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Zhang JJ, Raghunandanan S, Wang Q, Priya R, Alanazi F, Lou Y, Yang XF. BadR directly represses the expression of the glycerol utilization operon in the Lyme disease pathogen. J Bacteriol 2024; 206:e0034023. [PMID: 38214528 PMCID: PMC10882987 DOI: 10.1128/jb.00340-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/14/2023] [Indexed: 01/13/2024] Open
Abstract
Glycerol utilization as a carbohydrate source by Borreliella burgdorferi, the Lyme disease spirochete, is critical for its successful colonization and persistence in the tick vector. The expression of the glpFKD (glp) operon, which encodes proteins for glycerol uptake/utilization, must be tightly regulated during the enzootic cycle of B. burgdorferi. Previous studies have established that the second messenger cyclic di-GMP (c-di-GMP) is required for the activation of glp expression, while an alternative sigma factor RpoS acts as a negative regulator for glp expression. In the present study, we report identification of a cis element within the 5´ untranslated region of glp that exerts negative regulation of glp expression. Further genetic screen of known and predicted DNA-binding proteins encoded in the genome of B. burgdorferi uncovered that overexpressing Borrelia host adaptation regulator (BadR), a known global regulator, dramatically reduced glp expression. Similarly, the badR mutant significantly increased glp expression. Subsequent electrophoretic mobility shift assay analyses demonstrated that BadR directly binds to this cis element, thereby repressing glp independent of RpoS-mediated repression. The efficiency of BadR binding was further assessed in the presence of c-di-GMP and various carbohydrates. This finding highlights multi-layered positive and negative regulatory mechanisms employed by B. burgdorferi to synchronize glp expression throughout its enzootic cycle.IMPORTANCEBorreliella burgdorferi, the Lyme disease pathogen, must modulate its gene expression differentially to adapt successfully to its two disparate hosts. Previous studies have demonstrated that the glycerol uptake and utilization operon, glpFKD, plays a crucial role in spirochetal survival within ticks. However, the glpFKD expression must be repressed when B. burgdorferi transitions to the mammalian host. In this study, we identified a specific cis element responsible for the repression of glpFKD. We further pinpointed Borrelia host adaptation regulator as the direct binding protein to this cis element, thereby repressing glpFKD expression. This discovery paves the way for a deeper exploration of how zoonotic pathogens sense distinct hosts and switch their carbon source utilization during transmission.
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Affiliation(s)
- Jun-Jie Zhang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Sajith Raghunandanan
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Qian Wang
- Department of Clinical Laboratory, Wenzhou People’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Raj Priya
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Fuad Alanazi
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Yongliang Lou
- Wenzhou Key Laboratory of Sanitary Microbiology, Key Laboratory of Laboratory Medicine, Ministry of Education, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - X. Frank Yang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Jusufovic N, Krusenstjerna AC, Savage CR, Saylor TC, Brissette CA, Zückert WR, Schlax PJ, Motaleb MA, Stevenson B. Borrelia burgdorferi PlzA is a cyclic-di-GMP dependent DNA and RNA binding protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.30.526351. [PMID: 36778503 PMCID: PMC9915621 DOI: 10.1101/2023.01.30.526351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The PilZ domain-containing protein, PlzA, is the only known cyclic di-GMP binding protein encoded by all Lyme disease spirochetes. PlzA has been implicated in the regulation of many borrelial processes, but the effector mechanism of PlzA was not previously known. Here we report that PlzA can bind DNA and RNA and that nucleic acid binding requires c-di-GMP, with the affinity of PlzA for nucleic acids increasing as concentrations of c-di-GMP were increased. A mutant PlzA that is incapable of binding c-di-GMP did not bind to any tested nucleic acids. We also determined that PlzA interacts predominantly with the major groove of DNA and that sequence length plays a role in DNA binding affinity. PlzA is a dual-domain protein with a PilZ-like N-terminal domain linked to a canonical C-terminal PilZ domain. Dissection of the domains demonstrated that the separated N-terminal domain bound nucleic acids independently of c-di-GMP. The C-terminal domain, which includes the c-di-GMP binding motifs, did not bind nucleic acids under any tested conditions. Our data are supported by computational docking, which predicts that c-di-GMP binding at the C-terminal domain stabilizes the overall protein structure and facilitates PlzA-DNA interactions via residues in the N-terminal domain. Based on our data, we propose that levels of c-di-GMP during the various stages of the enzootic life cycle direct PlzA binding to regulatory targets.
