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Akter A, Ananna NF, Ullah H, Islam S, Al Amin M, Kibria KMK, Mahmud S. Computational approach for identifying immunogenic epitopes and optimizing peptide vaccine through in-silico cloning against Mycoplasma genitalium. Heliyon 2024; 10:e28223. [PMID: 38596014 PMCID: PMC11002066 DOI: 10.1016/j.heliyon.2024.e28223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 03/13/2024] [Accepted: 03/13/2024] [Indexed: 04/11/2024] Open
Abstract
Mycoplasma genitalium is a pathogenic microorganism linked to a variety of severe health conditions including ovarian cancer, prostate cancer, HIV transmission, and sexually transmitted diseases. A more effective approach to address the challenges posed by this pathogen, given its high antibiotic resistance rates, could be the development of a peptide vaccine. In this study, we used experimentally validated 13 membrane proteins and their immunogenicity to identify suitable vaccine candidates. Thus, based on immunogenic properties and high conservation among other Mycoplasma genitalium sub-strains, the P110 surface protein is considered for further investigation. Later on, we identified T-cell epitopes and B-cell epitopes from the P110 protein to construct a multiepitope-based vaccine. As a result, the 'NIAPISFSFTPFTAA' T-cell epitope and 'KVKYESSGSNNISFDS' B-cell epitope have shown 99.53% and 87.50% population coverage along with 100% conservancy among the subspecies, and both epitopes were found to be non-allergenic. Furthermore, focusing on molecular docking analysis showed the lowest binding energy for MHC-I (-137.5 kcal/mol) and MHC-II (-183.3 kcal/mol), leading to a satisfactory binding strength between the T-cell epitopes and the MHC molecules. However, the constructed multiepitope vaccine (MEV) consisting of 54 amino acids demonstrates favorable characteristics for a vaccine candidate, including a theoretical pI of 4.25 with a scaled solubility of 0.812 and high antigenicity probabilities. Additionally, structural analyses reveal that the MEV displays substantial alpha helices and extended strands, vital for its immunogenicity. Molecular docking with the human Toll-like receptors TLR1/2 heterodimer shows strong binding affinity, reinforcing its potential to elicit an immune response. Our immune simulation analysis demonstrates immune memory development and robust immunity, while codon adaptation suggests optimal expression in E. coli using the pET-28a(+) vector. These findings collectively highlight the MEV's potential as a valuable vaccine candidate against M. genitalium.
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Affiliation(s)
- Asma Akter
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Natasha Farhin Ananna
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Hedayet Ullah
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Sirajul Islam
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Md Al Amin
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - K M Kaderi Kibria
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Shahin Mahmud
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
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2
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Sprankel L, Scheffer MP, Manger S, Ermel UH, Frangakis AS. Cryo-electron tomography reveals the binding and release states of the major adhesion complex from Mycoplasma genitalium. PLoS Pathog 2023; 19:e1011761. [PMID: 37939157 PMCID: PMC10659161 DOI: 10.1371/journal.ppat.1011761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 11/20/2023] [Accepted: 10/17/2023] [Indexed: 11/10/2023] Open
Abstract
The nap particle is an immunogenic surface adhesion complex from Mycoplasma genitalium. It is essential for motility and responsible for binding sialylated oligosaccharides on the surface of the host cell. The nap particle is composed of two P140-P110 heterodimers, the structure of which was recently solved. However, the interpretation of the mechanism by which the mycoplasma cells orchestrate adhesion remained challenging. Here, we provide cryo-electron tomography structures at ~11 Å resolution, which allow for the distinction between the bound and released state of the nap particle, displaying the in vivo conformational states. Fitting of the atomically resolved structures reveals that bound sialylated oligosaccharides are stabilized by both P110 and P140. Movement of the stalk domains allows for the transfer of conformational changes from the interior of the cell to the binding pocket, thus having the capability of an active release process. It is likely that the same mechanism can be transferred to other Mycoplasma species that belong to the pneumoniae cluster.
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Affiliation(s)
- Lasse Sprankel
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Frankfurt, Germany
| | - Margot P. Scheffer
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Frankfurt, Germany
| | - Sina Manger
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Frankfurt, Germany
| | - Utz H. Ermel
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Frankfurt, Germany
| | - Achilleas S. Frangakis
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Frankfurt, Germany
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3
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Yueyue W, Feichen X, Yixuan X, Lu L, Yiwen C, Xiaoxing Y. Pathogenicity and virulence of Mycoplasma genitalium: Unraveling Ariadne's Thread. Virulence 2022; 13:1161-1183. [PMID: 35791283 PMCID: PMC9262362 DOI: 10.1080/21505594.2022.2095741] [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: 11/24/2022] Open
Abstract
Mycoplasma genitalium, a pathogen from class Mollicutes, has been linked to sexually transmitted diseases and sparked widespread concern. To adapt to its environment, M. genitalium has evolved specific adhesins and motility mechanisms that allow it to adhere to and invade various eukaryotic cells, thereby causing severe damage to the cells. Even though traditional exotoxins have not been identified, secreted nucleases or membrane lipoproteins have been shown to cause cell death and inflammatory injury in M. genitalium infection. However, as both innate and adaptive immune responses are important for controlling infection, the immune responses that develop upon infection do not necessarily eliminate the organism completely. Antigenic variation, detoxifying enzymes, immunoglobulins, neutrophil extracellular trap-degrading enzymes, cell invasion, and biofilm formation are important factors that help the pathogen overcome the host defence and cause chronic infections in susceptible individuals. Furthermore, M. genitalium can increase the susceptibility to several sexually transmitted pathogens, which significantly complicates the persistence and chronicity of M. genitalium infection. This review aimed to discuss the virulence factors of M. genitalium to shed light on its complex pathogenicity and pathogenesis of the infection.
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Affiliation(s)
- Wu Yueyue
- Institute of Pathogenic Biology, Hengyang Medical School; Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - Xiu Feichen
- Institute of Pathogenic Biology, Hengyang Medical School; Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - Xi Yixuan
- Institute of Pathogenic Biology, Hengyang Medical School; Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - Liu Lu
- Institute of Pathogenic Biology, Hengyang Medical School; Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - Chen Yiwen
- Institute of Pathogenic Biology, Hengyang Medical School; Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - You Xiaoxing
- Institute of Pathogenic Biology, Hengyang Medical School; Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
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4
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Extraction, Cloning and Bioinformatics Analysis of Mycoplasma genitalium MG428 Protein. Jundishapur J Microbiol 2022. [DOI: 10.5812/jjm.121644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Mycoplasma genitalium is a sexually transmitted human pathogen, causing numerous reproductive tract diseases in both genders. MG428 is a positive regulator of surface exposure protein gene recombination and an alternative sigma factor of M. genitalium. Objectives: We extracted and cloned the MG428 gene and bioinformatics analyzed its protein structure in this study. Methods: We designed specific primers based on the MG428 gene sequence of M. genitalium. The MG428 gene was amplified using PCR techniques and ligated into the pGEM-T easy vector. The positive clones were verified by DNA sequencing. The MG428 protein biological characteristics and structure was analysed by biological characteristics. Results: The MG428 gene of M. genitalium has a length of 513 bp and encodes 171 amino acids. No coiled-coil conformation, possible transmembrane helices, or signal peptide was found in the MG428 protein. The MG428 protein was located in the nucleoid of bacteria, and its 3D structure was similar to that of the sigma-H factor of Pseudomonas aeruginosa. A total of 14 B cell epitopes in MG428 were predicted. Conclusions: We successfully cloned the MG428 protein of M. genitalium and predicted its structure and function. The results of this study could provide a research direction for medicine screening against M. genitalium.
