The inlA gene of Listeria monocytogenes LO28 harbors a nonsense mutation resulting in release of internalin.
Internalin is a surface protein that mediates entry of Listeria monocytogenes EGD into epithelial cells expressing the cell adhesion molecule human E-cadherin or its chicken homolog, L-CAM, which act as receptors for internalin. After observing that entry of L. monocytogenes LO28 into S180 fibroblasts, in contrast to that of EGD, did not increase after transfection with L-CAM, we examined both the expression and the structure of internalin in strain LO28. We discovered a nonsense mutation in inlA which results in a truncated protein released in the culture medium. Mutations leading to release of internalin were also detected in clinical and food isolates. These results question the role of internalin as a virulence factor in murine listeriosis.
Jonquières
R
R
Unité des Interactions Bactéries-Cellules, Institut Pasteur, Paris, France.
Bierne
H
H
Mengaud
J
J
Cossart
P
P
D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D002460:Cell Line; D005798:Genes, Bacterial; D008089:Listeria monocytogenes / Q000235:genetics* / Q000472:pathogenicity; D051379:Mice; D009154:Mutation; D014774:Virulence
D001426:Bacterial Proteins; C069761:internalin protein, Bacteria