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Gourgues G, Manso-Silván L, Chamberland C, Sirand-Pugnet P, Thiaucourt F, Blanchard A, Baby V, Lartigue C. A toolbox for manipulating the genome of the major goat pathogen, Mycoplasma capricolum subsp. capripneumoniae. MICROBIOLOGY (READING, ENGLAND) 2024; 170:001423. [PMID: 38193814 PMCID: PMC10866025 DOI: 10.1099/mic.0.001423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 12/12/2023] [Indexed: 01/10/2024]
Abstract
Mycoplasma capricolum subspecies capripneumoniae (Mccp) is the causative agent of contagious caprine pleuropneumonia (CCPP), a devastating disease listed by the World Organisation for Animal Health (WOAH) as a notifiable disease and threatening goat production in Africa and Asia. Although a few commercial inactivated vaccines are available, they do not comply with WOAH standards and there are serious doubts regarding their efficacy. One of the limiting factors to comprehend the molecular pathogenesis of CCPP and develop improved vaccines has been the lack of tools for Mccp genome engineering. In this work, key synthetic biology techniques recently developed for closely related mycoplasmas were adapted to Mccp. CReasPy-Cloning was used to simultaneously clone and engineer the Mccp genome in yeast, prior to whole-genome transplantation into M. capricolum subsp. capricolum recipient cells. This approach was used to knock out an S41 serine protease gene recently identified as a potential virulence factor, leading to the generation of the first site-specific Mccp mutants. The Cre-lox recombination system was then applied to remove all DNA sequences added during genome engineering. Finally, the resulting unmarked S41 serine protease mutants were validated by whole-genome sequencing and their non-caseinolytic phenotype was confirmed by casein digestion assay on milk agar. The synthetic biology tools that have been successfully implemented in Mccp allow the addition and removal of genes and other genetic features for the construction of seamless targeted mutants at ease, which will pave the way for both the identification of key pathogenicity determinants of Mccp and the rational design of novel, improved vaccines for the control of CCPP.
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Affiliation(s)
- Géraldine Gourgues
- Université de Bordeaux, INRAE, BFP, UMR 1332, F-33140 Villenave d'Ornon, France
| | - Lucía Manso-Silván
- CIRAD, UMR ASTRE, F-34398, Montpellier, France
- ASTRE, Université de Montpellier, CIRAD, INRAE, F-34398, Montpellier, France
| | - Catherine Chamberland
- Université de Sherbrooke, Département de biologie, Sherbrooke, Québec, J1K 2R1, Canada
| | | | - François Thiaucourt
- CIRAD, UMR ASTRE, F-34398, Montpellier, France
- ASTRE, Université de Montpellier, CIRAD, INRAE, F-34398, Montpellier, France
| | - Alain Blanchard
- Université de Bordeaux, INRAE, BFP, UMR 1332, F-33140 Villenave d'Ornon, France
| | - Vincent Baby
- Université de Montréal, Faculté de médecine vétérinaire, Saint-Hyacinthe, Québec, J2S 2M2, Canada
| | - Carole Lartigue
- Université de Bordeaux, INRAE, BFP, UMR 1332, F-33140 Villenave d'Ornon, France
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Lan S, Li Z, Hao H, Liu S, Huang Z, Bai Y, Li Y, Yan X, Gao P, Chen S, Chu Y. A genome-wide transposon mutagenesis screening identifies LppB as a key factor associated with Mycoplasma bovis colonization and invasion into host cells. FASEB J 2023; 37:e23176. [PMID: 37665592 DOI: 10.1096/fj.202300678r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 07/31/2023] [Accepted: 08/22/2023] [Indexed: 09/05/2023]
Abstract
Mycoplasma spp., the smallest self-replicating and genome-reduced organisms, have raised a great concern in both the medical and veterinary fields due to their pathogenicity. The molecular determinants of these wall-less bacterium efficiently use their limited genes to ensure successful infection of the host remain unclear. In the present study, we used the ruminant pathogen Mycoplasma bovis as a model to identify the key factors for colonization and invasion into host cells. We constructed a nonredundant fluorescent transposon mutant library of M. bovis using a modified transposon plasmid, and identified 34 novel adhesion-related genes based on a high-throughput screening approach. Among them, the ΔLppB mutant exhibited the most apparent decrease in adhesion to embryonic bovine lung (EBL) cells. The surface-localized lipoprotein LppB, which is highly conserved in Mycoplasma species, was then confirmed as a key factor for M. bovis adhesion with great immunogenicity. LppB interacted with various components (fibronectin, vitronectin, collagen IV, and laminin) of host extracellular matrix (ECM) and promoted plasminogen activation through tPA to degrade ECM. The 439-502 amino acid region of LppB is a critical domain, and F465 and Y493 are important residues for the plasminogen activation activity. We further revealed LppB as a key factor facilitating internalization through clathrin- and lipid raft-mediated endocytosis, which helps the Mycoplasma invade the host cells. Our study indicates that LppB plays a key role in Mycoplasma infection and is a potential new therapeutic and vaccine target for Mycoplasma species.