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Mycoplasma genitalium Protein of Adhesion Promotes the Early Proliferation of Human Urothelial Cells by Interacting with RPL35. Pathogens 2021; 10:pathogens10111449. [PMID: 34832605 PMCID: PMC8621731 DOI: 10.3390/pathogens10111449] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/28/2021] [Accepted: 11/03/2021] [Indexed: 11/29/2022] Open
Abstract
Mycoplasma genitalium is a newly recognized pathogen associated with sexually transmitted diseases (STDs). MgPa, the adhesion protein of Mycoplasma genitalium, is the main adhesin and the key factor for M. genitalium interacting with host cells. Currently, the long-term survival mechanism of M. genitalium in the host is not clear. In this study, a T7 phage-displayed human urothelial cell (SV-HUC-1) cDNA library was constructed, and the interaction of MgPa was screened from this library using the recombinant MgPa (rMgPa) as a target molecule. We verified that 60S ribosomal protein L35 (RPL35) can interact with MgPa using far-Western blot and co-localization analysis. According to the results of tandem mass tag (TMT) labeling and proteome quantitative analysis, there were altogether 407 differentially expressed proteins between the pcDNA3.1(+)/MgPa-transfected cells and non-transfected cells, of which there were 6 downregulated proteins and 401 upregulated proteins. The results of qRT-PCR demonstrated that interaction between rMgPa and RPL35 could promote the expressions of EIF2, SRP68, SERBP1, RPL35A, EGF, and TGF-β. 3-(4,5)-Dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide bromide (MTT) assays corroborated that the interaction between rMgPa and RPL35 could promote SV-HUC-1 cell proliferation. Therefore, our findings indicated that the interaction between rMgPa and RPL35 can enhance the expressions of transcription-initiation and translation-related proteins and thus promote cell proliferation. This study elucidates a new biological function of MgPa and can explain this new mechanism of M. genitalium in the host.
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6
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Mizutani M, Sasajima Y, Miyata M. Force and Stepwise Movements of Gliding Motility in Human Pathogenic Bacterium Mycoplasma pneumoniae. Front Microbiol 2021; 12:747905. [PMID: 34630372 PMCID: PMC8498583 DOI: 10.3389/fmicb.2021.747905] [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: 07/27/2021] [Accepted: 08/24/2021] [Indexed: 11/23/2022] Open
Abstract
Mycoplasma pneumoniae, a human pathogenic bacterium, binds to sialylated oligosaccharides and glides on host cell surfaces via a unique mechanism. Gliding motility is essential for initiating the infectious process. In the present study, we measured the stall force of an M. pneumoniae cell carrying a bead that was manipulated using optical tweezers on two strains. The stall forces of M129 and FH strains were averaged to be 23.7 and 19.7 pN, respectively, much weaker than those of other bacterial surface motilities. The binding activity and gliding speed of the M129 strain on sialylated oligosaccharides were eight and two times higher than those of the FH strain, respectively, showing that binding activity is not linked to gliding force. Gliding speed decreased when cell binding was reduced by addition of free sialylated oligosaccharides, indicating the existence of a drag force during gliding. We detected stepwise movements, likely caused by a single leg under 0.2-0.3 mM free sialylated oligosaccharides. A step size of 14-19 nm showed that 25-35 propulsion steps per second are required to achieve the usual gliding speed. The step size was reduced to less than half with the load applied using optical tweezers, showing that a 2.5 pN force from a cell is exerted on a leg. The work performed in this step was 16-30% of the free energy of the hydrolysis of ATP molecules, suggesting that this step is linked to the elementary process of M. pneumoniae gliding. We discuss a model to explain the gliding mechanism, based on the information currently available.
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Affiliation(s)
- Masaki Mizutani
- Graduate School of Science, Osaka City University, Osaka, Japan
| | - Yuya Sasajima
- Graduate School of Science, Osaka City University, Osaka, Japan
| | - Makoto Miyata
- Graduate School of Science, Osaka City University, Osaka, Japan.,The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Osaka, Japan
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7
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Santos Junior MN, de Macêdo Neres NS, Campos GB, Bastos BL, Timenetsky J, Marques LM. A Review of Ureaplasma diversum: A Representative of the Mollicute Class Associated With Reproductive and Respiratory Disorders in Cattle. Front Vet Sci 2021; 8:572171. [PMID: 33681318 PMCID: PMC7930009 DOI: 10.3389/fvets.2021.572171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 01/13/2021] [Indexed: 12/22/2022] Open
Abstract
The Mollicutes class encompasses wall-less microbes with a reduced genome. They may infect plants, insects, humans, and animals including those on farms and in livestock. Ureaplasma diversum is a mollicute associated with decreased reproduction mainly in the conception rate in cattle, as well as weight loss and decreased quality in milk production. Therefore, U. diversum infection contributes to important economic losses, mainly in large cattle-producing countries such as the United States, China, Brazil, and India. The characteristics of Mollicutes, virulence, and pathogenic variations make it difficult to control their infections. Genomic analysis, prevalence studies, and immunomodulation assays help better understand the pathogenesis of bovine ureaplasma. Here we present the main features of transmission, virulence, immune response, and pathogenesis of U. diversum in bovines.
