FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
PloS one2018; 13(10); e0204475; doi: 10.1371/journal.pone.0204475

Identification of a VapA virulence factor functional homolog in Rhodococcus equi isolates housing the pVAPB plasmid.

Abstract: Rhodococcus equi is a facultative intracellular bacterium of macrophages and is an important pathogen of animals and immunocompromised people wherein disease results in abcessation of the lungs and other sites. Prior work has shown that the presence of the major virulence determinant, VapA, encoded on the pVAPA-type plasmid, disrupts normal phagosome development and is essential for bacterial replication within macrophages. pVAPA- type plasmids are typical of R. equi strains derived from foals while strains from pigs carry plasmids of the pVAPB-type, lacking vapA, and those from humans harbor various types of plasmids including pVAPA and pVAPB. Through the creation and analysis of a series of gene deletion mutants, we found that vapK1 or vapK2 is required for optimal intracellular replication of an R. equi isolate carrying a pVAPB plasmid type. Complementation analysis of a ΔvapA R. equi strain with vapK1 or vapK2 showed the VapK proteins of the pVAPB-type plasmid could restore replication capacity to the macrophage growth-attenuated ΔvapA strain. Additionally, in contrast to the intracellular growth capabilities displayed by an equine R. equi transconjugant strain carrying a pVAPB-type plasmid, a transconjugant strain carrying a pVAPB-type plasmid deleted of vapK1 and vapK2 proved incapable of replication in equine macrophages. Cumulatively, these data indicate that VapK1 and K2 are functionally equivalent to VapA.
Get Full Text
Publication Date: 2018-10-04 PubMed ID: 30286098PubMed Central: PMC6171844DOI: 10.1371/journal.pone.0204475Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article focuses on the bacterium Rhodococcus equi, a pathogen in animals and immunocompromised individuals causing lung abscesses, and the role of a key viral factor, VapA. This study discovered an equivalent viral factor, VapK1 and VapK2, in versions of R. equi that affect pigs and humans, suggesting functional homology.

Introduction and Background Information

  • Rhodococcus equi is a bacterium that primarily affects macrophages (immune cells) in animals and people with weak immune systems.
  • For this bacterium to effectively grow and replicate within hosts, it relies on a chief virulence, or severity factor, known as VapA, which is found on a specific type of plasmid (genetic material) known as pVAPA.
  • R. equi strains differ in animals and humans, with porcine (pig) strains carrying the pVAPB-type plasmid and human strains housing various types of plasmids, including pVAPA and pVAPB. The pVAPB plasmid does not contain the vapA gene.

Research Process and Findings

  • The researchers constructed and analyzed a series of gene deletion mutants in order to identify key genes required for optimal replication of R. equi with a pVAPB plasmid.
  • It was found that the genes vapK1 or vapK2 were necessary to the process. When either of these genes were added to an R.equi strain without VapA, replication capacity was restored, suggesting they were functionally equivalent to VapA.
  • Furthermore, it was observed that an R. equi strain that can typically grow within cells, when carrying a pVAPB-type plasmid, was unable to replicate in horse macrophages when vapK1 and vapK2 were removed.

Conclusion

  • The research concluded that VapK1 and VapK2 functioned in a manner similar to VapA. This discovery suggests that VapK1 and VapK2 might be critical virulence factor in R. equi infections in pigs and humans.
  • Understanding the role of these key virulence factors could potentially help in developing better treatments or preventive measures against R. equi infections.

Cite This Article

APA
Willingham-Lane JM, Coulson GB, Hondalus MK. (2018). Identification of a VapA virulence factor functional homolog in Rhodococcus equi isolates housing the pVAPB plasmid. PLoS One, 13(10), e0204475. https://doi.org/10.1371/journal.pone.0204475

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 13
Issue: 10
Pages: e0204475
PII: e0204475

Researcher Affiliations

Willingham-Lane, Jennifer M
  • Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America.
Coulson, Garry B
  • Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America.
Hondalus, Mary K
  • Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America.

