jeanflop/post_ocr_correction2 huggingface dataset:
chromosome. Il est intéressant de noter que la région qui est plus courte chez S. melliferum correspond à une région variable en taille chez différentes souches de S. citri. D'autre part, aucun des gènes conservés que nous avons étudiés ne se positionne autour de la région où la replication se termine (positions 140 à 210 et 170 à 250 chez S. citri et S. melliferum, respectivement). Cette région pourrait être spécifique de l'espèce. REFERENCES 1. Tully J. G., Bové J. M., Laigret F., Whitcomb R. F. 1993. 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 non-helical morphology (Entomoplasmataceae, fam. nov.) from helical species (Spiroplasmataceae), and emended descriptions of the order Mycoplasmatales, family Mycoplasmataceae. Int. J. Syst. Bacteriol. 43: 378-85. 2. Williamson D. L, Tully J. G., Whitcomb R. F. 1989. The genus Spiroplasma. In: Whitcomb R. F., Tully J. G., eds. The Mycoplasmas, vol. V., New York: Academic press, 71-111. 3. Saglio P., Lhospital M., Laflèche D., Dupont G., Bové J. M., Tully J. G., Freundt E. A. 1973. Spiroplasma citri gen. and sp. n.: a mycoplasma-like organism associated with "stubborn" disease of citrus. Int. J. Syst. Bacteriol. 23: 191-204. 4. Bové J. M., Carle P., Garnier M., Laigret F., Renaudin J., Saillard C. 1989. Molecular and cellular biology of spiroplasmas. In: Whitcomb R. F., Tully J. G., eds. The Mycoplasmas, vol. V., New York: Academic Press, 244-364. Clark T. B., 1977. Spiroplasma sp., a new pathogen in honeybees. J. Invertebr. Pathol. 29: 112-3. Wollman E. L., Jacob F. 1959. La sexualité des bactéries. Paris: Masson. Pyle L. E., Corcoran L. N., Cocks B. J., Bergemann A. D., Whitley J. C., Finch L. R. 1988. Pulsed-field electrophoresis indicates larger than expected sizes for mycoplasma genomes. Nucleic Acids Res. 16: 6015-25. Neimark H. C., Lange C. S. 1990. Pulse-field electrophoresis indicates full-length mycoplasma chromosomes range widely in size. Nucleic Acids Res. 18: 5443-8. Grau O., Laigret F., Carie P., Tully J. G., Rose D. L., Bové J. M. 1991.
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1992. Physical and genetic mapping of the genomes of five Mycoplasma hominis strains by pulsed-field gel electrophoresis. J. Bacteriol. 174: 2199-207. 19. Ye F., Laigret F., Whitley J. C., Citti C., Finch L. R., Carie P., Renaudin J., Bové J. M. 1992. A physical and genetic map of the Spiroplasma citri genome. Nucleic Acids Res. 20: 1559-65. 20. Clark T. B., Whitcomb R. F., Tully J. G., Mouches C., Saillard C., Bové J. M., Wroblewski H., Carie P., Rose D. L., Henegar R. B., Williamson D. L. 1985. Spiroplasma melliferum, a new species from the honeybee (Apis mellifera). Int. J. Syst. Bacteriol. 35: 296-308. 21. Whitcomb R. F. 1983. Culture media for spiroplasmas. In: Razin S., Tully J. G. eds. Methods in mycoplasmology. New York: Academic Press, 147-59. 22. Southern E. M. 1975. Detection of specific sequences among DNA fragments separated by gel electrophoresis. J. Mol. Biol. 98: 503-17. 23. Reed K. C., Mann D. A. 1985. Rapid transfer of DNA from agarose gels to nylon membranes. Nucleic Acids Res. 13: 7207-21. 24. Chevalier C., Saillard C., Bové J. M. 1990. Organization and nucleotide sequences of the Spiroplasma citri genes for ribosomal protein S2, elongation factor Ts, spiralin, phosphofructokinase, pyruvate kinase, and an unidentified protein. J. Bacteriol. 172: 2693-703. 25. Williamson D. L., Renaudin J., Bové J. M. 1991. Nucleotide sequence of the Spiroplasma citri fibrillar protein gene. J. Bacteriol. 176: 4353-62. 26. Inamine J. M., Loechel S., Hu P. C. 1989. Nucleotide sequence of the tuf gene from Mycoplasma gallisepticum. Nucleic Acids Res. 17: 10126. 27. Citti, C. 1992. Contribution à l'étude de l'organisation du génome Spiroplasma citri. Ph.D. thesis. University of Bordeaux II, Bordeaux, France. 28. Ye F. 1993. Étude de l'organisation génétique des spiroplasmes. Ph.D. thesis. University of Bordeaux II, Bordeaux, France. 29. Ye F., Renaudin J., Bové J. M., Laigret F. 1993. Cloning and sequencing of the replication origin (oriC) of the Spiroplasma citri chromosome and construction of autonomously replicating artificial plasmids. Curr. Microbiol. (in press). 30. Laigret F., Grau O., Bové J. M. 1990. Comparison of 16S rDNA sequences of various mollicutes. In: Stanek G.,
