Plasmids in rhizobia: The role of nonsymbiotic plasmids

Molecular Plant-Microbe Interactions

Volumn 9, Issue 7, 1996, Pages 535-545

  Mercado Blanco, Jesús ^a   Toro, Nicolás ^b  

^a UTRECHT UNIVERSITY   (Netherlands)

^b CSIC   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

RHIZOBIACEAE;

EID: 0030444507     PISSN: 08940282     EISSN: None     Source Type: Journal    
DOI: 10.1094/MPMI-9-0535     Document Type: Review

References (140)

1. Baldani, J. I., and Weaver, R. W. 1992. Survival of clover rhizobia and their plasmid-cured derivatives in soil under heat and drought stress. Soil Biol. Biochem. 24.737-742.
2. Baldani, J I., Weaver, R. W., Hynes, M. F., and Eardly, B. D. 1992. Utilization of carbon substrates, electrophoretic enzyme patterns, and symbiotic performance of plasmid-cured clover rhizobia. Appl. Environ. Microbiol. 58:2308-2314.
3. Banfalvi, Z , Kondorosi, E., and Kondorosi, A. 1985. Rhizobium meliloti carries two megaplasmids. Plasmid 13:129-138.
4. Banfalvi, Z., Sakanyan, V., Konez, C., Kiss, A., Dusha, I., and Kondorosi, A. 1981. Location of nodulation and nitrogen fixation genes on a high molecular weight plasmid of Rhizobium meliloti. Mol. Gen. Genet. 184:318-325.
5. Barbour, W. M., and Elkan, G. H. 1989. Relationship of the presence of copy number of plasmids to exopolysaccharide production and symbiotic effectiveness in Rhizobium fredii USDA 206. Appl. Environ. Microbiol. 55:813-818.
6. Barbour, W. M., and Elkan, G. H. 1990. Physiological characteristics and competitive ability of plasmid-cured derivatives of Rhizobium fredii USDA 206. Arch. Microbiol. 154:1-4.
7. Barran, L. R., and Bromfield, E. S. P. 1988. Symbiotic gene probes hybridize to cryptic plasmids of indigenous Rhizobium meliloti. Can. J. Microbiol. 34:703-707.
8. Bernard, T., Pocard, J. A., Perroud, B., and Le Rudulier, D. 1986. Variations in the response of salt-stressed Rhizobium strains to betaines. Arch. Microbiol. 143:359-364.
9. Boivin, C., Malpica, C., Rosenberg, C., Goldman, A., Flevry, V., Maille, M., Message, B., Pamboukdjian, N., and Tepfer, D. 1990. Catabolism of the plant secondary metabolites calystegins and trigonelline by Rhizobium meliloti. Symbiosis 9:147-154.
10. Borthakur, D., Lamb, J. W., and Johnston, A. W. B. 1987 Identification of two classes of Rhizobium phaseoli genes required for melanin synthesis, one of which is required for nitrogen fixation and activates the transcription of the other. Mol. Gen. Genet. 207:155-160.
11. Bramhill, D., and Kornberg, A 1988. Duplex opening by DnaA protein at novel sequences in initiaton of replication at the origin of the E. coli chromosome. Cell 52:743-755.
12. Brom, S., García de los Santos, A., Stepkowsky, T., Flores, M., Dávila, G., Romero, D., and Palacios, R. 1992. Different plasmids of Rhizobium leguminosarum bv. phaseoli are required for optimal symbiotic performance. J Bacteriol. 174:5183-5189.
13. Brom, S., Santos, A. G., Girard, M. L., Dávila, G., Palacios, R., and Romero, D. 1991. High frecuency rearrangements in Rhizobium leguminosarum bv. phaseoli plasmids. J. Bacteriol. 173:1344-1346.
14. Bromfield, E. S. P., Lewis, D. M., and Barran, L. R. 1985. Cryptic plasmid and rifampin resistance in Rhizobium meliloti influencing nodulation competitiveness. J. Bacteriol. 164:410-413.
