Analyze Diet
Applied and environmental microbiology2019; 85(7); e02665-18; doi: 10.1128/AEM.02665-18

Effect of Macrolide and Rifampin Resistance on the Fitness of Rhodococcus equi.

Abstract: is a leading cause of severe pneumonia in foals. Standard treatment is dual antimicrobial therapy with a macrolide and rifampin, but the emergence of macrolide- and rifampin-resistant isolates is an increasing problem. The objective of this study was to determine the effect of macrolide and/or rifampin resistance on fitness of Three unique isogenic sets were created, each consisting of four strains, as follows: a susceptible parent isolate, strains resistant to macrolides or rifampin, and a dual macrolide- and rifampin-resistant strain. Each isogenic set's bacterial growth curve was generated in enriched medium, minimal medium (MM), and minimal medium without iron (MM-I). Bacterial survival in soil was analyzed over 12 months at -20°C, 4°C, 25°C, and 37°C, and the ability of these strains to retain antimicrobial resistance during sequential subculturing was determined. Insertion of the mobile element conferring macrolide resistance had minimal effect on growth. However, two of three mutations conferring rifampin resistance resulted in a decreased growth rate in MM. In soil, macrolide- or rifampin-resistant strains exhibited limited growth compared to that of the susceptible isolate at all temperatures except -20°C. During subculturing, macrolide resistance was lost over time, and two of three mutations reverted to the wild-type form. The growth of rifampin-resistant colonies is delayed under nutrient restriction. In soil, possession of rifampin or macrolide resistance results in decreased fitness. Both macrolide and rifampin resistance can be lost after repeated subculturing. This work advances our understanding of the opportunistic environmental pathogen , a disease agent affecting horses and immunocompromised people. is one of the most common causes of severe pneumonia in young horses. For decades, the standard treatment for pneumonia in horses has been dual antimicrobial therapy with a macrolide and rifampin; effective alternatives to this combination are lacking. The World Health Organization classifies these antimicrobial agents as critically important for human medicine. Widespread macrolide and rifampin resistance in isolates is a major emerging problem for the horse-breeding industry and might also adversely impact human health if resistant strains infect people or transfer resistance mechanisms to other pathogens. This study details the impact of antimicrobial resistance on fitness, a vital step for understanding the ecology and epidemiology of resistant isolates, and will support development of novel strategies to combat antimicrobial resistance.
Publication Date: 2019-03-22 PubMed ID: 30683740PubMed Central: PMC6585491DOI: 10.1128/AEM.02665-18Google 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.
  • 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.

This study explores the impact of resistance to macrolide and rifampin, two antibiotics, on the fitness of the bacterium Rhodococcus equi, which is often a cause of severe pneumonia in young horses. The research indicates that the acquired resistance can lessen the robustness of the bacteria in certain conditions and may also be lost over time.

Research Methodology

  • The researchers created three sets of Rhodococcus equi strains. In each set, there were four variants of the bacteria: the regular bacteria, bacteria resistant to macrolide, bacteria resistant to rifampin, and one resistant to both macrolide and rifampin.
  • Growth rate of each strain was measured in various mediums including enriched medium, minimal medium (MM), and minimal medium without iron (MM-I).
  • The survival rate of these strains was also tracked over the course of a year in soil at different temperatures.
  • The team further monitored if these strains maintained their antibiotic resistance through multiple growth cycles, via sequential subculturing.

Key Findings

  • Resistance to macrolide, brought about by the insertion of a mobile element into the bacteria, had minimal effect on the growth of Rhodococcus equi.
  • However, the mutations that caused rifampin resistance in two out of three sets slowed down the bacteria’s growth in MM.
  • The researchers also observed that in soil, Rhodococcus equi strains resistant to macrolide or rifampin had limited growth at all temperatures, except at -20°C, when compared to the non-resistant strain.
  • Over time, during the process of sequential subculturing, resistance to macrolide was lost. Also, in two out of three sets, the rifampin-resistant mutations reverted to the original, non-resistant form.

Implications of the Study

  • This research enhances our understanding of Rhodococcus equi’s behavior. This microbe is not only a significant cause of pneumonia in foals but is also dangerous to humans with compromised immunity.
  • The findings of the study could aid in the development of new strategies to battle antibiotic resistance in bacteria, which is alarming for both horse-rearing industry and human health.

