ArticleInfection and immunity2009
An immunogenic, surface-exposed domain of Haemophilus ducreyi outer membrane protein HgbA is involved in hemoglobin binding.
Article in Infection and immunity, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
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Who cites it
12 citing papers in PubMed, 16 citations in OpenAlex.
- Article
- Pirates of the haemoglobin.Microbial cell (Graz, Austria) · 2022Review
- Application of TonB-Dependent Transporters in Vaccine Development of Gram-Negative Bacteria.Frontiers in cellular and infection microbiology · 2020Review
- Dissecting binding of a β-barrel membrane protein by phage display.Molecular bioSystems · 2017Article
- Heme uptake in bacterial pathogens.Current opinion in chemical biology · 2014Review
- Structure of the hemoglobin-IsdH complex reveals the molecular basis of iron capture by Staphylococcus aureus.The Journal of biological chemistry · 2014Article
- Mutational analysis of hemoglobin binding and heme utilization by a bacterial hemoglobin receptor.Journal of bacteriology · 2013Article
- Extracellular heme uptake and the challenges of bacterial cell membranes.Current topics in membranes · 2012Article
- Structural basis for hemoglobin capture by Staphylococcus aureus cell-surface protein, IsdH.The Journal of biological chemistry · 2011Article
- Passive immunization with a polyclonal antiserum to the hemoglobin receptor of Haemophilus ducreyi confers protection against a homologous challenge in the experimental swine model of chancroid.Infection and immunity · 2011Article
- Immunization with the Haemophilus ducreyi hemoglobin receptor HgbA with adjuvant monophosphoryl lipid A protects swine from a homologous but not a heterologous challenge.Infection and immunity · 2010Article
- Host-pathogen interplay of Haemophilus ducreyi.Current opinion in infectious diseases · 2010Review
Corrections and comments
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Authors and funding
7 authors at 2 institutions in 2 countries.
Funding
Abstract
HgbA is the sole TonB-dependent receptor for hemoglobin (Hb) acquisition of Haemophilus ducreyi. Binding of Hb to HgbA is the initial step in heme acquisition from Hb. To better understand this step, we mutagenized hgbA by deletion of each of the 11 putative surface-exposed loops and expressed each of the mutant proteins in trans in host strain H. ducreyi FX547 hgbA. All mutant proteins were expressed, exported, and detected on the surface by anti-HgbA immunoglobulin G (IgG). Deletion of sequences in loops 5 and 7 of HgbA abolished Hb binding in two different formats. In contrast, HgbA proteins containing deletions in the other nine loops retained the ability to bind Hb. None of the clones expressing mutant proteins were able to grow on plates containing low concentrations of Hb. Previously we demonstrated in a swine model of chancroid infection that an HgbA vaccine conferred complete protection from a challenge infection. Using anti-HgbA IgG from this study and the above deletion mutants, we show that loops 4, 5, and 7 of HgbA were immunogenic and surface exposed and that IgG directed against loops 4 and 5 blocked Hb binding. Furthermore, loop 6 was cleaved by protease on intact H. ducreyi, suggesting surface exposure. These data implicate a central domain of HgbA (in respect to the primary amino acid sequence) as important in Hb binding and suggest that this region of the molecule might have potential as a subunit vaccine.
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Registered trials
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