Open AccessCloning, Characterization, and Expression of Bartonella henselae p26
Author(s) -
Jonathan Werner,
Feng Shao,
Rickie W. Kasten,
Emir Hodzic,
Bruno B. Chomel,
Stephen W. Barthold
Publication year - 2006
Publication title -
clinical and vaccine immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.649
H-Index - 77
eISSN - 1556-6811
pISSN - 1556-679X
DOI - 10.1128/cvi.00135-06
Subject(s) - bartonella henselae , biology , recombinant dna , virology , microbiology and biotechnology , antiserum , peptide sequence , nucleic acid sequence , gene , antigen , antibody , genetics , serology
In order to identify immunoreactiveBartonella henselae proteins,B. henselae antiserum from an experimentally infected cat was used to screen aB. henselae genomic DNA expression library. One immunoreactive phage clone contained a gene (p26 ) with significant nucleotide identity with orthologs in brucellae, bartonellae, and several plant-associated bacteria.p26 gene sequences from fourB. henselae strains, oneB. koehlerae strain, and oneB. clarridgeiae strain were cloned. Comparative nucleotide sequence analysis showed thatp26 is a potential marker for molecular diagnosis of infection, as well as for identification to species level and genotyping ofBartonella sp. isolates. Alignment of the predicted amino acid sequences illustrated conserved putative protein features including a hydrophobic transmembrane region, a peptide cleavage site, and four dominant antigenic sites. Expression ofp26 inEscherichia coli produced two proteins (26 and 27.5 kDa), both of which were reactive with feline anti-B. henselae antisera. Furthermore, murine hyperimmune serum raised against either recombinant protein reacted with both proteins. No reactivity to either recombinant protein was detected in nonimmune serum, and reactivity persisted as long as 20 weeks for one cat. Thep26 protein product is an immunodominant antigen that is expressed during infection in cats as a preprotein and is subsequently cleaved to form mature P26.