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Affiliation(s)
- Shimei Lan
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Zhangcheng Li
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Huafang Hao
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Shuang Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Zhicheng Huang
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Yutong Bai
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Yanzhao Li
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Xinmin Yan
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Pengcheng Gao
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Shengli Chen
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Yuefeng Chu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
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The Facts and Family Secrets of Plasmids That Replicate via the Rolling-Circle Mechanism. Microbiol Mol Biol Rev 2021; 86:e0022220. [PMID: 34878299 DOI: 10.1128/mmbr.00222-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Plasmids are self-replicative DNA elements that are transferred between bacteria. Plasmids encode not only antibiotic resistance genes but also adaptive genes that allow their hosts to colonize new niches. Plasmid transfer is achieved by conjugation (or mobilization), phage-mediated transduction, and natural transformation. Thousands of plasmids use the rolling-circle mechanism for their propagation (RCR plasmids). They are ubiquitous, have a high copy number, exhibit a broad host range, and often can be mobilized among bacterial species. Based upon the replicon, RCR plasmids have been grouped into several families, the best known of them being pC194 and pUB110 (Rep_1 family), pMV158 and pE194 (Rep_2 family), and pT181 and pC221 (Rep_trans family). Genetic traits of RCR plasmids are analyzed concerning (i) replication mediated by a DNA-relaxing initiator protein and its interactions with the cognate DNA origin, (ii) lagging-strand origins of replication, (iii) antibiotic resistance genes, (iv) mobilization functions, (v) replication control, performed by proteins and/or antisense RNAs, and (vi) the participating host-encoded functions. The mobilization functions include a relaxase initiator of transfer (Mob), an origin of transfer, and one or two small auxiliary proteins. There is a family of relaxases, the MOBV family represented by plasmid pMV158, which has been revisited and updated. Family secrets, like a putative open reading frame of unknown function, are reported. We conclude that basic research on RCR plasmids is of importance, and our perspectives contemplate the concept of One Earth because we should incorporate bacteria into our daily life by diminishing their virulence and, at the same time, respecting their genetic diversity.
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Blötz C, Lartigue C, Valverde Timana Y, Ruiz E, Paetzold B, Busse J, Stülke J. Development of a replicating plasmid based on the native oriC in Mycoplasma pneumoniae. MICROBIOLOGY-SGM 2018; 164:1372-1382. [PMID: 30252643 DOI: 10.1099/mic.0.000711] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacteria of the genus Mycoplasma have recently attracted considerable interest as model organisms in synthetic and systems biology. In particular, Mycoplasma pneumoniae is one of the most intensively studied organisms in the field of systems biology. However, the genetic manipulation of these bacteria is often difficult due to the lack of efficient genetic systems and some intrinsic peculiarities such as an aberrant genetic code. One major disadvantage in working with M. pneumoniae is the lack of replicating plasmids that can be used for the complementation of mutants and the expression of proteins. In this study, we have analysed the genomic region around the gene encoding the replication initiation protein, DnaA, and detected putative binding sites for DnaA (DnaA boxes) that are, however, less conserved than in other bacteria. The construction of several plasmids encompassing this region allowed the selection of plasmid pGP2756 that is stably inherited and that can be used for genetic experiments, as shown by the complementation assays with the glpQ gene encoding the glycerophosphoryl diester phosphodiesterase. Plasmid-borne complementation of the glpQ mutant restored the formation of hydrogen peroxide when bacteria were cultivated in the presence of glycerol phosphocholine. Interestingly, the replicating plasmid can also be used in the close relative, Mycoplasma genitalium but not in more distantly related members of the genus Mycoplasma. Thus, plasmid pGP2756 is a valuable tool for the genetic analysis of M. pneumoniae and M. genitalium.
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Affiliation(s)
- Cedric Blötz
- 1Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August University Göttingen, Göttingen, Germany
| | - Carole Lartigue
- 2INRA, UMR 1332 de Biologie du Fruit et Pathologie, Villenave d'Ornon, France.,3University of Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, Villenave d'Ornon, France
| | - Yanina Valverde Timana
- 2INRA, UMR 1332 de Biologie du Fruit et Pathologie, Villenave d'Ornon, France.,3University of Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, Villenave d'Ornon, France
| | - Estelle Ruiz
- 2INRA, UMR 1332 de Biologie du Fruit et Pathologie, Villenave d'Ornon, France.,3University of Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, Villenave d'Ornon, France
| | - Bernhard Paetzold
- 4Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Barcelona, Spain.,†Present address: S-Biomedic N.V., Beerse, Belgium
