The Experts below are selected from a list of 3177 Experts worldwide ranked by ideXlab platform
Colette Saillard - One of the best experts on this subject based on the ideXlab platform.
-
entry of spiroplasma citri into circulifer haematoceps cells involves interaction between spiroplasma phosphoglycerate kinase and leafhopper actin
Applied and Environmental Microbiology, 2010Co-Authors: Fabien Labroussaa, Nathalie Arricaubouvery, Mariepierre Dubrana, Colette SaillardAbstract:Transmission of the phytopathogenic Mollicutes, spiroplasmas, and phytoplasmas by their insect vectors mainly depends on their ability to pass through gut cells, to multiply in various tissues, and to traverse the salivary gland cells. The passage of these different barriers suggests molecular interactions between the plant mollicute and the insect vector that regulate transmission. In the present study, we focused on the interaction between Spiroplasma citri and its leafhopper vector, Circulifer haematoceps. An in vitro protein overlay assay identified five significant binding activities between S. citri proteins and insect host proteins from salivary glands. One insect protein involved in one binding activity was identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as actin. Confocal microscopy observations of infected salivary glands revealed that spiroplasmas colocated with the host actin filaments. An S. citri actin-binding protein of 44 kDa was isolated by affinity chromatography and identified by LC-MS/MS as phosphoglycerate kinase (PGK). To investigate the role of the PGK-actin interaction, we performed competitive binding and internalization assays on leafhopper cultured cell lines (Ciha-1) in which His6-tagged PGK from S. citri or purified PGK from Saccharomyces cerevisiae was added prior to the addition of S. citri inoculum. The results suggested that exogenous PGK has no effect on spiroplasmal attachment to leafhopper cell surfaces but inhibits S. citri internalization, demonstrating that the process leading to internalization of S. citri in eukaryotic cells requires the presence of PGK. PGK, regardless of origin, reduced the entry of spiroplasmas into Ciha-1 cells in a dose-dependent manner.
-
the abundant extrachromosomal dna content of the spiroplasma citri gii3 3x genome
BMC Genomics, 2008Co-Authors: Colette Saillard, Patricia Carle, Raphael Henri, Nabil Killiny, Sebastien Carrere, Jerome Gouzy, Joël Renaudin, Sybille Duretnurbel, Josephmarie Bove, Xavier FoissacAbstract:Background Spiroplama citri, the causal agent of citrus stubborn disease, is a bacterium of the class Mollicutes and is transmitted by phloem-feeding leafhopper vectors. In order to characterize candidate genes potentially involved in spiroplasma transmission and pathogenicity, the genome of S. citri strain GII3-3X is currently being deciphered.
-
spiroplasma citri a plant pathogenic mollicute relationships with its two hosts the plant and the leafhopper vector
Annual Review of Phytopathology, 2003Co-Authors: Joseph M. Bové, Colette Saillard, Joël Renaudin, Xavier Foissac, Monique GarnierAbstract:▪ Abstract Spiroplasma citri, the type species of the genus Spiroplasma (Spiroplasmataceae, Mollicutes), is restricted to the phloem sieve tubes and transmitted by phloem sap-feeding insects, as is characteristic of the phytopathogenic Mollicutes. The spiroplasmas are the only Mollicutes showing motility and helical morphology, apparently mediated by a contractile fibrillar cytoskeleton bound to the inner surface of the spiroplasmal membrane. MreB genes, which are involved in cell-shape determination, have been identified in S. citri. Identified genes of other functional groups are those involved in the transmission of S. citri by the leafhoppers and genes coding for lipoproteins, including spiralin, bound to the outer surface of the spiroplasma membrane. S. citri mutants that are unable to use fructose induce only mild and delayed symptoms. Fructose utilization by the sieve tube-restricted wild-type spiroplasmas is postulated to deprive the companion cells of fructose, thereby impairing sucrose loading i...
