1887

Abstract

The HmbR outer-membrane receptor enables to use haemoglobin (Hb) as a source of iron. This protein functions by binding Hb, removing haem from it, and releasing the haem into the periplasm. Functionally important HmbR receptor domains were discerned using a series of HmbR deletions and site-directed mutations. Mutations exhibiting similar defective phenotypes in fell into two groups. The first group of mutations affected Hb binding and were located in putative extracellular loops (L) L2 (amino acid residues (aa) 192–230) and L3 (aa 254–284). The second group of mutations resulted in a failure to utilize Hb but proficiency in Hb binding was retained. These mutations localized to the putative extracellular loops L6 (aa 420–462) and L7 (aa 486–516). A highly conserved protein motif found in all haem/Hb receptors, within putative extracellular loop L7 of HmbR, is essential for Hb utilization but not required for Hb binding. This finding suggests a mechanistic involvement of this motif in haem removal from Hb. In addition, an amino-terminal deletion in the putative cork-like domain of HmbR affected Hb usage but not Hb binding. This result supports a role of the cork domain in utilization steps that are subsequent to Hb binding.

Keyword(s): Hb, haemoglobin
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2003-12-01
2024-04-19
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References

  1. Barnard T. J., Watson M. E. Jr, McIntosh M. A. 2001; Mutations in the Escherichia coli receptor FepA reveal residues involved in ligand binding and transport. Mol Microbiol 41:527–536
    [Google Scholar]
  2. Baumler A. J., Hantke K. 1992; Ferrioxamine uptake in Yersinia enterocolitica : characterization of the receptor protein FoxA. Mol Microbiol 6:1309–1321
    [Google Scholar]
  3. Benson S. A., Occi J. L., Sampson B. A. 1988; Mutations that alter the pore function of the OmpF porin of Escherichia coli K12. J Mol Biol 203:961–970
    [Google Scholar]
  4. Boulanger P., le Maire M., Bonhivers M., Dubois S., Desmadril M., Letellier L. 1996; Purification and structural and functional characterization of FhuA, a transporter of the Escherichia coli outer membrane. Biochemistry 35:14216–14224
    [Google Scholar]
  5. Bracken C. S., Baer M. T., Abdur-Rashid A., Helms W., Stojiljkovic I. 1999; Use of heme-protein complexes by the Yersinia enterocolitica HemR receptor: histidine residues are essential for receptor function. J Bacteriol 181:6063–6072
    [Google Scholar]
  6. Braun M., Killmann H., Braun V. 1999; The beta-barrel domain of FhuADelta5–160 is sufficient for TonB-dependent FhuA activities of Escherichia coli . Mol Microbiol 33:1037–1049
    [Google Scholar]
  7. Buchanan S. K. 1999; Beta-barrel proteins from bacterial outer membranes: structure, function and refolding. Curr Opin Struct Biol 9:455–461
    [Google Scholar]
  8. Buchanan S. K., Smith B. S., Venkatramani L., Xia D., Esser L., Palnitkar M., Chakraborty R., van der Helm D., Deisenhofer J. 1999; Crystal structure of the outer membrane active transporter FepA from Escherichia coli . Nat Struct Biol 6:56–63
    [Google Scholar]
  9. Carmel G., Coulton J. W. 1991; Internal deletions in the FhuA receptor of Escherichia coli K-12 define domains of ligand interactions. J Bacteriol 173:4394–4403
    [Google Scholar]
  10. Clarke T. E., Tari L. W., Vogel H. J. 2001; Structural biology of bacterial iron uptake systems. Curr Top Med Chem 1:7–30