| | - Julia Busse
- 1Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August University Göttingen, Göttingen, Germany
| | - Jörg Stülke
- 1Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August University Göttingen, Göttingen, Germany
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Development of oriC-Based Plasmids for Mesoplasma florum. Appl Environ Microbiol 2017; 83:AEM.03374-16. [PMID: 28115382 DOI: 10.1128/aem.03374-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 01/13/2017] [Indexed: 01/06/2023] Open
Abstract
The near-minimal bacterium Mesoplasma florum constitutes an attractive model for systems biology and for the development of a simplified cell chassis in synthetic biology. However, the lack of genetic engineering tools for this microorganism has limited our capacity to understand its basic biology and modify its genome. To address this issue, we have evaluated the susceptibility of M. florum to common antibiotics and developed the first generation of artificial plasmids able to replicate in this bacterium. Selected regions of the predicted M. florum chromosomal origin of replication (oriC) were used to create different plasmid versions that were tested for their transformation frequency and stability. Using polyethylene glycol-mediated transformation, we observed that plasmids harboring both rpmH-dnaA and dnaA-dnaN intergenic regions, interspaced or not with a copy of the dnaA gene, resulted in a frequency of ∼4.1 × 10-6 transformants per viable cell and were stably maintained throughout multiple generations. In contrast, plasmids containing only one M. florumoriC intergenic region or the heterologous oriC region of Mycoplasma capricolum, Mycoplasma mycoides, or Spiroplasma citri failed to produce any detectable transformants. We also developed alternative transformation procedures based on electroporation and conjugation from Escherichia coli, reaching frequencies up to 7.87 × 10-6 and 8.44 × 10-7 transformants per viable cell, respectively. Finally, we demonstrated the functionality of antibiotic resistance genes active against tetracycline, puromycin, and spectinomycin/streptomycin in M. florum Taken together, these valuable genetic tools will facilitate efforts toward building an M. florum-based near-minimal cellular chassis for synthetic biology.IMPORTANCEMesoplasma florum constitutes an attractive model for systems biology and for the development of a simplified cell chassis in synthetic biology. M. florum is closely related to the mycoides cluster of mycoplasmas, which has become a model for whole-genome cloning, genome transplantation, and genome minimization. However, M. florum shows higher growth rates than other Mollicutes, has no known pathogenic potential, and possesses a significantly smaller genome that positions this species among some of the simplest free-living organisms. So far, the lack of genetic engineering tools has limited our capacity to understand the basic biology of M. florum in order to modify its genome. To address this issue, we have evaluated the susceptibility of M. florum to common antibiotics and developed the first artificial plasmids and transformation methods for this bacterium. This represents a strong basis for ongoing genome engineering efforts using this near-minimal microorganism.
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Suzuki Y, Assad-Garcia N, Kostylev M, Noskov VN, Wise KS, Karas BJ, Stam J, Montague MG, Hanly TJ, Enriquez NJ, Ramon A, Goldgof GM, Richter RA, Vashee S, Chuang RY, Winzeler EA, Hutchison CA, Gibson DG, Smith HO, Glass JI, Venter JC. Bacterial genome reduction using the progressive clustering of deletions via yeast sexual cycling. Genome Res 2015; 25:435-44. [PMID: 25654978 PMCID: PMC4352883 DOI: 10.1101/gr.182477.114] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The availability of genetically tractable organisms with simple genomes is critical for the rapid, systems-level understanding of basic biological processes. Mycoplasma bacteria, with the smallest known genomes among free-living cellular organisms, are ideal models for this purpose, but the natural versions of these cells have genome complexities still too great to offer a comprehensive view of a fundamental life form. Here we describe an efficient method for reducing genomes from these organisms by identifying individually deletable regions using transposon mutagenesis and progressively clustering deleted genomic segments using meiotic recombination between the bacterial genomes harbored in yeast. Mycoplasmal genomes subjected to this process and transplanted into recipient cells yielded two mycoplasma strains. The first simultaneously lacked eight singly deletable regions of the genome, representing a total of 91 genes and ∼10% of the original genome. The second strain lacked seven of the eight regions, representing 84 genes. Growth assay data revealed an absence of genetic interactions among the 91 genes under tested conditions. Despite predicted effects of the deletions on sugar metabolism and the proteome, growth rates were unaffected by the gene deletions in the seven-deletion strain. These results support the feasibility of using single-gene disruption data to design and construct viable genomes lacking multiple genes, paving the way toward genome minimization. The progressive clustering method is expected to be effective for the reorganization of any mega-sized DNA molecules cloned in yeast, facilitating the construction of designer genomes in microbes as well as genomic fragments for genetic engineering of higher eukaryotes.
