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Saylor TC, Casselli T, Lethbridge KG, Moore JP, Owens KM, Brissette CA, Zückert WR, Stevenson B. Borrelia burgdorferi, the Lyme disease spirochete, possesses genetically-encoded responses to doxycycline, but not to amoxicillin. PLoS One 2022; 17:e0274125. [PMID: 36178885 PMCID: PMC9524633 DOI: 10.1371/journal.pone.0274125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/22/2022] [Indexed: 11/18/2022] Open
Abstract
Some species of bacteria respond to antibiotic stresses by altering their transcription profiles, in order to produce proteins that provide protection against the antibiotic. Understanding these compensatory mechanisms allows for informed treatment strategies, and could lead to the development of improved therapeutics. To this end, studies were performed to determine whether Borrelia burgdorferi, the spirochetal agent of Lyme disease, also exhibits genetically-encoded responses to the commonly prescribed antibiotics doxycycline and amoxicillin. After culturing for 24 h in a sublethal concentration of doxycycline, there were significant increases in a substantial number of transcripts for proteins that are involved with translation. In contrast, incubation with a sublethal concentration of amoxicillin did not lead to significant changes in levels of any bacterial transcript. We conclude that B. burgdorferi has a mechanism(s) that detects translational inhibition by doxycycline, and increases production of mRNAs for proteins involved with translation machinery in an attempt to compensate for that stress.
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Affiliation(s)
- Timothy C. Saylor
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, School of Medicine, Lexington, Kentucky, United States of America
| | - Timothy Casselli
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota, United States of America
| | - Kathryn G. Lethbridge
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, School of Medicine, Lexington, Kentucky, United States of America
| | - Jessamyn P. Moore
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, School of Medicine, Lexington, Kentucky, United States of America
| | - Katie M. Owens
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, School of Medicine, Lexington, Kentucky, United States of America
| | - Catherine A. Brissette
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota, United States of America
| | - Wolfram R. Zückert
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kentucky, United States of America
| | - Brian Stevenson
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, School of Medicine, Lexington, Kentucky, United States of America
- Department of Entomology, University of Kentucky, Lexington, Kentucky, United States of America
- * E-mail:
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Lantos PM, Auwaerter PG, Wormser GP. A systematic review of Borrelia burgdorferi morphologic variants does not support a role in chronic Lyme disease. Clin Infect Dis 2013; 58:663-71. [PMID: 24336823 DOI: 10.1093/cid/cit810] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Much of the controversy that surrounds Lyme disease pertains to whether it produces prolonged, treatment-refractory infection, usually referred to as chronic Lyme disease. Some have proposed that round morphologic variants of Borrelia burgdorferi, known variably as "cyst forms" and "L-forms," are responsible for the pathogenesis of chronic Lyme disease. We have undertaken a systematic review of the literature to determine if there is a documented role of these variants in Lyme disease pathogenesis or in syndromes compatible with chronic Lyme disease. METHODS Two systematic literature searches were performed to identify studies in which round morphologic variants of B. burgdorferi have been described in situ in human specimens. RESULTS Our primary literature search identified 6 studies that reported round morphologic variants of B. burgdorferi in specimens obtained from 32 total patients. No study described these forms in patients who had purely subjective symptom complexes (eg, fatigue or pain). No study investigated a causal relationship between morphologic variants and clinical disease or evaluated treatment of morphologic variants in vivo. Of 29 additional studies that described the morphology of B. burgdorferi from patients with Lyme disease, the organism was invariably described as having spirochetal morphology. CONCLUSIONS In the context of the broader medical literature, it is not currently possible to ascribe a pathogenic role to morphologic variants of B. burgdorferi in either typical manifestations of Lyme disease or in other chronic disease states that are often labeled chronic Lyme disease. There is no clinical literature to justify specific treatment of B. burgdorferi morphologic variants.
