A Genetically Engineered Biofilm Material for SARS‐CoV‐2 Capturing and Isolation

The novel severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is continuously infecting people all around the world since its outbreak in 2019. Studies for numerous infection detection strategies are continuing. The sensitivity of detection methods is crucial to separate people with mild infections from people who are asymptomatic. In this sense, a strategy that would help to capture and isolate the SARS‐CoV‐2 virus prior to tests can be effective and beneficial. To this extent, genetically engineered biomaterials grounding from the biofilm protein of Escherichia coli are beneficial due to their robustness and adaptability to various application areas. Through functionalizing the E. coli biofilm protein, diverse properties can be attained such as enzyme display, nanoparticle production, and medical implant structures. Here, E. coli species are employed to express major curli protein CsgA and Griffithsin (GRFT) as fusion proteins, through a complex formation using SpyTag and SpyCatcher domains. In this study, a complex system with a CsgA scaffold harboring the affinity of GRFT against Spike protein to capture and isolate SARS‐CoV‐2 virus is successfully developed. It is shown that the hybrid recombinant protein can dramatically increase the sensitivity of currently available lateral flow assays for Sars‐CoV‐2 diagnostics. Escherichia coli major curli biofilm protein is functionalized with Griffithsin (GRFT) through a peptide–protein domain interaction. The resulting complex has been used as a template to develop a genetically engineered biomaterial structure for SARS‐CoV‐2 capture and isolation. Remarkably, the complex structure is capable of effectively capturing and isolating virus particles from aqueous media.