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Affiliation(s)
- Yo Suzuki
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA;
| | - Nacyra Assad-Garcia
- Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
| | - Maxim Kostylev
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Vladimir N Noskov
- Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
| | - Kim S Wise
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA; Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, Missouri 65212, USA
| | - Bogumil J Karas
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Jason Stam
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Michael G Montague
- Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
| | - Timothy J Hanly
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Nico J Enriquez
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Adi Ramon
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Gregory M Goldgof
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA; University of California, San Diego, School of Medicine, La Jolla, California 92093, USA
| | - R Alexander Richter
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Sanjay Vashee
- Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
| | - Ray-Yuan Chuang
- Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
| | - Elizabeth A Winzeler
- University of California, San Diego, School of Medicine, La Jolla, California 92093, USA
| | - Clyde A Hutchison
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Daniel G Gibson
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - Hamilton O Smith
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA
| | - John I Glass
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA; Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
| | - J Craig Venter
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California 92037, USA; Synthetic Biology Group, J. Craig Venter Institute, Rockville, Maryland 20850, USA
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Aboklaish AF, Dordet-Frisoni E, Citti C, Toleman MA, Glass JI, Spiller OB. Random insertion and gene disruption via transposon mutagenesis of Ureaplasma parvum using a mini-transposon plasmid. Int J Med Microbiol 2014; 304:1218-25. [PMID: 25444567 PMCID: PMC4450083 DOI: 10.1016/j.ijmm.2014.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 09/01/2014] [Accepted: 09/21/2014] [Indexed: 01/28/2023] Open
Abstract
While transposon mutagenesis has been successfully used for Mycoplasma spp. to disrupt and determine non-essential genes, previous attempts with Ureaplasma spp. have been unsuccessful. Using a polyethylene glycol-transformation enhancing protocol, we were able to transform three separate serovars of Ureaplasma parvum with a Tn4001-based mini-transposon plasmid containing a gentamicin resistance selection marker. Despite the large degree of homology between Ureaplasma parvum and Ureaplasma urealyticum, all attempts to transform the latter in parallel failed, with the exception of a single clinical U. urealyticum isolate. PCR probing and sequencing were used to confirm transposon insertion into the bacterial genome and identify disrupted genes. Transformation of prototype serovar 3 consistently resulted in transfer only of sequence between the mini-transposon inverted repeats, but some strains showed additional sequence transfer. Transposon insertion occurred randomly in the genome resulting in unique disruption of genes UU047, UU390, UU440, UU450, UU520, UU526, UU582 for single clones from a panel of screened clones. An intergenic insertion between genes UU187 and UU188 was also characterised. Two phenotypic alterations were observed in the mutated strains: Disruption of a DEAD-box RNA helicase (UU582) altered growth kinetics, while the U. urealyticum strain lost resistance to serum attack coincident with disruption of gene UUR10_137 and loss of expression of a 41 kDa protein. Transposon mutagenesis was used successfully to insert single copies of a mini-transposon into the genome and disrupt genes leading to phenotypic changes in Ureaplasma parvum strains. This method can now be used to deliver exogenous genes for expression and determine essential genes for Ureaplasma parvum replication in culture and experimental models.
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Affiliation(s)
- Ali F Aboklaish
- Cardiff University, School of Medicine, Department of Child Health, 5th floor University Hospital of Wales, Cardiff CF14 4XN, UK; Sebha University, Faculty of Engineering and Technology, Medical Laboratory Sciences Department, PO Box 68, Libya
| | - Emilie Dordet-Frisoni
- INRA, UMR 1225, IHAP, 31076 Toulouse, France; Université de Toulouse, INP, ENVT, UMR1225, IHAP, 31076 Toulouse, France
| | - Christine Citti
- INRA, UMR 1225, IHAP, 31076 Toulouse, France; Université de Toulouse, INP, ENVT, UMR1225, IHAP, 31076 Toulouse, France
| | - Mark A Toleman
- Cardiff University, School of Medicine, Institute of Infection and Immunity, Cardiff CF14 4XN, UK
| | | | - O Brad Spiller
- Cardiff University, School of Medicine, Department of Child Health, 5th floor University Hospital of Wales, Cardiff CF14 4XN, UK.
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Breton M, Tardy F, Dordet-Frisoni E, Sagne E, Mick V, Renaudin J, Sirand-Pugnet P, Citti C, Blanchard A. Distribution and diversity of mycoplasma plasmids: lessons from cryptic genetic elements. BMC Microbiol 2012; 12:257. [PMID: 23145790 PMCID: PMC3541243 DOI: 10.1186/1471-2180-12-257] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 11/05/2012] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The evolution of mycoplasmas from a common ancestor with Firmicutes has been characterized not only by genome down-sizing but also by horizontal gene transfer between mycoplasma species sharing a common host. The mechanisms of these gene transfers remain unclear because our knowledge of the mycoplasma mobile genetic elements is limited. In particular, only a few plasmids have been described within the Mycoplasma genus. RESULTS We have shown that several species of ruminant mycoplasmas carry plasmids that are members of a large family of elements and replicate via a rolling-circle mechanism. All plasmids were isolated from species that either belonged or were closely related to the Mycoplasma mycoides cluster; none was from the Mycoplasma bovis-Mycoplasma agalactiae group. Twenty one plasmids were completely sequenced, named and compared with each other and with the five mycoplasma plasmids previously reported. All plasmids share similar size and genetic organization, and present a mosaic structure. A peculiar case is that of the plasmid pMyBK1 from M. yeatsii; it is larger in size and is predicted to be mobilizable. Its origin of replication and replication protein were identified. In addition, pMyBK1 derivatives were shown to replicate in various species of the M. mycoides cluster, and therefore hold considerable promise for developing gene vectors. The phylogenetic analysis of these plasmids confirms the uniqueness of pMyBK1 and indicates that the other mycoplasma plasmids cluster together, apart from the related replicons found in phytoplasmas and in species of the clade Firmicutes. CONCLUSIONS Our results unraveled a totally new picture of mycoplasma plasmids. Although they probably play a limited role in the gene exchanges that participate in mycoplasma evolution, they are abundant in some species. Evidence for the occurrence of frequent genetic recombination strongly suggests they are transmitted between species sharing a common host or niche.