-
Effect of Polyclonal, Monoclonal, and Recombinant (Single-Chain Variable Fragment) Antibodies on In Vitro Morphology, Growth, and Metabolism of the Phytopathogenic Mollicute Spiroplasma citri
Applied and Environmental Microbiology, 2002Co-Authors: Sylvie Malembic, Colette Saillard, Joseph M. Bové, Monique GarnierAbstract:Antibodies are known to affect the morphology, growth, and metabolism of Mollicutes and thus may serve as candidate molecules for a plantibody-based control strategy for plant-pathogenic spiroplasmas and phytoplasmas. Recombinant single-chain variable fragment (scFv) antibodies are easy to engineer and express in plants, but their inhibitory effects on Mollicutes have never been evaluated and compared with those of polyclonal and monoclonal antibodies. We describe the morphology, growth, and glucose metabolism of Spiroplasma citri in the presence of polyclonal, monoclonal, and recombinant antibodies directed against the immunodominant membrane protein spiralin. We showed that the scFv antibodies had no effect on S. citri glucose metabolism but were as efficient as polyclonal antibodies in inhibiting S. citri growth in liquid medium. Inhibition of motility was also observed.
-
Effect of Polyclonal, Monoclonal, and Recombinant (Single-Chain Variable Fragment) Antibodies on In Vitro Morphology, Growth, and
2001Co-Authors: Metabolism Phytopathogenic, Colette Saillard, Sylvie Malembic, Joseph M. Bové, Mollicute Spiroplasma, Monique GarnierAbstract:Antibodies are known to affect the morphology, growth, and metabolism of Mollicutes and thus may serve as candidate molecules for a plantibody-based control strategy for plant-pathogenic spiroplasmas and phyto-plasmas. Recombinant single-chain variable fragment (scFv) antibodies are easy to engineer and express in plants, but their inhibitory effects on Mollicutes have never been evaluated and compared with those of polyclonal and monoclonal antibodies. We describe the morphology, growth, and glucose metabolism of Spiroplasma citri in the presence of polyclonal, monoclonal, and recombinant antibodies directed against the immunodominant membrane protein spiralin. We showed that the scFv antibodies had no effect on S. citri glucose metabolism but were as efficient as polyclonal antibodies in inhibiting S. citri growth in liquid medium. Inhibition of motility was also observed. Plant-pathogenic Mollicutes include the genus Spiroplasma, comprising organisms culturable in complex artificial media and showing a helical morphology, and the Candidatus genus phytoplasma, containing large numbers of pleiomorphic organ-isms which, until now, have resisted in vitro cultivation (4, 9). Hence, spiroplasmas are the most-studied phytopathogenic Mollicutes, and S. citri (23) is the model organism for this important group of plant pathogens. Mollicutes are eubacteria without a cell wall and thus de-limited only by a cytoplasmic membrane. This characteristic has been linked with the fact that metabolism and growth of Mollicutes were strongly inhibited by antibodies directe
Monique Garnier - One of the best experts on this subject based on the ideXlab platform.
-
spiroplasma citri a plant pathogenic mollicute relationships with its two hosts the plant and the leafhopper vector
Annual Review of Phytopathology, 2003Co-Authors: Joseph M. Bové, Colette Saillard, Joël Renaudin, Xavier Foissac, Monique GarnierAbstract:▪ Abstract Spiroplasma citri, the type species of the genus Spiroplasma (Spiroplasmataceae, Mollicutes), is restricted to the phloem sieve tubes and transmitted by phloem sap-feeding insects, as is characteristic of the phytopathogenic Mollicutes. The spiroplasmas are the only Mollicutes showing motility and helical morphology, apparently mediated by a contractile fibrillar cytoskeleton bound to the inner surface of the spiroplasmal membrane. MreB genes, which are involved in cell-shape determination, have been identified in S. citri. Identified genes of other functional groups are those involved in the transmission of S. citri by the leafhoppers and genes coding for lipoproteins, including spiralin, bound to the outer surface of the spiroplasma membrane. S. citri mutants that are unable to use fructose induce only mild and delayed symptoms. Fructose utilization by the sieve tube-restricted wild-type spiroplasmas is postulated to deprive the companion cells of fructose, thereby impairing sucrose loading i...