15. Broughton, W. J., Keycke, N., Meyer, Z. A. H., and Pankhurst, C. E. 1984. Plasmid-linked nif and nod gene in fast-growing rhizobia that nodulate Glycine max, Posphocarpus tetragonolobus, and Vigna unguiculata. Proc. Natl. Acad. Sci. USA 81:3093-3097.
16. Buchanan-Wollaston, A. V., Beringer, J. E , Brewin, N. J., Hirsch, P. R., and Johnston, A. W. B. 1980. Isolation of symbiotically defective mutants in Rhizobium leguminosarum by insertion of the transposon Tn5 into a transmissible plasmid. Mol. Gen. Genet. 178:185-190.
17. Burkhardt, B., and Burkhardt, H.-J. 1984. Visualization and exact molecular weight determination of a Rhizobium meliloti megaplasmid. J. Mol. Biol. 175:213-218.
18. Burkhardt, B., Schillik, D., and Pühler, A. 1987. Physical characterization of Rhizobium meliloti megaplasmids. Plasmid 17:13-25.
19. Cadahía, E., Leyva, A., and Ruíz-Argueso, T. 1986. Indigenous plasmids and cultural characteristics of rhizobia nodulating chickpeas (Cicer arietinum L.). Arch. Microbiol. 146:239-244.
20. Casse, F , Boucher, C., Julliot, J. S., Michel, M., and Denarie, J. 1979. Identification and characterization of large plasmids in Rhizobium meliloti using agarose gel electrophoresis. J. Gen. Microbiol. 113:229-242.
21. Cava, J. R., Elias, P. M., Turowski, D. A., and Noel, K. D. 1989. Rhizobium leguminosarum CFN42 genetic region encoding lipopolysaccharide structures essential for complete nodule development on bean plants. J. Bacteriol. 171:8-15.
22. Charles, T. C., and Finan, T. M. 1991. Analysis of a 1600-kilobase Rhizobium meliloti megaplasmid using defined deletions generated in vivo. Genetics 127:5-20.
23. Charles, T. C., Singh, R. S , and Finan, T. M. 1990. Lactose utilization and enzymes encoded by megaplasmids in Rhizobium meliloti SU47: Implications for population studies. J. Gen. Microbiol. 136:2497-2502.
24. Chen, H., Gartner, E., and Rolfe, B. G. 1993. Involvement of genes on a megaplasmid in the acid-tolerant phenotype of Rhizobium leguminosarum biovar trifolii. Appl Environ. Microbiol. 59:1058-1064.
25. Chun, J.-Y., and Stacey, G. 1994. A Bradyrhizobium japonicum gene essential for nodulation competitiveness is differentially regulated from two promoters. Mol. Plant-Microbe Interact. 7:248-255.
26. Cubo, M. T , Buendía-Clavería, A. M., Beringer, J. E., and Ruíz-Sainz, J. E. 1988. Melanin production of Rhizobium strains. Appl. Environ. Microbiol. 54:1812-1817.
27. DeJong, T. M., Brewin, N. J., and Phillips, D. A. 1981. Effects of plasmid content in Rhizobium leguminosarum on pea nodule activity and plant growth. J. Gen. Microbiol. 124:1-7.
28. Dusha, I., Kovalenko, S., Banfalvi, Z., and Kondorosi, A. 1987. Rhizobium meliloti insertion element ISRm2 and its use for the identification of the fixX gene. J. Bacteriol. 169:1403-1409.
29. Dylan, T., Ielpi, L., Stanfield, S., Kashyap, L., Douglas, C., Yanofsky, M., Nester, E., Helinski, D. R., and Ditta, G. 1986. Rhizobium meliloti genes required for nodule development are related to chromosomal virulence genes in Agrobacterium tumefaciens. Proc. Natl. Acad. Sci. USA 83:4403-4407.
30. Eckhardt, T. 1978. A rapid method for the identification of plasmid deoxyribonucleic acid in bacteria. Plasmid 1:584-588.
