1.C.3.4.1
Leucocidin chain F.  3-D structures of the prepore revealed that this is substantially different from the pore structure.  The structures revealed a disordered bottom half of the beta-barrel corresponding to the transmembrane region, and a rigid upper extramembrane half (Yamashita et al. 2014). LukF can form an octameric pore with 4 subunits of LukF and 4 subunits of LukS (TC# 1.C.3.4.3) (Jayasinghe and Bayley 2005).  Panton-Valentine leukocidin (PVL, encoded by lukSF-PV genes) is a bi-component and pore-forming toxin carried by different staphylococcal bacteriophages (Zhao et al. 2016). The gamma-hemolysin protein is used by the pathogen to escape the immune system of the host, by assembling into octameric transmembrane pores on the surface of the target immune cell, leading to its death by leakage or apoptosis. The  interactions between the individual monomers that lead to the formation of a dimer on the cell membrane, which represents the unit for further oligomerization, has not been defined. Paternoster et al. 2023 determined the stabilizing contacts that guide formation of a functional dimer.