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Affiliation(s)
- Manoel Neres Santos Junior
- Department of Biointeraction, Multidisciplinary Institute of Health, Universidade Federal da Bahia, Vitória da Conquista, Brazil
- Department of Microbiology, State University of Santa Cruz (UESC), Ilhéus, Brazil
| | - Nayara Silva de Macêdo Neres
- Department of Biointeraction, Multidisciplinary Institute of Health, Universidade Federal da Bahia, Vitória da Conquista, Brazil
| | - Guilherme Barreto Campos
- Department of Biointeraction, Multidisciplinary Institute of Health, Universidade Federal da Bahia, Vitória da Conquista, Brazil
| | - Bruno Lopes Bastos
- Department of Biointeraction, Multidisciplinary Institute of Health, Universidade Federal da Bahia, Vitória da Conquista, Brazil
| | - Jorge Timenetsky
- Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Lucas Miranda Marques
- Department of Biointeraction, Multidisciplinary Institute of Health, Universidade Federal da Bahia, Vitória da Conquista, Brazil
- Department of Microbiology, State University of Santa Cruz (UESC), Ilhéus, Brazil
- Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
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8
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Harne S, Gayathri P, Béven L. Exploring Spiroplasma Biology: Opportunities and Challenges. Front Microbiol 2020; 11:589279. [PMID: 33193251 PMCID: PMC7609405 DOI: 10.3389/fmicb.2020.589279] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/28/2020] [Indexed: 11/13/2022] Open
Abstract
Spiroplasmas are cell-wall-deficient helical bacteria belonging to the class Mollicutes. Their ability to maintain a helical shape in the absence of cell wall and their motility in the absence of external appendages have attracted attention from the scientific community for a long time. In this review we compare and contrast motility, shape determination and cytokinesis mechanisms of Spiroplasma with those of other Mollicutes and cell-walled bacteria. The current models for rod-shape determination and cytokinesis in cell-walled bacteria propose a prominent role for the cell wall synthesis machinery. These models also involve the cooperation of the actin-like protein MreB and FtsZ, the bacterial homolog of tubulin. However the exact role of the cytoskeletal proteins is still under much debate. Spiroplasma possess MreBs, exhibit a rod-shape dependent helical morphology, and divide by an FtsZ-dependent mechanism. Hence, spiroplasmas represent model organisms for deciphering the roles of MreBs and FtsZ in fundamental mechanisms of non-spherical shape determination and cytokinesis in bacteria, in the absence of a cell wall. Identification of components implicated in these processes and deciphering their functions would require genetic experiments. Challenges in genetic manipulations in spiroplasmas are a major bottleneck in understanding their biology. We discuss advancements in genome sequencing, gene editing technologies, super-resolution microscopy and electron cryomicroscopy and tomography, which can be employed for addressing long-standing questions related to Spiroplasma biology.
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Affiliation(s)
- Shrikant Harne
- Indian Institute of Science Education and Research, Pune, India
| | | | - Laure Béven
- INRAE, UMR 1332, Biologie du Fruit et Pathologie, University of Bordeaux, Bordeaux, France
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9
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Vizarraga D, Pérez-Luque R, Martín J, Fita I, Aparicio D. Alternative conformation of the C-domain of the P140 protein from Mycoplasma genitalium. Acta Crystallogr F Struct Biol Commun 2020; 76:508-516. [PMID: 33135669 PMCID: PMC7605107 DOI: 10.1107/s2053230x20012297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/07/2020] [Indexed: 11/10/2022] Open
Abstract
The human pathogen Mycoplasma genitalium is responsible for urethritis in men, and for cervicitis and pelvic inflammatory disease in women. The adherence of M. genitalium to host target epithelial cells is mediated through an adhesion complex called Nap, which is essential for infectivity. Nap is a transmembrane dimer of heterodimers of the immunodominant proteins P110 and P140. The M. genitalium genome contains multiple copies of portions that share homology with the extracellular regions of P140 and P110 encoded by the genes mg191 and mg192, respectively. Homologous recombination between the genes and the copies allows the generation of a large diversity of P140 and P110 variants to overcome surveillance by the host immune system. Interestingly, the C-terminal domain (C-domain) of the extracellular region of P140, which is essential for the function of Nap by acting as a flexible stalk anchoring the protein to the mycoplasma membrane, presents a low degree of sequence variability. In the present work, the X-ray crystal structures of two crystal forms of a construct of the P140 C-domain are reported. In both crystal forms, the construct forms a compact octamer with D4 point-group symmetry. The structure of the C-domain determined in this work presents significant differences with respect to the structure of the C-domain found recently in intact P140. The structural plasticity of the C-domain appears to be a possible mechanism that may help in the functioning of the mycoplasma adhesion complex.
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Affiliation(s)
- David Vizarraga
- Department of Structural Biology, Institut de Biologia Molecular de Barcelona (IBMB–CSIC), Parc Científic de Barcelona, Baldiri Reixac 10-12, 08028 Barcelona, Spain
| | - Rosa Pérez-Luque
- Department of Structural Biology, Institut de Biologia Molecular de Barcelona (IBMB–CSIC), Parc Científic de Barcelona, Baldiri Reixac 10-12, 08028 Barcelona, Spain
| | - Jesús Martín
- Department of Structural Biology, Institut de Biologia Molecular de Barcelona (IBMB–CSIC), Parc Científic de Barcelona, Baldiri Reixac 10-12, 08028 Barcelona, Spain
| | - Ignacio Fita
- Department of Structural Biology, Institut de Biologia Molecular de Barcelona (IBMB–CSIC), Parc Científic de Barcelona, Baldiri Reixac 10-12, 08028 Barcelona, Spain
| | - David Aparicio
- Department of Structural Biology, Institut de Biologia Molecular de Barcelona (IBMB–CSIC), Parc Científic de Barcelona, Baldiri Reixac 10-12, 08028 Barcelona, Spain
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10
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Garcia-Morales L, Ruiz E, Gourgues G, Rideau F, Piñero-Lambea C, Lluch-Senar M, Blanchard A, Lartigue C. A RAGE Based Strategy for the Genome Engineering of the Human Respiratory Pathogen Mycoplasma pneumoniae. ACS Synth Biol 2020; 9:2737-2748. [PMID: 33017534 DOI: 10.1021/acssynbio.0c00263] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Genome engineering of microorganisms has become a standard in microbial biotechnologies. Several efficient tools are available for the genetic manipulation of model bacteria such as Escherichia coli and Bacillus subtilis, or the yeast Saccharomyces cerevisiae. Difficulties arise when transferring these tools to nonmodel organisms. Synthetic biology strategies relying on genome transplantation (GT) aim at using yeast cells for engineering bacterial genomes cloned as artificial chromosomes. However, these strategies remain unsuccessful for many bacteria, including Mycoplasma pneumoniae (MPN), a human pathogen infecting the respiratory tract that has been extensively studied as a model for systems biology of simple unicellular organisms. Here, we have designed a novel strategy for genome engineering based on the recombinase-assisted genomic engineering (RAGE) technology for editing the MPN genome. Using this strategy, we have introduced a 15 kbp fragment at a specific locus of the MPN genome and replaced 38 kbp from its genome by engineered versions modified either in yeast or in E. coli. A strain harboring a synthetic version of this fragment cleared of 13 nonessential genes could also be built and propagated in vitro. These strains were depleted of known virulence factors aiming at creating an avirulent chassis for SynBio applications. Such a chassis and technology are a step forward to build vaccines or deliver therapeutic compounds in the lungs to prevent or cure respiratory diseases in humans.