-
Effect of Polyclonal, Monoclonal, and Recombinant (Single-Chain Variable Fragment) Antibodies on In Vitro Morphology, Growth, and Metabolism of the Phytopathogenic Mollicute Spiroplasma citri
Applied and Environmental Microbiology, 2002Co-Authors: Sylvie Malembic, Colette Saillard, Joseph M. Bové, Monique GarnierAbstract:Antibodies are known to affect the morphology, growth, and metabolism of Mollicutes and thus may serve as candidate molecules for a plantibody-based control strategy for plant-pathogenic spiroplasmas and phytoplasmas. Recombinant single-chain variable fragment (scFv) antibodies are easy to engineer and express in plants, but their inhibitory effects on Mollicutes have never been evaluated and compared with those of polyclonal and monoclonal antibodies. We describe the morphology, growth, and glucose metabolism of Spiroplasma citri in the presence of polyclonal, monoclonal, and recombinant antibodies directed against the immunodominant membrane protein spiralin. We showed that the scFv antibodies had no effect on S. citri glucose metabolism but were as efficient as polyclonal antibodies in inhibiting S. citri growth in liquid medium. Inhibition of motility was also observed.
-
Effect of Polyclonal, Monoclonal, and Recombinant (Single-Chain Variable Fragment) Antibodies on In Vitro Morphology, Growth, and
2001Co-Authors: Metabolism Phytopathogenic, Colette Saillard, Sylvie Malembic, Joseph M. Bové, Mollicute Spiroplasma, Monique GarnierAbstract:Antibodies are known to affect the morphology, growth, and metabolism of Mollicutes and thus may serve as candidate molecules for a plantibody-based control strategy for plant-pathogenic spiroplasmas and phyto-plasmas. Recombinant single-chain variable fragment (scFv) antibodies are easy to engineer and express in plants, but their inhibitory effects on Mollicutes have never been evaluated and compared with those of polyclonal and monoclonal antibodies. We describe the morphology, growth, and glucose metabolism of Spiroplasma citri in the presence of polyclonal, monoclonal, and recombinant antibodies directed against the immunodominant membrane protein spiralin. We showed that the scFv antibodies had no effect on S. citri glucose metabolism but were as efficient as polyclonal antibodies in inhibiting S. citri growth in liquid medium. Inhibition of motility was also observed. Plant-pathogenic Mollicutes include the genus Spiroplasma, comprising organisms culturable in complex artificial media and showing a helical morphology, and the Candidatus genus phytoplasma, containing large numbers of pleiomorphic organ-isms which, until now, have resisted in vitro cultivation (4, 9). Hence, spiroplasmas are the most-studied phytopathogenic Mollicutes, and S. citri (23) is the model organism for this important group of plant pathogens. Mollicutes are eubacteria without a cell wall and thus de-limited only by a cytoplasmic membrane. This characteristic has been linked with the fact that metabolism and growth of Mollicutes were strongly inhibited by antibodies directe
Joseph M. Bové - One of the best experts on this subject based on the ideXlab platform.
-
Avian Pathogen, Mycoplasma iowae, and Its Implications for Mollicute Taxonomy
2013Co-Authors: David L. Rose, Joseph M. BovéAbstract:Strain PPAV, a filamentous but nonhelical mollicute, was isolated from aborted apple seeds in France in late 1979. This organism grew well in SP-4 broth, fermented glucose, and required sterol for growth, and most of its properties suggested that it belonged to the genus Mycoplasma. However, it was serologically distinct; in addition, unlike other Mycoplasma species, genome measurements consistently yielded values of about 1,000 MDa (ca. 1,500 kbp), and the organism had a growth temperature optimum of 43°C. A comparison of strain PPAV 16s rRNA sequences with those of other Mollicutes revealed a high degree of sequence similarity to a strain of Mycoplasma iowae, which is commonly encountered in poultry. This relationship was confirmed by performing a restriction endonuclease pattern analysis and DNA-DNA hybridization tests. The genome size of type strain 695 of M. iowae was determined to be about 1,000 MDa (1,500 kbp) by renatzlration kinetics, a value which is much higher than any other value known in the genus. Additional measurements by pulsed-field gel electrophoresis yielded values of 1,300 kbp for both strain PPAV and M. iowae. Subsequent phenotypic comparisons supported this relationship. Serologic tests with strain PPAV and other strains of M. iowae confirmed the findings of other investigators that this species is serologically heterogeneous. The high optimum temperature for growth of strain PPAV was also shared by a number of M. iowae isolates. Genome size is an inappropriate character for taxonomic assignrhent to the family Mycoplasmataceae because strain PPAV an
