As she prepares to defend her PhD thesis in just over a month from now, Tiffany Leighton’s latest work on what happens to type IV pilus function when the PilN and PilO components of the machine are stapled together with disulfide bonds was accepted for publication the Journal of Biological Chemistry. This work helped us to understand that the normal stoichiometry of these proteins is probably a tetramer (PilN and PilO homodimers forming a heterodimer). These data helped to explain a puzzling result from earlier work, where we tried to block PilNO interactions by mutating PilN’s core face, without success. Now it’s clear that those mutations would only affect PilN’s interaction with itself. She also found that deleting motor proteins PilBTU or PilC had no effect on PilNO heterodimer formation, and that some PilNO mutations blocked retraction but not extension of pili. These results help us to understand how the pilus machine works. Congratulations Tiffany!