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Affiliation(s)
- Luis Garcia-Morales
- Univ. Bordeaux, INRAE, Biologie du Fruit et Pathologie, UMR 1332, F-33140 Villenave d’Ornon, France
| | - Estelle Ruiz
- Univ. Bordeaux, INRAE, Biologie du Fruit et Pathologie, UMR 1332, F-33140 Villenave d’Ornon, France
| | - Géraldine Gourgues
- Univ. Bordeaux, INRAE, Biologie du Fruit et Pathologie, UMR 1332, F-33140 Villenave d’Ornon, France
| | - Fabien Rideau
- Univ. Bordeaux, INRAE, Biologie du Fruit et Pathologie, UMR 1332, F-33140 Villenave d’Ornon, France
| | - Carlos Piñero-Lambea
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Maria Lluch-Senar
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Alain Blanchard
- Univ. Bordeaux, INRAE, Biologie du Fruit et Pathologie, UMR 1332, F-33140 Villenave d’Ornon, France
| | - Carole Lartigue
- Univ. Bordeaux, INRAE, Biologie du Fruit et Pathologie, UMR 1332, F-33140 Villenave d’Ornon, France
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11
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Vizarraga D, Kawamoto A, Matsumoto U, Illanes R, Pérez-Luque R, Martín J, Mazzolini R, Bierge P, Pich OQ, Espasa M, Sanfeliu I, Esperalba J, Fernández-Huerta M, Scheffer MP, Pinyol J, Frangakis AS, Lluch-Senar M, Mori S, Shibayama K, Kenri T, Kato T, Namba K, Fita I, Miyata M, Aparicio D. Immunodominant proteins P1 and P40/P90 from human pathogen Mycoplasma pneumoniae. Nat Commun 2020; 11:5188. [PMID: 33057023 PMCID: PMC7560827 DOI: 10.1038/s41467-020-18777-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 09/08/2020] [Indexed: 12/19/2022] Open
Abstract
Mycoplasma pneumoniae is a bacterial human pathogen that causes primary atypical pneumonia. M. pneumoniae motility and infectivity are mediated by the immunodominant proteins P1 and P40/P90, which form a transmembrane adhesion complex. Here we report the structure of P1, determined by X-ray crystallography and cryo-electron microscopy, and the X-ray structure of P40/P90. Contrary to what had been suggested, the binding site for sialic acid was found in P40/P90 and not in P1. Genetic and clinical variability concentrates on the N-terminal domain surfaces of P1 and P40/P90. Polyclonal antibodies generated against the mostly conserved C-terminal domain of P1 inhibited adhesion of M. pneumoniae, and serology assays with sera from infected patients were positive when tested against this C-terminal domain. P40/P90 also showed strong reactivity against human infected sera. The architectural elements determined for P1 and P40/P90 open new possibilities in vaccine development against M. pneumoniae infections.
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Affiliation(s)
- David Vizarraga
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Akihiro Kawamoto
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan.,Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - U Matsumoto
- Graduate School of Science, Osaka City University, Osaka, 558-8585, Japan
| | - Ramiro Illanes
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Rosa Pérez-Luque
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Jesús Martín
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Rocco Mazzolini
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr Aiguader 88, 08003, Barcelona, Spain
| | - Paula Bierge
- Laboratori de Recerca en Microbiologia i Malalties Infeccioses, Institut d'Investigació i Innovació Parc Taulí (I3PT), Hospital Universitari Parc Taulí, Universitat Autònoma de Barcelona, 08208, Sabadell, Spain
| | - Oscar Q Pich
- Laboratori de Recerca en Microbiologia i Malalties Infeccioses, Institut d'Investigació i Innovació Parc Taulí (I3PT), Hospital Universitari Parc Taulí, Universitat Autònoma de Barcelona, 08208, Sabadell, Spain.,Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Mateu Espasa
- Departament de Microbiologia, Hospital Universitari Parc Taulí, Universitat Autònoma de Barcelona, 08208, Sabadell, Spain
| | - Isabel Sanfeliu
- Departament de Microbiologia, Hospital Universitari Parc Taulí, Universitat Autònoma de Barcelona, 08208, Sabadell, Spain
| | - Juliana Esperalba
- Departament de Microbiologia, Hospital Universitari Vall d´Hebron, Universitat Autònoma de Barcelona, 08035, Barcelona, Spain
| | - Miguel Fernández-Huerta
- Departament de Microbiologia, Hospital Universitari Vall d´Hebron, Universitat Autònoma de Barcelona, 08035, Barcelona, Spain
| | - Margot P Scheffer
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Jaume Pinyol
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Achilleas S Frangakis
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Maria Lluch-Senar
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr Aiguader 88, 08003, Barcelona, Spain
| | - Shigetarou Mori
- Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Keigo Shibayama
- Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tsuyoshi Kenri
- Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takayuki Kato
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan.,Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Keiichi Namba
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan.,RIKEN Center for Biosystems Dynamics Research and SPring-8 Center, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan.,JEOL YOKOGUSHI Research Alliance Laboratories, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Ignacio Fita
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Makoto Miyata
- Graduate School of Science, Osaka City University, Osaka, 558-8585, Japan. .,The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Osaka, 558-8585, Japan.
| | - David Aparicio
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain.
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12
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Wood GE, Iverson-Cabral SL, Gillespie CW, Lowens MS, Manhart LE, Totten PA. Sequence variation and immunogenicity of the Mycoplasma genitalium MgpB and MgpC adherence proteins during persistent infection of men with non-gonococcal urethritis. PLoS One 2020; 15:e0240626. [PMID: 33045031 PMCID: PMC7549776 DOI: 10.1371/journal.pone.0240626] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/29/2020] [Indexed: 11/19/2022] Open
Abstract
Mycoplasma genitalium is a sexually transmitted bacterial pathogen that infects men and women. Antigenic variation of MgpB and MgpC, the immunodominant adherence proteins of M. genitalium, is thought to contribute to immune evasion and chronic infection. We investigated the evolution of mgpB and mgpC sequences in men with non-gonococcal urethritis persistently infected with M. genitalium, including two men with anti-M. genitalium antibodies at enrollment and two that developed antibodies during follow-up. Each of the four patients was persistently infected with a different strain type and each patient produced antibodies targeting MgpB and MgpC. Amino acid sequence evolution in the variable regions of MgpB and MgpC occurred in all four patients with changes observed in single and multiple variable regions over time. Using the available crystal structure of MgpC of the G37 type strain we found that predicted conformational B cell epitopes localize predominantly to the variable region of MgpC, amino acids that changed during patient infection lie in these epitopes, and variant amino acids are in close proximity to the conserved sialic acid binding pocket. These findings support the hypothesis that sequence variation functions to avoid specific antibodies thereby contributing to persistence in the genital tract.
