English: Biohybrid bacterial microswimmers
Biohybrid bacterial microswimmers functionalized with red blood cell (RBC)-membrane nanoliposomes (nanoerythrosomes). (a) Biohybrid bacterial microswimmers are composed of genetically engineered motile E. coli MG1655 substrain and nanoerythrosomes made out of the RBC membranes. Nanoerythrosomes are functionalized on the bacterial membrane via biotin–streptavidin–biotin interaction. The nanoerythrosome membrane is biotinylated by functionalization of TER-119 antibodies with biotin molecules, whereas E. coli MG1655 is bioengineered to express biotin attachment peptides on its membrane and biotin molecules are directly conjugated on its membrane surface. (b) Scanning electron microscopy (SEM) image of the nanoerythrosome functionalized bacterial swimmers. Nanoerythrosomes were conjugated not only to the bacterial body but also to their flagella. (c) A typical swimming trajectory for the biohybrid bacterial microswimmers captured via fluorescent microscopy. The red dot indicates nanoerythrosome on bacteria and the white line shows the swimming trajectory. The inset shows bacteria (green color) functionalized with nanoerythrosomes (red color). The scale bar of the inset is 1 μm.