1887

Abstract

The M-protein genes of isolated from 17 outwardly healthy horses after 4 strangles outbreaks had ended, including a quarantined animal, were compared with those of isolates from 167 active cases of strangles across 4 countries. The healthy horses included 16 persistent carriers, at least one from each of the four outbreaks. These carriers, despite being outwardly healthy, had empyema of the guttural pouch(es), an enlargement of the equine Eustachian tube. A persistent carrier from two of these outbreaks, the quarantined animal and a healthy animal with normal guttural pouches, from which was isolated only once, were colonized by variant with truncated M-protein genes (24% of outwardly healthy animals with ). The truncated M-protein genes had in-frame deletions in slightly different positions between the signal sequence and the central repeat region, equivalent to approximately 20% of the mature expressed protein. Immunoblotting with antibody to recombinant M-protein confirmed that the variants expressed a truncated form of the M-protein. In contrast to the outwardly healthy carriers, only 1/167 of isolates from strangles cases possessed a truncated M-protein gene (<1%; Fisher’s exact test, =00002). Compared with isolates from healthy horses with a truncated M-protein, much more of the N terminus of the truncated M-protein was retained in the variant from a strangles case. Variant from outwardly healthy animals were more susceptible to phagocytosis by neutrophils than typical isolates. This is the first report of detection of with a truncated M-protein. The distribution of the variants between strangles cases and carriers suggests that the 80% of the M-protein retained in the variants may contribute to colonization whilst the deleted portion of the gene may be needed for full virulence.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-146-6-1361
2000-06-01
2019-12-05
Loading full text...

Full text loading...

/deliver/fulltext/micro/146/6/1461361a.html?itemId=/content/journal/micro/10.1099/00221287-146-6-1361&mimeType=html&fmt=ahah

References

  1. Chanter, N., Collin, N. C. & Mumford, J. A. (1994). Resistance of Streptococcus equi in vitro to equine polymorphonuclear leucocytes. In Equine Infectious Diseases VII: Proceedings of the Seventh International Conference, Tokyo, Japan, 8th–11th June 1994, pp. 201–210. Edited by H. Nakajima & W. Plowright. Newmarket: R & W Publications.
  2. Chanter, N., Collin, N., Holmes, N., Binns, M. & Mumford, J. ( 1997; ). Characterization of the Lancefield group C streptococcus 16S–23S RNA gene intergenic spacer and its potential for identification and sub-specific typing. Epidemiol Infect 118, 125-135.[CrossRef]
    [Google Scholar]
  3. Collin, N. C., Chanter, N. & Mumford, J. A. ( 1999; ). Detection and characterisation of Streptococcus equi and Streptococcus zooepidemicus proteases to identify potential protective immunogens. In Equine Infectious Diseases VIII: Proceedings of the Eighth International Conference, Dubai, United Arab Emirates, 23rd–26th March 1998, pp. 535-537. Edited by U. Wernery, J. F. Wade, J. A. Mumford & O. R. Kaaden. Newmarket: R & W Publications.
  4. Fischetti, V. A. ( 1991; ). Streptococcal M protein. Sci Am 264, 58-65.
    [Google Scholar]
  5. Fischetti, V. A., Jarymowycz, M., Jones, K. F. & Scott, J. R. ( 1986; ). Streptococcal M protein size mutants occur at high frequency within a single strain. J Exp Med 164, 971-980.[CrossRef]
    [Google Scholar]
  6. Galan, J. E. & Timoney, J. F. ( 1988; ). Immunologic and genetic comparison of Streptococcus equi isolates from the United States and Europe. J Clin Microbiol 26, 1142-1146.
    [Google Scholar]
  7. Grant, S. T., Efstratiou, A. & Chanter, N. ( 1993; ). Laboratory diagnosis of strangles and the isolation of atypical Streptococcus equi. Vet Rec 133, 215-216.[CrossRef]
    [Google Scholar]
  8. Harbaugh, M. P., Podbielski, A., Hugl, S. & Cleary, P. P. ( 1993; ). Nucleotide substitutions and small-scale insertion produce size and antigenic variation in group A streptococcal M1 protein. Mol Microbiol 8, 981-991.[CrossRef]
    [Google Scholar]
  9. Kehoe, M. A., Kapur, V., Whatmore, A. M. & Musser, J. M. ( 1996; ). Horizontal gene transfer among group A streptococci: implications for pathogenesis and epidemiology. Trends Microbiol 4, 436-443.[CrossRef]
    [Google Scholar]
  10. Meehan, M., Nowlan, P. & Owen, P. ( 1998; ). Affinity purification and characterization of a fibrinogen-binding protein complex which protects mice against lethal challenge with Streptococcus equi subsp. equi. Microbiology 144, 993-1003.[CrossRef]
    [Google Scholar]
  11. Meehan, M., Nowlan, P. & Owen, P. (1999). Localisation of the ligand binding domain in the fibrinogen-binding protein complex which protects mice against lethal challenge with Streptococcus equi subsp. equi. Abstracts of the 142nd Ordinary Meeting of The Society for General Microbiology, p. 62.
  12. Newton, J. R., Wood, J. L. N., Dunn, K. A., DeBrauwere, M. N. & Chanter, N. ( 1997; ). Naturally occurring persistent and asymptomatic infection of the guttural pouches of horses with Streptococcus equi. Vet Rec 140, 84-90.[CrossRef]
    [Google Scholar]
  13. Newton, J. R., Verheyen, K., Talbot, N. C., Timoney, J. F., Lakhani, K., Wood, J. L. N. & Chanter, N. (2000). Control of strangles outbreaks by isolation of guttural pouch carriers identified using PCR and culture of Streptococcus equi. Equine Vet J (in press).
  14. Timoney, J. F. & Eggers, D. ( 1985; ). Serum bactericidal responses to Streptococcus equi of horses following infection or vaccination. Equine Vet J 17, 306-310.[CrossRef]
    [Google Scholar]
  15. Timoney, J. F. & Mukhtar, M. M. ( 1993; ). The protective M proteins of the equine group C streptococci. Vet Microbiol 37, 389-395.[CrossRef]
    [Google Scholar]
  16. Timoney, J. F., Artiushin, S. C. & Boschwitz, J. S. ( 1997; ). Comparison of the sequences and functions of Streptococcus equi M-like proteins SeM and SzPSe. Infect Immun 65, 3600-3605.
    [Google Scholar]
  17. Timoney, J. F., Artiushin, S. & Wang, J. ( 1999; ). Regions of the protective M-like protein of Streptococcus equi recognised by serum and mucosal antibodies of convalescent horses. In Equine Infectious Diseases VIII: Proceedings of the Eighth International Conference, Dubai, United Arab Emirates, 23rd–26th March 1998, pp. 88-94. Edited by U. Wernery, J. F. Wade, J. A. Mumford & O. R. Kaaden. Newmarket: R & W Publications.
  18. Towbin, H., Staehelin, T. & Gordon, J. ( 1979; ). Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci USA 76, 4350-4354.[CrossRef]
    [Google Scholar]
  19. Whatmore, A. M., Kapur, V., Sullivan, D. J., Musser, J. M. & Kehoe, M. A. ( 1994; ). Non-congruent relationships between variation in emm gene sequences and the population genetic structure of group A streptococci. Mol Microbiol 14, 619-631.[CrossRef]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-146-6-1361
Loading
/content/journal/micro/10.1099/00221287-146-6-1361
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