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Affiliation(s)
- Nerina Jusufovic
- Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, University of Kentucky, Lexington, Kentucky, 40526-0001, USA
| | - Andrew C. Krusenstjerna
- Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, University of Kentucky, Lexington, Kentucky, 40526-0001, USA
| | - Christina R. Savage
- Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, University of Kentucky, Lexington, Kentucky, 40526-0001, USA
| | - Timothy C. Saylor
- Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, University of Kentucky, Lexington, Kentucky, 40526-0001, USA
| | - Catherine A. Brissette
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58203-9061, USA
| | - Wolfram R. Zückert
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas School of Medicine, Kansas City, KS 66160, USA
| | - Paula J. Schlax
- Department of Chemistry and Biochemistry, Bates College, Lewiston, ME, 04240-6030, USA
| | - Md A. Motaleb
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834-435, USA
| | - Brian Stevenson
- Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, University of Kentucky, Lexington, Kentucky, 40526-0001, USA
- Department of Entomology, University of Kentucky, Lexington, Kentucky, 40526-0001, USA
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Khan F, Jeong GJ, Tabassum N, Kim YM. Functional diversity of c-di-GMP receptors in prokaryotic and eukaryotic systems. Cell Commun Signal 2023; 21:259. [PMID: 37749602 PMCID: PMC10519070 DOI: 10.1186/s12964-023-01263-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 08/09/2023] [Indexed: 09/27/2023] Open
Abstract
Cyclic bis-(3', 5')-dimeric guanosine monophosphate (c-di-GMP) is ubiquitous in many bacterial species, where it functions as a nucleotide-based secondary messenger and is a vital regulator of numerous biological processes. Due to its ubiquity, most bacterial species possess a wide range of downstream receptors that has a binding affinity to c-di-GMP and elicit output responses. In eukaryotes, several enzymes and riboswitches operate as receptors that interact with c-di-GMP and transduce cellular or environmental signals. This review examines the functional variety of receptors in prokaryotic and eukaryotic systems that exhibit distinct biological responses after interacting with c-di-GMP. Evolutionary relationships and similarities in distance among the c-di-GMP receptors in various bacterial species were evaluated to understand their specificities. Furthermore, residues of receptors involved in c-di-GMP binding are summarized. This review facilitates the understanding of how distinct receptors from different origins bind c-di-GMP equally well, yet fulfill diverse biological roles at the interspecies, intraspecies, and interkingdom levels. Furthermore, it also highlights c-di-GMP receptors as potential therapeutic targets, particularly those found in pathogenic microorganisms. Video Abstract.
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Affiliation(s)
- Fazlurrahman Khan
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Geum-Jae Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Nazia Tabassum
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Young-Mog Kim
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
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Van Gundy T, Patel D, Bowler BE, Rothfuss MT, Hall AJ, Davies C, Hall LS, Drecktrah D, Marconi RT, Samuels DS, Lybecker MC. c-di-GMP regulates activity of the PlzA RNA chaperone from the Lyme disease spirochete. Mol Microbiol 2023; 119:711-727. [PMID: 37086029 PMCID: PMC10330241 DOI: 10.1111/mmi.15066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/09/2023] [Accepted: 04/10/2023] [Indexed: 04/23/2023]
Abstract
PlzA is a c-di-GMP-binding protein crucial for adaptation of the Lyme disease spirochete Borrelia (Borreliella) burgdorferi during its enzootic life cycle. Unliganded apo-PlzA is important for vertebrate infection, while liganded holo-PlzA is important for survival in the tick; however, the biological function of PlzA has remained enigmatic. Here, we report that PlzA has RNA chaperone activity that is inhibited by c-di-GMP binding. Holo- and apo-PlzA bind RNA and accelerate RNA annealing, while only apo-PlzA can strand displace and unwind double-stranded RNA. Guided by the crystal structure of PlzA, we identified several key aromatic amino acids protruding from the N- and C-terminal domains that are required for RNA-binding and unwinding activity. Our findings illuminate c-di-GMP as a switch controlling the RNA chaperone activity of PlzA, and we propose that complex RNA-mediated modulatory mechanisms allow PlzA to regulate gene expression during both the vector and host phases of the B. burgdorferi life cycle.
