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Borreliella burgdorferi Antimicrobial-Tolerant Persistence in Lyme Disease and Posttreatment Lyme Disease Syndromes. mBio 2022; 13:e0344021. [PMID: 35467428 PMCID: PMC9239140 DOI: 10.1128/mbio.03440-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The annual incidence of Lyme disease, caused by tick-transmitted Borreliella burgdorferi, is estimated to be at least 476,000 cases in the United States and many more worldwide. Ten to 20% of antimicrobial-treated Lyme disease patients display posttreatment Lyme disease syndrome (PTLDS), a clinical complication whose etiology and pathogenesis remain uncertain. Autoimmunity, cross-reactivity, molecular mimicry, coinfections, and borrelial tolerance to antimicrobials/persistence have been hypothesized and studied as potential causes of PTLDS. Studies of borrelial tolerance/persistence in vitro in response to antimicrobials and experimental studies in mice and nonhuman primates, taken together with clinical reports, have revealed that B. burgdorferi becomes tolerant to antimicrobials and may sometimes persist in animals and humans after the currently recommended antimicrobial treatment. Moreover, B. burgdorferi is pleomorphic and can generate viable-but-nonculturable bacteria, states also involved in antimicrobial tolerance. The multiple regulatory pathways and structural genes involved in mediating this tolerance to antimicrobials and environmental stressors by persistence might include the stringent (rel and dksA) and host adaptation (rpoS) responses, sugar metabolism (glpD), and polypeptide transporters (opp). Application of this recently reported knowledge to clinical studies can be expected to clarify the potential role of bacterial antibacterial tolerance/persistence in Lyme disease and PTLDS.
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Sapi E, Kasliwala RS, Ismail H, Torres JP, Oldakowski M, Markland S, Gaur G, Melillo A, Eisendle K, Liegner KB, Libien J, Goldman JE. The Long-Term Persistence of Borrelia burgdorferi Antigens and DNA in the Tissues of a Patient with Lyme Disease. Antibiotics (Basel) 2019; 8:antibiotics8040183. [PMID: 31614557 PMCID: PMC6963883 DOI: 10.3390/antibiotics8040183] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 10/06/2019] [Accepted: 10/09/2019] [Indexed: 01/29/2023] Open
Abstract
Whether Borrelia burgdorferi, the causative agent of Lyme disease, can persist for long periods in the human body has been a controversial question. The objective of this study was to see if we could find B. burgdorferi in a Lyme disease patient after a long clinical course and after long-term antibiotic treatment. Therefore, we investigated the potential presence of B. burgdorferi antigens and DNA in human autopsy tissues from a well-documented serum-, PCR-, and culture-positive Lyme disease patient, a 53-year-old female from northern Westchester County in the lower Hudson Valley Region of New York State, who had received extensive antibiotic treatments during extensive antibiotic treatments over the course of her 16-year-long illness. We also asked what form the organism might take, with special interest in the recently found antibiotic-resistant aggregate form, biofilm. We also examined the host tissues for the presence of inflammatory markers such as CD3+ T lymphocytes. Autopsy tissue sections of the brain, heart, kidney, and liver were analyzed by histological and immunohistochemical methods (IHC), confocal microscopy, fluorescent in situ hybridization (FISH), polymerase chain reaction (PCR), and whole-genome sequencing (WGS)/metagenomics. We found significant pathological changes, including borrelial spirochetal clusters, in all of the organs using IHC combined with confocal microscopy. The aggregates contained a well-established biofilm marker, alginate, on their surfaces, suggesting they are true biofilm. We found B. burgdorferi DNA by FISH, polymerase chain reaction (PCR), and an independent verification by WGS/metagenomics, which resulted in the detection of B. burgdorferi sensu stricto specific DNA sequences. IHC analyses showed significant numbers of infiltrating CD3+ T lymphocytes present next to B. burgdorferi biofilms. In summary, we provide several lines of evidence that suggest that B. burgdorferi can persist in the human body, not only in the spirochetal but also in the antibiotic-resistant biofilm form, even after long-term antibiotic treatment. The presence of infiltrating lymphocytes in the vicinity of B. burgdorferi biofilms suggests that the organism in biofilm form might trigger chronic inflammation.
