LcrV is a channel size-determining component of the Yop effector translocon of Yersinia.
Delivery of Yop effector proteins by pathogenic Yersinia across the eukaryotic cell membrane requires LcrV, YopB and YopD. These proteins were also required for channel formation in infected erythrocytes and, using different osmolytes, the contact-dependent haemolysis assay was used to study channel size. Channels associated with LcrV were around 3 nm, whereas the homologous PcrV protein of Pseudomonas aeruginosa induced channels of around 2 nm in diameter. In lipid bilayer membranes, purified LcrV and PcrV induced a stepwise conductance increase of 3 nS and 1 nS, respectively, in 1 M KCl. The regions important for channel size were localized to amino acids 127-195 of LcrV and to amino acids 106-173 of PcrV. The size of the channel correlated with the ability to translocate Yop effectors into host cells. We suggest that LcrV is a size-determining structural component of the Yop translocon.
Holmström
A
A
Department of Microbiology, FOA NBC-Defence, S-901 82 Umeå, Sweden.
Olsson
J
J
Cherepanov
P
P
Maier
E
E
Nordfelth
R
R
Pettersson
J
J
Benz
R
R
Wolf-Watz
H
H
Forsberg
A
A
D000818:Animals; D000942:Antigens, Bacterial / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000382:microbiology / Q000473:pathology; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006461:Hemolysis; D006801:Humans; D007473:Ion Channels / Q000502:physiology*; D008051:Lipid Bilayers / Q000378:metabolism; D009154:Mutation; D010957:Plasmids; D052899:Pore Forming Cytotoxic Proteins; D012756:Sheep; D015011:Yersinia pseudotuberculosis / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*
D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D007473:Ion Channels; C043908:LcrV protein, Yersinia; D008051:Lipid Bilayers; D052899:Pore Forming Cytotoxic Proteins; C118546:antigen V, Pseudomonas