-
spiroplasma citri a plant pathogenic mollicute relationships with its two hosts the plant and the leafhopper vector
Annual Review of Phytopathology, 2003Co-Authors: Joseph M. Bové, Colette Saillard, Joël Renaudin, Xavier Foissac, Monique GarnierAbstract:▪ Abstract Spiroplasma citri, the type species of the genus Spiroplasma (Spiroplasmataceae, Mollicutes), is restricted to the phloem sieve tubes and transmitted by phloem sap-feeding insects, as is characteristic of the phytopathogenic Mollicutes. The spiroplasmas are the only Mollicutes showing motility and helical morphology, apparently mediated by a contractile fibrillar cytoskeleton bound to the inner surface of the spiroplasmal membrane. MreB genes, which are involved in cell-shape determination, have been identified in S. citri. Identified genes of other functional groups are those involved in the transmission of S. citri by the leafhoppers and genes coding for lipoproteins, including spiralin, bound to the outer surface of the spiroplasma membrane. S. citri mutants that are unable to use fructose induce only mild and delayed symptoms. Fructose utilization by the sieve tube-restricted wild-type spiroplasmas is postulated to deprive the companion cells of fructose, thereby impairing sucrose loading i...
-
Effect of Polyclonal, Monoclonal, and Recombinant (Single-Chain Variable Fragment) Antibodies on In Vitro Morphology, Growth, and Metabolism of the Phytopathogenic Mollicute Spiroplasma citri
Applied and Environmental Microbiology, 2002Co-Authors: Sylvie Malembic, Colette Saillard, Joseph M. Bové, Monique GarnierAbstract:Antibodies are known to affect the morphology, growth, and metabolism of Mollicutes and thus may serve as candidate molecules for a plantibody-based control strategy for plant-pathogenic spiroplasmas and phytoplasmas. Recombinant single-chain variable fragment (scFv) antibodies are easy to engineer and express in plants, but their inhibitory effects on Mollicutes have never been evaluated and compared with those of polyclonal and monoclonal antibodies. We describe the morphology, growth, and glucose metabolism of Spiroplasma citri in the presence of polyclonal, monoclonal, and recombinant antibodies directed against the immunodominant membrane protein spiralin. We showed that the scFv antibodies had no effect on S. citri glucose metabolism but were as efficient as polyclonal antibodies in inhibiting S. citri growth in liquid medium. Inhibition of motility was also observed.
-
Effect of Polyclonal, Monoclonal, and Recombinant (Single-Chain Variable Fragment) Antibodies on In Vitro Morphology, Growth, and
2001Co-Authors: Metabolism Phytopathogenic, Colette Saillard, Sylvie Malembic, Joseph M. Bové, Mollicute Spiroplasma, Monique GarnierAbstract:Antibodies are known to affect the morphology, growth, and metabolism of Mollicutes and thus may serve as candidate molecules for a plantibody-based control strategy for plant-pathogenic spiroplasmas and phyto-plasmas. Recombinant single-chain variable fragment (scFv) antibodies are easy to engineer and express in plants, but their inhibitory effects on Mollicutes have never been evaluated and compared with those of polyclonal and monoclonal antibodies. We describe the morphology, growth, and glucose metabolism of Spiroplasma citri in the presence of polyclonal, monoclonal, and recombinant antibodies directed against the immunodominant membrane protein spiralin. We showed that the scFv antibodies had no effect on S. citri glucose metabolism but were as efficient as polyclonal antibodies in inhibiting S. citri growth in liquid medium. Inhibition of motility was also observed. Plant-pathogenic Mollicutes include the genus Spiroplasma, comprising organisms culturable in complex artificial media and showing a helical morphology, and the Candidatus genus phytoplasma, containing large numbers of pleiomorphic organ-isms which, until now, have resisted in vitro cultivation (4, 9). Hence, spiroplasmas are the most-studied phytopathogenic Mollicutes, and S. citri (23) is the model organism for this important group of plant pathogens. Mollicutes are eubacteria without a cell wall and thus de-limited only by a cytoplasmic membrane. This characteristic has been linked with the fact that metabolism and growth of Mollicutes were strongly inhibited by antibodies directe
-
Revised taxonomy of the class Mollicutes: proposed elevation of a monophyletic cluster of arthropod-associated Mollicutes to ordinal rank (Entomoplasmatales ord. nov.), with provision for familial rank to separate species with nonhelical morphology (Entomoplasmataceae fam. nov.) from helical species (Spiroplasmataceae), and emended descriptions of the order Mycoplasmatales, family Mycoplasmataceae.