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Affiliation(s)
- Taylor Van Gundy
- Bacterial Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Center for Disease Control and Prevention, Fort Collins, CO 80521, USA
| | - Dhara Patel
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA 23298, USA
| | - Bruce E. Bowler
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, USA
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
| | - Michael T. Rothfuss
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, USA
| | - Allie J. Hall
- Bacterial Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Center for Disease Control and Prevention, Fort Collins, CO 80521, USA
| | - Christopher Davies
- Department of Biochemistry and Molecular Biology, University of Southern Alabama, Mobile, AL 36688, USA
| | - Laura S. Hall
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Dan Drecktrah
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Richard T. Marconi
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA 23298, USA
| | - D. Scott Samuels
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Meghan C. Lybecker
- Bacterial Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Center for Disease Control and Prevention, Fort Collins, CO 80521, USA
- Department of Biology, University of Colorado, 1420 Austin Bluffs Parkway, Colorado Springs CO 80917, USA
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Grassmann AA, Tokarz R, Golino C, McLain MA, Groshong AM, Radolf JD, Caimano MJ. BosR and PlzA reciprocally regulate RpoS function to sustain Borrelia burgdorferi in ticks and mammals. J Clin Invest 2023; 133:e166710. [PMID: 36649080 PMCID: PMC9974103 DOI: 10.1172/jci166710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 01/10/2023] [Indexed: 01/18/2023] Open
Abstract
The RNA polymerase alternative σ factor RpoS in Borrelia burgdorferi (Bb), the Lyme disease pathogen, is responsible for programmatic-positive and -negative gene regulation essential for the spirochete's dual-host enzootic cycle. RpoS is expressed during tick-to-mammal transmission and throughout mammalian infection. Although the mammalian-phase RpoS regulon is well described, its counterpart during the transmission blood meal is unknown. Here, we used Bb-specific transcript enrichment by tick-borne disease capture sequencing (TBDCapSeq) to compare the transcriptomes of WT and ΔrpoS Bb in engorged nymphs and following mammalian host-adaptation within dialysis membrane chambers. TBDCapSeq revealed dramatic changes in the contours of the RpoS regulon within ticks and mammals and further confirmed that RpoS-mediated repression is specific to the mammalian-phase of Bb's enzootic cycle. We also provide evidence that RpoS-dependent gene regulation, including repression of tick-phase genes, is required for persistence in mice. Comparative transcriptomics of engineered Bb strains revealed that the Borrelia oxidative stress response regulator (BosR), a noncanonical Fur family member, and the cyclic diguanosine monophosphate (c-di-GMP) effector PlzA reciprocally regulate the function of RNA polymerase complexed with RpoS. BosR is required for RpoS-mediated transcription activation and repression in addition to its well-defined role promoting transcription of rpoS by the RNA polymerase alternative σ factor RpoN. During transmission, ligand-bound PlzA antagonizes RpoS-mediated repression, presumably acting through BosR.
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Affiliation(s)
| | - Rafal Tokarz
- Center for Infection and Immunity and
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Caroline Golino
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
| | | | - Ashley M. Groshong
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
- Department of Pediatrics
| | - Justin D. Radolf
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
- Department of Pediatrics
- Department of Molecular Biology and Biophysics
- Department of Genetics and Genome Sciences, and
- Department of Immunology, UConn Health, Farmington, Connecticut, USA
| | - Melissa J. Caimano
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
- Department of Pediatrics
- Department of Molecular Biology and Biophysics
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Zhu T, Wang W, Wang H, Zhao Y, Qu D, Wu Y. Mutation of gdpS gene induces a viable but non-culturable state in Staphylococcus epidermidis and changes in the global transcriptional profile. BMC Microbiol 2022; 22:288. [PMID: 36457079 PMCID: PMC9714401 DOI: 10.1186/s12866-022-02708-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 11/21/2022] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND In the genome of staphylococci, only the gdpS gene encodes the conserved GGDEF domain, which is the characteristic of diguanylate cyclases. In our previous study, we have demonstrated that the gdpS gene can modulate biofilm formation by positively regulating the expression of ica operon in Staphylococcus epidermidis. Moreover, this regulation seems to be independent of the c-di-GMP signaling pathway and the protein-coding function of this gene. Therefore, the biological function of the gdpS gene remains to be further investigated. RESULTS In the present study, it was observed that mutation of the gdpS gene induced S. epidermidis to enter into a presumed viable but nonculturable state (VBNC) after cryopreservation with glycerol. Similarly, when moved from liquid to solid culture medium, the gdpS mutant strain also exhibited a VBNC state. Compared with the wild-type strain, the gdpS mutant strain autolyzed more quickly during storage at 4℃, indicating its increased susceptibility to low temperature. Transcriptional profiling analysis showed that the gdpS mutation affected the transcription of 188 genes (92 genes were upregulated and 96 genes were downregulated). Specifically, genes responsible for glycerol metabolism were most markedly upregulated and most of the altered genes in the mutant strain are those involved in nitrogen metabolism. In addition, the most significantly downregulated genes included the betB gene, whose product catalyzes the synthesis of glycine betaine and confers tolerance to cold. CONCLUSION The preliminary results suggest that the gdpS gene may participate in VBNC formation of S. epidermidis in face of adverse environmental factors, which is probably achieved by regulating expression of energy metabolism genes. Besides, the gdpS gene is critical for S. epidermidis to survive low temperature, and the underlying mechanism may be partly explained by its influence on expression of betB gene.
