Phenotypic characterization of OmpX, an Ail homologue of Yersinia pestis KIM.
The goal of this study was to characterize the Yersinia pestis KIM OmpX protein. Yersinia spp. provide a model for studying several virulence processes including attachment to, and internalization by, host cells. For Yersinia enterocolitica and Yersinia pseudotuberculosis, Ail, YadA and Inv, have been implicated in these processes. In Y. pestis, YadA and Inv are inactivated. Genomic analysis of two Y. pestis strains revealed four loci with sequence homology to Ail. One of these genes, designated y1324 in the Y. pestis KIM database, encodes a protein designated OmpX. The mature protein has a predicted molecular mass of 17.47 kDa, shares approximately 70 % sequence identity with Y. enterocolitica Ail, and has an identical homologue, designated Ail, in the Y. pestis CO92 database. The present study compared the Y. pestis KIM6(+) parental strain with a mutant derivative having an engineered disruption of the OmpX structural gene. The parental strain (and a merodiploid control strain) expressed OmpX at 28 and 37 degrees C, and the protein was detectable throughout all phases of growth. OmpX was required for efficient adherence to, and internalization by, cultured HEp-2 cell monolayers and conferred resistance to the bactericidal effect of human serum. Deletion of ompX resulted in a significantly reduced autoaggregation phenotype and loss of pellicle formation in vitro. These results suggest that Y. pestis OmpX shares functional homology with Y. enterocolitica Ail in adherence, internalization into epithelial cells and serum resistance.
Kolodziejek
Anna M
AM
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Sinclair
Dylan J
DJ
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Seo
Keun S
KS
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Schnider
Darren R
DR
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Deobald
Claudia F
CF
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Rohde
Harold N
HN
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Viall
Austin K
AK
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Minnich
Scott S
SS
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Hovde
Carolyn J
CJ
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Minnich
Scott A
SA
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
Bohach
Gregory A
GA
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA.
D000595:Amino Acid Sequence; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001770:Blood Bactericidal Activity; D002460:Cell Line; D019295:Computational Biology; D004847:Epithelial Cells / Q000382:microbiology; D017353:Gene Deletion; D006801:Humans; D006867:Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010641:Phenotype; D020543:Proteome; D017386:Sequence Homology, Amino Acid; D015010:Yersinia pestis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*
C069712:Ail protein, Yersinia enterocolitica; D001425:Bacterial Outer Membrane Proteins; D020543:Proteome; D006867:Hydrolases