique properties make these nanofibers attractive for the production of gel and film useful in numerous applications, from food coating, food packaging, drug delivery systems, regenerative medicine to bioelectronics. Curli amyloid nanofibers can also be used as filler in alginate hydrogels. Alginate hydrogels, which are biocompatible, biodegradable, and low-cost, can be used in various biomedical applications as well as in the food industry. Bioengineered bacteria can be relatively simple and cheap solutions to produce curli nanofibers. Nevertheless, large-scale production of bioengineered curli nanofibers is still a challenge and more efficient methods should be devised.
This technology introduces a simple versatile process for making hydrogels and films from curli nanofibers at a large scale with desired functions. Curli fibers produced in this invention enable various modifications that make them suitable for different applications. They can be produced like naturally occurring nanofibers or they can include mutations, fusion proteins, linkers, tags, and many other modifications, which determine the activity of polypeptides. The amount of curli nanofibers in natural hydrogels can vary from 3% to 20%. Hydrogels made in this invention can be accompanied by cells, polysaccharides, surfactants (with varying percentages), nucleotides, extracellular components, nanoparticles, and many other compounds. Hydrogels can be administered in different formats such as injectable or spraying. They can have a storage modulus of 50-1000 pascal, indicating high elasticity potential for the hydrogels. The pattern of nanofibers linkage can be different, which gives the hydrogel flexibility or rigidity. Such flexibility in the design and production of curli nanofibers noticeably enhances the properties of engineered gel and films useful in numerous applications.