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Affiliation(s)
- Eva Sapi
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Rumanah S Kasliwala
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Hebo Ismail
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Jason P Torres
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Michael Oldakowski
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Sarah Markland
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Gauri Gaur
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Anthony Melillo
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Klaus Eisendle
- Central Teaching Hospital Bolzano L Böhlerstr, 539100 Bolzano, Italy.
| | - Kenneth B Liegner
- Private practice, 592 Route 22, Suite 1B, Pawling, NY 12564, USA.
- Northwell System, Northern Westchester Hospital, Mount Kisco, NY 10549, USA.
- Health Quest System, Sharon Hospital, Sharon, CT 06069, USA.
| | - Jenny Libien
- Department of Pathology, SUNY Downstate Health Sciences University, Brooklyn, NY 11203, USA.
| | - James E Goldman
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10031, USA.
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Hodzic E, Imai DM, Escobar E. Generality of Post-Antimicrobial Treatment Persistence of Borrelia burgdorferi Strains N40 and B31 in Genetically Susceptible and Resistant Mouse Strains. Infect Immun 2019; 87:e00442-19. [PMID: 31308087 PMCID: PMC6759297 DOI: 10.1128/iai.00442-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 07/11/2019] [Indexed: 01/22/2023] Open
Abstract
A basic feature of infection caused by Borrelia burgdorferi, the etiological agent of Lyme borreliosis, is that persistent infection is the rule in its many hosts. The ability to persist and evade host immune clearance poses a challenge to effective antimicrobial treatment. A link between therapy failure and the presence of persister cells has started to emerge. There is growing experimental evidence that viable but noncultivable spirochetes persist following treatment with several different antimicrobial agents. The current study utilized the mouse model to evaluate if persistence occurs following antimicrobial treatment in disease-susceptible (C3H/HeJ [C3H]) and disease-resistant (C57BL/6 [B6]) mouse strains infected with B. burgdorferi strains N40 and B31 and to confirm the generality of this phenomenon, as well as to assess the persisters' clinical relevance. The status of infection was evaluated at 12 and 18 months after treatment. The results demonstrated that persistent spirochetes remain viable for up to 18 months following treatment, as well as being noncultivable. The phenomenon of persistence in disease-susceptible C3H mice is equally evident in disease-resistant B6 mice and not unique to any particular B. burgdorferi strain. The results also demonstrate that, following antimicrobial treatment, both strains of B. burgdorferi, N40 and B31, lose one or more plasmids. The study demonstrated that noncultivable spirochetes can persist in a host following antimicrobial treatment for a long time but did not demonstrate their clinical relevance in a mouse model of chronic infection. The clinical relevance of persistent spirochetes beyond 18 months following antimicrobial treatment requires further studies in other animal models.
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Affiliation(s)
- Emir Hodzic
- Real-Time PCR Research and Diagnostic Core Facility, School of Veterinary Medicine, University of California at Davis, Davis, California, USA
| | - Denise M Imai
- Comparative Pathology Laboratory, School of Veterinary Medicine, University of California at Davis, Davis, California, USA
| | - Edlin Escobar
- Real-Time PCR Research and Diagnostic Core Facility, School of Veterinary Medicine, University of California at Davis, Davis, California, USA
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Molecular Testing of Serial Blood Specimens from Patients with Early Lyme Disease during Treatment Reveals Changing Coinfection with Mixtures of Borrelia burgdorferi Genotypes. Antimicrob Agents Chemother 2019; 63:AAC.00237-19. [PMID: 31036693 DOI: 10.1128/aac.00237-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 04/24/2019] [Indexed: 01/14/2023] Open
Abstract
Borrelia burgdorferi is the etiological agent of Lyme disease. In the current study, we used direct-detection PCR and electrospray ionization mass spectrometry to monitor and genotype B. burgdorferi isolates from serially collected whole-blood specimens from patients clinically diagnosed with early Lyme disease before and during 21 days of antibiotic therapy. B. burgdorferi isolates were detected up to 3 weeks after the initiation of antibiotic treatment, with ratios of coinfecting B. burgdorferi genotypes changing over time.