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Affiliation(s)
- Tao Zhu
- grid.443626.10000 0004 1798 4069Department of Medical Microbiology and Immunology, Wannan Medical College, Wuhu, 241002 People’s Republic of China
| | - Wei Wang
- grid.443626.10000 0004 1798 4069Department of Pharmacy, Wannan Medical College, Wuhu, 241002 People’s Republic of China
| | - Han Wang
- grid.443626.10000 0004 1798 4069Department of Pharmacy, Wannan Medical College, Wuhu, 241002 People’s Republic of China
| | - Yanfeng Zhao
- grid.452511.6Department of Laboratory Medicine, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, 210011 People’s Republic of China
| | - Di Qu
- grid.11841.3d0000 0004 0619 8943Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Department of Medical Microbiology and Parasitology, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, 200032 People’s Republic of China
| | - Yang Wu
- grid.11841.3d0000 0004 0619 8943Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Department of Medical Microbiology and Parasitology, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, 200032 People’s Republic of China
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Ramos D, Lasseter AG, Richards CL, Schwarz B, Ghosh S, Victoria B, Bosio CM, Gherardini FC, Jewett MW. Riboflavin salvage by Borrelia burgdorferi supports carbon metabolism and is essential for survival in the tick vector. Mol Microbiol 2022; 118:443-456. [PMID: 36054485 PMCID: PMC9588712 DOI: 10.1111/mmi.14977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 10/20/2023]
Abstract
The Lyme disease agent, Borrelia burgdorferi, harbors a significantly reduced genome and relies on the scavenging of critical nutrients from its tick and mammalian hosts for survival. Riboflavin salvage has been shown to be important for B. burgdorferi infection of mice, yet the contributions of riboflavin to B. burgdorferi metabolism and survival in the tick remain unknown. Using a targeted mass spectrometry approach, we confirmed the importance of bb0318, the putative ATPase component of an ABC-type riboflavin transporter, for riboflavin salvage and the production of FMN and FAD. This analysis further revealed that Δbb0318 B. burgdorferi displayed increased levels of glycerol 3-phosphate compared to the wild-type. The glycerol 3-phosphate dehydrogenase activity of GlpD was found to be FAD-dependent and the transcription and translation of glpD were significantly decreased in Δbb0318 B. burgdorferi. Finally, gene bb0318 was found to be important for maximal spirochete burden in unfed larvae and essential for survival in feeding ticks. Together, these data demonstrate the importance of riboflavin salvage for B. burgdorferi carbon metabolism and survival in ticks.
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Affiliation(s)
- Darlene Ramos
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Amanda G. Lasseter
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Crystal L. Richards
- Laboratory of Bacteriology, Division of Intramural Research, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Benjamin Schwarz
- Laboratory of Bacteriology, Division of Intramural Research, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Susmita Ghosh
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
- Tectonic Therapeutics, Watertown, Massachusetts, USA
| | - Berta Victoria
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Catharine M. Bosio
- Laboratory of Bacteriology, Division of Intramural Research, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Frank C. Gherardini
- Laboratory of Bacteriology, Division of Intramural Research, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Mollie W. Jewett
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
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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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Stevenson B, Krusenstjerna AC, Castro-Padovani TN, Savage CR, Jutras BL, Saylor TC. The Consistent Tick-Vertebrate Infectious Cycle of the Lyme Disease Spirochete Enables Borrelia burgdorferi To Control Protein Expression by Monitoring Its Physiological Status. J Bacteriol 2022; 204:e0060621. [PMID: 35380872 PMCID: PMC9112904 DOI: 10.1128/jb.00606-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The Lyme disease spirochete, Borrelia burgdorferi, persists in nature by alternatingly cycling between ticks and vertebrates. During each stage of the infectious cycle, B. burgdorferi produces surface proteins that are necessary for interactions with the tick or vertebrate tissues it encounters while also repressing the synthesis of unnecessary proteins. Among these are the Erp surface proteins, which are produced during vertebrate infection for interactions with host plasmin, laminin, glycosaminoglycans, and components of the complement system. Erp proteins are not expressed during tick colonization but are induced when the tick begins to ingest blood from a vertebrate host, a time when the bacteria undergo rapid growth and division. Using the erp genes as a model of borrelial gene regulation, our research group has identified three novel DNA-binding proteins that interact with DNA to control erp transcription. At least two of those regulators are, in turn, affected by DnaA, the master regulator of chromosome replication. Our data indicate that B. burgdorferi has evolved to detect the change from slow to rapid replication during tick feeding as a signal to begin expression of Erp and other vertebrate-specific proteins. The majority of other known regulatory factors of B. burgdorferi also respond to metabolic cues. These observations lead to a model in which the Lyme spirochete recognizes unique environmental conditions encountered during the infectious cycle to "know" where they are and adapt accordingly.