    [Google Scholar]
  11. Cope L. D., Thomas C. E., Latimer J. L., Slaughter C. A., Muller-Eberhard U., Hansen E. J. 1994; The 100 kDa haem : haemopexin-binding protein of Hemophilus influenzae : structure and function. Mol Microbiol 13:863–873
    [Google Scholar]
  12. Eisenberg D., Schwarz E., Komaromy M., Wall R. 1984; Analysis of membrane and surface protein sequences with the hydrophobic moment plot. J Mol Biol 179:125–142
    [Google Scholar]
  13. Ferguson A. D., Hofmann E., Coulton J. W., Diederichs K., Welte W. 1998; Siderophore-mediated iron transport: crystal structure of FhuA with bound lipopolysaccharide. Science 282:2215–2220
    [Google Scholar]
  14. Ferguson A. D., Chakraborty R., Smith B. S., Esser L., van der Helm D., Deisenhofer J. 2002; Structural basis of gating by the outer membrane transporter FecA. Science 295:1715–1719
    [Google Scholar]
  15. Genco C. A., Dixon D. W. 2001; Emerging strategies in microbial haem capture. Mol Microbiol 39:1–11
    [Google Scholar]
  16. Gray-Owen S. D., Schryvers A. B. 1996; Bacterial transferrin and lactoferrin receptors. Trends Microbiol 4:185–191
    [Google Scholar]
  17. Gribskov M., Burgess R. R., Devereux J. 1986; PEPPLOT, a protein secondary structure analysis program for the UWGCG sequence analysis software package. Nucleic Acids Res 14:327–334
    [Google Scholar]
  18. Griffiths E. 1999 Iron and Infection: Molecular, Physiological and Clinical Aspects , 2nd edn. Chichester: Wiley;
  19. Guzman L. M., Belin D., Carson M. J., Beckwith J. 1995; Tight regulation, modulation, and high-level expression by vectors containing the arabinose PBAD promoter. J Bacteriol 177:4121–4130
    [Google Scholar]
  20. Hantke K. 1981; Regulation of ferric iron transport in Escherichia coli K12: isolation of a constitutive mutant. Mol Gen Genet 182:288–292
    [Google Scholar]
  21. Henderson D. P., Payne S. M. 1994; Characterization of the Vibrio cholerae outer membrane heme transport protein HutA: sequence of the gene, regulation of expression, and homology to the family of TonB-dependent proteins. J Bacteriol 176:3269–3277
    [Google Scholar]
  22. Howard S. P., Herrmann C., Stratilo C. W., Braun V. 2001; In vivo synthesis of the periplasmic domain of TonB inhibits transport through the FecA and FhuA iron siderophore transporters of Escherichia coli . J Bacteriol 183:5885–5895
    [Google Scholar]
  23. Jeanteur D., Lakey J. H., Pattus F. 1991; The bacterial porin superfamily: sequence alignment and structure prediction. Mol Microbiol 5:2153–2164
    [Google Scholar]
  24. Johnston D. M., Cannon J. G. 1999; Construction of mutant strains of Neisseria gonorrhoeae lacking new antibiotic resistance markers using a two gene cassette with positive and negative selection. Gene 236:179–184
    [Google Scholar]
  25. Kellogg D. S., Peacock W. L., Deacon W. E., Brown L., Pirkle C. I. 1963; Neisseria gonorrhoeae . I. Virulence genetically linked to clonal variation. J Bacteriol 85:1274–1279
    [Google Scholar]
  26. Killmann H., Benz R., Braun V. 1996; Properties of the FhuA channel in the Escherichia coli outer membrane after deletion of FhuA portions within and outside the predicted gating loop. J Bacteriol 178:6913–6920
    [Google Scholar]
  27. Killmann H., Braun M., Herrmann C., Braun V. 2001; FhuA barrel-cork hybrids are active transporters and receptors. J Bacteriol 183:3476–3487
    [Google Scholar]