31. Finan, T. M., Kunkel, B., de Vos, G. F., and Signer, E. R. 1986. Second symbiotic megaplasmid in Rhizobium meliloti carrying exopolysaccharide and thiamine synthesis genes. J. Bacteriol. 167:66-72.
32. Finan, T. M., Oresnik, I., and Bottacin, A. 1988. Mutants of Rhizobium meliloti defective in succinate metabolism. J. Bacteriol. 170:3396-3403.
33. Flores, M , González, V., Brom, S., Martínez, E., Piñero, D., Romero, D., Dávila, G., and Palacios, R. 1987. Reiterated DNA sequences in Rhizobium and Agrobacterium spp. J. Bacteriol. 169:5782-5788.
34. Forrai, T , Vincze, E., Banfalvi, Z., Kiss, G. B., Randhawa, G. S., and Kondorosi, A. 1983. Localization of symbiotic mutations in Rhizobium meliloti. J. Bacteriol. 153:635-643.
35. Froissard, D., Bromfield, E. S. P., Whitwill, S., and Barran, L. B. 1995. Construction and properties of cloning vectors based on a 7.2 Kb Rhizobium meliloti cryptic plasmid. Plasmid 33:226-231.
36. Gajendiran, N., and Mahadevan, A. 1990. Plasmid-borne catechol dissimilation in Rhizobium sp. FEMS Microbiol. Ecol. 73:125-130.
37. Gallie, D. R., and Kado, C. I. 1987. Agrobacterium tumefaciens pTAR parA promoter region involved in autoregulation, incompatibility and plasmid partitioning. J. Mol. Biol. 193:465-478.
38. Gallie, D. R., Zaitlin, D., Perry, K. L., and Kado, C. I. 1984. Characterization of the replication and stability regions of Agrobacterium tumefaciens plasmid pTAR. J. Bacteriol. 157:739-745.
39. Gerlitz, M., Hrabak, O., and Schwab, H. 1990. Partitioning of broadhost-range plasmid RP4 is a complex system involving site-specific recombination. J. Bacteriol. 172:6194-6203.
40. Glazebrook, J., and Walker, G. C. 1989. A novel exopolysaccharide can function in place of the calcofluor-binding exopolysaccharide in nodulation of alfalfa by Rhizobium meliloti. Cell 56:661-672.
41. Goldman, A., Lecoeur, L., Message, B., Delarue, M., Schoonejans, E., and Tepfer, D. 1994. Symbiotic plasmid genes essential to the catabolism of proline betaine, or stachydrine, are also required for efficient nodulation by Rhizobium meliloti. FEMS Microbiol. Lett. 115:305-312.
42. Gray, K. M., Pearson, J. P., Downie, J. A., Boboye, B. E. A., and Greenberg, E. P. 1996. Cell-to-cell signaling in the symbiotic nitrogen-fixing bacterium: Autoinduction of a stationary phase and rizosphere-expressed genes. J. Bacteriol. 178:372-376.
43. Hahn, M., and Hennecke, H. 1987. Mapping of a Bradyrhizobium japonicum DNA region carrying genes for symbiosis and an asymmetric accumulation of reiterated sequences. Appl. Environ. Microbiol. 53:2247-2252.
44. Harrison, S. P., Jones, D. G., Schünman, P. H. D., Forster, J. W., and Young, J. P. 1988. Variation in Rhizobium leguminosarum biovar trifolii sym plasmids and the association with effectiveness of nitrogen fixation. J. Gen Microbiol. 134:2721-2730.
45. Hartmann, A., and Amarger, N. 1991. Genotypic diversity of an indigenous Rhizobium meliloti field population assessed by plasmid profiles, DNA fingerprinting, and insertion sequence typing. Can. J. Microbiol. 37:600-608.
46. Haugland, R. A., Cantrell, M. A., Beaty, J. S. Hanus, F. J , Rusell, S. A., and Evans, H. J. 1984. Characterization of Rhizobium japonicum hydrogen uptake genes. J. Bacteriol 159:1006-1012.
47. Haugland, R., and Verma, D. P. S. 1981. Interspecific plasmid and genomic DNA sequence homologies and localization of nif genes in effective and ineffective strains of Rhizobium japonicum. J. Mol. Appl. Genet 1:205-217.
