Imperial College London


Faculty of MedicineDepartment of Infectious Disease

Senior Research Fellow



+44 (0)20 7594 3074x.yu




Flowers buildingSouth Kensington Campus





Upon infection of mammalian host cells, Salmonella Typhimurium resides within acidic membrane-bound compartments known as Salmonella-containing vacuoles (SCVs). In this environment, the type three secretion apparatus (T3SA) encoded by Salmonella pathogenicity island 2 (SPI-2) is assembled, and secretes translocator proteins. An SsaL/SsaM/SpiC regulatory complex is required to form a translocon pore on the membrane of SCV. Once the translocon pore is formed, the neutral pH of host cell cytosol is sensed by the bacterium through an unknown mechanism to dissociate the SsaL/SsaM/SpiC complex and allow secretion and translocation of effector proteins into the host cell. I am interested in understanding how the neutral pH of host cell cytosol is sensed and transduced into the bacterial cytosolic side to dissociate the SsaL/SsaM/SpiC complex, and how the acidic pH triggers the assembly of SPI-2 T3SA.



Pillay TD, Hettiarachchi SU, Gan J, et al., 2023, Speaking the host language: how Salmonella effector proteins manipulate the host, Microbiology, Vol:169, ISSN:1350-0872, Pages:1-30

Matthews-Palmer T, Gonzalez-Rodriguez N, Calcraft T, et al., 2021, Structure of the cytoplasmic domain of SctV (SsaV) from the Salmonella SPI-2 injectisome and implications for a pH sensing mechanism, Journal of Structural Biology, Vol:213, ISSN:1047-8477

Yu X, Grabe G, Liu M, et al., 2018, SsaV interacts with SsaL to control the translocon-to-effector switch in the Salmonella SPI-2 type three secretion system, Mbio, Vol:9, ISSN:2150-7511

Yu XJ, Liu M, Holden D, 2016, Salmonella Effectors SseF and SseG Interact with Mammalian Protein ACBD3 (GCP60) To Anchor Salmonella-Containing Vacuoles at the Golgi Network, Mbio, Vol:7, ISSN:2161-2129

Xie H-X, Lu J-F, Zhou Y, et al., 2015, Identification and Functional Characterization of the Novel <i>Edwardsiella tarda</i> Effector EseJ, Infection and Immunity, Vol:83, ISSN:0019-9567, Pages:1650-1660

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