MeSH Terms

  • Actinomycetales Infections / microbiology
  • Actinomycetales Infections / veterinary
  • Animals
  • Bacterial Proteins / genetics
  • Cells, Cultured
  • Female
  • Horse Diseases / microbiology
  • Horses
  • Macrophages / microbiology
  • Mice, Inbred BALB C
  • Mutation
  • Plasmids
  • Rhodococcus equi / genetics
  • Rhodococcus equi / growth & development
  • Rhodococcus equi / isolation & purification
  • Rhodococcus equi / pathogenicity
  • Virulence Factors / genetics

Conflict of Interest Statement

The authors have declared that no competing interests exist.

References

This article includes 36 references
  1. Barton MD, Hughes KL. Ecology of Rhodococcus equi.. Vet Microbiol 1984 Feb;9(1):65-76.
    pubmed: 6719819doi: 10.1016/0378-1135(84)90079-8google scholar: lookup
  2. Prescott JF. Rhodococcus equi: an animal and human pathogen.. Clin Microbiol Rev 1991 Jan;4(1):20-34.
    pmc: PMC358176pubmed: 2004346doi: 10.1128/CMR.4.1.20google scholar: lookup
  3. Yager JA. The pathogenesis of Rhodococcus equi pneumonia in foals.. Vet Microbiol 1987 Aug;14(3):225-32.
    pubmed: 3314108doi: 10.1016/0378-1135(87)90109-xgoogle scholar: lookup
  4. Golub B, Falk G, Spink WW. Lung abscess due to Corynebacterium equi. Report of first human infection.. Ann Intern Med 1967 Jun;66(6):1174-7.
    pubmed: 6067513doi: 10.7326/0003-4819-66-6-1174google scholar: lookup
  5. Takai S, Takeuchi T, Tsubaki S. Isolation of Rhodococcus (Corynebacterium) equi and atypical mycobacteria from the lymph nodes of healthy pigs.. Nihon Juigaku Zasshi 1986 Apr;48(2):445-8.
    pubmed: 3712907doi: 10.1292/jvms1939.48.445google scholar: lookup
  6. Takai S, Fukunaga N, Ochiai S, Imai Y, Sasaki Y, Tsubaki S, Sekizaki T. Identification of intermediately virulent Rhodococcus equi isolates from pigs.. J Clin Microbiol 1996 Apr;34(4):1034-7.
    pmc: PMC228949pubmed: 8815079doi: 10.1128/jcm.34.4.1034-1037.1996google scholar: lookup
  7. Madarame H, Matsuda H, Okada M, Yoshida S, Sasaki Y, Tsubaki S, Hasegawa Y, Takai S. Cutaneous malakoplakia in pigs inoculated with Rhodococcus equi.. FEMS Immunol Med Microbiol 1998 Dec;22(4):329-33.
    pubmed: 9879924doi: 10.1111/j.1574-695X.1998.tb01222.xgoogle scholar: lookup
  8. Flynn O, Quigley F, Costello E, O'Grady D, Gogarty A, Mc Guirk J, Takai S. Virulence-associated protein characterisation of Rhodococcus equi isolated from bovine lymph nodes.. Vet Microbiol 2001 Feb 12;78(3):221-8.
    pubmed: 11165066doi: 10.1016/s0378-1135(00)00297-2google scholar: lookup
  9. Letek M, Ocampo-Sosa AA, Sanders M, Fogarty U, Buckley T, Leadon DP, González P, Scortti M, Meijer WG, Parkhill J, Bentley S, Vázquez-Boland JA. Evolution of the Rhodococcus equi vap pathogenicity island seen through comparison of host-associated vapA and vapB virulence plasmids.. J Bacteriol 2008 Sep;190(17):5797-805.
    doi: 10.1128/JB.00468-08pmc: PMC2519538pubmed: 18606735google scholar: lookup
  10. Valero-Rello A, Hapeshi A, Anastasi E, Alvarez S, Scortti M, Meijer WG, MacArthur I, Vázquez-Boland JA. An Invertron-Like Linear Plasmid Mediates Intracellular Survival and Virulence in Bovine Isolates of Rhodococcus equi.. Infect Immun 2015 Jul;83(7):2725-37.
    doi: 10.1128/IAI.00376-15pmc: PMC4468562pubmed: 25895973google scholar: lookup
  11. Takai S, Hines SA, Sekizaki T, Nicholson VM, Alperin DA, Osaki M, Takamatsu D, Nakamura M, Suzuki K, Ogino N, Kakuda T, Dan H, Prescott JF. DNA sequence and comparison of virulence plasmids from Rhodococcus equi ATCC 33701 and 103.. Infect Immun 2000 Dec;68(12):6840-7.
    pmc: PMC97788pubmed: 11083803doi: 10.1128/IAI.68.12.6840-6847.2000google scholar: lookup