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Middelveen MJ, Sapi E, Burke J, Filush KR, Franco A, Fesler MC, Stricker RB. Persistent Borrelia Infection in Patients with Ongoing Symptoms of Lyme Disease. Healthcare (Basel) 2018; 6:E33. [PMID: 29662016 PMCID: PMC6023324 DOI: 10.3390/healthcare6020033] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 03/27/2018] [Accepted: 04/11/2018] [Indexed: 01/06/2023] Open
Abstract
INTRODUCTION Lyme disease is a tickborne illness that generates controversy among medical providers and researchers. One of the key topics of debate is the existence of persistent infection with the Lyme spirochete, Borreliaburgdorferi, in patients who have been treated with recommended doses of antibiotics yet remain symptomatic. Persistent spirochetal infection despite antibiotic therapy has recently been demonstrated in non-human primates. We present evidence of persistent Borrelia infection despite antibiotic therapy in patients with ongoing Lyme disease symptoms. METHODS In this pilot study, culture of body fluids and tissues was performed in a randomly selected group of 12 patients with persistent Lyme disease symptoms who had been treated or who were being treated with antibiotics. Cultures were also performed on a group of ten control subjects without Lyme disease. The cultures were subjected to corroborative microscopic, histopathological and molecular testing for Borrelia organisms in four independent laboratories in a blinded manner. RESULTS Motile spirochetes identified histopathologically as Borrelia were detected in culture specimens, and these spirochetes were genetically identified as Borreliaburgdorferi by three distinct polymerase chain reaction (PCR)-based approaches. Spirochetes identified as Borrelia burgdorferi were cultured from the blood of seven subjects, from the genital secretions of ten subjects, and from a skin lesion of one subject. Cultures from control subjects without Lyme disease were negative for Borrelia using these methods. CONCLUSIONS Using multiple corroborative detection methods, we showed that patients with persistent Lyme disease symptoms may have ongoing spirochetal infection despite antibiotic treatment, similar to findings in non-human primates. The optimal treatment for persistent Borrelia infection remains to be determined.
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Affiliation(s)
| | - Eva Sapi
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Jennie Burke
- Australian Biologics, Sydney, NSW 2000, Australia.
| | - Katherine R Filush
- Department of Biology and Environmental Science, University of New Haven, West Haven, CT 06516, USA.
| | - Agustin Franco
- School of Health Sciences, Universidad Catolica Santiago de Guayaquil, Guayaquil 090615, Ecuador.
| | - Melissa C Fesler
- Union Square Medical Associates, 450 Sutter Street, Suite 1504, San Francisco, CA 94108, USA.
| | - Raphael B Stricker
- Union Square Medical Associates, 450 Sutter Street, Suite 1504, San Francisco, CA 94108, USA.
