Identification of an immuno-dominant protein from Klebsiella pneumoniae strains causing pyogenic liver abscess: implication in serodiagnosis
Resource
BMC Microbiol., 14,
Journal
BMC Microbiology
Pages
321
Date Issued
2014
Date
2014
Author(s)
Abstract
Background: Klebsiella pneumoniae has emerged worldwide as a cause of pyogenic liver abscess (PLA) often complicated by meningitis and endophthalmitis. Early detection of this infectious disease will improve its clinical outcome. Therefore, we tried to isolate immunodominant proteins secreted by K. pneumoniae strains causing PLA.
Results: The secreted proteins of the NTUH-K2044 strain were separated by two-dimensional electrophoresis and then immunoblotted using convalescent sera from patients with K. pneumoniae PLA. A similar to 30-kDa immunodominant protein was then identified. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed an open reading frame (KP1_p307) located on the pK2044 plasmid and bioinformatic analysis identified this protein as a signal peptide of unknown function. The KP1_p307 gene was more prevalent in PLA strains and capsular type K1/K2 strains, but disruption of this gene in NTUH-K2044 strain did not decrease virulence in mice. Ten of fourteen (71%) sera from patients with K. pneumoniae PLA were immunoreactive with the recombinant KP1_p307 protein. Seroconversion demonstrated by a rise in serum titer in serial serum samples confirmed that antibodies against the KP1_p307 protein were elicited after infection.
Conclusions: The KP1_p307 protein could be used as an antigen for early serodiagnosis of K. pneumoniae PLA, particularly in K1/K2 PLA strains.
Results: The secreted proteins of the NTUH-K2044 strain were separated by two-dimensional electrophoresis and then immunoblotted using convalescent sera from patients with K. pneumoniae PLA. A similar to 30-kDa immunodominant protein was then identified. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed an open reading frame (KP1_p307) located on the pK2044 plasmid and bioinformatic analysis identified this protein as a signal peptide of unknown function. The KP1_p307 gene was more prevalent in PLA strains and capsular type K1/K2 strains, but disruption of this gene in NTUH-K2044 strain did not decrease virulence in mice. Ten of fourteen (71%) sera from patients with K. pneumoniae PLA were immunoreactive with the recombinant KP1_p307 protein. Seroconversion demonstrated by a rise in serum titer in serial serum samples confirmed that antibodies against the KP1_p307 protein were elicited after infection.
Conclusions: The KP1_p307 protein could be used as an antigen for early serodiagnosis of K. pneumoniae PLA, particularly in K1/K2 PLA strains.
Subjects
Klebsiella pneumoniae
Pyogenic liver abscess
Antigen
Serodiagnosis
SDGs
Other Subjects
bacterial protein; KP1 p307 protein; recombinant protein; signal peptide; unclassified drug; bacterial protein; bacterium antibody; virulence factor; animal experiment; animal model; antibody detection; Article; bacterial capsule; bacterial gene; bacterial virulence; bioinformatics; clinical article; controlled study; female; gene; gene disruption; gene location; human; immunoblotting; immunoreactivity; Klebsiella pneumoniae; Klebsiella pneumoniae infection; liquid chromatography; mouse; nonhuman; open reading frame; plasmid; protein analysis; protein function; protein secretion; proteomics; pyogenic liver abscess; sensitivity and specificity; seroconversion; serodiagnosis; tandem mass spectrometry; two dimensional electrophoresis; animal; Bagg albino mouse; biology; blood; chemistry; disease model; early diagnosis; gene deletion; immunology; isolation and purification; Klebsiella Infections; Klebsiella pneumoniae; Liver Abscess, Pyogenic; metabolism; microbiology; molecular weight; pathogenicity; pathology; procedures; serology; two dimensional gel electrophoresis; virulence; Klebsiella pneumoniae; Mus; Animals; Antibodies, Bacterial; Bacterial Proteins; Chromatography, Liquid; Computational Biology; Disease Models, Animal; Early Diagnosis; Electrophoresis, Gel, Two-Dimensional; Female; Gene Deletion; Humans; Immunoblotting; Klebsiella Infections; Klebsiella pneumoniae; Liver Abscess, Pyogenic; Mice, Inbred BALB C; Molecular Weight; Open Reading Frames; Serologic Tests; Tandem Mass Spectrometry; Virulence; Virulence Factors