Abstract
Summary Type IV pili ( T4P ) are bacterial virulence factors involved in a wide variety of functions including deoxyribonucleic acid uptake, surface attachment, biofilm formation and twitching motility. While T4P are common surface appendages, the systems that assemble them and the regulation of their function differ between species. Pseudomonas aeruginosa , N eisseria spp. and M yxococcus xanthus are common model systems used to study T4P biology. This review focuses on recent advances in P . aeruginosa T4P structural biology, and the regulatory pathways controlling T4P biogenesis and function.