Genetically programmed engineered living materials as high-performance bioplastics

Abstract

Engineered living materials (ELMs) are a class of materials comprising living cells and a polymer (or biopolymer) network that together afford a function, performance, or property that could not be achieved by the individual components. There are limited means to fabricate ELM bioplastics with arbitrary three-dimensional (3D) shapes and requisite physical properties for mechanical performance. Herein, we use programmed bioproduction to tune the stiffness and degradation of ELMs with protein-based matrices. Using genetically engineered Saccharomyces cerevisiae strains, it is possible to induce the production of betaxanthins and proteinase A in response to copper ions and galactose, respectively. The betaxanthins served to enhance the modulus of the bioplastics and reduce the degradative activity of native proteases, whereas proteinase A was produced for the rapid on-demand degradation of the ELM. This biomanufacturing approach provides the means to fabricate ELMs with arbitrary 3D shapes and bio-augmented mechanical properties that also address demands for sustainability.