International Journal of Systematic and Evolutionary Microbiology, 1993Co-Authors: Joseph G. Tully, Joseph M. Bové, Frédéric Laigret, Robert F. WhitcombAbstract:On the basis of recent phylogenetic studies of 47 species within the class Mollicutes and recent molecular and physiologic findings that distinguish a new group of non-sterol-requiring insect and plant Mollicutes from Acholeplasma species, we propose a revised taxonomy of the class Mollicutes. Order I (Mycoplasmatales) is retained as described earlier (S. Razin and E. A. Freundt, p. 740-742, in N. R. Krieg and J. G. Holt, ed., Bergey's Manual of Systematic Bacteriology, vol. 1, 1984), with provision for a single family (Mycoplasmataceae) and two genera (Mycoplasma and Ureaplasma) for classification of sterol-requiring Mollicutes primarily associated with vertebrates. Emended descriptions of the order and family for the above taxa are hereby included. Proposed order II (Entomoplasmatales ord. nov.) contains subtaxa for either nonhelical (Entomoplasmataceae fam. nov.) or helical (Spiroplasmataceae) Mollicutes; the latter family is hereby transferred from the order Mycoplasmatales. The new order and family permit designation and classification of a monophyletic cluster of mollicute strains associated primarily with arthropods. It is proposed that nonhelical, sterolrequiring insect and plant Mollicutes previously designated Mycoplasma ellychniae (Tully et al., 1989), Mycoplasma melaleucae (Tully et al., 1990), Mycoplasma somnilux (Williamson et al., 1990), Mycoplasma luminosum (Williamson et al., 1990), and Mycoplasma lucivorax (Williamson et al., 1990) be transferred to Entomoplasma gen. nov., family Entomoplasmataceae fam. nov., as Entomoplasma ellychniae comb. nov., Entomoplasma melaleucae comb. nov., Entomoplasma somnilux comb. nov, Entomoplasma luminosum comb. nov., and Entomoplasma lucivorax comb. nov. Furthermore, the genus Mesoplasma gen. nov. within the family Entomoplasmataceae fam. nov. is proposed for four non-sterol-requiring insect and plant Mollicutes. This designation requires the transfer of Acholeplasma florum (McCoy et al., 1984), Acholeplasma entomophilum (Tully et al., 1988), Acholeplasma seiffertii (Bonnet et al., 1991), and Mycoplasma lactucae (Rose et al., 1990) to Mesoplasma florum comb. nov., Mesoplasma entomophilum comb. nov., Mesoplasma seiffertii comb. nov., and Mesoplasma lactucae comb. nov., respectively. Previously established orders Acholeplasmatales and Anaeroplasmatales within the class Mollicutes are designated orders III and IV, respectively, in the proposed revision. Classification and characteristics of lower taxa within these two orders remain as previously given. The proposal outlined here does not consider the large cluster of nonculturable, arthropod-associated, plant-pathogenic Mollicutes (“mycoplasma-like organisms”) recently shown to be more closely related to members of the order Acholeplasmatales.
Rinaldo A. Mota - One of the best experts on this subject based on the ideXlab platform.
