Abstract

Bacterial cellulose (BC) is a sustainable biomaterial with excellent mechanical properties and broad application potential. Controlling BC structure and properties is important for its expanding applications and advancing industrial translation. Here, we establish a high-efficiency, seamless genome-editing system for Komagataeibacter xylinus based on mutant pheS gene and apply it to systematically evaluate the roles of bacterial cellulose synthesis ( bcs ) operon genes in BC production and properties. We found deletion of bcsCⅡ gene markedly enhances BC mechanical properties in K. xylinus P1: tensile strength and Young’s modulus reach 3.56-fold and 2.36-fold improvement, respectively. Multiscale structural analyses indicate that the enhancements arise from more uniform nanofibril assembly and a denser hierarchical network of BC. We further demonstrate that co-culture strategy or inducible expression of bcsCⅡ enable programmable control of BC mechanical properties. Collectively, this work provides an efficient genetic toolkit for K. xylinus , systematically reveals functional roles of bcs operon genes in BC assembly, and offers a rational route to engineer programmable high-performance BC materials.