Cite This Article

APA
Willingham-Lane JM, Berghaus LJ, Berghaus RD, Hart KA, Giguère S. (2019). Effect of Macrolide and Rifampin Resistance on the Fitness of Rhodococcus equi. Appl Environ Microbiol, 85(7), e02665-18. https://doi.org/10.1128/AEM.02665-18

Publication

ISSN: 1098-5336
NlmUniqueID: 7605801
Country: United States
Language: English
Volume: 85
Issue: 7
PII: e02665-18

Researcher Affiliations

Willingham-Lane, Jennifer M
  • Department of Large Animal Medicine, University of Georgia, Athens, Georgia, USA jmwlane1@gmail.com.
Berghaus, Londa J
  • Department of Large Animal Medicine, University of Georgia, Athens, Georgia, USA.
Berghaus, Roy D
  • Department of Population Health, University of Georgia, Athens, Georgia, USA.
Hart, Kelsey A
  • Department of Large Animal Medicine, University of Georgia, Athens, Georgia, USA.
Giguère, Steeve
  • Department of Large Animal Medicine, University of Georgia, Athens, Georgia, USA.

MeSH Terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics
  • DNA-Directed RNA Polymerases / genetics
  • Drug Resistance, Bacterial / drug effects
  • Drug Resistance, Bacterial / genetics
  • Horse Diseases / microbiology
  • Horses
  • Humans
  • Macrolides / pharmacology
  • Microbial Sensitivity Tests
  • Rhodococcus equi / drug effects
  • Rhodococcus equi / genetics
  • Rhodococcus equi / growth & development
  • Rifampin / pharmacology