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Crossland NA, Alvarez X, Embers ME. Late Disseminated Lyme Disease: Associated Pathology and Spirochete Persistence Posttreatment in Rhesus Macaques. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 188:672-682. [PMID: 29242055 PMCID: PMC5840488 DOI: 10.1016/j.ajpath.2017.11.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 11/01/2017] [Accepted: 11/16/2017] [Indexed: 12/11/2022]
Abstract
Nonhuman primates currently serve as the best experimental model for Lyme disease because of their close genetic homology with humans and demonstration of all three phases of disease after infection with Borrelia burgdorferi. We investigated the pathology associated with late disseminated Lyme disease (12 to 13 months after tick inoculation) in doxycycline-treated (28 days; 5 mg/kg, oral, twice daily) and untreated rhesus macaques. Minimal to moderate lymphoplasmacytic inflammation, with a predilection for perivascular spaces and collagenous tissues, was observed in multiple tissues, including the cerebral leptomeninges, brainstem, peripheral nerves from both fore and hind limbs, stifle synovium and perisynovial adipose tissue, urinary bladder, skeletal muscle, myocardium, and visceral pericardium. Indirect immunofluorescence assays that combined monoclonal (outer surface protein A) and polyclonal antibodies were performed on all tissue sections that contained inflammation. Rare morphologically intact spirochetes were observed in the brains of two treated rhesus macaques, the heart of one treated rhesus macaque, and adjacent to a peripheral nerve of an untreated animal. Borrelia antigen staining of probable spirochete cross sections was also observed in heart, skeletal muscle, and near peripheral nerves of treated and untreated animals. These findings support the notion that chronic Lyme disease symptoms can be attributable to residual inflammation in and around tissues that harbor a low burden of persistent host-adapted spirochetes and/or residual antigen.
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Affiliation(s)
- Nicholas A Crossland
- Division of Bacteriology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana; Division of Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana
| | - Xavier Alvarez
- Division of Comparative Pathology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana
| | - Monica E Embers
- Division of Bacteriology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana; Division of Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana.
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Horvatić A, Kuleš J, Guillemin N, Galan A, Mrljak V, Bhide M. High-throughput proteomics and the fight against pathogens. MOLECULAR BIOSYSTEMS 2017; 12:2373-84. [PMID: 27227577 DOI: 10.1039/c6mb00223d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pathogens pose a major threat to human and animal welfare. Understanding the interspecies host-pathogen protein-protein interactions could lead to the development of novel strategies to combat infectious diseases through the rapid development of new therapeutics. The first step in understanding the host-pathogen crosstalk is to identify interacting proteins in order to define crucial hot-spots in the host-pathogen interactome, such as the proposed pharmaceutical targets by means of high-throughput proteomic methodologies. In order to obtain holistic insight into the inter- and intra-species bimolecular interactions, apart from the proteomic approach, sophisticated in silico modeling is used to correlate the obtained large data sets with other omics data and clinical outcomes. Since the main focus in this area has been directed towards human medicine, it is time to extrapolate the existing expertise to a new emerging field: the 'systems veterinary medicine'. Therefore, this review addresses high-throughput mass spectrometry-based technology for monitoring protein-protein interactions in vitro and in vivo and discusses pathogen cultivation, model host cells and available bioinformatic tools employed in vaccine development.
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Affiliation(s)
- Anita Horvatić
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Josipa Kuleš
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Nicolas Guillemin
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Asier Galan
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Vladimir Mrljak
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Mangesh Bhide
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia. and Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy, Kosice, Slovakia and Institute of Neuroimmunology, Slovakia Academy of Sciences, Bratislava, Slovakia
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Van Laar TA, Hole C, Rajasekhar Karna SL, Miller CL, Reddick R, Wormley FL, Seshu J. Statins reduce spirochetal burden and modulate immune responses in the C3H/HeN mouse model of Lyme disease. Microbes Infect 2016; 18:430-435. [PMID: 26993029 DOI: 10.1016/j.micinf.2016.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 03/07/2016] [Indexed: 12/22/2022]
Abstract
Lyme disease (LD) is a systemic disorder caused by Borrelia burgdorferi. Lyme spirochetes encode for a functional 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR EC 1.1.1.88) serving as a rate limiting enzyme of the mevalonate pathway that contribute to components critical for cell wall biogenesis. Statins have been shown to inhibit B. burgdorferi in vitro. Using a mouse model of Lyme disease, we found that statins contribute to reducing bacterial burden and altering the murine immune response to favor clearance of spirochetes.
