The lab of Professor Jun Liu, Ph.D., along with fellow members of the Yale Microbial Sciences Institute and Department of Microbial Pathogenesis, has developed a highly innovative approach combining in-situ cryo-electron microscopy (cryo-EM) and cryo-electron tomography (cryo-ET) to study the Dot/Icm type IVB secretion system in Legionella. Remarkably, in situ cryo-EM enabled the group to reveal the intact structure of the Dot/Icm machine at near-atomic resolution. In addition, cryo-ET captured the active state of the machine, revealing a transenvelope channel that likely facilitates the direct transport of effector proteins from the bacterial cytoplasm into host cells.
Please read the full research article on BioRxiv: In-situ structures of the Legionella Dot/Icm T4SS identify the DotA-IcmX complex as the gatekeeper for effector translocation. Please also view more publications from the work's lead author, Postdoctoral Associate Jian Yue, Ph.D., and the Liu lab.