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tryptophanyl-tRNAs and organization of the corresponding genes. J. Bacteriol. 174: 6471-8. 32. Samuelsson T., Guindy Y. 1990. Nucleotide sequence of a Mycoplasma mycoides RNA which is homologous to E. coli 4.5S RNA. Nucleic Acids Res. 18: 4938. 33. Renaudin J., Aullo P., Vignault J. C., Bové J. M. 1990. Complete nucleotide sequence of the genome of Spiroplasma citri virus SpV1 -R8A2 B. Nucleic Acids Res. 18: 1293. 34. Renaudin J., Bodin-Ramiro C., Vignault J. C., Bové J. M. 1990. Spiroplasmavirus 1: presence of viral DNA sequences in the Spiroplasma genome. In: Stanek G., Cassell G. H., Tully J. G., Whitcomb R. F. eds. Recent advances in Mycoplasmology, Zbl. Bakt. suppl. 20, Stuttgart, New York: Gustav Fisher Verlag, 125-30. 35. Chevalier C., Saillard C., Bové J. M. 1990. Spiralins of Spiroplasma citri and Spiroplasma melliferum: amino acid sequences and putative organization in the cell membrane. J. Bacteriol. 172: 6090-7. 36. Christiansen C., Erno H. 1982. Classification of the F38 group of caprine Mycoplasma strains by DNA hybridization. J. Gen. Microbiol. 128: 25236. 37. Weisburg W. G., Tully J. G., Rose D. L., Petzel J. P., Oyaizu H., Yang D., Mandelco L., Sechrest J., Lawrence T. G., Van Etten J., Maniloff J., Woese C. R. 1989. A phylogenetic analysis of the Mycoplasmas: basis for their classification. J Bacteriol. 171: 6455-67. 398 C. R. Acad. Sci. Paris, Sciences de la vie/Life sciences, 1994; 317: 392-8 C. R. Acad. Sci. Paris, Sciences de la vie/Life sciences, 1994; 317: 399-404 Biologie et génétique moléculaire/Molecular biology and genetics ABSTRACT Pulsed field gel electrophoresis (PFGE) was used to separate chromosome-sized DNA from two species of microsporidia of fishes. The molecular karyotype of Glugea atherinae exhibits 16 DNA bands from 420 to 2,700 kb, and that of Spraguea lophii 12 bands from 230 to 980 kb. Until now they represent respectively the largest and the smallest genomes visualized for microsporidia: 19.5 Mb for G. atherinae and 6.2 Mb for S. lophii (the smallest nuclear genome in eukaryotic organism). We have analysed separately five strains of G. atherinae (individual cysts), with this technique. The electrophoretic spectra are the same
Woese C. R. 1989. A phylogenetic analysis of the Mycoplasmas: basis for their classification. J Bacteriol. 171: 6455-67. 398 C. R. Acad. Sci. Paris, Sciences de la vie/Life sciences, 1994; 317: 392-8 C. R. Acad. Sci. Paris, Sciences de la vie/Life sciences, 1994; 317: 399-404 Biologie et génétique moléculaire/Molecular biology and genetics ABSTRACT Pulsed field gel electrophoresis (PFGE) was used to separate chromosome-sized DNA from two species of microsporidia of fishes. The molecular karyotype of Glugea atherinae exhibits 16 DNA bands from 420 to 2,700 kb, and that of Spraguea lophii 12 bands from 230 to 980 kb. Until now they represent respectively the largest and the smallest genomes visualized for microsporidia: 19.5 Mb for G. atherinae and 6.2 Mb for S. lophii (the smallest nuclear genome in eukaryotic organism). We have analysed separately five strains of G. atherinae (individual cysts), with this technique. The electrophoretic spectra are the same for these strains, except for the absence of the 2,380-kb band in one case. Therefore, the karyotype seems to be rather well conserved for this species. ▲ Key words: Protozoa, Microsporidia, Glugea atherinae, Spraguea lophii, pulsed field gel electrophoresis, molecular karyotype, genome size. RÉSUMÉ Une technique d'électrophorèse en champ pulsé (PFGE) a été utilisée pour séparer l'ADN de taille chromosomique chez deux Microsporidies parasites de poissons. Le caryotype moléculaire de Glugea atherinae présente 16 bandes d'ADN, de 420 à 2700 kb, et celui de Spraguea lophii, 12 bandes de 230 à 980 kb. Ils représentent, respectivement, le plus grand et le plus petit génome visualisé pour les microsporidies: 19,5 Mb pour G. atherinae et 6,2 Mb pour S. lophii (le plus petit génome nucléaire actuellement connu pour un Eucaryote). Nous avons étudié séparément, grâce à cette technique, 5 kystes de G. atherinae. Les spectres électrophorétiques sont identiques pour ces souches, excepté l'absence de la bande de 2380 kb chez une souche. Le caryotype semble donc plutôt conservé pour cette espèce. A Mots clés: Protozoaire, Microsporidies, Glugea atherinae, Spraguea lophii, électrophorèse en champ pulsé, caryotype moléculaire, taille génomique. Voir Version abrégée (p. 402) Note présentée par Constantin Vago. Note remise le