References

This article includes 38 references
  1. Reuss SM, Cohen ND. Update on bacterial pneumonia in the foal and weanling.. Vet Clin North Am Equine Pract 2015 Apr;31(1):121-35.
    doi: 10.1016/j.cveq.2014.11.004pubmed: 25600452google scholar: lookup
  2. Cohen ND. Rhodococcus equi foal pneumonia.. Vet Clin North Am Equine Pract 2014 Dec;30(3):609-22.
    doi: 10.1016/j.cveq.2014.08.010pubmed: 25282322google scholar: lookup
  3. Chaffin MK, Cohen ND, Martens RJ, O'Conor M, Bernstein LR. Evaluation of the efficacy of gallium maltolate for chemoprophylaxis against pneumonia caused by Rhodococcus equi infection in foals.. Am J Vet Res 2011 Jul;72(7):945-57.
    doi: 10.2460/ajvr.72.7.945pubmed: 21728856google scholar: lookup
  4. Ainsworth DM, Eicker SW, Yeagar AE, Sweeney CR, Viel L, Tesarowski D, Lavoie JP, Hoffman A, Paradis MR, Reed SM, Erb HN, Davidow E, Nalevanko M. Associations between physical examination, laboratory, and radiographic findings and outcome and subsequent racing performance of foals with Rhodococcus equi infection: 115 cases (1984-1992).. J Am Vet Med Assoc 1998 Aug 15;213(4):510-5.
    pubmed: 9713534
  5. Collignon PJ, Conly JM, Andremont A, McEwen SA, Aidara-Kane A, Agerso Y, Andremont A, Collignon P, Conly J, Dang Ninh T, Donado-Godoy P, Fedorka-Cray P, Fernandez H, Galas M, Irwin R, Karp B, Matar G, McDermott P, McEwen S, Mitema E, Reid-Smith R, Scott HM, Singh R, DeWaal CS, Stelling J, Toleman M, Watanabe H, Woo GJ. World Health Organization Ranking of Antimicrobials According to Their Importance in Human Medicine: A Critical Step for Developing Risk Management Strategies to Control Antimicrobial Resistance From Food Animal Production.. Clin Infect Dis 2016 Oct 15;63(8):1087-1093.
    doi: 10.1093/cid/ciw475pubmed: 27439526google scholar: lookup
  6. McCracken JL, Slovis NM. Use of thoracic ultrasound for the prevention of Rhodococcus equi pneumonia on endemic farms. Abstr Proc Am Assoc Equine Pract 55:36–44.
  7. Slovis NM, McCracken JL, Mundy G. How to use thoracic ultrasound to screen foals for Rhodococcus equi at affected farms. Abstr Proc Am Assoc Equine Pract 51:274–278.
  8. Venner M, Rödiger A, Laemmer M, Giguère S. Failure of antimicrobial therapy to accelerate spontaneous healing of subclinical pulmonary abscesses on a farm with endemic infections caused by Rhodococcus equi.. Vet J 2012 Jun;192(3):293-8.
    doi: 10.1016/j.tvjl.2011.07.004pubmed: 21924651google scholar: lookup
  9. Giguère S, Lee E, Williams E, Cohen ND, Chaffin MK, Halbert N, Martens RJ, Franklin RP, Clark CC, Slovis NM. Determination of the prevalence of antimicrobial resistance to macrolide antimicrobials or rifampin in Rhodococcus equi isolates and treatment outcome in foals infected with antimicrobial-resistant isolates of R equi.. J Am Vet Med Assoc 2010 Jul 1;237(1):74-81.
    doi: 10.2460/javma.237.1.74pubmed: 20590498google scholar: lookup
  10. Burton AJ, Giguère S, Sturgill TL, Berghaus LJ, Slovis NM, Whitman JL, Levering C, Kuskie KR, Cohen ND. Macrolide- and rifampin-resistant Rhodococcus equi on a horse breeding farm, Kentucky, USA.. Emerg Infect Dis 2013 Feb;19(2):282-5.
    doi: 10.3201/eid1902.121210pmc: PMC3559061pubmed: 23347878google scholar: lookup
  11. Riesenberg A, Feßler AT, Erol E, Prenger-Berninghoff E, Stamm I, Böse R, Heusinger A, Klarmann D, Werckenthin C, Schwarz S. MICs of 32 antimicrobial agents for Rhodococcus equi isolates of animal origin.. J Antimicrob Chemother 2014 Apr;69(4):1045-9.
    doi: 10.1093/jac/dkt460pubmed: 24275117google scholar: lookup
  12. Anastasi E, Giguère S, Berghaus LJ, Hondalus MK, Willingham-Lane JM, MacArthur I, Cohen ND, Roberts MC, Vazquez-Boland JA. Novel transferable erm(46) determinant responsible for emerging macrolide resistance in Rhodococcus equi.. J Antimicrob Chemother 2015 Dec;70(12):3184-90.
    doi: 10.1093/jac/dkv279pubmed: 26377866google scholar: lookup
  13. Andersson DI, Hughes D. Antibiotic resistance and its cost: is it possible to reverse resistance?. Nat Rev Microbiol 2010 Apr;8(4):260-71.
    doi: 10.1038/nrmicro2319pubmed: 20208551google scholar: lookup
  14. Jin DJ, Cashel M, Friedman DI, Nakamura Y, Walter WA, Gross CA. Effects of rifampicin resistant rpoB mutations on antitermination and interaction with nusA in Escherichia coli.. J Mol Biol 1988 Nov 20;204(2):247-61.
    pubmed: 2464690doi: 10.1016/0022-2836(88)90573-6google scholar: lookup
  15. Jin DJ, Gross CA. Mapping and sequencing of mutations in the Escherichia coli rpoB gene that lead to rifampicin resistance.. J Mol Biol 1988 Jul 5;202(1):45-58.
    pubmed: 3050121doi: 10.1016/0022-2836(88)90517-7google scholar: lookup
  16. Mariam DH, Mengistu Y, Hoffner SE, Andersson DI. Effect of rpoB mutations conferring rifampin resistance on fitness of Mycobacterium tuberculosis.. Antimicrob Agents Chemother 2004 Apr;48(4):1289-94.
  17. Yu J, Wu J, Francis KP, Purchio TF, Kadurugamuwa JL. Monitoring in vivo fitness of rifampicin-resistant Staphylococcus aureus mutants in a mouse biofilm infection model.. J Antimicrob Chemother 2005 Apr;55(4):528-34.
    doi: 10.1093/jac/dki053pubmed: 15743898google scholar: lookup
  18. Luangtongkum T, Shen Z, Seng VW, Sahin O, Jeon B, Liu P, Zhang Q. Impaired fitness and transmission of macrolide-resistant Campylobacter jejuni in its natural host.. Antimicrob Agents Chemother 2012 Mar;56(3):1300-8.
    doi: 10.1128/AAC.05516-11pmc: PMC3294946pubmed: 22183170google scholar: lookup
  19. Zou LK, Wang HN, Zeng B, Li JN, Li XT, Zhang AY, Zhou YS, Yang X, Xu CW, Xia QQ. Erythromycin resistance and virulence genes in Enterococcus faecalis from swine in China.. New Microbiol 2011 Jan;34(1):73-80.
    pubmed: 21344149
  20. Hondalus MK, Mosser DM. Survival and replication of Rhodococcus equi in macrophages.. Infect Immun 1994 Oct;62(10):4167-75.
  21. Miranda-CasoLuengo R, Prescott JF, Vázquez-Boland JA, Meijer WG. The intracellular pathogen Rhodococcus equi produces a catecholate siderophore required for saprophytic growth.. J Bacteriol 2008 Mar;190(5):1631-7.
    doi: 10.1128/JB.01570-07pmc: PMC2258663pubmed: 18156254google scholar: lookup
  22. Miranda-Casoluengo R, Coulson GB, Miranda-Casoluengo A, Vázquez-Boland JA, Hondalus MK, Meijer WG. The hydroxamate siderophore rhequichelin is required for virulence of the pathogenic actinomycete Rhodococcus equi.. Infect Immun 2012 Dec;80(12):4106-14.
    doi: 10.1128/IAI.00678-12pmc: PMC3497440pubmed: 22966042google scholar: lookup
  23. Tkachuk-Saad O, Prescott J. Rhodococcus equi plasmids: isolation and partial characterization.. J Clin Microbiol 1991 Dec;29(12):2696-700.
  24. 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.
  25. Hondalus MK. Pathogenesis and virulence of Rhodococcus equi.. Vet Microbiol 1997 Jun 16;56(3-4):257-68.
    pubmed: 9226840doi: 10.1016/s0378-1135(97)00094-1google scholar: lookup
  26. 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.
  27. 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
  28. 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.
  29. von Bargen K, Scraba M, Krämer I, Ketterer M, Nehls C, Krokowski S, Repnik U, Wittlich M, Maaser A, Zapka P, Bunge M, Schlesinger M, Huth G, Klees A, Hansen P, Jeschke A, Bendas G, Utermöhlen O, Griffiths G, Gutsmann T, Wohlmann J, Haas A. Virulence-associated protein A from Rhodococcus equi is an intercompartmental pH-neutralising virulence factor.. Cell Microbiol 2019 Jan;21(1):e12958.
    doi: 10.1111/cmi.12958pubmed: 30251327google scholar: lookup
  30. 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.
  31. Takai S, Fukunaga N, Kamisawa K, Imai Y, Sasaki Y, Tsubaki S. Expression of virulence-associated antigens of Rhodococcus equi is regulated by temperature and pH.. Microbiol Immunol 1996;40(8):591-4.
  32. 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
  33. Billington OJ, McHugh TD, Gillespie SH. Physiological cost of rifampin resistance induced in vitro in Mycobacterium tuberculosis.. Antimicrob Agents Chemother 1999 Aug;43(8):1866-9.
    pmc: PMC89382pubmed: 10428904doi: 10.1128/aac.43.8.1866google scholar: lookup
  34. Landick R, Stewart J, Lee DN. Amino acid changes in conserved regions of the beta-subunit of Escherichia coli RNA polymerase alter transcription pausing and termination.. Genes Dev 1990 Sep;4(9):1623-36.
    pubmed: 2253882doi: 10.1101/gad.4.9.1623google scholar: lookup
  35. Woolcock JB, Farmer AM, Mutimer MD. Selective medium for Corynebacterium equi isolation.. J Clin Microbiol 1979 May;9(5):640-2.
    pmc: PMC275365pubmed: 479362doi: 10.1128/jcm.9.5.640-642.1979google scholar: lookup
  36. Riesenberg A, Feßler AT, Frömke C, Kadlec K, Klarmann D, Kreienbrock L, Werckenthin C, Schwarz S. Harmonization of antimicrobial susceptibility testing by broth microdilution for Rhodococcus equi of animal origin.. J Antimicrob Chemother 2013 Sep;68(9):2173-5.
    doi: 10.1093/jac/dkt134pubmed: 23603553google scholar: lookup
  37. 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
  38. Anastasi E, Giguère S, Berghaus LJ, Hondalus MK, Willingham-Lane JM, MacArthur I, Cohen ND, Roberts MC, Vazquez-Boland JA. Novel transferable erm(46) determinant responsible for emerging macrolide resistance in Rhodococcus equi.. J Antimicrob Chemother 2015 Dec;70(12):3184-90.
    doi: 10.1093/jac/dkv279pubmed: 26377866google scholar: lookup