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Affiliation(s)
- Gwendolyn E. Wood
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Stefanie L. Iverson-Cabral
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Catherine W. Gillespie
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington, United States of America
| | - M. Sylvan Lowens
- Public Health - Seattle & King County Sexual Health Clinic, Seattle, Washington, United States of America
| | - Lisa E. Manhart
- Department of Epidemiology, University of Washington, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
| | - Patricia A. Totten
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Global Health, Pathobiology Interdisciplinary Program, University of Washington, Seattle, Washington, United States of America
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13
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Aparicio D, Scheffer MP, Marcos-Silva M, Vizarraga D, Sprankel L, Ratera M, Weber MS, Seybert A, Torres-Puig S, Gonzalez-Gonzalez L, Reitz J, Querol E, Piñol J, Pich OQ, Fita I, Frangakis AS. Structure and mechanism of the Nap adhesion complex from the human pathogen Mycoplasma genitalium. Nat Commun 2020; 11:2877. [PMID: 32513917 PMCID: PMC7280502 DOI: 10.1038/s41467-020-16511-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/06/2020] [Indexed: 11/09/2022] Open
Abstract
Mycoplasma genitalium is a human pathogen adhering to host target epithelial cells and causing urethritis, cervicitis and pelvic inflammatory disease. Essential for infectivity is a transmembrane adhesion complex called Nap comprising proteins P110 and P140. Here we report the crystal structure of P140 both alone and in complex with the N-terminal domain of P110. By cryo-electron microscopy (cryo-EM) and tomography (cryo-ET) we find closed and open Nap conformations, determined at 9.8 and 15 Å, respectively. Both crystal structures and the cryo-EM structure are found in a closed conformation, where the sialic acid binding site in P110 is occluded. By contrast, the cryo-ET structure shows an open conformation, where the binding site is accessible. Structural information, in combination with functional studies, suggests a mechanism for attachment and release of M. genitalium to and from the host cell receptor, in which Nap conformations alternate to sustain motility and guarantee infectivity.
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Affiliation(s)
- David Aparicio
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Margot P Scheffer
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Marina Marcos-Silva
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - David Vizarraga
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Lasse Sprankel
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Mercè Ratera
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Miriam S Weber
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Anja Seybert
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Sergi Torres-Puig
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Luis Gonzalez-Gonzalez
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Julian Reitz
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Enrique Querol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Jaume Piñol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Oscar Q Pich
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain.
| | - Ignacio Fita
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain.
| | - Achilleas S Frangakis
- Buchmann Institute for Molecular Life Sciences, Max-von-Laue Str. 15, 60438, Frankfurt, Germany.
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14
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Single-Locus-Sequence-Based Typing of the mgpB Gene Reveals Transmission Dynamics in Mycoplasma genitalium. J Clin Microbiol 2020; 58:JCM.01886-19. [PMID: 31941694 DOI: 10.1128/jcm.01886-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/11/2020] [Indexed: 11/20/2022] Open
Abstract
Sexually transmitted infections (STIs) by Mycoplasma genitalium are a major problem worldwide, especially given their marked and rapid propensity for developing antimicrobial resistance. Since very few treatment options exist, clinicians face an important challenge in the management of the infection. In this scenario, little is known regarding the transmission dynamics of M. genitalium and the epidemiology of antimicrobial resistance. This mgpB-based molecular typing study, conducted among 54 asymptomatically infected individuals prospectively recruited from an STI screening service, reveals two distinct epidemiological clusters that significantly correlate with sexual conduct in heterosexuals and men who have sex with men (MSM), respectively. This well-defined structuration suggests the presence of two independent sexual networks with little connectivity between them. On the other hand, the study demonstrates the multiclonal feature of the emergence of antibiotic resistance in M. genitalium to both macrolides and fluoroquinolones. The high prevalence of macrolide resistance in M. genitalium among MSM, influenced by dense network connectivity and strong antibiotic selective pressure, may correspond to allodemics affecting other STIs such as gonorrhea, syphilis and enteric pathogens. Collaterally, the structural and functional impact of mutations in the mgpB gene, encoding the major adhesin P140 (MgpB), may require further investigation.
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15
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Roachford O, Nelson KE, Mohapatra BR. Virulence and molecular adaptation of human urogenital mycoplasmas: a review. BIOTECHNOL BIOTEC EQ 2019. [DOI: 10.1080/13102818.2019.1607556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Affiliation(s)
- Orville Roachford
- Department of Biological and Chemical Sciences, The University of the West Indies, Cave Hill Campus, Bridgetown, Barbados
| | | | - Bidyut Ranjan Mohapatra
- Department of Biological and Chemical Sciences, The University of the West Indies, Cave Hill Campus, Bridgetown, Barbados
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16
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Dai P, Zhu Y, You X, Deng X, Zhu C, Chen L, Li L, Luo D, Zeng Y. Screening and Identification of the Binding Peptides of Mycoplasma genitalium Protein of Adhesion. Int J Pept Res Ther 2018. [DOI: 10.1007/s10989-018-9783-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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17
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Aparicio D, Torres-Puig S, Ratera M, Querol E, Piñol J, Pich OQ, Fita I. Mycoplasma genitalium adhesin P110 binds sialic-acid human receptors. Nat Commun 2018; 9:4471. [PMID: 30367053 PMCID: PMC6203739 DOI: 10.1038/s41467-018-06963-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 09/27/2018] [Indexed: 01/30/2023] Open
Abstract
Adhesion of pathogenic bacteria to target cells is a prerequisite for colonization and further infection. The main adhesins of the emerging sexually transmitted pathogen Mycoplasma genitalium, P140 and P110, interact to form a Nap complex anchored to the cell membrane. Herein, we present the crystal structures of the extracellular region of the virulence factor P110 (916 residues) unliganded and in complex with sialic acid oligosaccharides. P110 interacts only with the neuraminic acid moiety of the oligosaccharides and experiments with human cells demonstrate that these interactions are essential for mycoplasma cytadherence. Additionally, structural information provides a deep insight of the P110 antigenic regions undergoing programmed variation to evade the host immune response. These results enlighten the interplay of M. genitalium with human target cells, offering new strategies to control mycoplasma infections. How the Mycoplasma genitalium cytadhesins P140 and P110 promote host cell invasion remains poorly understood. Here, combining structural analysis with functional assays, Aparicio et al. identify the P110 domain that binds to sialylated receptors essential for mycoplasma cytadherence.
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Affiliation(s)
- David Aparicio
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Sergi Torres-Puig
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Mercè Ratera
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Enrique Querol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Jaume Piñol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Oscar Q Pich
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
| | - Ignacio Fita
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC) and Maria de Maeztu Unit of Excellence, Parc Científic de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain.
