1887

Abstract

Apo-transferrin (apo-hTf) and holo-transferrin (holo-hTf) were separately conjugated to 15-nm colloidal gold. Iron-restricted strain SD (B:15:P1.16) bound up to three-fold more holo-hTf than apo-hTf (p<0.001). The ability of meningococcal mutants lacking either transferrin-binding protein A (TbpA) or TbpB to discriminate between apo-hTf and holo-hTf was also investigated. There was no significant difference between the amount of gold-labelled apo-transferrin bound by the isogenic TbpA mutant (expressing TbpB) and the parent strain, whereas an isogenic TbpB mutant (expressing TbpA) bound significantly less gold-labelled apo-hTf. The isogenic TbpA and TbpB mutants and the parent strain all bound significantly more holo-hTf than apo-hTf, whereas the double ‘knock-out’ mutant failed to bind hTf irrespective of the iron-loading. In the isogenic mutants, TbpB was more effective in binding either apo- or holo-hTf than TbpA. Monoclonal antibodies against TbpA and TbpB were used to co-localise the transferrin-binding proteins on strain SD. The ratio of TbpA:TbpB was approximately 1:1. TbpA and TbpB were occasionally observed in close proximity to each other, but the two proteins were generally quite separate, which may indicate that they do not usually form a complex to act as a transferrin receptor.

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1998-03-01
2024-04-19
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References

  1. Bullen J. J., Rogers H. J., Griffiths E. Role of iron in bacterial infection. Curr Top Microbiol Immunol 1978; 80:1–35
    [Google Scholar]
  2. Bonnah R. A., Yu R., Schryvers A. B. Biochemical analysis of lactoferrin receptors in the Nesseriaceae: identification of a second bacterial lactoferrin receptor protein. Microb Pathog 1995; 19:285–297
    [Google Scholar]
  3. Ala’Aldeen D. A. A., Davies H. A., Wall R. A., Borriello S. P. The 70 kilodalton iron regulated protein of Neisseria meningitidis is not the human transferrin receptor. FEMS Microbiol Lett 1990; 69:37–42
    [Google Scholar]
  4. Ala’Aldeen D. A. A., Powell N. B. L., Wall R. A., Borriello S. P. Localization of the meningococcal receptors for human transferrin. Infect Immun 1993; 61:751–759
    [Google Scholar]
  5. Palmer H. M., Powell N. B. L., Ala’Aldeen D. A., Wilton J., Borriello S. P. Neisseria meningitidis transferrin-binding protein 1 expressed in Escherichia coli is surface exposed and binds human transferrin. FEMS Microbiol Lett 1993; 110:139–146
    [Google Scholar]
  6. Schryvers A. B., Morris L. J. Identification and characterization of the transferrin receptor from Neisseria meningitidis. Mol Microbiol 1988; 2:281–288
    [Google Scholar]
  7. Schryvers A. B., Lee B. C. Comparative analysis of the transferrin and lactoferrin binding proteins in the family Neisseriaceae. Can J Microbiol 1989; 35:409–415
    [Google Scholar]
  8. Simonson C., Brener D., DeVoe I. W. Expression of a high-affinity mechanism for acquisition of transferrin iron by Neisseria meningitidis. Infect Immun 1982; 36:107–113
    [Google Scholar]
  9. Tsai J., Dyer D. W., Sparling P. F. Loss of transferrin receptor activity in Neisseria meningitidis correlates with inability to use transferrin as an iron source. Infect Immun 1988; 56:3132–3138
    [Google Scholar]
  10. Ala’Aldeen D. A., Stevenson P., Griffiths E. Immune responses in humans and animals to meningococcal transferrinbinding proteins: implications for vaccine design. Infect Immun 1994; 62:2984–2990
    [Google Scholar]
  11. Rokbi B., Mazarin V., Maitre-Wilmotte G., Quentin-Millet M.-J. Identification of two major families of transferrin receptors among Neisseria meningitidis strains based on antigenic and genomic features. FEMS Microbiol Lett 1993; 110:51–58
    [Google Scholar]
  12. Griffiths E., Stevenson P., Ray A. Antigenic and molecular heterogeneity of the transferrin binding protein of Neisseria meningitidis. FEMS Microbiol Lett 1990; 69:31–36
    [Google Scholar]
  13. Blanton K. J., Biswas G. D., Tsai J. Genetic evidence that Neisseria gonorrhoeae produces specific receptors for transferrin and lactoferrin. J Bacteriol 1990; 172:5225–5235
    [Google Scholar]
  14. Comelissen C. N., Sparling P. F. Binding and surface exposure characteristics of the gonococcal transferrin receptor are dependent on both transferrin-binding proteins. J Bacteriol 1996; 178:1437–1444
    [Google Scholar]
  15. Irwin S. W., Averil N., Cheng C. Y., Schryvers A. B. Preparation and analysis of isogenic mutants in the transferrin receptor protein genes, tbp A and tbp B, from Neisseria meningitidis. Mol Microbiol 1993; 8:1125–1133
    [Google Scholar]
  16. Pintor M., Ferron L., Gomez J. A., Gorringe A., Criado M. T., Ferreirós C. M. Blocking of iron uptake by monoclonal antibodies specific for the Neisseria meningitidis transferrinbinding protein 2. J Med Microbiol 1996; 45:252–257
    [Google Scholar]
  17. Comelissen C. N., Sparling P. F. Iron piracy: acquisition of transferrin-bound iron by bacterial pathogens. Mol Microbiol 1994; 14:843–850
    [Google Scholar]
  18. Yu R. H., Schryvers A. B. The interaction between human transferrin and transferrin binding protein 2 from Moraxella (Bramhamella) catarrhalis differs from that of other human pathogens. Microb Pathog 1993; 15:433–445
    [Google Scholar]
  19. Irwin S. W., Yu R. H., Alcantara J., Schryvers A. B. Transferrin and lactoferrin receptor proteins of Neisseria meningitidis. In Condez-Glez C. J., Morse S., Rice P., Sparling P. F., Calderon E. (eds) Pathobiology and immunology of Neisseriaceae Mexico: Publications Office of the National Institute of Public Health, Mexico; 1992392–397
    [Google Scholar]
  20. Williams P., Griffiths E. Bacterial transferrin receptors-structure, function and contribution to vimlence. Med Microbiol Immunol 1992; 181:301–322
    [Google Scholar]
  21. Anderson J. E., Sparling P. F., Comelissen C. N. Gonococcal transferrin-binding protein 2 facilitates but is not essential for transferrin utilization. J Bacteriol 1994; 176:3162–3170
    [Google Scholar]
  22. Comelissen C. N., Biswas G. D., Sparling P. F. Expression of gonococcal transferrin-binding protein 1 causes Escherichia coli to bind human transferrin. J Bacteriol 1993; 175:2448–2450
    [Google Scholar]
  23. Comellisen C. N., Biswas G. D., Tsai J., Paruchuri D. K., Thompson S. A., Sparling P. F. Gonococcal transferrin-binding protein 1 is required for transferrin utilization and is homologous to TonB-dependent outer membrane receptors. J Bacteriol 1992; 174:5788–5797
    [Google Scholar]
  24. Pintor M., Ferron L., Gonez J. A. Blocking of iron uptake from transferrin by antibodies against the transferrin binding proteins in Neisseria meningitidis. Microb Pathog 1996; 20:127–139
    [Google Scholar]
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