  28. Klebba P. E., Hofnung M., Charbit A. 1994; A model of maltodextrin transport through the sugar-specific porin, LamB, based on deletion analysis. EMBO J 13:4670–4675
    [Google Scholar]
  29. Koebnik R., Braun V. 1993; Insertion derivatives containing segments of up to 16 amino acids identify surface- and periplasm-exposed regions of the FhuA outer membrane receptor of Escherichia coli K-12. J Bacteriol 175:826–839
    [Google Scholar]
  30. Koebnik R., Locher K. P., Van Gelder P. 2000; Structure and function of bacterial outer membrane proteins: barrels in a nutshell. Mol Microbiol 37:239–253
    [Google Scholar]
  31. Lambert O., Moeck G. S., Levy D., Plancon L., Letellier L., Rigaud J. L. 1999; An 8-Å projected structure of FhuA, A “ligand-gated” channel of the Escherichia coli outer membrane. J Struct Biol 126:145–155
    [Google Scholar]
  32. Lathrop J. T., Wei B. Y., Touchie G. A., Kadner R. J. 1995; Sequences of the Escherichia coli BtuB protein essential for its insertion and function in the outer membrane. J Bacteriol 177:6810–6819
    [Google Scholar]
  33. Letoffe S., Ghigo J. M., Wandersman C. 1994; Iron acquisition from heme and hemoglobin by a Serratia marcescens extracellular protein. Proc Natl Acad Sci U S A 91:9876–9880
    [Google Scholar]
  34. Letoffe S., Redeker V., Wandersman C. 1998; Isolation and characterization of an extracellular haem-binding protein from Pseudomonas aeruginosa that shares function and sequence similarities with the Serratia marcescens HasA haemophore. Mol Microbiol 28:1223–1234
    [Google Scholar]
  35. Liu J., Rutz J. M., Feix J. B., Klebba P. E. 1993; Permeability properties of a large gated channel within the ferric enterobactin receptor, FepA. Proc Natl Acad Sci U S A 90:10653–10657
    [Google Scholar]
  36. Locher K. P., Rees B., Koebnik R., Mitschler A., Moulinier L., Rosenbusch J. P., Moras D. 1998; Transmembrane signaling across the ligand-gated FhuA receptor: crystal structures of free and ferrichrome-bound states reveal allosteric changes. Cell 95:771–778
    [Google Scholar]
  37. Newton S. M., Igo J. D., Scott D. C., Klebba P. E. 1999; Effect of loop deletions on the binding and transport of ferric enterobactin by FepA. Mol Microbiol 32:1153–1165
    [Google Scholar]
  38. Pettersson A., Klarenbeek V., van Deurzen J., Poolman J. T., Tommassen J. 1994; Molecular characterization of the structural gene for the lactoferrin receptor of the meningococcal strain H44/76. Microb Pathog 17:395–408
    [Google Scholar]
  39. Postle K. 1999; Active transport by customized beta-barrels. Nat Struct Biol 6:3–6
    [Google Scholar]
  40. Ratliff M., Zhu W., Deshmukh R., Wilks A., Stojiljkovic I. 2001; Homologues of neisserial heme oxygenase in gram-negative bacteria: degradation of heme by the product of the pigA gene of Pseudomonas aeruginosa . J Bacteriol 183:6394–6403
    [Google Scholar]
  41. Richardson A. R., Stojiljkovic I. 1999; HmbR, a hemoglobin-binding outer membrane protein of Neisseria meningitidis , undergoes phase variation. J Bacteriol 181:2067–2074
    [Google Scholar]
  42. Sambrook J., Fritsch E. F., Maniatis T. 1989 Molecular Cloning: a Laboratory Manual , 2nd edn. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
  43. Schirmer T., Cowan S. W. 1993; Prediction of membrane-spanning beta-strands and its application to maltoporin. Protein Sci 2:1361–1363
    [Google Scholar]
  44. Schryvers A. B., Stojiljkovic I. 1999; Iron acquisition systems in the pathogenic Neisseria . Mol Microbiol 32:1117–1123