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18
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Deng X, Zhu Y, Dai P, Yu M, Chen L, Zhu C, You X, Li L, Zeng Y. Three polypeptides screened from phage display random peptide library may be the receptor polypeptide of Mycoplasma genitalium adhesion protein. Microb Pathog 2018; 120:140-146. [DOI: 10.1016/j.micpath.2018.04.058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 03/17/2018] [Accepted: 04/26/2018] [Indexed: 10/17/2022]
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19
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Seybert A, Gonzalez-Gonzalez L, Scheffer MP, Lluch-Senar M, Mariscal AM, Querol E, Matthaeus F, Piñol J, Frangakis AS. Cryo-electron tomography analyses of terminal organelle mutants suggest the motility mechanism of Mycoplasma genitalium. Mol Microbiol 2018; 108:319-329. [PMID: 29470847 DOI: 10.1111/mmi.13938] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/20/2018] [Indexed: 11/28/2022]
Abstract
The terminal organelle of Mycoplasma genitalium is responsible for bacterial adhesion, motility and pathogenicity. Localized at the cell tip, it comprises an electron-dense core that is anchored to the cell membrane at its distal end and to the cytoplasm at its proximal end. The surface of the terminal organelle is also covered with adhesion proteins. We performed cellular cryoelectron tomography on deletion mutants of eleven proteins that are implicated in building the terminal organelle, to systematically analyze the ultrastructural effects. These data were correlated with microcinematographies, from which the motility patterns can be quantitatively assessed. We visualized diverse phenotypes, ranging from mild to severe cell adhesion, motility and segregation defects. Based on our observations, we propose a double-spring ratchet model for the motility mechanism that explains our current and previous observations. Our model, which expands and integrates the previously suggested inchworm model, allocates specific functions to each of the essential components of this unique bacterial motility system.
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Affiliation(s)
- Anja Seybert
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
| | - Luis Gonzalez-Gonzalez
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Margot P Scheffer
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
| | - Maria Lluch-Senar
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Ana M Mariscal
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Enrique Querol
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Franziska Matthaeus
- Faculty of Biological Sciences & FIAS, Goethe University Frankfurt, Ruth-Moufang-Straße 1, Frankfurt 60438, Germany
| | - Jaume Piñol
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Achilleas S Frangakis
- Buchmann Institute for Molecular Life Sciences and Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
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20
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McGowin CL, Totten PA. The Unique Microbiology and Molecular Pathogenesis of Mycoplasma genitalium. J Infect Dis 2017; 216:S382-S388. [PMID: 28838077 DOI: 10.1093/infdis/jix172] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mycoplasma genitalium is increasingly appreciated as a common cause of sexually transmitted disease syndromes, including urethritis in men and cervicitis, endometritis, pelvic inflammatory disease, and possibly preterm birth, tubal factor infertility, and ectopic pregnancy in women. Despite these disease associations, which parallel those of Chlamydia trachomatis and Neisseria gonorrhoeae, the mechanisms by which this pathogen elicits inflammation, causes cellular damage, and persists in its only natural host (humans) are unique and are not fully understood. The purpose of this review is to briefly provide a historical background on the discovery, microbiology, and recognition of M. genitalium as a pathogen, and then summarize the recent advances in our understanding of the molecular biology and pathogenesis of this unique urogenital organism. Collectively, the basic scientific discussions herein should provide a framework for understanding the clinical and epidemiological outcomes described in the accompanying articles in this supplemental issue.
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Affiliation(s)
- Chris L McGowin
- Departments of 1 Microbiology, Immunology, and Parasitology.,Internal Medicine (Section of Infectious Diseases), Louisiana State University Health Sciences Center, New Orleans
| | - Patricia A Totten
- Departments of 3 Medicine (Division of Infectious Diseases).,Global Health (Pathobiology Interdisciplinary Program), University of Washington, Seattle
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21
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Tjagur S, Mändar R, Punab M. Prevalence of Mycoplasma genitalium and other sexually transmitted infections causing urethritis among high-risk heterosexual male patients in Estonia. Infect Dis (Lond) 2017; 50:133-139. [PMID: 28868962 DOI: 10.1080/23744235.2017.1366044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND We aimed to evaluate the prevalence of sexually transmitted infections (STI, including Mycoplasma genitalium, Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis) among high-risk heterosexual male patients and to clarify their potency to cause complaints and inflammation. METHODS The study group included 825 men (18.0-49.5 y) consulting andrologist at Tartu University Hospital (Estonia) due to subjectively perceived risk of STI. Patients completed STI risk behaviour questionnaire. First voided urine was analysed for white blood cells and STIs. RESULTS In total 193 (23.4%) patients were positive for one or multiple STI. The prevalence of C. trachomatis, M. genitalium, N. gonorrhoeae, T. vaginalis and combined STI was 14.3%, 4.4%, 2.7%, 0.7% and 1.3%, respectively. N. gonorrhoeae had the highest potency to generate inflammatory reaction in first voided urine (100%) followed by C. trachomatis (72.0%), M. genitalium (63.9%) and T. vaginalis (33.3%). N. gonorrhoeae and T. vaginalis caused the highest mean number of complaints while half of T. vaginalis cases and nearly fifth of M. genitalium and C. trachomatis cases were asymptomatic. CONCLUSIONS C. trachomatis has the highest prevalence among Estonian high-risk men but M. genitalium holds an important second place. Prevalence of combined STIs is low. N. gonorrhoeae has the highest potency to generate urethral inflammation followed by C. trachomatis and M. genitalium. The highest number of complaints is also associated with N. gonorrhoeae while half of T. vaginalis cases and nearly a fifth of M. genitalium and C. trachomatis cases are asymptomatic.
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Affiliation(s)
- Stanislav Tjagur
- a Tartu University Hospital, Centre of Andrology , Tartu , Estonia.,b Faculty of Medicine , University of Tartu , Tartu , Estonia
| | - Reet Mändar
- c Department of Microbiology, Faculty of Medicine , University of Tartu, Institute of Biomedicine and Translational Medicine , Tartu , Estonia.,d Competence Centre on Health Technologies , Tartu , Estonia
| | - Margus Punab
- a Tartu University Hospital, Centre of Andrology , Tartu , Estonia.,e Department of Surgery, Faculty of Medicine , University of Tartu, Institute of Clinical Medicine , Tartu , Estonia
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22
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Scheffer MP, Gonzalez-Gonzalez L, Seybert A, Ratera M, Kunz M, Valpuesta JM, Fita I, Querol E, Piñol J, Martín-Benito J, Frangakis AS. Structural characterization of the NAP; the major adhesion complex of the human pathogen Mycoplasma genitalium. Mol Microbiol 2017; 105:869-879. [PMID: 28671286 DOI: 10.1111/mmi.13743] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2017] [Indexed: 01/09/2023]
Abstract
Mycoplasma genitalium, the causative agent of non-gonococcal urethritis and pelvic inflammatory disease in humans, is a small eubacterium that lacks a peptidoglycan cell wall. On the surface of its plasma membrane is the major surface adhesion complex, known as NAP that is essential for adhesion and gliding motility of the organism. Here, we have performed cryo-electron tomography of intact cells and detergent permeabilized M. genitalium cell aggregates, providing sub-tomogram averages of free and cell-attached NAPs respectively, revealing a tetrameric complex with two-fold rotational (C2) symmetry. Each NAP has two pairs of globular lobes (named α and β lobes), arranged as a dimer of heterodimers with each lobe connected by a stalk to the cell membrane. The β lobes are larger than the α lobes by 20%. Classification of NAPs showed that the complex can tilt with respect to the cell membrane. A protein complex containing exclusively the proteins P140 and P110, was purified from M. genitalium and was structurally characterized by negative-stain single particle EM reconstruction. The close structural similarity found between intact NAPs and the isolated P140/P110 complexes, shows that dimers of P140/P110 heterodimers are the only components of the extracellular region of intact NAPs in M. genitalium.