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Affiliation(s)
- Brian Stevenson
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
- Department of Entomology, University of Kentucky, Lexington, Kentucky, USA
| | - Andrew C. Krusenstjerna
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Tatiana N. Castro-Padovani
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Christina R. Savage
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Brandon L. Jutras
- Department of Biochemistry, Virginia Tech, Blacksburg, Virginia, USA
| | - Timothy C. Saylor
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
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Drecktrah D, Hall LS, Crouse B, Schwarz B, Richards C, Bohrnsen E, Wulf M, Long B, Bailey J, Gherardini F, Bosio CM, Lybecker MC, Samuels DS. The glycerol-3-phosphate dehydrogenases GpsA and GlpD constitute the oxidoreductive metabolic linchpin for Lyme disease spirochete host infectivity and persistence in the tick. PLoS Pathog 2022; 18:e1010385. [PMID: 35255112 PMCID: PMC8929704 DOI: 10.1371/journal.ppat.1010385] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/17/2022] [Accepted: 02/18/2022] [Indexed: 12/18/2022] Open
Abstract
We have identified GpsA, a predicted glycerol-3-phosphate dehydrogenase, as a virulence factor in the Lyme disease spirochete Borrelia (Borreliella) burgdorferi: GpsA is essential for murine infection and crucial for persistence of the spirochete in the tick. B. burgdorferi has a limited biosynthetic and metabolic capacity; the linchpin connecting central carbohydrate and lipid metabolism is at the interconversion of glycerol-3-phosphate and dihydroxyacetone phosphate, catalyzed by GpsA and another glycerol-3-phosphate dehydrogenase, GlpD. Using a broad metabolomics approach, we found that GpsA serves as a dominant regulator of NADH and glycerol-3-phosphate levels in vitro, metabolic intermediates that reflect the cellular redox potential and serve as a precursor for lipid and lipoprotein biosynthesis, respectively. Additionally, GpsA was required for survival under nutrient stress, regulated overall reductase activity and controlled B. burgdorferi morphology in vitro. Furthermore, during in vitro nutrient stress, both glycerol and N-acetylglucosamine were bactericidal to B. burgdorferi in a GlpD-dependent manner. This study is also the first to identify a suppressor mutation in B. burgdorferi: a glpD deletion restored the wild-type phenotype to the pleiotropic gpsA mutant, including murine infectivity by needle inoculation at high doses, survival under nutrient stress, morphological changes and the metabolic imbalance of NADH and glycerol-3-phosphate. These results illustrate how basic metabolic functions that are dispensable for in vitro growth can be essential for in vivo infectivity of B. burgdorferi and may serve as attractive therapeutic targets. Lyme disease (borreliosis) is the most common tick-borne disease in the Northern hemisphere and its prevalence is increasing. Borrelia burgdorferi, the etiological agent of Lyme disease, is an enzootic pathogen that alternates between a tick vector and vertebrate host. Humans are considered an incidental host after transmission of B. burgdorferi following the bite of an infected tick. The mechanisms by which B. burgdorferi persists in the Ixodid tick, transmits to a vertebrate host and establishes infection are not well understood. Therefore, identifying virulence factors and uncovering the pathogenic strategies in the spirochete remain important to address the public health concerns of Lyme disease. In this study, we identify an enzyme involved in three-carbon metabolism, GpsA, as a new virulence factor with an effect on persistence in ticks. GpsA and GlpD, another enzyme, constitute a bidirectional metabolic node connecting lipid biosynthesis and glycolysis, which serves as the linchpin for regulating carbon utilization for B. burgdorferi throughout its enzootic cycle. Disruption of this node causes a lethal metabolic imbalance revealing a potential therapeutic target for the treatment of Lyme disease.