48. Hawkins, F. K. L., Kennedy, C., and Johnston, A. W. B. 1991. A Rhizobium leguminosarum gene required for symbiotic nitrogen fixation, melanin synthesis and normal growth on certain growth media. J. Gen. Microbiol. 137:1721-1728.
49. Hawkins, F. K. L., and Johnston, A. W. B. 1988. Transcription of a Rhizobium leguminosarum biovar phaseoli gene needed for melanin synthesis is activated by nifA of Rhizobium and Klebsiella pneumoniae. Mol. Microbiol. 2:331-337.
50. Herrera-Cervera, J. A., Olivares, J., and Sanjuan, J. 1996. Ammonia inhibition of plasmid pRmeGR4a conjugal transfer between Rhizobium meliloti strains. Appl. Environ. Microbiol 62:1145-1150.
51. Hirsch, P. R. 1979. Plasmid determined bacteriocin production by Rhizobium leguminosarum. J. Gen. Microbiol. 113:219-228.
52. Hirsch, P. R., van Montagu, M., Johnston, A. W. B., Brewin, N. J., and Schell, J. 1980. Physical identification of bacteriocinogenic, nodulation, and other plasmids in strains of Rhizobium leguminosarum. J. Gen. Microbiol. 120:403-412.
53. Holloway, P., McCormick, W., Watson, R. J., and Chan, Y-K. 1996. Identification and analysis of the dissimilatory nitrous oxide reduction genes, nosRZDFY, of Rhizobium meliloti. J. Bacteriol. 178:1505-1514.
54. Hombrecher, G., Brewin, N. J., and Johnston, A. W. B. 1981. Linkage of genes for nitrogenase and nodulation ability on plasmids in Rhizobium leguminosarum and R. phaseoli. Mol. Gen. Genet. 182:133-136.
55. Hooykaas, P. J. J., den Dulk-Ras, M., Regensburg-Twink, A. J. G., van Brussel, A. A., and Schilperoort, R. A. 1985. Expression of a Rhizobium phaseoli sym plasmid in R. trifolii and Agrobacterium tumefaciens: incompatibility with a R. trifolii sym plasmid. Plasmid 14:47-52.
56. Hooykaas, P. J. J., Snijdewint, F. G. M., and Schilperoort, R. A. 1982. Identification of the Sym plasmid of Rhizobium leguminosarum strain 1001 and its transfer to an expression in other rhizobia and Agrobacterium tumefaciens. Plasmid 8:73-82.
57. Huguet, T., Rosenberg, C., Casse-Delbart, F., de Lajudie, P., Jouanin, L., Batut, J., Boistard, D. P., Julliot, J. S., and Dénarié, J. 1983. Studies on Rhizobium meliloti plasmids and on their role in the control of nodule formation and nitrogen fixation: The pSym megaplasmid and the other large plasmids. Pages 35-45 in: Molecular Genetics of the Bacteria-Plant Interaction. A. Pühler, ed. Springer, Berlin.
58. Hynes, M. F., and McGregor, N. F. 1990. Two plasmids other than the nodulation plasmid are necessary for formation of nitrogen-fixing nodules by Rhizobium leguminosarum. Mol. Microbiol. 4:567-574.
59. Hynes, M. F., Brucksch, K., and Priefer, U. 1988. Melanin production encoded by a cryptic plasmid in a Rhizobium leguminosarum strain. Arch. Microbiol. 150:326-332.
60. Hynes, M. F., Simon, R., Müller, P., Niehaus, K., Labes, M., and Pühler, A. 1986. The two megaplasmid of Rhizobium meliloti are involved in the effective nodulation of alfalfa. Mol. Gen. Genet. 202:356-362.
61. Johnston, A. W. B , Beynon, J. L., Buchanan-Wollaston, A. V., Setchell, S. M., Hirsch, P. R., and Beringer, J. E. 1978. High frequency transfer of nodulating ability between strains and species of Rhizobium. Nature 276:634-636.
