Fig. 3: Molecular organization of the diffocin baseplate.
From: Atomic structures of a bacteriocin targeting Gram-positive bacteria
a Longitudinal (left) and transversal (right) cut views of the cryoEM map of the diffocin baseplate in the pre-contraction state. b Ribbon diagram of the spike trimer. A monomer is colored according to the linear diagram. At the tip of the spike, His72 and His74 from three monomers collectively chelate with an iron ion. Comparison of the central parts of the diffocin (c) and R-type pyocin (d) baseplates. e Linear schematic and ribbon diagram of the hub-hydrolase. The hub (blue), lytic transglycosylase (yellow) and endopeptidase (red) are connected sequentially through linkers (gray). The catalytic centers of two hydrolases are labeled with pentagrams. f Zoom-in views of the catalytic triad of hydrolases. The lytic transglycosylase and endopeptidase cleave glycosidic bonds and peptide bonds of the peptidoglycan mesh, respectively. NAG N-acetylglucosamine, NAM N-acetylmuramic acid.