Citations

This article has been cited 4 times.
  1. Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortázar C, Herskin M, Michel V, Miranda Chueca MÁ, Padalino B, Pasquali P, Roberts HC, Spoolder H, Ståhl K, Velarde A, Viltrop A, Winckler C, Baldinelli F, Broglia A, Kohnle L, Alvarez J. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): antimicrobial-resistant Rhodococcus equi in horses.. EFSA J 2022 Feb;20(2):e07081.
    doi: 10.2903/j.efsa.2022.7081pubmed: 35136423google scholar: lookup
  2. Álvarez-Narváez S, Huber L, Giguère S, Hart KA, Berghaus RD, Sanchez S, Cohen ND. Epidemiology and Molecular Basis of Multidrug Resistance in Rhodococcus equi.. Microbiol Mol Biol Rev 2021 May 19;85(2).
    doi: 10.1128/MMBR.00011-21pubmed: 33853933google scholar: lookup
  3. Álvarez-Narváez S, Giguère S, Berghaus LJ, Dailey C, Vázquez-Boland JA. Horizontal Spread of Rhodococcus equi Macrolide Resistance Plasmid pRErm46 across Environmental Actinobacteria.. Appl Environ Microbiol 2020 Apr 17;86(9).
    doi: 10.1128/AEM.00108-20pubmed: 32169935google scholar: lookup
  4. Willingham-Lane JM, Berghaus LJ, Berghaus RD, Hart KA, Giguère S. Effect of Macrolide and Rifampin Resistance on Fitness of Rhodococcus equi during Intramacrophage Replication and In Vivo.. Infect Immun 2019 Oct;87(10).
    doi: 10.1128/IAI.00281-19pubmed: 31331959google scholar: lookup