1887

Abstract

The role of phase variation of , and in the ability of type b to colonize the nasopharynx, bloodstream and cerebrospinal fluid (CSF) of infants was investigated. This was achieved by using PCR to determine the number of 5′-CAAT-3′ repeats present in each gene, which is indicative of whether each ORF can be expressed. Multiple PCR products of different intensities were amplified from all three genes at each site sampled. This indicated that the nasopharynx, bloodstream and CSF were colonized by a heterogeneous population of organisms, expressing different combinations of genes. At each site however, a predominant PCR product was amplified from each gene, indicating that organisms with this genotype were the most abundant. The number of 5′-CAAT-3′ repeats in this predominant product varied depending upon whether organisms were isolated from the nasopharynx, bloodstream or CSF. These observations suggest that the expression of different combinations of genes may influence the efficiency with which colonizes the nasopharynx, bloodstream and CSF of infant rats.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-145-11-3005
1999-11-01
2024-10-13
Loading full text...

Full text loading...

/deliver/fulltext/micro/145/11/1453005a.html?itemId=/content/journal/micro/10.1099/00221287-145-11-3005&mimeType=html&fmt=ahah

References

  1. Alexander H. E. 1965; The Haemophilus group. In Bacterial and Mycotic Infections of Man pp. 724–741Edited by Dubos R. H., Hirsch J. G. London: Pitman Medical Publishing;
    [Google Scholar]
  2. Anderson P., Flesher A., Shaw S., Harding L., Smith D. H. 1980; Phenotypic and genetic variation in the susceptibility to Haemophilus influenzae type b to antibodies to somatic antigens. J Clin Invest 65:885–891 [CrossRef]
    [Google Scholar]
  3. Cope L. D., Jogev R., Mertsola J., Latimer J. L., Hanson M. S., McCracken G. H., Hansen E. J. 1991; Molecular cloning of a gene involved in lipooligosaccharide biosynthesis and virulence expression by Haemophilus influenzae type b. Mol Microbiol 5:1113–1124 [CrossRef]
    [Google Scholar]
  4. High N. J., Deadman M. E., Moxon E. R. 1993; The role of a repetitive DNA motif (5′-CAAT-3′) in the variable expression of the Haemophilus influenzae lipopolysaccharide epitope Galα(1–4)βGal. Mol Microbiol 9:1275–1282 [CrossRef]
    [Google Scholar]
  5. Hood D. W., Deadman M. E., Jennings M. P., Bisercic M., Fleischmann R. D., Venter J. C., Moxon E. R. 1996; DNA repeats identify novel virulence genes in Haemophilus influenzae. Proc Natl Acad Sci USA 93:11121–11125 [CrossRef]
    [Google Scholar]
  6. Jarosik G. P., Hansen E. J. 1994; Identification of a new locus involved in the expression of Haemophilus influenzae type b lipooligosaccharide. Infect Immun 62:4861–4867
    [Google Scholar]
  7. Kimura A., Hansen E. J. 1986; Antigenic and phenotypic variants of Haemophilus influenzae type b lipopolysaccharide and their relationship to virulence. Infect Immun 51:60–79
    [Google Scholar]
  8. Levinson G., Gutman G. A. 1987; High frequencies of short frameshifts in poly-CA/TG tandem repeats borne by bacteriophage M13 in Escherichia coli K-12. Nucleic Acids Res 15:5323–5338 [CrossRef]
    [Google Scholar]
  9. Maskell D. J., Szabo M. J., Butler P. D., Williams A. E., Moxon E. R. 1992; Molecular analysis of a complex locus from Haemophilus influenzae involved in phase-variable lipopolysaccharide biosynthesis. Mol Microbiol 5:1013–1022
    [Google Scholar]
  10. Moxon E. R. 1985; Haemophilus influenzae. In Principles and Practice of Infectious Disease pp. 1274–1279Edited by Mandrell G., Douglas R., Bennet J. New York: Wiley;
    [Google Scholar]
  11. Moxon E. R., Smith A. L., Averill D. R., Smith D. H. 1974; Haemophilus influenzae meningitis in infant rats after intranasal inoculation. J Infect Dis 129:154–162 [CrossRef]
    [Google Scholar]
  12. Smith A. L., Smith D. H., Averill D. R., Moxon E. R. 1973; Production of Haemophilus influenzae type B meningitis in infant rats by intraperitoneal inoculation. Infect Immun 8:278–290
    [Google Scholar]
  13. Weiser J. N., Love J., Moxon E. R. 1989; The molecular mechanism of phase-variation in Haemophilus influenzae lipopolysaccharide. Cell 59:657–665 [CrossRef]
    [Google Scholar]
  14. Weiser J. N., Maskell D. J., Butler P. D., Moxon E. R. 1990; Characterisation of repetitive sequences controlling phase variation of Haemophilus influenzae lipopolysaccharide. J Bacteriol 172:3304–3309
    [Google Scholar]
  15. Weiser J. N., Shchepetov M., Chong S. T. 1997; Decoration of lipopolysaccharide with phosphorylcholine: a phase-variable characteristic of Haemophilus influenzae. Infect Immun 65:943–950
    [Google Scholar]
  16. Weiser J. N., Pan N., McGowan K. L., Musher D., Martin A., Richards J. 1998; Phosphorylcholine on the lipopolysaccharide of Haemophilus influenzae contributes to persistence in the respiratory tract and sensitivity to serum killing mediated by C-reactive protein. J Exp Med 187:631–640 [CrossRef]
    [Google Scholar]
  17. Whittle H. C., Greenwood B. M. 1977; Cerebrospinal fluid immunoglobulins and complement in meningococcal meningitis. J Clin Pathol 31:213–216
    [Google Scholar]
  18. Zwahlen A., Nydegger U. E., Vaudaux P., Lambert P.-H., Waldvogel F. A. 1982; Complement-mediated opsonic activity in normal and infected human cerebrospinal fluid: early response during bacterial meningitis. J Infect Dis 145:635–646 [CrossRef]
    [Google Scholar]
/content/journal/micro/10.1099/00221287-145-11-3005
Loading
/content/journal/micro/10.1099/00221287-145-11-3005
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error