(PFGE) a été utilisée pour séparer l'ADN de taille chromosomique chez deux Microsporidies parasites de poissons. Le caryotype moléculaire de Glugea atherinae présente 16 bandes d'ADN, de 420 à 2700 kb, et celui de Spraguea lophii, 12 bandes de 230 à 980 kb. Ils représentent, respectivement, le plus grand et le plus petit génome visualisé pour les microsporidies: 19,5 Mb pour G. atherinae et 6,2 Mb pour S. lophii (le plus petit génome nucléaire actuellement connu pour un Eucaryote). Nous avons étudié séparément, grâce à cette technique, 5 kystes de G. atherinae. Les spectres électrophorétiques sont identiques pour ces souches, excepté l'absence de la bande de 2380 kb chez une souche. Le caryotype semble donc plutôt conservé pour cette espèce. A Mots clés: Protozoaire, Microsporidies, Glugea atherinae, Spraguea lophii, électrophorèse en champ pulsé, caryotype moléculaire, taille génomique. Voir Version abrégée (p. 402) Note présentée par Constantin Vago. Note remise le 28 mars 1994, acceptée le 6 avril 1994. 399 C. Biderre et al. Microsporidia, phylum Microspora [1], are obligate intracellular parasitic Protozoa with a wide host distribution covering most invertebrate phyla and all five classes of vertebrates, including man [2]. The transmission between hosts occurs through résistant spores that possess a proteinaceous exospore and an endospore composed of chitin and protein. In response to stimuli at the site of germination [9], they eject a long tubular structure ("polar filament") through which the infectious sporoplasm flows into the cytoplasm of the host cell. The sporoplasm, consisting of nucleus and some cytoplasm, divides rapidly within the host cytoplasm. These small-sized eukaryotes are unusual because they lack mitochondria [3] and having 70S prokaryote-type ribosomes [4, 5]. Comparison of ribosomal (16S and 23S) RNA séquences with other eukaryotes suggests that these microorganisms diverged early during evolution [6, 7, 8]. The studies on the genomic organization of the microsporidia are poorly developed. Because of their small size and obligate intracellular feature, we developed procedures that induce in vitro germination, in order to apply the pulsed-field gel electrophoresis (PFGE) [10]. This technique has been successfully used for the resolution of chromosomal DNAs from numerous prokaryotic and
a proteinaceous exospore and an endospore composed of chitin and protein. In response to stimuli at the site of germination [9], they eject a long tubular structure ("polar filament") through which the infectious sporoplasm flows into the cytoplasm of the host cell. The sporoplasm, consisting of nucleus and some cytoplasm, divides rapidly within the host cytoplasm. These small-sized eukaryotes are unusual because they lack mitochondria [3] and having 70S prokaryote-type ribosomes [4, 5]. Comparison of ribosomal (16S and 23S) RNA séquences with other eukaryotes suggests that these microorganisms diverged early during evolution [6, 7, 8]. The studies on the genomic organization of the microsporidia are poorly developed. Because of their small size and obligate intracellular feature, we developed procedures that induce in vitro germination, in order to apply the pulsed-field gel electrophoresis (PFGE) [10]. This technique has been successfully used for the resolution of chromosomal DNAs from numerous prokaryotic and eukaryotic organisms. Munderloh et al. [11] have visualized the molecular karyotypes of the microsporidia Nosema pyrausta and Nosema furnacalis. In the same way, Malone and McIvor [12] have studied four microsporidian isolates: two isolates of Vavraia oncoperae (one from grass grubs Costelytra zealandica and the other from porina caterpillars Wiseana sp.), one isolate of Nosema costelytrae and an other isolate of Vairimorpha sp. from Pieris rapae (Table II). We studied two microsporidian species, Glugea atherinae and Spraguea lophii, parasites of fishes. At the initial infection site, the development of the parasite causes the formation of a cyst containing a great number of spores. For the two species, we have extracted the intact DNA in order to resolve the molecular karyotypes by contour-clamped homogeneous electric field (CHEF) electrophoresis [13] and to detect a possible polymorphism. Table I Size (kb) and number of chromosomal DNA bands from Spraguea lophii and Glugea atherinae, parasites of fishes, and from strain 288C of Saccharomyces cerevisiae (size standards) band Saccharomyces Spraguea Glugea No. cerevisiae lophii atherinae 1 2,600 980 2,700 2 1,700 920, 2,380 3 1,180 750 2,180 4 920 700 1,700 5 870 540 1,540 6 820 480 1,280 7 700 400 1,140 8 600