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Affiliation(s)
- Marc Breton
- University Bordeaux, UMR 1332 Biologie du Fruit et Pathologie, 71 avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
- INRA, UMR 1332 Biologie du Fruit et Pathologie, 71, avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
| | - Florence Tardy
- Anses, Laboratoire de Lyon, UMR Mycoplasmoses des Ruminants, 31 Avenue Tony Garnier, F-69364, Lyon cedex 07, France
| | - Emilie Dordet-Frisoni
- INRA, UMR1225, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, F-31076, Toulouse Cedex 3, France
- Université de Toulouse, INP-ENVT, UMR1225, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, F-31076, Toulouse Cedex 3, France
| | - Eveline Sagne
- INRA, UMR1225, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, F-31076, Toulouse Cedex 3, France
- Université de Toulouse, INP-ENVT, UMR1225, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, F-31076, Toulouse Cedex 3, France
| | - Virginie Mick
- Anses, Laboratoire de Lyon, UMR Mycoplasmoses des Ruminants, 31 Avenue Tony Garnier, F-69364, Lyon cedex 07, France
| | - Joël Renaudin
- University Bordeaux, UMR 1332 Biologie du Fruit et Pathologie, 71 avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
- INRA, UMR 1332 Biologie du Fruit et Pathologie, 71, avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
| | - Pascal Sirand-Pugnet
- University Bordeaux, UMR 1332 Biologie du Fruit et Pathologie, 71 avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
- INRA, UMR 1332 Biologie du Fruit et Pathologie, 71, avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
| | - Christine Citti
- INRA, UMR1225, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, F-31076, Toulouse Cedex 3, France
- Université de Toulouse, INP-ENVT, UMR1225, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, F-31076, Toulouse Cedex 3, France
| | - Alain Blanchard
- University Bordeaux, UMR 1332 Biologie du Fruit et Pathologie, 71 avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
- INRA, UMR 1332 Biologie du Fruit et Pathologie, 71, avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France
- Centre INRA de Bordeaux Aquitaine, UMR 1332 Biologie du Fruit et Pathologie, 71, avenue Edouard Bourlaux, BP81, F-33140, Villenave d'Ornon, France
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9
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Benders GA, Noskov VN, Denisova EA, Lartigue C, Gibson DG, Assad-Garcia N, Chuang RY, Carrera W, Moodie M, Algire MA, Phan Q, Alperovich N, Vashee S, Merryman C, Venter JC, Smith HO, Glass JI, Hutchison CA. Cloning whole bacterial genomes in yeast. Nucleic Acids Res 2010; 38:2558-69. [PMID: 20211840 PMCID: PMC2860123 DOI: 10.1093/nar/gkq119] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 02/08/2010] [Accepted: 02/09/2010] [Indexed: 01/21/2023] Open
Abstract
Most microbes have not been cultured, and many of those that are cultivatable are difficult, dangerous or expensive to propagate or are genetically intractable. Routine cloning of large genome fractions or whole genomes from these organisms would significantly enhance their discovery and genetic and functional characterization. Here we report the cloning of whole bacterial genomes in the yeast Saccharomyces cerevisiae as single-DNA molecules. We cloned the genomes of Mycoplasma genitalium (0.6 Mb), M. pneumoniae (0.8 Mb) and M. mycoides subspecies capri (1.1 Mb) as yeast circular centromeric plasmids. These genomes appear to be stably maintained in a host that has efficient, well-established methods for DNA manipulation.
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Affiliation(s)
- Gwynedd A Benders
- Synthetic Biology and Bioenergy Group, The J. Craig Venter Institute, San Diego, CA 92121, USA.
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10
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Lartigue C, Vashee S, Algire MA, Chuang RY, Benders GA, Ma L, Noskov VN, Denisova EA, Gibson DG, Assad-Garcia N, Alperovich N, Thomas DW, Merryman C, Hutchison CA, Smith HO, Venter JC, Glass JI. Creating Bacterial Strains from Genomes That Have Been Cloned and Engineered in Yeast. Science 2009; 325:1693-6. [PMID: 19696314 DOI: 10.1126/science.1173759] [Citation(s) in RCA: 202] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Carole Lartigue
- J. Craig Venter Institute, 9704 Medical Center Drive, Rockville, MD 20850, USA
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11
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New selectable marker for manipulating the simple genomes of Mycoplasma species. Antimicrob Agents Chemother 2009; 53:4429-32. [PMID: 19687239 DOI: 10.1128/aac.00388-09] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Over the past several years, significant advances have been made in the molecular genetics of the Mollicutes (the simplest cells that can be grown in axenic culture). Nevertheless, a number of basic molecular tools are still required before genetic manipulations become routine. Here we describe the development of a new dominant selectable marker based on the enzyme puromycin-N-acetyltransferase from Streptomyces alboniger. Puromycin is an antibiotic that mimics the 3'-terminal end of aminoacylated tRNAs and attaches to the carboxyl terminus of growing protein chains. This stops protein synthesis. Because puromycin conscripts rRNA recognition elements that are used by all of the various tRNAs in a cell, it is unlikely that spontaneous antibiotic resistance can be acquired via a simple point mutation--an annoying issue with existing mycoplasma markers. Our codon-optimized cassette confers pronounced puromycin resistance on all five of the mycoplasma species we have tested so far. The resistance cassette was also designed to function in Escherichia coli, which simplifies the construction of shuttle vectors and makes it trivial to produce the large quantities of DNA generally necessary for mycoplasma transformation. Due to these and other features, we expect the puromycin marker to be a widely applicable tool for studying these simple cells and pathogens.