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Affiliation(s)
- Tricia A Van Laar
- South Texas Center for Emerging Infectious Diseases, Center for Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Camaron Hole
- South Texas Center for Emerging Infectious Diseases, Center for Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - S L Rajasekhar Karna
- South Texas Center for Emerging Infectious Diseases, Center for Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Christine L Miller
- South Texas Center for Emerging Infectious Diseases, Center for Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Robert Reddick
- The Department of Pathology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78249, USA
| | - Floyd L Wormley
- South Texas Center for Emerging Infectious Diseases, Center for Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - J Seshu
- South Texas Center for Emerging Infectious Diseases, Center for Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA.
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Borrelia burgdorferi induces a type I interferon response during early stages of disseminated infection in mice. BMC Microbiol 2016; 16:29. [PMID: 26957120 PMCID: PMC4784397 DOI: 10.1186/s12866-016-0644-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/25/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Lyme borrelia genotypes differ in their capacity to cause disseminated disease. Gene array analysis was employed to profile the host transcriptome induced by Borrelia burgdorferi strains with different capacities for causing disseminated disease in the blood of C3H/HeJ mice during early infection. RESULTS B. burgdorferi B515, a clinical isolate that causes disseminated infection in mice, differentially regulated 236 transcripts (P < 0.05 by ANOVA, with fold change of at least 2). The 216 significantly induced transcripts included interferon (IFN)-responsive genes and genes involved in immunity and inflammation. In contrast, B. burgdorferi B331, a clinical isolate that causes transient skin infection but does not disseminate in C3H/HeJ mice, stimulated changes in only a few genes (1 induced, 4 repressed). Transcriptional regulation of type I IFN and IFN-related genes was measured by quantitative RT-PCR in mouse skin biopsies collected from the site of infection 24 h after inoculation with B. burgdorferi. The mean values for transcripts of Ifnb, Cxcl10, Gbp1, Ifit1, Ifit3, Irf7, Mx1, and Stat2 were found to be significantly increased in B. burgdorferi strain B515-infected mice relative to the control group. In contrast, transcription of these genes was not significantly changed in response to B. burgdorferi strain B331 or B31-4, a mutant that is unable to disseminate. CONCLUSIONS These results establish a positive association between the disseminating capacity of B. burgdorferi and early type I IFN induction in a murine model of Lyme disease.
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Šmit R, Postma MJ. Lyme borreliosis: reviewing potential vaccines, clinical aspects and health economics. Expert Rev Vaccines 2015; 14:1549-61. [DOI: 10.1586/14760584.2015.1091313] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Motor rotation is essential for the formation of the periplasmic flagellar ribbon, cellular morphology, and Borrelia burgdorferi persistence within Ixodes scapularis tick and murine hosts. Infect Immun 2015; 83:1765-77. [PMID: 25690096 DOI: 10.1128/iai.03097-14] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 02/05/2015] [Indexed: 12/13/2022] Open
Abstract
Borrelia burgdorferi must migrate within and between its arthropod and mammalian hosts in order to complete its natural enzootic cycle. During tick feeding, the spirochete transmits from the tick to the host dermis, eventually colonizing and persisting within multiple, distant tissues. This dissemination modality suggests that flagellar motor rotation and, by extension, motility are crucial for infection. We recently reported that a nonmotile flaB mutant that lacks periplasmic flagella is rod shaped and unable to infect mice by needle or tick bite. However, those studies could not differentiate whether motor rotation or merely the possession of the periplasmic flagella was crucial for cellular morphology and host persistence. Here, we constructed and characterized a motB mutant that is nonmotile but retains its periplasmic flagella. Even though ΔmotB bacteria assembled flagella, part of the mutant cell is rod shaped. Cryoelectron tomography revealed that the flagellar ribbons are distorted in the mutant cells, indicating that motor rotation is essential for spirochetal flat-wave morphology. The ΔmotB cells are unable to infect mice, survive in the vector, or migrate out of the tick. Coinfection studies determined that the presence of these nonmotile ΔmotB cells has no effect on the clearance of wild-type spirochetes during murine infection and vice versa. Together, our data demonstrate that while flagellar motor rotation is necessary for spirochetal morphology and motility, the periplasmic flagella display no additional properties related to immune clearance and persistence within relevant hosts.
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