    [Google Scholar]
  45. Schryvers A. B., Bonnah R., Yu R. H., Wong H., Retzer M. 1998; Bacterial lactoferrin receptors. Adv Exp Med Biol 443:123–133
    [Google Scholar]
  46. Scott D. C., Cao Z., Qi Z., Bauler M., Igo J. D., Newton S. M., Klebba P. E. 2001; Exchangeability of N termini in the ligand-gated porins of Escherichia coli . J Biol Chem 276:13025–13033
    [Google Scholar]
  47. Stojiljkovic I., Hantke K. 1992; Hemin uptake system of Yersinia enterocolitica : similarities with other TonB-dependent systems in gram-negative bacteria. EMBO J 11:4359–4367
    [Google Scholar]
  48. Stojiljkovic I., Hantke K. 1994; Transport of haemin across the cytoplasmic membrane through a haemin-specific periplasmic binding-protein-dependent transport system in Yersinia enterocolitica . Mol Microbiol 13:719–732
    [Google Scholar]
  49. Stojiljkovic I., Perkins-Balding D. 2002; Processing of heme and heme-containing proteins by bacteria. DNA Cell Biol 21:281–295
    [Google Scholar]
  50. Stojiljkovic I., Srinivasan N. 1997; Neisseria meningitidis tonB, exbB, and exbD genes: Ton-dependent utilization of protein-bound iron in Neisseriae . J Bacteriol 179:805–812
    [Google Scholar]
  51. Stojiljkovic I., Hwa V., de Saint Martin L., O'Gaora P., Nassif X., Heffron F., So M. 1995; The Neisseria meningitidis haemoglobin receptor: its role in iron utilization and virulence. Mol Microbiol 15:531–541
    [Google Scholar]
  52. Stojiljkovic I., Larson J., Hwa V., Anic S., So M. 1996; HmbR outer membrane receptors of pathogenic Neisseria spp. iron-regulated, hemoglobin-binding proteins with a high level of primary structure conservation. J Bacteriol 178:4670–4678
    [Google Scholar]
  53. Urushibara N., Kumazaki T., Ishii S. 1992; Hemoglobin-binding site on human haptoglobin. Identification of lysyl residues participating in the binding. J Biol Chem 267:13413–13417
    [Google Scholar]
  54. Usher K. C., Ozkan E., Gardner K. H., Deisenhofer J. 2001; The plug domain of FepA, a TonB-dependent transport protein from Escherichia coli , binds its siderophore in the absence of the transmembrane barrel domain. Proc Natl Acad Sci U S A 98:10676–10681
    [Google Scholar]
  55. Vakharia H. L., Postle K. 2002; FepA with globular domain deletions lacks activity. J Bacteriol 184:5508–5512
    [Google Scholar]
  56. Van Der Helm D., Chakraborty R., Ferguson A. D., Smith B. S., Esser L., Deisenhofer J. 2002; Bipartite gating in the outer membrane protein FecA. Biochem Soc Trans 30:708–710
    [Google Scholar]
  57. Wandersman C., Stojiljkovic I. 2000; Bacterial heme sources: the role of heme, hemoprotein receptors and hemophores. Curr Opin Microbiol 3:215–220
    [Google Scholar]
  58. Wang R. F., Kushner S. R. 1991; Construction of versatile low-copy-number vectors for cloning, sequencing and gene expression in Escherichia coli . Gene 100:195–199
    [Google Scholar]
  59. Winkelmann G. 2002; Microbial siderophore-mediated transport. Biochem Soc Trans 30:691–696
    [Google Scholar]
  60. Zhu W., Wilks A., Stojiljkovic I. 2000a; Degradation of heme in gram-negative bacteria: the product of the hemO gene of Neisseriae is a heme oxygenase. J Bacteriol 182:6783–6790
    [Google Scholar]
  61. Zhu W., Hunt D. J., Richardson A. R., Stojiljkovic I. 2000b; Use of heme compounds as iron sources by pathogenic neisseriae requires the product of the hemO gene. J Bacteriol 182:439–447
    [Google Scholar]
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