TY - JOUR
T1 - The sequence of events of enteropathogenic E. coli's type III secretion system translocon assembly
AU - Gershberg, Jenia
AU - Morhaim, May
AU - Rostrovsky, Irina
AU - Eichler, Jerry
AU - Sal-Man, Neta
N1 - Publisher Copyright: © 2024 The Author(s)
PY - 2024/3/15
Y1 - 2024/3/15
N2 - Many bacterial pathogens employ the type III secretion system (T3SS), a specialized complex that transports effector proteins that manipulate various cellular processes. The T3SS forms a translocon pore within the host-cell membrane consisting of two secreted proteins that transition from a soluble state into a transmembrane complex. Still, the exact sequence of events leading to the formation of a membranous functional pore remains uncertain. Here, we utilized the translocon proteins of enteropathogenic E. coli (EPEC) to investigate the sequence of those steps leading to translocon assembly, including self-oligomerization, hetero-oligomerization, interprotein interaction, and membrane insertion. We found that in EPEC, EspD (SctE) plays a dominant role in pore formation as it assembles into an oligomeric state, regardless of pH, membrane contact, or the presence of EspB (SctB). Subsequently, EspB subunits integrate into EspD homo-oligomers to create EspB-EspD hetero-oligomers that adopt a transmembrane orientation to create a functional pore complex.
AB - Many bacterial pathogens employ the type III secretion system (T3SS), a specialized complex that transports effector proteins that manipulate various cellular processes. The T3SS forms a translocon pore within the host-cell membrane consisting of two secreted proteins that transition from a soluble state into a transmembrane complex. Still, the exact sequence of events leading to the formation of a membranous functional pore remains uncertain. Here, we utilized the translocon proteins of enteropathogenic E. coli (EPEC) to investigate the sequence of those steps leading to translocon assembly, including self-oligomerization, hetero-oligomerization, interprotein interaction, and membrane insertion. We found that in EPEC, EspD (SctE) plays a dominant role in pore formation as it assembles into an oligomeric state, regardless of pH, membrane contact, or the presence of EspB (SctB). Subsequently, EspB subunits integrate into EspD homo-oligomers to create EspB-EspD hetero-oligomers that adopt a transmembrane orientation to create a functional pore complex.
KW - Microbiology
KW - Molecular biology
UR - http://www.scopus.com/inward/record.url?scp=85187305217&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.isci.2024.109108
DO - https://doi.org/10.1016/j.isci.2024.109108
M3 - Article
C2 - 38375228
SN - 2589-0042
VL - 27
JO - iScience
JF - iScience
IS - 3
M1 - 109108
ER -