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Affiliation(s)
- Margot P Scheffer
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
| | - Luis Gonzalez-Gonzalez
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Anja Seybert
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
| | - Mercè Ratera
- Parc Científic de Barcelona, Instituto de Biología Molecular de Barcelona del (IBMB-CSIC), Baldiri i Reixac 10, Barcelona 08028, Spain
| | - Michael Kunz
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
| | - José M Valpuesta
- Department for Macromolecular Structures, Centro Nacional de Biotecnologıa (CNB-CSIC), Madrid 28049, Spain
| | - Ignacio Fita
- Parc Científic de Barcelona, Instituto de Biología Molecular de Barcelona del (IBMB-CSIC), Baldiri i Reixac 10, Barcelona 08028, Spain
| | - Enrique Querol
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Jaume Piñol
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Jaime Martín-Benito
- Department for Macromolecular Structures, Centro Nacional de Biotecnologıa (CNB-CSIC), Madrid 28049, Spain
| | - Achilleas S Frangakis
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue Str. 15, Frankfurt 60438, Germany
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23
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Waites KB, Xiao L, Liu Y, Balish MF, Atkinson TP. Mycoplasma pneumoniae from the Respiratory Tract and Beyond. Clin Microbiol Rev 2017; 30:747-809. [PMID: 28539503 PMCID: PMC5475226 DOI: 10.1128/cmr.00114-16] [Citation(s) in RCA: 380] [Impact Index Per Article: 54.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Mycoplasma pneumoniae is an important cause of respiratory tract infections in children as well as adults that can range in severity from mild to life-threatening. Over the past several years there has been much new information published concerning infections caused by this organism. New molecular-based tests for M. pneumoniae detection are now commercially available in the United States, and advances in molecular typing systems have enhanced understanding of the epidemiology of infections. More strains have had their entire genome sequences published, providing additional insights into pathogenic mechanisms. Clinically significant acquired macrolide resistance has emerged worldwide and is now complicating treatment. In vitro susceptibility testing methods have been standardized, and several new drugs that may be effective against this organism are undergoing development. This review focuses on the many new developments that have occurred over the past several years that enhance our understanding of this microbe, which is among the smallest bacterial pathogens but one of great clinical importance.
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Affiliation(s)
- Ken B Waites
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Li Xiao
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Yang Liu
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China, and Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China
| | | | - T Prescott Atkinson
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama, USA
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The Variable Internal Structure of the Mycoplasma penetrans Attachment Organelle Revealed by Biochemical and Microscopic Analyses: Implications for Attachment Organelle Mechanism and Evolution. J Bacteriol 2017; 199:JB.00069-17. [PMID: 28373274 DOI: 10.1128/jb.00069-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 03/27/2017] [Indexed: 01/13/2023] Open
Abstract
Although mycoplasmas have small genomes, many of them, including the HIV-associated opportunist Mycoplasma penetrans, construct a polar attachment organelle (AO) that is used for both adherence to host cells and gliding motility. However, the irregular phylogenetic distribution of similar structures within the mycoplasmas, as well as compositional and ultrastructural differences among these AOs, suggests that AOs have arisen several times through convergent evolution. We investigated the ultrastructure and protein composition of the cytoskeleton-like material of the M. penetrans AO with several forms of microscopy and biochemical analysis, to determine whether the M. penetrans AO was constructed at the molecular level on principles similar to those of other mycoplasmas, such as Mycoplasma pneumoniae and Mycoplasma mobile We found that the M. penetrans AO interior was generally dissimilar from that of other mycoplasmas, in that it exhibited considerable heterogeneity in size and shape, suggesting a gel-like nature. In contrast, several of the 12 potential protein components identified by mass spectrometry of M. penetrans detergent-insoluble proteins shared certain distinctive biochemical characteristics with M. pneumoniae AO proteins, although not with M. mobile proteins. We conclude that convergence between M. penetrans and M. pneumoniae AOs extends to the molecular level, leading to the possibility that the less organized material in both M. pneumoniae and M. penetrans is the substance principally responsible for the organization and function of the AO.IMPORTANCEMycoplasma penetrans is a bacterium that infects HIV-positive patients and may contribute to the progression of AIDS. It attaches to host cells through a structure called an AO, but it is not clear how it builds this structure. Our research is significant not only because it identifies the novel protein components that make up the material within the AO that give it its structure but also because we find that the M. penetrans AO is organized unlike AOs from other mycoplasmas, suggesting that similar structures have evolved multiple times. From this work, we derive some basic principles by which mycoplasmas, and potentially all organisms, build structures at the subcellular level.
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Structural Study of MPN387, an Essential Protein for Gliding Motility of a Human-Pathogenic Bacterium, Mycoplasma pneumoniae. J Bacteriol 2016; 198:2352-9. [PMID: 27325681 DOI: 10.1128/jb.00160-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 06/17/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Mycoplasma pneumoniae is a human pathogen that glides on host cell surfaces with repeated catch and release of sialylated oligosaccharides. At a pole, this organism forms a protrusion called the attachment organelle, which is composed of surface structures, including P1 adhesin and the internal core structure. The core structure can be divided into three parts, the terminal button, paired plates, and bowl complex, aligned in that order from the front end of the protrusion. To elucidate the gliding mechanism, we focused on MPN387, a component protein of the bowl complex which is essential for gliding but dispensable for cytadherence. The predicted amino acid sequence showed that the protein features a coiled-coil region spanning residue 72 to residue 290 of the total of 358 amino acids in the protein. Recombinant MPN387 proteins were isolated with and without an enhanced yellow fluorescent protein (EYFP) fusion tag and analyzed by gel filtration chromatography, circular dichroism spectroscopy, analytical ultracentrifugation, partial proteolysis, and rotary-shadowing electron microscopy. The results showed that MPN387 is a dumbbell-shaped homodimer that is about 42.7 nm in length and 9.1 nm in diameter and includes a 24.5-nm-long central parallel coiled-coil part. The molecular image was superimposed onto the electron micrograph based on the localizing position mapped by fluorescent protein tagging. A proposed role of this protein in the gliding mechanism is discussed. IMPORTANCE Human mycoplasma pneumonia is caused by a pathogenic bacterium, Mycoplasma pneumoniae This tiny, 2-μm-long bacterium is suggested to infect humans by gliding on the surface of the trachea through binding to sialylated oligosaccharides. The mechanism underlying mycoplasma "gliding motility" is not related to any other well-studied motility systems, such as bacterial flagella and eukaryotic motor proteins. Here, we isolated and analyzed the structure of a key protein which is directly involved in the gliding mechanism.