-
Ocorrência de Mollicutes e Ureaplasma spp. em surto de doença reprodutiva em rebanho bovino no Estado da Paraíba Occurrence of Mollicutes and Ureaplasma spp. in outbreak of reproductive disease in cattle herds, State of Paraíba, Brazil
Colégio Brasileiro de Patologia Animal (CBPA), 2013Co-Authors: Sandra Dos B. Santos, Júnior Mário Baltazar De Oliveira, José Pinheiro W. Júnior, Andréa A.f. Oliveira, André Da R. Mota, Guilherme A. Veras, Elmiro Do R. Nascimento, Rinaldo A. MotaAbstract:Em março de 2012 foi diagnosticado um surto de doença reprodutiva em rebanho bovino no Estado da Paraíba, Brasil. Foram examinadas 32 vacas e dois touros da raça Girolando. As vacas apresentaram sinais de doença reprodutiva como repetição de cio, vulvovaginite granular, infertilidade e abortos. As amostras de suabes vaginais e prepuciais foram colhidas e submetidas a isolamento bacteriano e PCR. As reações da PCR para Mollicutes e Ureaplasma spp. foram realizadas com os iniciadores MGSO-GPO3 e UGP'F-UGP'R, respectivamente. Na Nested PCR para Ureaplasma diversum, os iniciadores usados foram UD1, UD2, UD3 e UD4. Para isolamento bacteriano, as amostras foram diluídas de 10-1 até 10-5, semeadas em meio "UB", líquido e placa, sendo incubadas por até 21 dias a 37ºC em jarra de microaerofilia. A frequência de Mollicutes detectada na PCR foi de 65,6% e para Ureaplasma spp. foi de 50,0%, enquanto que para U. diversum foi de 15,6%. No isolamento a frequência de Mollicutes foi de 57,1% e para Ureaplasma spp. foi de 28,6%. No ágar "UB" foi visualizado o crescimento misto de Mycoplasma spp. e Ureaplasma spp. em seis amostras. Foi confirmado o envolvimento de micro-organismos da Classe Mollicutes em surto de doença reprodutiva em vacas no sertão paraibano.In March of 2012 was investigated a reproductive disease outbreak in cattle herds from Paraíba State, Brazil. Were examined 32 cows and two bulls Giroland breed. The cows showed signs and symptoms of reproductive failure such as repeat breeding, granular vulvovaginitis, infertility and abortions. Vaginal and preputial mucous samples were collected for analysis by PCR and isolation. The PCR reactions for Mollicutes and Ureaplasma spp. were realized with primers MGSO and GPO3, and UGP'F and UGP'R respectively. The nested PCR assay for Ureaplasma diversum was realized with primers UD1, UD2, UD3 and UD4. For bacteriologic isolation, obtained samples were diluted up to 10-1 at 10-5, inoculated into liquid and solid "UB" medium, and incubated for up to 21 days, at 37ºC in microaerophilie jar. In the PCR reactions the frequency of Mollicutes detected in the analyzed vaginal mucous samples was 65.6, for Ureaplasma spp. was 50.0, while for U. diversum was 15.6. The frequency for isolation of Mollicutes was of 57.1 and for Ureaplasma spp. was of 28.6. In the UB agar was visualized growth of Mycoplasma spp. and Ureaplasma spp., associated in six of the samples. In the cows the presence of Mollicutes and Ureaplasma spp. was confirmed for the reproductive disease outbreak in the semiarid region of Paraiba
-
Ocorrência de Mollicutes e Ureaplasma spp. em surto de doença reprodutiva em rebanho bovino no Estado da Paraíba
Colégio Brasileiro de Patologia Animal (CBPA), 2013Co-Authors: Sandra Dos B. Santos, Júnior Mário Baltazar De Oliveira, José Pinheiro W. Júnior, Andréa A.f. Oliveira, André Da R. Mota, Guilherme A. Veras, Elmiro Do R. Nascimento, Rinaldo A. MotaAbstract:Em março de 2012 foi diagnosticado um surto de doença reprodutiva em rebanho bovino no Estado da Paraíba, Brasil. Foram examinadas 32 vacas e dois touros da raça Girolando. As vacas apresentaram sinais de doença reprodutiva como repetição de cio, vulvovaginite granular, infertilidade e abortos. As amostras de suabes vaginais e prepuciais foram colhidas e submetidas a isolamento bacteriano e PCR. As reações da PCR para Mollicutes e Ureaplasma spp. foram realizadas com os iniciadores MGSO-GPO3 e UGP'F-UGP'R, respectivamente. Na Nested PCR para Ureaplasma diversum, os iniciadores usados foram UD1, UD2, UD3 e UD4. Para isolamento bacteriano, as amostras foram diluídas de 10-1 até 10-5, semeadas em meio "UB", líquido e placa, sendo incubadas por até 21 dias a 37ºC em jarra de microaerofilia. A frequência de Mollicutes detectada na PCR foi de 65,6% e para Ureaplasma spp. foi de 50,0%, enquanto que para U. diversum foi de 15,6%. No isolamento a frequência de Mollicutes foi de 57,1% e para Ureaplasma spp. foi de 28,6%. No ágar "UB" foi visualizado o crescimento misto de Mycoplasma spp. e Ureaplasma spp. em seis amostras. Foi confirmado o envolvimento de micro-organismos da Classe Mollicutes em surto de doença reprodutiva em vacas no sertão paraibano
Robert F. Whitcomb - One of the best experts on this subject based on the ideXlab platform.
