Engineered Marine Biofilms for Ocean Environment Monitoring.

Marine bacteria offer a promising alternative for developing Engineered Living Materials (ELMs) tailored to marine applications. We engineered Dinoroseobacter shibae to increase its surface-associated growth and develop biosensors for ocean environment monitoring. By fusing the endogenous extracellular matrix amyloidogenic protein CsgA with mussel foot proteins, we significantly increased D. shibae biofilm formation. Additionally, D. shibae was engineered to express the tyrosinase enzyme to further enhance microbial attachment through post-translational modifications of tyrosine residues. By exploiting D. shibae's natural genetic resources, two environmental biosensors were created to detect temperature and oxygen. These biosensors were coupled with a CRISPR-based recording system to store transient gene expression in stable DNA arrays, enabling long-term environmental monitoring. These engineered strains highlight D. shibae's potential in advancing marine microbiome engineering for innovative biofilm applications, including the development of natural, self-renewing biological adhesives, environmental sensors, and "sentinel" cells equipped with CRISPR-recording technology to capture and store environmental signals.