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12
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Janis C, Bischof D, Gourgues G, Frey J, Blanchard A, Sirand-Pugnet P. Unmarked insertional mutagenesis in the bovine pathogen Mycoplasma mycoides subsp. mycoides SC: characterization of a lppQ mutant. MICROBIOLOGY (READING, ENGLAND) 2008; 154:2427-2436. [PMID: 18667575 PMCID: PMC2628567 DOI: 10.1099/mic.0.2008/017640-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mycoplasma mycoides subspecies mycoides small colony (SC) is the aetiologic agent of contagious bovine pleuropneumonia (CBPP), a respiratory disease causing important losses in cattle production. The publication of the genome sequence of M. mycoides subsp. mycoides SC should facilitate the identification of putative virulence factors. However, real progress in the study of molecular mechanisms of pathogenicity also requires efficient molecular tools for gene inactivation. In the present study, we have developed a transposon-based approach for the random mutagenesis of M. mycoides subsp. mycoides SC. A PCR-based screening assay enabled the characterization of several mutants with knockouts of genes potentially involved in pathogenicity. The initial transposon was further improved by combining it with the transposon gammadelta TnpR/res recombination system to allow the production of unmarked mutations. Using this approach, we isolated a mutant free of antibiotic-resistance genes, in which the gene encoding the main lipoprotein LppQ was disrupted. The mutant was found to express only residual amounts of the truncated N-terminal end of LppQ. This approach opens the way to study virulence factors and pathogen-host interactions of M. mycoides subsp. mycoides SC and to develop new, genetically defined vaccine strains.
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Affiliation(s)
- Carole Janis
- INRA, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
- Université Victor Segalen Bordeaux 2, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
| | - Daniela Bischof
- Institute of Veterinary Bacteriology, Universität Bern, Laenggassstrasse 122, CH-3012 Berne, Switzerland
| | - Géraldine Gourgues
- INRA, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
- Université Victor Segalen Bordeaux 2, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
| | - Joachim Frey
- Institute of Veterinary Bacteriology, Universität Bern, Laenggassstrasse 122, CH-3012 Berne, Switzerland
| | - Alain Blanchard
- INRA, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
- Université Victor Segalen Bordeaux 2, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
| | - Pascal Sirand-Pugnet
- INRA, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
- Université Victor Segalen Bordeaux 2, UMR 1090, 71 avenue Edouard Bourlaux, F-33140 Villenave d’Ornon, France
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13
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Abstract
There are few systems available for studying the genetics of the important avian respiratory pathogen, Mycoplasma gallisepticum. These techniques are needed to develop a mechanism to study the molecular pathogenesis of M. gallisepticum. Tn916 has the ability to transpose into the M. gallisepticum genome by both transformation and conjugation. In this study, PEG-mediated transformation was employed for the transfer of Tn916 into M. gallisepticum and create a transposon mutant library. Transformants were obtained at a frequency of approximately 5 x 10(-8) per recipient CFU. A total of 424 MG/Tn916 mutants were constructed and sequence data from the transposon junctions of 71 mutants was obtained and used to identify transposon insertion sites. Insertions were found throughout the genome in nearly all of the major gene categories, making this the first extensive characterization of a transposon mutant library of M. gallisepticum. Transposon stability was also examined, and it was determined that for two mutants the element was stably maintained in vivo in the absence of selective pressure.
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Affiliation(s)
- Patricia L Whetzel
- Department of Animal and Food Sciences, College of Agriculture and Natural Resources, University of Delaware, Newark, DE 19717-1303, USA
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14
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Cordova CMM, Lartigue C, Sirand-Pugnet P, Renaudin J, Cunha RAF, Blanchard A. Identification of the origin of replication of the Mycoplasma pulmonis chromosome and its use in oriC replicative plasmids. J Bacteriol 2002; 184:5426-35. [PMID: 12218031 PMCID: PMC135349 DOI: 10.1128/jb.184.19.5426-5435.2002] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2002] [Accepted: 07/10/2002] [Indexed: 11/20/2022] Open
Abstract
Mycoplasma pulmonis is a natural rodent pathogen, considered a privileged model for studying respiratory mycoplasmosis. The complete genome of this bacterium, which belongs to the class Mollicutes, has recently been sequenced, but studying the role of specific genes requires improved genetic tools. In silico comparative analysis of sequenced mollicute genomes indicated the lack of conservation of gene order in the region containing the predicted origin of replication (oriC) and the existence, in most of the mollicute genomes examined, of putative DnaA boxes lying upstream and downstream from the dnaA gene. The predicted M. pulmonis oriC region was shown to be functional after cloning it into an artificial plasmid and after transformation of the mycoplasma, which was obtained with a frequency of 3 x 10(-6) transformants/CFU/ micro g of plasmid DNA. However, after a few in vitro passages, this plasmid integrated into the chromosomal oriC region. Reduction of this oriC region by subcloning experiments to the region either upstream or downstream from dnaA resulted in plasmids that failed to replicate in M. pulmonis, except when these two intergenic regions were cloned with the tetM determinant as a spacer in between them. An internal fragment of the M. pulmonis hemolysin A gene (hlyA) was cloned into this oriC plasmid, and the resulting construct was used to transform M. pulmonis. Targeted integration of this genetic element into the chromosomal hlyA by a single crossing over, which results in the disruption of the gene, could be documented. These mycoplasmal oriC plasmids may therefore become valuable tools for investigating the roles of specific genes, including those potentially implicated in pathogenesis.
