Selective sorting of cargo proteins into bacterial membrane vesicles.
In contrast to the well established multiple cellular roles of membrane vesicles in eukaryotic cell biology, outer membrane vesicles (OMV) produced via blebbing of prokaryotic membranes have frequently been regarded as cell debris or microscopy artifacts. Increasingly, however, bacterial membrane vesicles are thought to play a role in microbial virulence, although it remains to be determined whether OMV result from a directed process or from passive disintegration of the outer membrane. Here we establish that the human oral pathogen Porphyromonas gingivalis has a mechanism to selectively sort proteins into OMV, resulting in the preferential packaging of virulence factors into OMV and the exclusion of abundant outer membrane proteins from the protein cargo. Furthermore, we show a critical role for lipopolysaccharide in directing this sorting mechanism. The existence of a process to package specific virulence factors into OMV may significantly alter our current understanding of host-pathogen interactions.
Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
M Florencia
MF
Haurat
Joseph
J
Aduse-Opoku
Minnie
M
Rangarajan
Loredana
L
Dorobantu
Murray R
MR
Gray
Michael A
MA
Curtis
Mario F
MF
Feldman
D018829:Adhesins, Bacterial / Q000235:genetics / Q000378:metabolism; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000378:metabolism; D000080867:Gingipain Cysteine Endopeptidases; D008050:Lipid A / Q000378:metabolism; D008070:Lipopolysaccharides / Q000378:metabolism*; D019081:O Antigens / Q000235:genetics / Q000378:metabolism; D016966:Porphyromonas gingivalis / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D021381:Protein Transport / Q000502:physiology*; D022142:Secretory Vesicles / Q000378:metabolism; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
D018829:Adhesins, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D000080867:Gingipain Cysteine Endopeptidases; D008050:Lipid A; D008070:Lipopolysaccharides; D019081:O Antigens; C484343:RagA protein, Porphyromonas gingivalis; C484346:RagB protein, bacteria; D037521:Virulence Factors; D003546:Cysteine Endopeptidases