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Colicin Js
From Proteopedia
Colicin Js is a type of Colicin, a bacteriocin made by E. coli which acts against other nearby E. coli to kill them with its cytotoxic domain; its method of killing is as yet unidentified.
Synthesis and release
The operon for colicin B is encoded on a plasmid in the cytoplasm of the E. coli. This operon also encodes its Colicin Immunity Protein, Cji, to protect the cell from the cytotoxic activities of the colicin, alongside a protein to aid the release of the colicin outside the cell.
Mechanism of uptake
The receptor binding domain of the colicin binds to the outer membrane receptor CjrBC[1] on the target cell; it is a constitutively expressed protein parasitised by the colicin. The translocation domain then recruits proteins from the Ton system to translocate the protein across the membrane and into the cytoplasm.