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Affiliation(s)
- Caio M M Cordova
- University of Sao Paulo, Analises Clinica & Toxicologicas, Faculdade de Ciencias Farmaceuticas, Sao Paulo 05508-900, Brazil
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15
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Papazisi L, Troy KE, Gorton TS, Liao X, Geary SJ. Analysis of cytadherence-deficient, GapA-negative Mycoplasma gallisepticum strain R. Infect Immun 2000; 68:6643-9. [PMID: 11083776 PMCID: PMC97761 DOI: 10.1128/iai.68.12.6643-6649.2000] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Comparison of the phenotypic expression of Mycoplasma gallisepticum strain R low (passage 15) to that of strain R high (passage 164) revealed that three proteins, i.e., the cytadhesin molecule GapA, a 116-kDa protein (p116), and a 45-kDa protein (p45), are missing in strain R high. Sequence analysis confirmed that the insertion of an adenine 105 bp downstream of the gapA translational start codon resulted in premature termination of translation in R high. A second adenine insertion had also occurred at position 907. Restoration of expression of wild-type gapA in R high (clone designated GT5) allowed us to evaluate the extent to which the diminished cytadherence capacity could be attributed to GapA alone. The results indicated that GT5 attached to the same limited extent as the parental R high, from which it was derived. The cytadherence capability of the parental R high was not restored solely by gapA complementation alone, indicating that either p116 or p45 or both may play a role in the overall cytadherence process. The gene encoding p116 was found to be immediately downstream of gapA in the same operon and was designated crmA. This gene exhibited striking homology to genes encoding molecules with cytadhesin-related functions in both Mycoplasma pneumoniae and Mycoplasma genitalium. Transcriptional analysis revealed that crmA is not transcribed in R high. We are currently constructing a shuttle vector containing both the wild-type gapA and crmA for transformation into R high to assess the role of CrmA in the cytadherence process.
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Affiliation(s)
- L Papazisi
- Department of Pathobiology and Center of Excellence for Vaccine Research, The University of Connecticut, Storrs, Connecticut 06269-3089, USA
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16
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17
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Abstract
The recent sequencing of the entire genomes of Mycoplasma genitalium and M. pneumoniae has attracted considerable attention to the molecular biology of mycoplasmas, the smallest self-replicating organisms. It appears that we are now much closer to the goal of defining, in molecular terms, the entire machinery of a self-replicating cell. Comparative genomics based on comparison of the genomic makeup of mycoplasmal genomes with those of other bacteria, has opened new ways of looking at the evolutionary history of the mycoplasmas. There is now solid genetic support for the hypothesis that mycoplasmas have evolved as a branch of gram-positive bacteria by a process of reductive evolution. During this process, the mycoplasmas lost considerable portions of their ancestors' chromosomes but retained the genes essential for life. Thus, the mycoplasmal genomes carry a high percentage of conserved genes, greatly facilitating gene annotation. The significant genome compaction that occurred in mycoplasmas was made possible by adopting a parasitic mode of life. The supply of nutrients from their hosts apparently enabled mycoplasmas to lose, during evolution, the genes for many assimilative processes. During their evolution and adaptation to a parasitic mode of life, the mycoplasmas have developed various genetic systems providing a highly plastic set of variable surface proteins to evade the host immune system. The uniqueness of the mycoplasmal systems is manifested by the presence of highly mutable modules combined with an ability to expand the antigenic repertoire by generating structural alternatives, all compressed into limited genomic sequences. In the absence of a cell wall and a periplasmic space, the majority of surface variable antigens in mycoplasmas are lipoproteins. Apart from providing specific antimycoplasmal defense, the host immune system is also involved in the development of pathogenic lesions and exacerbation of mycoplasma induced diseases. Mycoplasmas are able to stimulate as well as suppress lymphocytes in a nonspecific, polyclonal manner, both in vitro and in vivo. As well as to affecting various subsets of lymphocytes, mycoplasmas and mycoplasma-derived cell components modulate the activities of monocytes/macrophages and NK cells and trigger the production of a wide variety of up-regulating and down-regulating cytokines and chemokines. Mycoplasma-mediated secretion of proinflammatory cytokines, such as tumor necrosis factor alpha, interleukin-1 (IL-1), and IL-6, by macrophages and of up-regulating cytokines by mitogenically stimulated lymphocytes plays a major role in mycoplasma-induced immune system modulation and inflammatory responses.
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Affiliation(s)
- S Razin
- Department of Membrane and Ultrastructure Research, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
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18
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Abstract
Although mycoplasmas lack cell walls, they are in many respects similar to the gram-positive bacteria with which they share a common ancestor. The molecular biology of mycoplasmas is intriguing because the chromosome is uniquely small (< 600 kb in some species) and extremely A-T rich (as high as 75 mol% in some species). Perhaps to accommodate DNA with a lower G + C content, most mycoplasmas do not have the "universal" genetic code. In these species, TGA is not a stop codon; instead it encodes tryptophan at a frequency 10 times greater than TGG, the usual codon for this amino acid. Because of the presence of TGA codons, the translation of mycoplasmal proteins terminates prematurely when cloned genes are expressed in other eubacteria, such as Escherichia coli. Many mycoplasmas possess strikingly dynamic chromosomes in which high-frequency changes result from errors in DNA repair or replication and from highly active recombination systems. Often, high-frequency changes in the mycoplasmal chromosome are associated with antigenic and phase variation, which regulate the production of factors critical to disease pathogenesis.
