Pilus biogenesis at the outer membrane of Gram-negative bacterial pathogens

Pili belong to a broad class of bacterial surface structures that play a key role in infection and pathogenicity. The largest and best characterised pilus biogenesis system — the chaperone–usher pathway — is particularly remarkable in its ability to synthesise and display highly organised structures at the outer membrane without any input from endogenous energy sources. The past few years have heralded exciting new developments in our understanding of the structural biology and mechanism of pilus assembly, which are discussed in this review. Such knowledge will be particularly important in the future, as we approach an era of widespread resistance to common antibiotics and require new targets.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (361 K)Download as PowerPoint slideResearch highlights► Crystal structure of the full-length usher transporting the chaperone:adhesin complex. ► New model for pilus assembly by the chaperone–usher pathway. ► Determination of subunit polymerisation rate by electrospray mass spectrometry. ► Shear force applied on the pilus rules the adhesin affinity for the cognate sugar.