sp.), one isolate of Nosema costelytrae and an other isolate of Vairimorpha sp. from Pieris rapae (Table II). We studied two microsporidian species, Glugea atherinae and Spraguea lophii, parasites of fishes. At the initial infection site, the development of the parasite causes the formation of a cyst containing a great number of spores. For the two species, we have extracted the intact DNA in order to resolve the molecular karyotypes by contour-clamped homogeneous electric field (CHEF) electrophoresis [13] and to detect a possible polymorphism. Table I Size (kb) and number of chromosomal DNA bands from Spraguea lophii and Glugea atherinae, parasites of fishes, and from strain 288C of Saccharomyces cerevisiae (size standards) band Saccharomyces Spraguea Glugea No. cerevisiae lophii atherinae 1 2,600 980 2,700 2 1,700 920, 2,380 3 1,180 750 2,180 4 920 700 1,700 5 870 540 1,540 6 820 480 1,280 7 700 400 1,140 8 600 350 1,100 9 450 310 960 10 350 300 940 11 290 260 760 12 250 230 730 13 620 14 540 15 520 16 420 Materials and methods Microsporidian spores Cysts containing spores of Glugea atherinae Berrebi, 1978, were extracted from the generalized cavity of a great number of fishes, Atherina boyeri Risso, 1810, caught in the Languedoc ponds between December 1992 and March 1993. In each fish, we generally found only one cyst up to 10 mm in diameter and containing spores of 5 to 6 μm. Cysts including spores of Spraguea lophii Doflein, 1898, were recovered from neurons of the central nervous Table II Comparison of size (kb) and number of chromosomal DNA bands from 8 microsporidian species species of number of band size genome size references microsporidia bands range (kb) estimate (kb) V. oncoperae* 14 130-1,930 8,000 Malone and V. oncoperae* 16 140-1,830 10,240 McIvor 1993 [12] Vairimorpha sp. 8 720-1,790 9,250 N. costelytrae 8 290-1,810 7,420 N. furnacalis 13 440-1,390 10,240 Munderloh et al. N. pyrausta 13 440-1,360 10,560 1990 [11] S. lophii 12 230-980 6,220 présent study G. atherinae 16 420-2,700 19,510 " * Vavraia oncoperae, (the first from grass grubs and the other
fishes, Atherina boyeri Risso, 1810, caught in the Languedoc ponds between December 1992 and March 1993. In each fish, we generally found only one cyst up to 10 mm in diameter and containing spores of 5 to 6 μm. Cysts including spores of Spraguea lophii Doflein, 1898, were recovered from neurons of the central nervous Table II Comparison of size (kb) and number of chromosomal DNA bands from 8 microsporidian species species of number of band size genome size references microsporidia bands range (kb) estimate (kb) V. oncoperae* 14 130-1,930 8,000 Malone and V. oncoperae* 16 140-1,830 10,240 McIvor 1993 [12] Vairimorpha sp. 8 720-1,790 9,250 N. costelytrae 8 290-1,810 7,420 N. furnacalis 13 440-1,390 10,240 Munderloh et al. N. pyrausta 13 440-1,360 10,560 1990 [11] S. lophii 12 230-980 6,220 présent study G. atherinae 16 420-2,700 19,510 " * Vavraia oncoperae, (the first from grass grubs and the other from porina caterpillars). 400 C. R. Acad. Sci. Paris, Sciences de la vie/Life sciences, 1994; 317: 399-404 On small genomes in eukaryotic organisms System of Lophius piscatorius Linné, 1798, caught on the French Atlantic coast between December 1992 and March 1993. These cysts of small size (often less than 1 mm in diameter) are very numerous and contain two forms of spores: a round peripheral monokaryotic form (3.5 µm) and a reniform central diplokaryotic form (4 µm). Cysts extracted from host tissues were first washed three times by centrifugation at 90 g in phosphate buffer saline (PBS). Then, they were crushed mechanically in a Polytron homogenizer to release the spores. Following several washings in PBS to eliminate the fragments of fish tissues, the spores were purified by centrifugation at 540 g for 30 min through a discontinuous gradient consisting of layers of 25, 50, 75 and 100 % Percoll [15]. They were finally washed in PBS by three centrifugations at 540 g and stored in the same buffer at 4 °C. Spore germination The germination of spores of microsporidia can be induced by several environmental parameters that differ from one species to another. A suspension containing 4.108 spores in PBS