  12. Hondalus MK, Mosser DM. Survival and replication of Rhodococcus equi in macrophages.. Infect Immun 1994 Oct;62(10):4167-75.
    pmc: PMC303092pubmed: 7927672doi: 10.1128/iai.62.10.4167-4175.1994google scholar: lookup
  13. Giguère S, Hondalus MK, Yager JA, Darrah P, Mosser DM, Prescott JF. Role of the 85-kilobase plasmid and plasmid-encoded virulence-associated protein A in intracellular survival and virulence of Rhodococcus equi.. Infect Immun 1999 Jul;67(7):3548-57.
    pmc: PMC116543pubmed: 10377138doi: 10.1128/IAI.67.7.3548-3557.1999google scholar: lookup
  14. Jain S, Bloom BR, Hondalus MK. Deletion of vapA encoding Virulence Associated Protein A attenuates the intracellular actinomycete Rhodococcus equi.. Mol Microbiol 2003 Oct;50(1):115-28.
    pubmed: 14507368doi: 10.1046/j.1365-2958.2003.03689.xgoogle scholar: lookup
  15. Coulson GB, Miranda-CasoLuengo AA, Miranda-CasoLuengo R, Wang X, Oliver J, Willingham-Lane JM, Meijer WG, Hondalus MK. Transcriptome reprogramming by plasmid-encoded transcriptional regulators is required for host niche adaption of a macrophage pathogen.. Infect Immun 2015 Aug;83(8):3137-45.
    doi: 10.1128/IAI.00230-15pmc: PMC4496601pubmed: 26015480google scholar: lookup
  16. Wright LM, Carpinone EM, Bennett TL, Hondalus MK, Starai VJ. VapA of Rhodococcus equi binds phosphatidic acid.. Mol Microbiol 2018 Feb;107(3):428-444.
    doi: 10.1111/mmi.13892pmc: PMC5777868pubmed: 29205554google scholar: lookup
  17. von Bargen K, Polidori M, Becken U, Huth G, Prescott JF, Haas A. Rhodococcus equi virulence-associated protein A is required for diversion of phagosome biogenesis but not for cytotoxicity.. Infect Immun 2009 Dec;77(12):5676-81.
    doi: 10.1128/IAI.00856-09pmc: PMC2786453pubmed: 19797071google scholar: lookup
  18. Toyooka K, Takai S, Kirikae T. Rhodococcus equi can survive a phagolysosomal environment in macrophages by suppressing acidification of the phagolysosome.. J Med Microbiol 2005 Nov;54(Pt 11):1007-1015.
    doi: 10.1099/jmm.0.46086-0pubmed: 16192430google scholar: lookup
  19. Fernandez-Mora E, Polidori M, Lührmann A, Schaible UE, Haas A. Maturation of Rhodococcus equi-containing vacuoles is arrested after completion of the early endosome stage.. Traffic 2005 Aug;6(8):635-53.
    doi: 10.1111/j.1600-0854.2005.00304.xpubmed: 15998320google scholar: lookup
  20. Willingham-Lane JM, Berghaus LJ, Giguère S, Hondalus MK. Influence of Plasmid Type on the Replication of Rhodococcus equi in Host Macrophages.. mSphere 2016 Sep-Oct;1(5).
    pmc: PMC5061997pubmed: 27747295doi: 10.1128/mSphere.00186-16google scholar: lookup
  21. van der Geize R, de Jong W, Hessels GI, Grommen AW, Jacobs AA, Dijkhuizen L. A novel method to generate unmarked gene deletions in the intracellular pathogen Rhodococcus equi using 5-fluorocytosine conditional lethality.. Nucleic Acids Res 2008 Dec;36(22):e151.
    doi: 10.1093/nar/gkn811pmc: PMC2602762pubmed: 18984616google scholar: lookup
  22. Stover CK, de la Cruz VF, Fuerst TR, Burlein JE, Benson LA, Bennett LT, Bansal GP, Young JF, Lee MH, Hatfull GF. New use of BCG for recombinant vaccines.. Nature 1991 Jun 6;351(6326):456-60.
    doi: 10.1038/351456a0pubmed: 1904554google scholar: lookup
  23. Tripathi VN, Harding WC, Willingham-Lane JM, Hondalus MK. Conjugal transfer of a virulence plasmid in the opportunistic intracellular actinomycete Rhodococcus equi.. J Bacteriol 2012 Dec;194(24):6790-801.
    doi: 10.1128/JB.01210-12pmc: PMC3510604pubmed: 23042997google scholar: lookup
  24. Coulson GB, Agarwal S, Hondalus MK. Characterization of the role of the pathogenicity island and vapG in the virulence of the intracellular actinomycete pathogen Rhodococcus equi.. Infect Immun 2010 Aug;78(8):3323-34.
