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Biology subjects

Matej, K.

Publications and source records attributed to Matej, K..

2 recordsLinked to original sources

Engineering Spatial Control of Bacterial Organelles

Bacteria were once thought to lack organelles, but it is now clear they confine cellular reactions using an array of membrane- and protein-based compartments. A central question, however, is how bacterial organelles are organized in the cell, and whether their spatial control can be engineered. Here, we show that a two-protein system (McdAB) that positions carboxysomes - CO2-fixing organelles found in autotrophic bacteria - can be repurposed to provide programmable spatial control to diverse organelles in Escherichia coli. McdAB not only restores proper assembly and positioning of heterologously produced carboxysomes in E. coli, but can also be reprogrammed to spatially organize all other known types of bacterial organelles, including encapsulins, biomolecular condensates, and even membrane-bound organelles. Programmable spatial organization of bacterial organelles establishes a new design principle for synthetic biology, where the location of reactions is as tunable as their content. Our work paves the way for more efficient biocatalysis in engineered microbes.

microbiology↗

Surface remodeling and inversion of cell-matrix interactions underlies community recognition and dispersal in Vibrio cholerae biofilms

Biofilms are ubiquitous surface-associated bacterial communities embedded in an extracellular matrix. While it is commonly assumed that biofilm-dwelling cells are glued together by the matrix, how the cell-matrix interaction depends on the specific biochemistry of the matrix components and how this interaction varies during biofilm growth remains unclear. Here, we investigated cell-matrix interactions in Vibrio cholerae (Vc), the causative agent of cholera. We combine genetics, microscopy, simulation, and biochemical tools to show that Vc cells are not attractive to Vibrio polysaccharide (VPS), the main matrix component, but they can be bridged with each other and to the VPS network through crosslinking by Bap1. Downregulation of VPS and surface trimming by the polysaccharide lyase RbmB cause surface remodeling as biofilms age, shifting the nature of cell-matrix interactions from attractive to repulsive and facilitating cell dispersal as aggregated groups. Our results suggest a new conceptual model in understanding the intricate cell-matrix interaction as the major driver for biofilm development, which is potentially generalizable to certain other biofilm-forming species and exopolysaccharides.

biophysics↗