62. Johnston, A. W. B., Hombrecher, G., Brewin, N. J., and Cooper, M. C. 1982. Two transmissible plasmids in Rhizobium leguminosarum strain 300. J. Gen. Microbiol. 128:85-93.
63. Jouanin, L., de Lajudie, P., Bazetoux, S., and Huguet, T. 1981. DNA sequences homology in Rhizobium meliloti plasmids. Mol. Gen. Genet. 182:189-195.
64. Kaluza, K., Hahn M , and Hennecke, H. 1985 Repeated sequences similar to insertion elements clustered around the nif region of the Rhizobium japonicum genome. J. Bacteriol. 162:535-542.
65. Kondorosi, A., Kondorosi, E., Pankhurst, C. E., Broughton, W. J., and Banfalvi, Z. 1982. Mobilization of a Rhizobium meliloti megaplasmid carrying nodulation and nitrogen fixation genes into other rhizobia and Agrobacterium. Mol. Gen. Genet. 188:433-439.
66. Lamb, J. W., Hombrecher, G., and Johnston, A. W. B. 1982. Plasmid determined nodulation and nitrogen fixation abilities in Rhizobium phaseoli. Mol. Gen. Genet. 186:449-452.
67. Leigh, J. A., Signer, E. R., and Walker, G. C. 1985. Exopolysaccharide-deficient mutants of Rhizobium meliloti that form ineffective nodules. Proc Natl. Acad. Sci. USA 82:6231-6235.
68. + Rhizobium leguminosarum strains. Appl. Environ. Microbiol. 53:2539-2543.
69. Le Rudulier, D., and Bernard, T. 1986. Salt tolerance in Rhizobium: A possible role for betaines. FEMS Microbiol. Rev. 39:67-72.
70. Lindstrom, K. 1989. Rhizobium galegae a new species of legume root nodule bacteria. Int. J. Syst. Bacteriol. 39:365-367.
71. Long, S., McCune, S., and Walker, G. C. 1988. Symbiotic loci of Rhizobium meliloti identified by random TnphoA mutagenesis. J. Bacteriol. 170:4257-4265.
72. Margolin, W., and Long, S. R. 1993. Isolation and characterization of a DNA replication origin from the 1,700-kilobase-pair symbiotic megaplasmid pSym-b of Rhizobium meliloti. J. Bacteriol. 175:6553-6561.
73. Martínez, E., Palacios, R., and Sánchez, F. 1987. Nitrogen-fixing nodules induced by Agrobacterium tumefaciens harbouring Rhizobium phaseoli plasmids. J. Bacteriol. 169:2828-2834.
74. Martínez, E., Romero, D., and Palacios, R. 1990 The Rhizobium genome. Crit. Rev. Plant Sci. 9:59-93.
75. Martínez-Romero, E. 1994. Recent developments in Rhizobium taxonomy. Plant Soil 161:11-20.
76. Martínez-Romero, E., and Rosenblueth, M. 1990. Increased bean (Phaseolus vulgaris L.) nodulation competitiveness of genetically modified Rhizobium strains. Appl. Environ. Microbiol. 56:2384-2388.
77. Martínez-Romero, E., Segovia, L., Martins Mercante, F., Franco, A. A., Graham, P., and Pardo, M. A. 1991. Rhizobium tropici, a novel species nodulating Phaseolus vulgaris L beans and Leucaena sp. trees. Int. J. Syst. Bacteriol. 41:417-426.
78. Masterson, R. V., Rusell, P. R , and Atherly, A. G. 1982. Nitrogen fixation (nif) genes and large plasmids of Rhizobium japonicum. J. Bacteriol. 152:928-931.
79. Mercado-Blanco, J., and Olivares, J. 1993. Stability and transmissibility of the cryptic plasmids of Rhizobium meliloti GR4: Their possible use in the construction of cloning vectors for rhizobia. Arch. Microbiol. 160:477-485.