    doi: 10.1128/IAI.00081-10pmc: PMC2916281pubmed: 20439471google scholar: lookup
  25. Takai S, Koike K, Ohbushi S, Izumi C, Tsubaki S. Identification of 15- to 17-kilodalton antigens associated with virulent Rhodococcus equi.. J Clin Microbiol 1991 Mar;29(3):439-43.
    pmc: PMC269796pubmed: 2037660doi: 10.1128/jcm.29.3.439-443.1991google scholar: lookup
  26. Takai S, Watanabe Y, Ikeda T, Ozawa T, Matsukura S, Tamada Y, Tsubaki S, Sekizaki T. Virulence-associated plasmids in Rhodococcus equi.. J Clin Microbiol 1993 Jul;31(7):1726-9.
    pmc: PMC265621pubmed: 8349748doi: 10.1128/jcm.31.7.1726-1729.1993google scholar: lookup
  27. Takai S, Madarame H, Matsumoto C, Inoue M, Sasaki Y, Hasegawa Y, Tsubaki S, Nakane A. Pathogenesis of Rhodococcus equi infection in mice: roles of virulence plasmids and granulomagenic activity of bacteria.. FEMS Immunol Med Microbiol 1995 Jun;11(3):181-90.
    pubmed: 7581269doi: 10.1111/j.1574-695X.1995.tb00115.xgoogle scholar: lookup
  28. Johnson JA, Prescott JF, Markham RJ. The pathology of experimental Corynebacterium equi infection in foals following intrabronchial challenge.. Vet Pathol 1983 Jul;20(4):440-9.
    doi: 10.1177/030098588302000407pubmed: 6623848google scholar: lookup
  29. Tkachuk-Saad O, Prescott J. Rhodococcus equi plasmids: isolation and partial characterization.. J Clin Microbiol 1991 Dec;29(12):2696-700.
    pmc: PMC270416pubmed: 1757535doi: 10.1128/jcm.29.12.2696-2700.1991google scholar: lookup
  30. Okoko T, Blagova EV, Whittingham JL, Dover LG, Wilkinson AJ. Structural characterisation of the virulence-associated protein VapG from the horse pathogen Rhodococcus equi.. Vet Microbiol 2015 Aug 31;179(1-2):42-52.
    doi: 10.1016/j.vetmic.2015.01.027pmc: PMC4518536pubmed: 25746683google scholar: lookup
  31. Whittingham JL, Blagova EV, Finn CE, Luo H, Miranda-CasoLuengo R, Turkenburg JP, Leech AP, Walton PH, Murzin AG, Meijer WG, Wilkinson AJ. Structure of the virulence-associated protein VapD from the intracellular pathogen Rhodococcus equi.. Acta Crystallogr D Biol Crystallogr 2014 Aug;70(Pt 8):2139-51.
    doi: 10.1107/S1399004714012632pmc: PMC4118825pubmed: 25084333google scholar: lookup
  32. Geerds C, Wohlmann J, Haas A, Niemann HH. Structure of Rhodococcus equi virulence-associated protein B (VapB) reveals an eight-stranded antiparallel β-barrel consisting of two Greek-key motifs.. Acta Crystallogr F Struct Biol Commun 2014 Jul;70(Pt 7):866-71.
    doi: 10.1107/S2053230X14009911pmc: PMC4089522pubmed: 25005079google scholar: lookup
  33. Takai S, Iie M, Watanabe Y, Tsubaki S, Sekizaki T. Virulence-associated 15- to 17-kilodalton antigens in Rhodococcus equi: temperature-dependent expression and location of the antigens.. Infect Immun 1992 Jul;60(7):2995-7.
    pmc: PMC257265pubmed: 1612765doi: 10.1128/iai.60.7.2995-2997.1992google scholar: lookup
  34. Lührmann A, Mauder N, Sydor T, Fernandez-Mora E, Schulze-Luehrmann J, Takai S, Haas A. Necrotic death of Rhodococcus equi-infected macrophages is regulated by virulence-associated plasmids.. Infect Immun 2004 Feb;72(2):853-62.
    doi: 10.1128/IAI.72.2.853-862.2004pmc: PMC321572pubmed: 14742529google scholar: lookup
  35. Andersson DI, Hughes D. Gene amplification and adaptive evolution in bacteria.. Annu Rev Genet 2009;43:167-95.
    doi: 10.1146/annurev-genet-102108-134805pubmed: 19686082google scholar: lookup
  36. Treangen TJ, Rocha EP. Horizontal transfer, not duplication, drives the expansion of protein families in prokaryotes.. PLoS Genet 2011 Jan 27;7(1):e1001284.
    doi: 10.1371/journal.pgen.1001284pmc: PMC3029252pubmed: 21298028google scholar: lookup

