Omkar Mohapatra

Here, we report selective covalent assembly of Gram-negative bacteria and synthetic polymers into functional living materials. We discovered that triblock polymers decorated with vinyl sulfone (VS), a motif that forms a stable covalent bond with cysteine residues on surface proteins, yielded stable covalent assembly with bacterial cells. Notably, we found that these assemblies were uniquely cell-type-specific, occurring only in Gram-negative bacteria, highlighting differences in surface structures and the macromolecular diffusion barrier across bacterial species. We also demonstrated that assembling engineered cells into materials results in situ melanin production from living materials, with robust biocontainment and mechanical reinforcement. Spontaneous enrichment of tyrosine-derived red pigments in the supernatant showcases the effect of confinement in a complex biochemical pathway. This work establishes a platform for encoding complex, engineered, and evolved functions of Gram-negative bacteria into synthetic materials, enabling the development of a wide range of material-based bioreactors.

A novel methodology for the synthesis of 1,5-diketones through a one-pot isomerization–methylenation of a variety of allylic alcohols has been established for the first time. This methodology utilizes commercially available palladium acetate and easily accessible BINOL phosphoric acid. Both isomerization of allylic alcohol and oxidation of methanol occurred through a single catalyst. The practical utility of the methodology has been shown by synthesizing substituted pyridines via sequential addition. Mechanistic investigation reveals the isomerization of allylic alcohols to the corresponding ketone, which ultimately undergoes methylenation, leading to 1,5-diketones, having H₂ and H₂O as the only byproduct.