title: Vaccine candidate P6 of nontypable Haemophilus influenzae is not a transmembrane protein based on protein structural analysis.
abstract: P6 has been a vaccine candidate for nontypable Haemophilus influenzae (NTHi) based on its location on the outer membrane and immunogenicity. Because P6 is attached to the inner peptidoglycan layer of NTHi, and is putatively surface exposed, it must be a transmembrane protein. We examined the P6 structure using computational modeling, site-directed mutagenesis, and nuclear magnetic resonance spectroscopy. We found that P6 cannot be a transmembrane protein, and therefore may not be surface exposed. We conclude that there may be another protein on the surface of NTHi that has epitopes similar if not identical to P6.
authors.affiliation: Department of Chemistry, Rochester Institute of Technology, Rochester, NY, USA.
authors.forename: Lea Vacca
authors.initials: LV
authors.lastname: Michel
authors.forename: Breanna
authors.initials: B
authors.lastname: Kalmeta
authors.forename: Mark
authors.initials: M
authors.lastname: McCreary
authors.forename: Joy
authors.initials: J
authors.lastname: Snyder
authors.forename: Paul
authors.initials: P
authors.lastname: Craig
authors.forename: Michael E
authors.initials: ME
authors.lastname: Pichichero
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000276:immunology; D019295:Computational Biology / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay; D018073:Haemophilus Vaccines / Q000737:chemistry* / Q000276:immunology; D006193:Haemophilus influenzae / Q000737:chemistry*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary
chemical_list: D001425:Bacterial Outer Membrane Proteins; D018073:Haemophilus Vaccines; C069990:P6 outer membrane protein, Haemophilus