Citations

This article has been cited 6 times.
  1. Hansen P, Haubenthal T, Reiter C, Kniewel J, Bosse-Plois K, Niemann HH, von Bargen K, Haas A. Differential Effects of Rhodococcus equi Virulence-Associated Proteins on Macrophages and Artificial Lipid Membranes. Microbiol Spectr 2023 Feb 14;11(2):e0341722.
    doi: 10.1128/spectrum.03417-22pubmed: 36786596google scholar: lookup
  2. Ivshina IB, Kuyukina MS, Krivoruchko AV, Tyumina EA. Responses to Ecopollutants and Pathogenization Risks of Saprotrophic Rhodococcus Species. Pathogens 2021 Aug 2;10(8).
    doi: 10.3390/pathogens10080974pubmed: 34451438google scholar: lookup
  3. Geerds C, Haas A, Niemann HH. Conformational changes of loops highlight a potential binding site in Rhodococcus equi VapB. Acta Crystallogr F Struct Biol Commun 2021 Aug 1;77(Pt 8):246-253.
    doi: 10.1107/S2053230X2100738Xpubmed: 34341190google scholar: lookup
  4. Vázquez-Boland JA, Meijer WG. The pathogenic actinobacterium Rhodococcus equi: what's in a name?. Mol Microbiol 2019 Jul;112(1):1-15.
    doi: 10.1111/mmi.14267pubmed: 31099908google scholar: lookup
  5. Yerlikaya Z, Miranda-CasoLuengo R, Yin Y, Cheng C, Meijer WG. Clade-1 Vap virulence proteins of Rhodococcus equi are associated with the cell surface and support intracellular growth in macrophages. PLoS One 2025;20(1):e0316541.
    doi: 10.1371/journal.pone.0316541pubmed: 39761314google scholar: lookup
  6. da Silveira BP, Cohen ND, Lawhon SD, Watson RO, Bordin AI. Protective immune response against Rhodococcus equi: An innate immunity-focused review. Equine Vet J 2025 May;57(3):563-586.
    doi: 10.1111/evj.14214pubmed: 39258739google scholar: lookup
Subscribe to our newsletter
Join 99,727 horse owners like you who receive our email updates on horse health and nutrition.