Through cell membrane immobilization or intracellular uptake of semiconductors, light-driven fixation of CO₂ to commodity chemicals has been achieved. Whereas, the direct contact would impair living cells, which impedes their sustainability.

Recently, a research team led by Prof. Zhong Chao from the Shenzhen Institute of Advanced Technology (SIAT) of the Chinese Academy of Sciences proposed the use of photocatalyst-mineralized biofilms as living bio-abiotic interfaces to implement diverse photocatalytic applications.

The research was published in Science Advances on May 7.

Biofilms are natural consortia embedded within a slimy extracellular matrix. Due to their superior resilience to external environmental stresses, biofilms have been adopted for the design of engineered living materials (ELMs) with applications in underwater adhesion, catalyst immobilization and medical therapy.

The researchers adopted E. coli biofilms with amyloid curli fibers. A7 peptides were first fused to curli subunit CsgA protein to create CsgAA7 nanofibers. It endowed biofilms with capability of in situ mineralization of CdS nanoparticles (NPs).

The photocatalyst-mineralized biofilms were obtained and directly used in photo-catalytic applications after cultivation. Through segregation of CdS NPs from bacterial cells, the system could retain the catalytic property as well as alleviate the impairment.