80. Mercado-Blanco, J., and Olivares, J. 1994a. A protein involved in stabilization of a large non-symbiotic plasmid of Rhizobium meliloti shows homology to eukaryotic cytoskeletal proteins and DNA-binding proteins. Gene 139:133-134.
81. Mercado-Blanco, J., and Olivares, J. 1994b. The large non-symbiotic plasmid pRmeGR4a of Rhizobium meliloti GR4 encodes a protein involved in replication that has homology with the RepC protein of Agrobacterium plasmids Plasmid 32:75-79.
82. Mercado-Blanco, J., García, F., Fernández-López, M., and Olivares, J. 1993. Melanin production by Rhizobium meliloti GR4 is linked to nonsymbiotic plasmid pRmeGR4b: Cloning, sequencing, and expression of the tyrosinase gene mepA. J. Bacteriol. 175:5403-5410.
83. Meyer, R., Laux, R., Boch, G., Hinds, M., Bayly, R., and Shapiro, J. A. 1982. Broad-host-range IncP-4 plasmid R1162: Effects of deletions and insertions on plasmid maintenance and host range. J. Bacteriol. 152:140-150.
84. Moënne-Loccoz, Y., and Weaver, R. W. 1995. Plasmids influence growth of rhizobia in the rizhosphere of clover. Soil Biol. Biochem. 27:1001-1004.
85. Motallebi-Veshareh, M., Rouch, D. A., and Thomas, C. M. 1990. A family of ATPases involved in active partitioning of diverse bacterial plasmids. Mol. Microbiol. 4:1445-1463.
86. Mozo, M. T., Cabrera, E., and Ruíz-Argueso, T. 1988. Diversity of plasmid profiles and conservation of symbiotic nitrogen fixation genes in newly isolated Rhizobium strains nodulating Zulla (Hedysarum coronarium L.). Appl. Environ. Microbiol. 54:1262-1267.
87. Mozo, M. T., Cabrera, E., and Ruíz-Argueso, T. 1990. Isolation of the replication region from a Rhizobium plasmid an examination of its potential as a replicon for Rhizobiaceae cloning vectors. Plasmid 23:201-215.
88. Muller, P., Hynes, M. F., Fapp, D., Niehaus, K., and Pühler, A. 1988. Two classes of Rhizobium meliloti infection mutants differ in exopolysaccharide production and coinoculation properties with nodulation mutants. Mol. Gen. Genet. 211:17-26.
89. Murphy, P. J., and Saint, C. P. 1992. Rhizopines in the legume-Rhizobium symbiosis. Pages 377-390 in: Molecular Signals in Plant-Microbe Communications. D. P. S. Verma, ed. CRC Press, Boca Raton, FL.
90. Neilan, J., Heery, D., and Dunican, L. K. 1986. Isolation of replication loci of plasmid origin from Rhizobium trifolii. Biochem. Soc. T. 14:478.
91. Nishiguchi, R., Takanami, M., and Oka, A. 1987. Characterization and sequence determination of the replicator region in the hairy-root-inducing plasmid pRiA4b. Mol. Gen. Genet. 206:1-8.
92. Nuti, M. P., Lepidi, A. A., Prakash, R. K., Schilperoort R. A., and Cannon, F. C. 1979. Evidence for nitrogen fixation genes on indigenous Rhizobium plasmids. Nature 282:533-535.
93. Otten, L., Conaday, J., Gérard, J. C., Fournier, P., Crouzet, P., and Paulus, F. 1992. Evolution of Agrobacteria and their Ti plasmids. A review. Mol. Plant-Microbe Interact. 5:279-287.
94. Pankhurst, C., Macdonald, P., and Reeves, J. 1986. Enhanced nitrogen fixation and competitiveness for modulation of Lotus pedunculatus by a plasmid-cured derivative of Rhizobium Ion. J. Gen. Microbiol. 132:2321-2328.
95. Pansegrau, W., Lanka, E., Barth, P. T., Figurski, D. H., Guiney, D. G., Haas, D., Helinski, D. R., Schwab, H., Stanisich, V. A., and Thomas, C. M. 1994. Complete nucleotide sequence of Birmingham IncPα plasmids. J. Mol. Biol. 239:623-663.