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Affiliation(s)
- Paul M Lantos
- Departments of Internal Medicine and Pediatrics, Duke University School of Medicine, Durham, North Carolina
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Abstract
The spirochetes in the Borrelia burgdorferi sensu lato genospecies group cycle in nature between tick vectors and vertebrate hosts. The current assemblage of B. burgdorferi sensu lato, of which three species cause Lyme disease in humans, originated from a rapid species radiation that occurred near the origin of the clade. All of these species share a unique genome structure that is highly segmented and predominantly composed of linear replicons. One of the circular plasmids is a prophage that exists as several isoforms in each cell and can be transduced to other cells, likely contributing to an otherwise relatively anemic level of horizontal gene transfer, which nevertheless appears to be adequate to permit strong natural selection and adaptation in populations of B. burgdorferi. Although the molecular genetic toolbox is meager, several antibiotic-resistant mutants have been isolated, and the resistance alleles, as well as some exogenous genes, have been fashioned into markers to dissect gene function. Genetic studies have probed the role of the outer membrane lipoprotein OspC, which is maintained in nature by multiple niche polymorphisms and negative frequency-dependent selection. One of the most intriguing genetic systems in B. burgdorferi is vls recombination, which generates antigenic variation during infection of mammalian hosts.
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MESH Headings
- Alleles
- Animals
- Antigenic Variation
- Antigens, Bacterial/genetics
- Antigens, Bacterial/immunology
- Antigens, Bacterial/metabolism
- Bacterial Outer Membrane Proteins/genetics
- Bacterial Outer Membrane Proteins/metabolism
- Bacterial Proteins/genetics
- Bacterial Proteins/immunology
- Bacterial Proteins/metabolism
- Bacteriophages/genetics
- Bacteriophages/metabolism
- Bacteriophages/pathogenicity
- Borrelia burgdorferi/genetics
- Borrelia burgdorferi/immunology
- Borrelia burgdorferi/pathogenicity
- Borrelia burgdorferi/virology
- DNA, Bacterial/genetics
- DNA, Bacterial/metabolism
- Electroporation
- Evolution, Molecular
- Genes, Bacterial
- Genetic Variation
- Humans
- Ixodes/microbiology
- Linkage Disequilibrium
- Lipoproteins/genetics
- Lipoproteins/immunology
- Lipoproteins/metabolism
- Lyme Disease/microbiology
- Plasmids/genetics
- Plasmids/metabolism
- Prophages/genetics
- Prophages/metabolism
- Recombination, Genetic
- Selection, Genetic
- Species Specificity
- Transduction, Genetic
- Transformation, Genetic
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Affiliation(s)
- Dustin Brisson
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Dan Drecktrah
- Division of Biological Sciences, The University of Montana, Missoula, Montana 59812
| | - Christian H. Eggers
- Department of Biomedical Sciences, Quinnipiac University, Hamden, Connecticut 06518
| | - D. Scott Samuels
- Division of Biological Sciences, The University of Montana, Missoula, Montana 59812
- Center for Biomolecular Structure and Dynamics, The University of Montana, Missoula, Montana 59812
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Brorson O, Brorson SH. An in vitro study of the susceptibility of mobile and cystic forms of Borrelia burgdorferi to metronidazole. APMIS 1999; 107:566-76. [PMID: 10379684 DOI: 10.1111/j.1699-0463.1999.tb01594.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aim of this study was to examine the susceptibility of mobile and cystic forms of Borrelia burgdorferi to metronidazole. Because B. burgdorferi is a microaerobic bacterium like Helicobacter pylori, metronidazole (MZ) was chosen in the susceptibility test. For both microaerobic and aerobic incubation the normal mobile spirochetes were resistant to this antibiotic with an MBC > or = 512 microg/ml. Conversion of mobile spirochetes to cystic forms was not observed when they were incubated with MZ. When they were incubated under microaerobic conditions, the biologically active cystic forms had an MBC > or = 4 microg/ml, but the MBC was > or = 32 microg/ml with aerobic incubation at 37 degrees C. Staining with acridine orange (AO), dark field microscopy (DFM), and transmission electron microscopy (TEM) revealed that the contents of the cysts were degraded when the concentration of MZ was > or = MBC. Some cysts were also ruptured. When incubated with a sufficient concentration of MZ, core structures did not develop inside the cysts, and AO revealed less RNA in the cysts. Our observations may help efforts to treat resistant infections caused by B. burgdorferi with a combination of MZ and other antibiotics in order to eradicate both cystic and mobile forms of B. burgdorferi.