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Affiliation(s)
- Dan Drecktrah
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
- * E-mail: (DD); (DSS)
| | - Laura S. Hall
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
| | - Bethany Crouse
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
| | - Benjamin Schwarz
- Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Crystal Richards
- Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Eric Bohrnsen
- Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Michael Wulf
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
| | - Bonnie Long
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
| | - Jessica Bailey
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
| | - Frank Gherardini
- Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Catharine M. Bosio
- Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Meghan C. Lybecker
- Department of Biology, University of Colorado, Colorado Springs, Colorado, United States of America
| | - D. Scott Samuels
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, Montana, United States of America
- * E-mail: (DD); (DSS)
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11
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Groshong AM, Grassmann AA, Luthra A, McLain MA, Provatas AA, Radolf JD, Caimano MJ. PlzA is a bifunctional c-di-GMP biosensor that promotes tick and mammalian host-adaptation of Borrelia burgdorferi. PLoS Pathog 2021; 17:e1009725. [PMID: 34265024 PMCID: PMC8323883 DOI: 10.1371/journal.ppat.1009725] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/30/2021] [Accepted: 06/18/2021] [Indexed: 02/05/2023] Open
Abstract
In this study, we examined the relationship between c-di-GMP and its only known effector protein, PlzA, in Borrelia burgdorferi during the arthropod and mammalian phases of the enzootic cycle. Using a B. burgdorferi strain expressing a plzA point mutant (plzA-R145D) unable to bind c-di-GMP, we confirmed that the protective function of PlzA in ticks is c-di-GMP-dependent. Unlike ΔplzA spirochetes, which are severely attenuated in mice, the plzA-R145D strain was fully infectious, firmly establishing that PlzA serves a c-di-GMP-independent function in mammals. Contrary to prior reports, loss of PlzA did not affect expression of RpoS or RpoS-dependent genes, which are essential for transmission, mammalian host-adaptation and murine infection. To ascertain the nature of PlzA's c-di-GMP-independent function(s), we employed infection models using (i) host-adapted mutant spirochetes for needle inoculation of immunocompetent mice and (ii) infection of scid mice with in vitro-grown organisms. Both approaches substantially restored ΔplzA infectivity, suggesting that PlzA enables B. burgdorferi to overcome an early bottleneck to infection. Furthermore, using a Borrelia strain expressing a heterologous, constitutively active diguanylate cyclase, we demonstrate that 'ectopic' production of c-di-GMP in mammals abrogates spirochete virulence and interferes with RpoS function at the post-translational level in a PlzA-dependent manner. Structural modeling and SAXS analysis of liganded- and unliganded-PlzA revealed marked conformational changes that underlie its biphasic functionality. This structural plasticity likely enables PlzA to serve as a c-di-GMP biosensor that in its respective liganded and unliganded states promote vector- and host-adaptation by the Lyme disease spirochete.
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Affiliation(s)
- Ashley M. Groshong
- Department of Medicine, UConn Health, Farmington, Connecticut, United States of America
- Department of Pediatrics, UConn Health, Farmington, Connecticut, United States of America
| | - André A. Grassmann
- Department of Medicine, UConn Health, Farmington, Connecticut, United States of America
| | - Amit Luthra
- Department of Medicine, UConn Health, Farmington, Connecticut, United States of America
| | - Melissa A. McLain
- Department of Medicine, UConn Health, Farmington, Connecticut, United States of America
| | - Anthony A. Provatas
- Center for Environmental Sciences and Engineering, University of Connecticut, Storrs, Connecticut, United States of America
| | - Justin D. Radolf
- Department of Medicine, UConn Health, Farmington, Connecticut, United States of America
- Department of Pediatrics, UConn Health, Farmington, Connecticut, United States of America
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, Connecticut, United States of America
- Department of Genetics and Genome Science, UConn Health, Farmington, Connecticut, United States of America
- Department of Immunology, UConn Health, Farmington, Connecticut, United States of America
| | - Melissa J. Caimano
- Department of Medicine, UConn Health, Farmington, Connecticut, United States of America
- Department of Pediatrics, UConn Health, Farmington, Connecticut, United States of America
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, Connecticut, United States of America
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12
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Singh A, Izac JR, Schuler EJA, Patel DT, Davies C, Marconi RT. High-resolution crystal structure of the Borreliella burgdorferi PlzA protein in complex with c-di-GMP: new insights into the interaction of c-di-GMP with the novel xPilZ domain. Pathog Dis 2021; 79:6297269. [PMID: 34117751 PMCID: PMC8240479 DOI: 10.1093/femspd/ftab030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 06/10/2021] [Indexed: 12/27/2022] Open
Abstract
In the tick-borne pathogens, Borreliella burgdorferi and Borrelia hermsii, c-di-GMP is produced by a single diguanylate cyclase (Rrp1). In these pathogens, the Plz proteins (PlzA, B and C) are the only c-di-GMP receptors identified to date and PlzA is the sole c-di-GMP receptor found in all Borreliella isolates. Bioinformatic analyses suggest that PlzA has a unique PilZN3-PilZ architecture with the relatively uncommon xPilZ domain. Here, we present the crystal structure of PlzA in complex with c-di-GMP (1.6 Å resolution). This is the first structure of a xPilz domain in complex with c-di-GMP to be determined. PlzA has a two-domain structure, where each domain comprises topologically equivalent PilZ domains with minimal sequence identity but remarkable structural similarity. The c-di-GMP binding site is formed by the linker connecting the two domains. While the structure of apo PlzA could not be determined, previous fluorescence resonance energy transfer data suggest that apo and holo forms of the protein are structurally distinct. The information obtained from this study will facilitate ongoing efforts to identify the molecular mechanisms of PlzA-mediated regulation in ticks and mammals.
