BapC autotransporter protein is a virulence determinant of Bordetella pertussis

• Published in: Microbial pathogenesis Vol. 51; no. 3; pp. 169 - 177
• Main Authors: Noofeli, Mojtaba, Bokhari, Habib, Blackburn, Paul, Roberts, Mark, Coote, John G., Parton, Roger
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier India Pvt Ltd 01-09-2011; Elsevier
• Subjects: Adult; Amino Acid Sequence; amino acids; Animals; Antimicrobial peptides; Autotransporter; Bacterial Outer Membrane Proteins - genetics; Bacterial Outer Membrane Proteins - metabolism; Bacteriology; Base Sequence; Biological and medical sciences; Blood Bactericidal Activity; blood serum; Bordetella pertussis; Bordetella pertussis - genetics; Bordetella pertussis - metabolism; Bordetella pertussis - pathogenicity; Cecropin; Disease Models, Animal; Female; Fundamental and applied biological sciences. Psychology; Gene Deletion; Genomes; Humans; Infection; Mice; Microbial Viability; Microbiology; Miscellaneous; Molecular Sequence Data; mutants; Nucleotide sequence; Open reading frames; Pertussis; Polymorphism, Genetic; Pseudogenes; Rodent Diseases - microbiology; Rodent Diseases - pathology; Sequence Alignment; sequence analysis; Sequence Analysis, DNA; Serum - microbiology; Serum resistance; Virulence; Virulence Factors, Bordetella - genetics; Virulence Factors, Bordetella - metabolism; Whooping Cough - microbiology; Whooping Cough - pathology; Autotransporter; Serum resistance; Bordetella pertussis; Resistance; Type V secretion system; Virulence; Bacteria; Serum; Protein
• ISSN: 0882-4010; 1096-1208
• DOI: 10.1016/j.micpath.2011.04.004

A protein designated Bap-5 (GenBank accession no.
AF081494) or BapC (GenBank accession no.
AJ277634) has been identified as a member of the
Bordetella pertussis autotransporter family and the present work suggests that this protein, like the previously characterised BrkA, is a Bvg-regulated serum resistance factor and virulence determinant.
B. pertussis bapC and
brkA,
bapC mutants were created and, like a
brkA mutant, showed greater sensitivity to killing by normal human serum than their parent strains but they were not as sensitive as a
bvg mutant. Competition assays also showed an important role for BapC, like BrkA, in virulence of
B. pertussis in mice after intranasal infection. Moreover, the
bapC and
brkA,
bapC mutants, like the
brkA mutant, were found to be more sensitive to the antimicrobial peptide cecropin P1 than the parent strains. In the genome sequence of
B. pertussis strain Tohama,
bapC is designated as a pseudogene due, in part, to a frameshift in a poly(C) tract near the 5′ end of the gene which creates a truncated BapC protein. Sequence analyses of the
bapC region spanning the poly(C) tract of a number of
B. pertussis strains showed minor nucleotide and amino acid polymorphisms but it appeared that all had an ORF that would be able to produce BapC.