-
the genus spiroplasma and its non helical descendants phylogenetic classification correlation with phenotype and roots of the mycoplasma mycoides clade
International Journal of Systematic and Evolutionary Microbiology, 2004Co-Authors: Gail E. Gasparich, Frank E. French, Robert F. Whitcomb, Deborah Dodge, John Glass, David L. WilliamsonAbstract:The genus Spiroplasma (helical Mollicutes: Bacteria: Firmicutes: Mollicutes: Entomoplasmatales: Spiroplasmataceae) is associated primarily with insects. The Mycoplasma mycoides cluster (sensu Weisburg et al. 1989 and Johansson and Pettersson 2002 ) is a group of Mollicutes that includes the type species – Mycoplasma mycoides – of Mycoplasmatales, Mycoplasmataceae and Mycoplasma. This cluster, associated solely with ruminants, contains five other species and subspecies. Earlier phylogenetic reconstructions based on partial 16S rDNA sequences and a limited sample of Spiroplasma and Mycoplasma sequences suggested that the genus Mycoplasma was polyphyletic, as the M. mycoides cluster and the grouping that consisted of the hominis and pneumoniae groups of Mycoplasma species were widely separated phylogenetically and the M. mycoides cluster was allied with Spiroplasma. It is shown here that the M. mycoides cluster arose from Spiroplasma through an intermediate group of non-helical spiroplasmal descendants – the Entomoplasmataceae. As this conclusion has profound implications in the taxonomy of Mollicutes, a detailed phylogenetic study of Spiroplasma and its non-helical descendants was undertaken. These analyses, done with maximum-parsimony, provide cladistic status; a new nomenclature is introduced here, based on ‘bottom-up’ rather than ‘top-down’ clade classification. The order Entomoplasmatales consists of four major clades: (i) the Mycoides–Entomoplasmataceae clade, which contains M. mycoides and its allies and Entomoplasma and Mesoplasma species and is a sister lineage to (ii) the Apis clade of Spiroplasma. Spiroplasma and the Entomoplasmataceae are paraphyletic, but this status does not diminish their phylogenetic usefulness. Five species that were previously unclassified phylogenetically are basal to the Apis clade sensu strictu and to the Mycoides clade. One of these species, Spiroplasma sp. TIUS-1, has very poor helicity and a very small genome (840 kbp); this putative species can be envisioned as a ‘missing link’ in the evolution of the Mycoides–Entomoplasmataceae clade. The other two Spiroplasma clades are: (iii) the Citri–Chrysopicola–Mirum clade (serogroups I, II, V and VIII) and (iv) the ixodetis clade (serogroup VI). As Mesoplasma lactucae represents a basal divergence within the Mycoides–Entomoplasmataceae clade, and as Entomoplasma freundtii is basal to the Mycoides clade, M. mycoides and its allies must have arisen from an ancestor in the Entomoplasmataceae. The paraphyletic grouping that consists of the Hominis and Pneumoniae groups (sensu Johansson & Pettersson 2002 ) of Mycoplasma species contains the ancestral roots of Ureaplasma spp. and haemoplasmas. This clade is a sister lineage to the Entomoplasmatales clade. Serological classifications of spiroplasma are very highly supported by the trees presented. Genome size and G+C content of micro-organismal DNA were moderately conserved, but there have been frequent and polyphyletically distributed genome reductions. Sterol requirements were polyphyletic, as was the ability to grow in the presence of polyoxyethylene sorbitan-supplemented, but not serum-supplemented, media. As this character is not phylogenetically distributed, Mesoplasma and Entomoplasma should be combined into a single genus. The phylogenetic trees presented here confirm previous reports of polyphyly of the genus Mycoplasma. As both clades of Mycoplasma contain several species of great practical importance, a change of the genus name for species in either clade would have immense practical implications. In addition, a change of the genus name for M. mycoides would have to be approved by the Judicial Commission. For these reasons, the Linnaean and phylogenetic classifications of Mycoplasma must for now be discrepant.