96. Pardo, M. A., Lagúnez, J., Miranda, J., and Martínez, E. 1994. Nodulating ability of Rhizobium tropici is conditioned by a plasmid-encoded citrate synthase. Mol. Microbiol. 11:315-321.
97. Plazinski, J., Cen, Y. H., and Rolfe, B. G. 1985. General method for the identification of plasmid species in fast-growing soil microorganisms. App. Environ. Microbiol. 48:1001-1003.
98. Prakash, R. K., and Atherly, A. G. 1984. Reiteration of genes involved in symbiotic nitrogen fixation by fast-growing Rhizobium japonicum. J. Bacteriol. 160:785-787.
99. Pretorius-Güth, I. M., Pühler, A., and Simon, R. 1990. Conjugal transfer of megaplasmid 2 between Rhizobium meliloti strains in alfalfa nodules. Appl. Environ Microbiol. 56:2354-2359.
100. Quinto, C., de la Vega, H., Flores, M., Fernández, L., Ballado, T., Soberón, G., and Palacios, R. 1982. Reiteration of nitrogen fixation gene sequences in Rhizobium phaseoli. Nature 299:724-728.
101. Rao, J. R., Fenton, M., and Jarvis, B. D. W. 1994. Symbiotic plasmid transfer in Rhizobium leguminosarum biovar trifolii and competition between the inoculant strain Icmp2163 and transconjugant soil bacteria. Soil Biol. Biochem. 26:339-351.
102. Rastogi, V. K., Bromfield, E. S. P., Whitwill, S. T., and Barran, L. R. 1991. A cryptic plasmid of indigenous Rhizobium meliloti possesses reiterated nodC and nifE genes and undergoes DNA rearrangement. Can. J. Microbiol. 38:563-568.
103. Roberts, R. C., Burioni, R., and Helinski, D. R. 1990 Genetic characterization of the stabilizing functions of a region of broad-host-range plasmid RK2. J. Bacteriol. 172:6204-6216.
104. Romero, D., Brom, S., Martínez-Salazar, J , Girard, M. L., Palacios, R., and Dávila, G. 1991. Amplification and deletion of a nod-nif region in the symbiotic plasmid of Rhizobium phaseoli. J. Bacteriol. 173:2435-2441.
105. Rosenberg, C., Boistard, P , Dénarié, J., and Casse-Delbart, F. 1981. Genes controlling early and late functions in symbiosis are located on a megaplasmid in Rhizobium meliloti. Mol. Gen. Genet. 184:326-333.
106. Ruvkun, G. B., Long, S. R., Meade, H. M., van den Bos, R. C., and Ausubel, F. M. 1982. ISRmI: a Rhizobium meliloti insertion sequence that transposes preferentially into nitrogen fixation genes. J. Mol. Appl. Genet. 1:405-418.
107. Sanjuán, J., and Olivares, J. 1989. Implication of nifA in regulation of genes located on a Rhizobium meliloti cryptic plasmid that affect nodulation efficiency. J. Bacteriol. 171:4154-4161.
108. Sanjuán, J., and Olivares, J. 1991. NifA-NtrA regulatory system activates transcription of nfe, a gene locus involved in nodulation competitiveness of Rhizobium meliloti. Arch. Microbiol. 155:543-548.
109. Saurugger, P. N., Hrabak, O., Schwab, H., and Lafferty, R. M. 1986. Mapping and cloning of the par-region of broad host range plasmid RP4. J. Biotechnol. 4:333-343.
110. Segovia, L., Young, J. P. W., and Martínez-Romero, E. 1993. Reclassification of american Rhizobium leguminosarum biovar phaseoli type 1 strains as Rhizobium etli sp. nov Int. J. Syst. Bacteriol. 43:374-377.
111. Selbitschka, W., and Lotz, W. 1991. Instability of cryptic plasmids affects the symbiotic effectivity of Rhizobium leguminosarum bv. viciae strains. Mol. Plant-Microbe Interact. 4:608-616.