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Affiliation(s)
- Avinash Singh
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Jerilyn R Izac
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, 1112 East Clay Street, Room 101 McGuire Hall, Richmond, VA 23298-0678, USA
| | - Edward J A Schuler
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, 1112 East Clay Street, Room 101 McGuire Hall, Richmond, VA 23298-0678, USA
| | - Dhara T Patel
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, 1112 East Clay Street, Room 101 McGuire Hall, Richmond, VA 23298-0678, USA
| | - Christopher Davies
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Richard T Marconi
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, 1112 East Clay Street, Room 101 McGuire Hall, Richmond, VA 23298-0678, USA
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13
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Ante VM, Farris LC, Saputra EP, Hall AJ, O'Bier NS, Oliva Chávez AS, Marconi RT, Lybecker MC, Hyde JA. The Borrelia burgdorferi Adenylate Cyclase, CyaB, Is Important for Virulence Factor Production and Mammalian Infection. Front Microbiol 2021; 12:676192. [PMID: 34113333 PMCID: PMC8186283 DOI: 10.3389/fmicb.2021.676192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 04/16/2021] [Indexed: 12/21/2022] Open
Abstract
Borrelia burgdorferi, the causative agent of Lyme disease, traverses through vastly distinct environments between the tick vector and the multiple phases of the mammalian infection that requires genetic adaptation for the progression of pathogenesis. Borrelial gene expression is highly responsive to changes in specific environmental signals that initiate the RpoS regulon for mammalian adaptation, but the mechanism(s) for direct detection of environmental cues has yet to be identified. Secondary messenger cyclic adenosine monophosphate (cAMP) produced by adenylate cyclase is responsive to environmental signals, such as carbon source and pH, in many bacterial pathogens to promote virulence by altering gene regulation. B. burgdorferi encodes a single non-toxin class IV adenylate cyclase (bb0723, cyaB). This study investigates cyaB expression along with its influence on borrelial virulence regulation and mammalian infectivity. Expression of cyaB was specifically induced with co-incubation of mammalian host cells that was not observed with cultivated tick cells suggesting that cyaB expression is influenced by cellular factor(s) unique to mammalian cell lines. The 3′ end of cyaB also encodes a small RNA, SR0623, in the same orientation that overlaps with bb0722. The differential processing of cyaB and SR0623 transcripts may alter the ability to influence function in the form of virulence determinant regulation and infectivity. Two independent cyaB deletion B31 strains were generated in 5A4-NP1 and ML23 backgrounds and complemented with the cyaB ORF alone that truncates SR0623, cyaB with intact SR0623, or cyaB with a mutagenized full-length SR0623 to evaluate the influence on transcriptional and posttranscriptional regulation of borrelial virulence factors and infectivity. In the absence of cyaB, the expression and production of ospC was significantly reduced, while the protein levels for BosR and DbpA were substantially lower than parental strains. Infectivity studies with both independent cyaB mutants demonstrated an attenuated phenotype with reduced colonization of tissues during early disseminated infection. This work suggests that B. burgdorferi utilizes cyaB and potentially cAMP as a regulatory pathway to modulate borrelial gene expression and protein production to promote borrelial virulence and dissemination in the mammalian host.
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Affiliation(s)
- Vanessa M Ante
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Lauren C Farris
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Elizabeth P Saputra
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Allie J Hall
- Department of Biology, University of Colorado at Colorado Springs, Colorado Springs, CO, United States
| | - Nathaniel S O'Bier
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, United States
| | - Adela S Oliva Chávez
- Department of Entomology, Texas A&M University, College Station, TX, United States
| | - Richard T Marconi
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, United States
| | - Meghan C Lybecker
- Department of Biology, University of Colorado at Colorado Springs, Colorado Springs, CO, United States
| | - Jenny A Hyde
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX, United States
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14
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Samuels DS, Lybecker MC, Yang XF, Ouyang Z, Bourret TJ, Boyle WK, Stevenson B, Drecktrah D, Caimano MJ. Gene Regulation and Transcriptomics. Curr Issues Mol Biol 2020; 42:223-266. [PMID: 33300497 DOI: 10.21775/cimb.042.223] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Borrelia (Borreliella) burgdorferi, along with closely related species, is the etiologic agent of Lyme disease. The spirochete subsists in an enzootic cycle that encompasses acquisition from a vertebrate host to a tick vector and transmission from a tick vector to a vertebrate host. To adapt to its environment and persist in each phase of its enzootic cycle, B. burgdorferi wields three systems to regulate the expression of genes: the RpoN-RpoS alternative sigma factor cascade, the Hk1/Rrp1 two-component system and its product c-di-GMP, and the stringent response mediated by RelBbu and DksA. These regulatory systems respond to enzootic phase-specific signals and are controlled or fine- tuned by transcription factors, including BosR and BadR, as well as small RNAs, including DsrABb and Bb6S RNA. In addition, several other DNA-binding and RNA-binding proteins have been identified, although their functions have not all been defined. Global changes in gene expression revealed by high-throughput transcriptomic studies have elucidated various regulons, albeit technical obstacles have mostly limited this experimental approach to cultivated spirochetes. Regardless, we know that the spirochete, which carries a relatively small genome, regulates the expression of a considerable number of genes required for the transitions between the tick vector and the vertebrate host as well as the adaptation to each.