-
Revised taxonomy of the class Mollicutes: proposed elevation of a monophyletic cluster of arthropod-associated Mollicutes to ordinal rank (Entomoplasmatales ord. nov.), with provision for familial rank to separate species with nonhelical morphology (Entomoplasmataceae fam. nov.) from helical species (Spiroplasmataceae), and emended descriptions of the order Mycoplasmatales, family Mycoplasmataceae.
International Journal of Systematic and Evolutionary Microbiology, 1993Co-Authors: Joseph G. Tully, Joseph M. Bové, Frédéric Laigret, Robert F. WhitcombAbstract:On the basis of recent phylogenetic studies of 47 species within the class Mollicutes and recent molecular and physiologic findings that distinguish a new group of non-sterol-requiring insect and plant Mollicutes from Acholeplasma species, we propose a revised taxonomy of the class Mollicutes. Order I (Mycoplasmatales) is retained as described earlier (S. Razin and E. A. Freundt, p. 740-742, in N. R. Krieg and J. G. Holt, ed., Bergey's Manual of Systematic Bacteriology, vol. 1, 1984), with provision for a single family (Mycoplasmataceae) and two genera (Mycoplasma and Ureaplasma) for classification of sterol-requiring Mollicutes primarily associated with vertebrates. Emended descriptions of the order and family for the above taxa are hereby included. Proposed order II (Entomoplasmatales ord. nov.) contains subtaxa for either nonhelical (Entomoplasmataceae fam. nov.) or helical (Spiroplasmataceae) Mollicutes; the latter family is hereby transferred from the order Mycoplasmatales. The new order and family permit designation and classification of a monophyletic cluster of mollicute strains associated primarily with arthropods. It is proposed that nonhelical, sterolrequiring insect and plant Mollicutes previously designated Mycoplasma ellychniae (Tully et al., 1989), Mycoplasma melaleucae (Tully et al., 1990), Mycoplasma somnilux (Williamson et al., 1990), Mycoplasma luminosum (Williamson et al., 1990), and Mycoplasma lucivorax (Williamson et al., 1990) be transferred to Entomoplasma gen. nov., family Entomoplasmataceae fam. nov., as Entomoplasma ellychniae comb. nov., Entomoplasma melaleucae comb. nov., Entomoplasma somnilux comb. nov, Entomoplasma luminosum comb. nov., and Entomoplasma lucivorax comb. nov. Furthermore, the genus Mesoplasma gen. nov. within the family Entomoplasmataceae fam. nov. is proposed for four non-sterol-requiring insect and plant Mollicutes. This designation requires the transfer of Acholeplasma florum (McCoy et al., 1984), Acholeplasma entomophilum (Tully et al., 1988), Acholeplasma seiffertii (Bonnet et al., 1991), and Mycoplasma lactucae (Rose et al., 1990) to Mesoplasma florum comb. nov., Mesoplasma entomophilum comb. nov., Mesoplasma seiffertii comb. nov., and Mesoplasma lactucae comb. nov., respectively. Previously established orders Acholeplasmatales and Anaeroplasmatales within the class Mollicutes are designated orders III and IV, respectively, in the proposed revision. Classification and characteristics of lower taxa within these two orders remain as previously given. The proposal outlined here does not consider the large cluster of nonculturable, arthropod-associated, plant-pathogenic Mollicutes (“mycoplasma-like organisms”) recently shown to be more closely related to members of the order Acholeplasmatales.
