Open AccessA unique bacterial secretion machinery with multiple secretion centers
Author(s) -
Liqiang Song,
John D. Perpich,
Chenggang Wu,
Thierry Doan,
Zuzanowakowska,
Jan Potempa,
Peter J. Christie,
Eric Cascalès,
Richard J. Lamont,
Bo Hu
Publication year - 2022
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2119907119
Subject(s) - periplasmic space , secretion , bacterial outer membrane , biology , microbiology and biotechnology , cell envelope , virulence , cytoplasm , context (archaeology) , motility , transport protein , bacterial cell structure , bacteria , escherichia coli , gene , genetics , biochemistry , paleontology
Significance The newly described type IX secretion systems (T9SSs) translocate virulence factors and can mediate specialized gliding motility among bacterial pathogens of theFibrobacteres–Chlorobi–Bacterioidetes superphylum. We visualized the spatial organization of the T9SS in its native context in thePorphorymonas gingivalis cell by cryoelectron tomography. The T9SS exhibits distinct symmetries across the bacterial cell envelope: a cytoplasmic complex requiring PorL and PorM for assembly exhibits 12-fold symmetry; a periplasmic complex composed of PorM exhibits 18-fold symmetry and attaches to a PorKN ring near the outer membrane; and eight Sov translocons are arranged with 8-fold symmetry at the cell surface. The T9SS is the largest of the known bacterial secretion systems and evidently arranges as multiple, independently functioning translocation motors.