title: A comparative, cross-species investigation of the properties and roles of transferrin- and lactoferrin-binding protein B from pathogenic bacteria.
abstract: Pathogenic bacteria from the families Neisseriaeceae and Moraxellaceae acquire iron from their host using surface receptors that have the ability to hijack iron from the iron-sequestering host proteins transferrin (Tf) and lactoferrin (Lf). The process of acquiring iron from Tf has been well-characterized, including the role of the surface lipoprotein transferrin-binding protein B (TbpB). In contrast, the only well-defined role for the homologue, LbpB, is in its protection against cationic antimicrobial peptides, which is mediated by regions present in some LbpBs that are highly enriched in glutamic or aspartic acid. In this study we compare the Tf-TbpB and the Lf-LbpB interactions and examine the protective effect of LbpB against extracts from human and transgenic mouse neutrophils to gains insights into the physiological roles of LbpB. The results indicate that in contrast to the Tf-TbpB interaction, Lf-LbpB interaction is sensitive to pH and varies between species. In addition, the results with transgenic mouse neutrophils raise the question of whether there is species specificity in the cleavage of Lf to generate cationic antimicrobial peptides or differences in the potency of peptides derived from mouse and human Lf.
authors.affiliation: a Department of Microbiology & Infectious Diseases, University of Calgary, Calgary, AB T2N 4N1, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Ostan
authors.affiliation: b Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.|c School of Medicine, New York Medical College, Valhalla, NY 10595, USA.
authors.forename: A
authors.initials: A
authors.lastname: Morgenthau
authors.affiliation: a Department of Microbiology & Infectious Diseases, University of Calgary, Calgary, AB T2N 4N1, Canada.
authors.forename: R H
authors.initials: RH
authors.lastname: Yu
authors.affiliation: b Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
authors.forename: S D
authors.initials: SD
authors.lastname: Gray-Owen
authors.affiliation: a Department of Microbiology & Infectious Diseases, University of Calgary, Calgary, AB T2N 4N1, Canada.
authors.forename: A B
authors.initials: AB
authors.lastname: Schryvers
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D006801:Humans; D007781:Lactoferrin / Q000378:metabolism*; D008589:Meningococcal Infections / Q000382:microbiology; D051379:Mice; D008822:Mice, Transgenic; D009345:Neisseria meningitidis / Q000378:metabolism* / Q000472:pathogenicity; D009504:Neutrophils / Q000166:cytology / Q000378:metabolism*; D014168:Transferrin / Q000378:metabolism*; D033882:Transferrin-Binding Protein B / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D014168:Transferrin; D033882:Transferrin-Binding Protein B; C027768:lactoferrin binding proteins, bacterial; D007781:Lactoferrin
keywords: bacterial pathogenesis; cationic antimicrobial peptides; iron transport; lactoferrin; lactoferrine; pathogenèse bactérienne; peptides cationiques antimicrobiens; transferrin; transferrine; transport du fer