JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Bonnah, R. A.
Right arrow Articles by Schryvers, A. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bonnah, R. A.
Right arrow Articles by Schryvers, A. B.

J Bacteriol, June 1998, p. 3080-3090, Vol. 180, No. 12
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Preparation and Characterization of Neisseria meningitidis Mutants Deficient in Production of the Human Lactoferrin-Binding Proteins LbpA and LbpB

Robert A. Bonnah and Anthony B. Schryvers*

Department of Microbiology and Infectious Diseases, University of Calgary, Health Sciences Center, Calgary, Alberta, Canada T2N 4N1

Received 13 January 1998/Accepted 29 March 1998

Pathogenic members of the family Neisseriaceae produce specific receptors facilitating iron acquisition from transferrin (Tf) and lactoferrin (Lf) of their mammalian host. Tf receptors are composed of two outer membrane proteins, Tf-binding proteins A and B (TbpA and TbpB; formerly designated Tbp1 and Tbp2, respectively). Although only a single Lf-binding protein, LbpA (formerly designated Lbp1), had previously been recognized, we recently identified additional bacterial Lf-binding proteins in the human pathogens Neisseria meningitidis and Moraxella catarrhalis and the bovine pathogen Moraxella bovis by a modified affinity isolation technique (R. A. Bonnah, R.-H. Yu, and A. B. Schryvers, Microb. Pathog. 19:285-297, 1995). In this report, we characterize an open reading frame (ORF) located immediately upstream of the N. meningitidis B16B6 lbpA gene. Amino acid sequence comparisons of various TbpBs with the product of the translated DNA sequence from the upstream ORF suggests that the region encodes the Lf-binding protein B homolog (LbpB). The LbpB from strain B16B6 has two large stretches of negatively charged amino acids that are not present in the various transferrin receptor homologs (TbpBs). Expression of the recombinant LbpB protein as a fusion with maltose binding protein demonstrated functional Lf-binding activity. Studies with N. meningitidis isogenic mutants in which the lbpA gene and the ORF immediately upstream of lbpA (putative lbpB gene) were insertionally inactivated demonstrated that LbpA, but not LbpB, is essential for iron acquisition from Lf in vitro.

* Corresponding author. Mailing address: Department of Microbiology and Infectious Diseases, University of Calgary, Heritage Medical Research Bldg., Health Sciences Center, Calgary, Alberta, Canada T2N 4N1. Phone: (403) 220-3703. Fax: (403) 270-2772. E-mail: schryver{at}acs.ucalgary.ca.

J Bacteriol, June 1998, p. 3080-3090, Vol. 180, No. 12
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 1998 by the American Society for Microbiology. All rights reserved.