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Affiliation(s)
- K Dybvig
- Department of Comparative Medicine, University of Alabama at Birmingham 35294, USA
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19
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Voelker LL, Dybvig K. Gene transfer in Mycoplasma arthritidis: transformation, conjugal transfer of Tn916, and evidence for a restriction system recognizing AGCT. J Bacteriol 1996; 178:6078-81. [PMID: 8830712 PMCID: PMC178472 DOI: 10.1128/jb.178.20.6078-6081.1996] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Mycoplasma arthritidis is a rat pathogen causing a severe polyarthritis. The study of its pathogenic mechanisms has been hampered by the lack of genetic systems for use with M. arthritidis. Described here are procedures for genetic transformation of M. arthritidis and conjugal transfer of Tn916 from an enterococcal donor to M. arthritidis. The location of Tn916 insertion sites in the mycoplasmal chromosome was random, suggesting that Tn916 may be useful as an insertional mutagen in this organism. Additionally, a restriction and modification system was identified which presented a strong barrier to gene transfer. For transformation, the restriction system was circumvented by using DNA that was modified in vitro with the appropriate site-specific methylase (AluI).
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Affiliation(s)
- L L Voelker
- Department of Comparative Medicine, University of Alabama at Birmingham, 35294-0019, USA
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20
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Nicholas RA, Bashiruddin JB. Mycoplasma mycoides subspecies mycoides (small colony variant): the agent of contagious bovine pleuropneumonia and member of the "Mycoplasma mycoides cluster". J Comp Pathol 1995; 113:1-27. [PMID: 7490334 DOI: 10.1016/s0021-9975(05)80065-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- R A Nicholas
- Central Veterinary Laboratory, New Haw, Addlestone, Surrey, United Kingdom
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21
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Cao J, Kapke PA, Minion FC. Transformation of Mycoplasma gallisepticum with Tn916, Tn4001, and integrative plasmid vectors. J Bacteriol 1994; 176:4459-62. [PMID: 8021232 PMCID: PMC205662 DOI: 10.1128/jb.176.14.4459-4462.1994] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Mycoplasma gallisepticum causes respiratory disease in avian species, but little is known about its mechanism(s) of pathogenesis. These studies were undertaken in order to develop genetic systems for analysis of potential virulence factors. M. gallisepticum was transformed with plasmids containing one of the gram-positive transposons Tn916 or Tn4001, which inserted randomly into the mycoplasmal chromosome. Plasmids containing cloned chromosomal DNA were also constructed and tested for integration into regions of DNA homology derived either from chromosomal fragments or from the gentamicin resistance marker from Tn4001. These studies demonstrate that M. gallisepticum is amenable to transformation with both transposons and integrative vectors.
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Affiliation(s)
- J Cao
- Department of Micrlbiology, Immunology and Preventive Medicine, Iowa State University, Ames 50011
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22
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Bhugra B, Dybvig K. Identification and characterization of IS1138, a transposable element from Mycoplasma pulmonis that belongs to the IS3 family. Mol Microbiol 1993; 7:577-84. [PMID: 8096321 DOI: 10.1111/j.1365-2958.1993.tb01148.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Insertion sequence (IS) elements are mobile genetic elements found in prokaryotes. We have identified a repetitive element from Mycoplasma pulmonis, a murine pathogen, that is similar to eubacterial IS elements. By subcloning a single strain of M. pulmonis, we isolated a variant clone in which the IS element had undergone an apparent transposition event. The nucleotide sequences of the element, designated IS1138, and the target site into which it inserted were determined. IS1138 consists of 1288 bp with 18 bp perfect terminal inverted repeats. Sequence analysis of the target site before and after insertion of IS1138 identified a 3 bp duplication of target DNA flanking the element. The predicted amino acids encoded by the major open reading frame of IS1138 share significant similarity with the transposases of the IS3 family. Southern hybridization analysis indicates that repetitive sequences similar to IS1138 are present in most, if not all, strains of M. pulmonis, but IS1138-like sequences were not detected in other mycoplasmal species.
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Affiliation(s)
- B Bhugra
- Department of Microbiology, University of Alabama, Birmingham 35294
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23
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Abstract
To facilitate the development of mycoplasmal cloning vectors, we have determined the nucleotide sequence of pKMK1, a cryptic plasmid isolated from Mycoplasma mycoides subsp. mycoides. It is 1875 bp in length and contains two open reading frames (ORFs) that share homology with ORFs from members of a large family of gram-positive bacterial plasmids which replicate via a single-stranded DNA intermediate. Putative origins of replication and candidate cloning sites have been identified.
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Affiliation(s)
- K W King
- Department of Microbiology, University of Alabama, Birmingham 35294
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