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Affiliation(s)
- O Brorson
- Department of Microbiology, Vestfold Sentralsykehus, Tønsberg, Norway
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Brorson O, Brorson SH. A rapid method for generating cystic forms of Borrelia burgdorferi, and their reversal to mobile spirochetes. APMIS 1998; 106:1131-41. [PMID: 10052721 DOI: 10.1111/j.1699-0463.1998.tb00269.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mobile Borrelia burgdorferi were transferred to distilled water (10(6) per ml). The cultures were observed by dark field microscopy (DFM), interference contrast microscopy (ICM) and transmission electron microscopy (TEM). 95% of the spirochetes were converted to cysts after 1 min, and after 4 h no normal mobile borreliae were observed. When transferred to growth medium (BSK-H), the cysts became smaller and more irregular, and were filled with organic substances. After 1 day, 1-5 thin structures sprouted from the cysts. They continued to grow in both length and thickness until they attained a normal spirochetal structure. Finally, these new-born spirochetes detached from the cysts, by which time their mobility had become normal. The present method for producing large amounts of cystic forms of B. burgdorferi is well suited for further studies of this unique microbe.
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Affiliation(s)
- O Brorson
- Department of Microbiology, Vestfold Sentralsykehus, Tønsberg, Norway
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Brorson O, Brorson SH. In vitro conversion of Borrelia burgdorferi to cystic forms in spinal fluid, and transformation to mobile spirochetes by incubation in BSK-H medium. Infection 1998; 26:144-50. [PMID: 9646104 DOI: 10.1007/bf02771839] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to examine the structural alterations of Borrelia burgdorferi when exposed to spinal fluid. Normal, mobile spirochetes were inoculated into spinal fluid, and the spirochetes were converted to cysts (spheroplast L-forms) after 1-24 h. When these cystic forms were transferred to a rich BSK-H medium, the cysts were converted back to normal, mobile spirochetes after incubation for 9 to 17 days. The cultures were examined by dark field microscopy (DFM), interference contrast microscopy (ICM) and transmission electron microscopy (TEM). When neuroborreliosis is suspected, it is necessary to realize that B. burgdorferi can be present in a cystic form, and these cysts have to be recognized by microscopy. This study may also explain why cultivation of spinal fluid often is negative with respect to B. burgdorferi.
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Affiliation(s)
- O Brorson
- Dept. of Microbiology, Vestfold Sentralsykehus, Tønsberg
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Brorson O, Brorson SH. Transformation of cystic forms of Borrelia burgdorferi to normal, mobile spirochetes. Infection 1997; 25:240-6. [PMID: 9266264 DOI: 10.1007/bf01713153] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of this study was to evaluate the behaviour of Borrelia burgdorferi under controlled conditions. The occurrence of cystic forms of Borrelia burgdorferi in vitro was noted, and these cysts were able to be transformed to normal, mobile spirochetes. B. burgdorferi was cultivated in a commercial culture medium without serum. The spirochetes multiplied only slowly in this medium, and transformation to encysted forms was observed after 1 week. When these cysts were transferred to the same culture medium with rabbit serum, the encysted forms developed into regular, mobile spirochetes after 6 weeks, and their regeneration time was normal. Examination of these cysts in the transmission electron microscope revealed transverse fission inside the cysts. It is probable that similar phenomena may occur in vivo under conditions unfavourable for spirochetes. These observations may help to explain why diagnosis and treatment of B. burgdorferi infections in humans can be difficult.