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Miyata M, Hamaguchi T. Integrated Information and Prospects for Gliding Mechanism of the Pathogenic Bacterium Mycoplasma pneumoniae. Front Microbiol 2016; 7:960. [PMID: 27446003 PMCID: PMC4923136 DOI: 10.3389/fmicb.2016.00960] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Accepted: 06/02/2016] [Indexed: 01/21/2023] Open
Abstract
Mycoplasma pneumoniae forms a membrane protrusion at a cell pole and is known to adhere to solid surfaces, including animal cells, and can glide on these surfaces with a speed up to 1 μm per second. Notably, gliding appears to be involved in the infectious process in addition to providing the bacteria with a means of escaping the host's immune systems. However, the genome of M. pneumoniae does not encode any of the known genes found in other bacterial motility systems or any conventional motor proteins that are responsible for eukaryotic motility. Thus, further analysis of the mechanism underlying M. pneumoniae gliding is warranted. The gliding machinery formed as the membrane protrusion can be divided into the surface and internal structures. On the surface, P1 adhesin, a 170 kDa transmembrane protein forms an adhesin complex with other two proteins. The internal structure features a terminal button, paired plates, and a bowl (wheel) complex. In total, the organelle is composed of more than 15 proteins. By integrating the currently available information by genetics, microscopy, and structural analyses, we have suggested a working model for the architecture of the organelle. Furthermore, in this article, we suggest and discuss a possible mechanism of gliding based on the structural model, in which the force generated around the bowl complex transmits through the paired plates, reaching the adhesin complex, resulting in the repeated catch of sialylated oligosaccharides on the host surface by the adhesin complex.
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Affiliation(s)
- Makoto Miyata
- Department of Biology, Graduate School of Science, Osaka City UniversityOsaka, Japan; The OCU Advanced Research Institute for Natural Science and Technology, Osaka City UniversityOsaka, Japan
| | - Tasuku Hamaguchi
- Department of Biology, Graduate School of Science, Osaka City UniversityOsaka, Japan; The OCU Advanced Research Institute for Natural Science and Technology, Osaka City UniversityOsaka, Japan
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Martinelli L, García-Morales L, Querol E, Piñol J, Fita I, Calisto BM. Structure-Guided Mutations in the Terminal Organelle Protein MG491 Cause Major Motility and Morphologic Alterations on Mycoplasma genitalium. PLoS Pathog 2016; 12:e1005533. [PMID: 27082435 PMCID: PMC4833410 DOI: 10.1371/journal.ppat.1005533] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 03/07/2016] [Indexed: 11/18/2022] Open
Abstract
The emergent human pathogen Mycoplasma genitalium, with one of the smallest genomes among cells capable of growing in axenic cultures, presents a flask-shaped morphology due to a protrusion of the cell membrane, known as the terminal organelle, that is involved in cell adhesion and motility and is an important virulence factor of this microorganism. The terminal organelle is supported by a cytoskeleton complex of about 300 nm in length that includes three substructures: the terminal button, the rod and the wheel complex. The crystal structure of the MG491 protein, a proposed component of the wheel complex, has been determined at ~3 Å resolution. MG491 subunits are composed of a 60-residue N-terminus, a central three-helix-bundle spanning about 150 residues and a C-terminal region that appears to be quite flexible and contains the region that interacts with MG200, another key protein of the terminal organelle. The MG491 molecule is a tetramer presenting a unique organization as a dimer of asymmetric pairs of subunits. The asymmetric arrangement results in two very different intersubunit interfaces between the central three-helix-bundle domains, which correlates with the formation of only ~50% of the intersubunit disulfide bridges of the single cysteine residue found in MG491 (Cys87). Moreover, M. genitalium cells with a point mutation in the MG491 gene causing the change of Cys87 to Ser present a drastic reduction in motility (as determined by microcinematography) and important alterations in morphology (as determined by electron microscopy), while preserving normal levels of the terminal organelle proteins. Other variants of MG491, designed also according to the structural information, altered significantly the motility and/or the cell morphology. Together, these results indicate that MG491 plays a key role in the functioning, organization and stabilization of the terminal organelle.
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Affiliation(s)
- Luca Martinelli
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Luis García-Morales
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Enrique Querol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Jaume Piñol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Ignacio Fita
- Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Bárbara M. Calisto
- Structural Biology Group, European Synchrotron Radiation Facility, CS 40220, Grenoble, France and Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
- * E-mail:
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Periodicity in Attachment Organelle Revealed by Electron Cryotomography Suggests Conformational Changes in Gliding Mechanism of Mycoplasma pneumoniae. mBio 2016; 7:e00243-16. [PMID: 27073090 PMCID: PMC4959525 DOI: 10.1128/mbio.00243-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mycoplasma pneumoniae, a pathogenic bacterium, glides on host surfaces using a unique mechanism. It forms an attachment organelle at a cell pole as a protrusion comprised of knoblike surface structures and an internal core. Here, we analyzed the three-dimensional structure of the organelle in detail by electron cryotomography. On the surface, knoblike particles formed a two-dimensional array, albeit with limited regularity. Analyses using a nonbinding mutant and an antibody showed that the knoblike particles correspond to a naplike structure that has been observed by negative-staining electron microscopy and is likely to be formed as a complex of P1 adhesin, the key protein for binding and gliding. The paired thin and thick plates feature a rigid hexagonal lattice and striations with highly variable repeat distances, respectively. The combination of variable and invariant structures in the internal core and the P1 adhesin array on the surface suggest a model in which axial extension and compression of the thick plate along a rigid thin plate is coupled with attachment to and detachment from the substrate during gliding. Human mycoplasma pneumonia, epidemic all over the world in recent years, is caused by a pathogenic bacterium, Mycoplasma pneumoniae. This tiny bacterium, about 2 µm in cell body length, glides on the surface of the human trachea to infect the host by binding to sialylated oligosaccharides, which are also the binding targets of influenza viruses. The mechanism of mycoplasmal gliding motility is not related to any other well-studied motility systems, such as bacterial flagella and cytoplasmic motor proteins. Here, we visualized the attachment organelle, a cellular architecture for gliding, three dimensionally by using electron cryotomography and other conventional methods. A possible gliding mechanism has been suggested based on the architectural images.
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