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Affiliation(s)
- D Scott Samuels
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Meghan C Lybecker
- Department of Biology, University of Colorado, Colorado Springs, CO 80918, USA
| | - X Frank Yang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Zhiming Ouyang
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Travis J Bourret
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, 68105 USA
| | - William K Boyle
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, 68105 USA
| | - Brian Stevenson
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky School of Medicine, Lexington, KY 40536, USA
| | - Dan Drecktrah
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Melissa J Caimano
- Departments of Medicine, Pediatrics, and Molecular Biology and Biophysics, UConn Health, Farmington, CT, USA
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15
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Pal U, Kitsou C, Drecktrah D, Yaş ÖB, Fikrig E. Interactions Between Ticks and Lyme Disease Spirochetes. Curr Issues Mol Biol 2020; 42:113-144. [PMID: 33289683 DOI: 10.21775/cimb.042.113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Borrelia burgdorferi sensu lato causes Lyme borreliosis in a variety of animals and humans. These atypical bacterial pathogens are maintained in a complex enzootic life cycle that primarily involves a vertebrate host and Ixodes spp. ticks. In the Northeastern United States, I. scapularis is the main vector, while wild rodents serve as the mammalian reservoir host. As B. burgdorferi is transmitted only by I. scapularis and closely related ticks, the spirochete-tick interactions are thought to be highly specific. Various borrelial and arthropod proteins that directly or indirectly contribute to the natural cycle of B. burgdorferi infection have been identified. Discrete molecular interactions between spirochetes and tick components also have been discovered, which often play critical roles in pathogen persistence and transmission by the arthropod vector. This review will focus on the past discoveries and future challenges that are relevant to our understanding of the molecular interactions between B. burgdorferi and Ixodes ticks. This information will not only impact scientific advancements in the research of tick- transmitted infections but will also contribute to the development of novel preventive measures that interfere with the B. burgdorferi life cycle.
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Affiliation(s)
- Utpal Pal
- Department of Veterinary Medicine, University of Maryland, 8075 Greenmead Drive, College Park, MD 20742, USA
| | - Chrysoula Kitsou
- Department of Veterinary Medicine, University of Maryland, 8075 Greenmead Drive, College Park, MD 20742, USA
| | - Dan Drecktrah
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, USA
| | - Özlem Büyüktanir Yaş
- Department of Microbiology and Clinical Microbiology, Faculty of Medicine, Istinye University, Zeytinburnu, İstanbul, 34010, Turkey
| | - Erol Fikrig
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
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16
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Collins AJ, Smith TJ, Sondermann H, O'Toole GA. From Input to Output: The Lap/c-di-GMP Biofilm Regulatory Circuit. Annu Rev Microbiol 2020; 74:607-631. [PMID: 32689917 DOI: 10.1146/annurev-micro-011520-094214] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Biofilms are the dominant bacterial lifestyle. The regulation of the formation and dispersal of bacterial biofilms has been the subject of study in many organisms. Over the last two decades, the mechanisms of Pseudomonas fluorescens biofilm formation and regulation have emerged as among the best understood of any bacterial biofilm system. Biofilm formation by P. fluorescens occurs through the localization of an adhesin, LapA, to the outer membrane via a variant of the classical type I secretion system. The decision between biofilm formation and dispersal is mediated by LapD, a c-di-GMP receptor, and LapG, a periplasmic protease, which together control whether LapA is retained or released from the cell surface. LapA localization is also controlled by a complex network of c-di-GMP-metabolizing enzymes. This review describes the current understanding of LapA-mediated biofilm formation by P. fluorescens and discusses several emerging models for the regulation and function of this adhesin.
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Affiliation(s)
- Alan J Collins
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, USA;
| | - T Jarrod Smith
- Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, USA; .,Institute of Molecular Biology, University of Oregon, Eugene, Oregon 97403, USA
| | | | - George A O'Toole
- Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, USA;
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