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Affiliation(s)
- O Brorson
- Dept. of Microbiology, Ullevål University Hospital, Oslo, Norway
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Escudero R, Halluska ML, Backenson PB, Coleman JL, Benach JL. Characterization of the physiological requirements for the bactericidal effects of a monoclonal antibody to OspB of Borrelia burgdorferi by confocal microscopy. Infect Immun 1997; 65:1908-15. [PMID: 9125579 PMCID: PMC175240 DOI: 10.1128/iai.65.5.1908-1915.1997] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A confocal microscopy study was undertaken to characterize the bactericidal effects of the Fab fragments of CB2, an immunoglobulin G1kappa murine monoclonal antibody, to an epitope in the carboxy region of the outer surface protein B (OspB) of Borrelia burgdorferi. Simultaneous direct labeling of both fixed and live spirochetes with fluorochrome-labeled Fab-CB2 and 11G1, and an immunoglobulin Mkappa monoclonal antibody to OspA, showed that OspA and OspB seem to colocalize in dead spirochetes but do not appear to be physically associated when the organisms are alive. A polar bleb composed of a Fab-CB2-OspB complex, followed by incorporation of 11G1-OspA, precedes the formation of a spheroplast. The spheroplasts contain both OspA and OspB and are a terminal stage in the bactericidal process induced by Fab-CB2. Outer membrane destabilization by Fab-CB2, but not cell wall or cytoplasmic membrane alterations, was demonstrated experimentally by the sequential treatment of spirochetes with Fab-CB2 and monoclonal antibodies to flagellin and DnaK. The action of Fab-CB2 is epitope specific, as another monoclonal antibody to an epitope in the amino terminus of OspB was not bactericidal. The bactericidal effect of Fab-CB2 is not dependent on the induction of spirochetal proteases but is dependent on the presence of Ca2+ and Mg2+. Supplementation of Ca2(+)- and Mg2(+)-free medium with these cations restored the bactericidal effects of Fab-CB2. The mechanism by which a Fab fragment of an antibody destroys a bacterium directly may represent a novel form of antibody-organism interaction.
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Affiliation(s)
- R Escudero
- Department of Pathology, State University of New York, Stony Brook 11794, USA
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Millner MM, Thalhammer GH, Dittrich P, Spork KD, Brunner M, Georgopoulos A. beta-lactam antibiotics in the treatment of neuroborreliosis in children: preliminary results. Infection 1996; 24:174-7. [PMID: 8740117 DOI: 10.1007/bf01713334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In vitro beta-lactam antibiotics like ceftriaxone and penicillin G sodium have been shown to be active against Borrelia burgdorferi. Results of quantitative determinations of both antibiotic substances in the CSF for children are limited. Seventy-five children (median age 96 months, range 10 to 176 months) with probable or definite neuroborreliosis were treated with ceftriaxone (1 x 50-90 mg/kg/day) or penicillin G sodium (4 x 80,000-120,000 IU/kg/day) intravenously. On day 10 of therapy levels of penicillin G sodium (1,1.5,2,3,4, 5, or 6 h after i.v. administration), and ceftriaxone (1,2,4,6,12 or 24 h after i.v. administration) in serum and CSF were measured with a micro agar diffusion bioassay. Results demonstrate that after 5 h penicillin G sodium in CSF was above the minimal inhibitory concentration (MIC) but after 6 h penicillin G sodium levels were below the determination limit in 60% of the cases. All ceftriaxone results in CSF-even after 24 h-were above MIC. Penicillin G sodium serum values ranged from 46.6 to 0.1 mg/L (1 to 6 h post dose) and ceftriaxone serum values from 261 to 5 mg/l (1 to 24 h post dose). The role of penicillin G sodium and ceftriaxone and administration intervals of both antibiotics in the therapy of neuroborreliosis in children are discussed.
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Affiliation(s)
- M M Millner
- Universitätskinderklinik Graz, Arbeitsgruppe Kinderneuropsychiatrie, Austria
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