112. Sen, D., Baldani, J. I., and Weaver, R. W. 1990. Expression of heat induced proteins in wild type and plasmid-cured derivatives of Rhizobium leguminosarum bv. Trifolii. Page 583 in: Nitrogen Fixation: Achievements and Objectives. P. M. Gresshoff, L. E. Roth, G. Stacey, and W. E. Newton, ed. Chapman & Hall, London.
113. Sharma, P. K., and Laxminarayana, K. 1989. Effect of high temperature on plasmid curing of Rhizobium spp. in relation to nodulation of pigeonea [Cajanus cajan (L.) Millsp.]. Biol. Fert. Solis 8:75-79.
114. Simon, R., and Priefer, U. B. 1990. Vector technology of relevance to nitrogen fixation research. Paged 13-49 in: Molecular Biology of Symbiotic Nitrogen Fixation. P. M. Gresshoff, ed. CRC Press, Inc., Boca Ratón, FL.
115. Simon, R., Hotte, B., Klauke, B., and Kosier, B. 1991. Isolation and characterization of insertion sequence elements from gram-negative bacteria by using new broad-host-range, positive selection vectors. J. Bacteriol. 173:1502-1508.
116. Skorupska, A., Derylo, M., and Golinowski, W. 1991. The region for exopolysaccharide synthesis in Rhizobium leguminosarum bv. trifolii is located on the non-symbiotic plasmid. Acta Biochem. Pol. 38:423-.
117. Sobral, B. W. S., Honeycutt, R. J., Atherly, A. G., and McClelland, M. 1991. Electrophoretic separation of the three Rhizobium meliloti replicons. J. Bacteriol. 173:5173-5180.
118. Soto, M. J., Zorzano, A., García-Rodríguez, F. M., Mercado-Blanco, J., López-Lara, I. M., Olivares, J., and Toro, N. 1994. Identification of a novel Rhizobium meliloti nodulation efficiency nfe gene homolog of Agrobacterium ornithine cyclodeaminase. Mol. Plant-Microbe Interact. 7:703-707.
119. Soto, M. J., Zorzano, A., Mercado-Blanco, J., Lepek, V., Olivares, J., and Toro, N. 1993. Nucleotide sequence and characterization of Rhizobium meliloti nodulation competitiveness genes nfe. J. Mol. Biol. 229:570-576.
120. Soto, M. J., Zorzano, A., Olivares, J., and Toro, N. 1992a. Nucleotide sequence of Rhizobium meliloti GR4 insertion sequence ISRm3 linked to the nodulation competitiveness locus nfe. Plant Mol. Biol. 20:307-309.
121. Soto, M. J., Zorzano, A., Olivares, J., and Toro, N. 1992b. Sequence of ISRm4 from Rhizobium meliloti strain GR4. Gene 120:125-126.
122. Tabata, S., Hooykaas, P. J. J., and Oka, A. 1989. Sequence determination and characterization of the replicator region in the tumor-inducing plasmid pTiB6S3. J. Bacteriol. 171:1665-1672.
123. Tepfer, D., Goldman, A., Pamboukdjian, N., Maille, M., Lepingle, A., Chevalier, D., Dénarié, J., and Rosenberg, C. 1988. A plasmid of Rhizobium meliloti 41 encodes catabolism of two compounds from root exudate of Calystegium sepium. J. Bacteriol. 170:1153-1161.
124. Thomas, P. M., Golly, K. F., Zyskind, J. W., and Virginia, R A. 1994. Variation of clonal, mesquite-associated rhizobial and bradyrhizobial populations from surface and deep soils by symbiotic gene region restriction-fragment-length-polymorphism and plasmid profile analysis. Appl. Environ. Microbiol. 60:1146-1153.
125. Thurman, N. P., Lewis, D. M., and Jones, D. G. 1985. The relationship of plasmid number to growth, acid tolerance, and symbiotic efficiency in isolates of Rhizobium trifolii. J. Appl. Bacteriol. 58:1-6.
126. Toro, N., and Olivares, J. 1986. Characterization of a large plasmid of Rhizobium meliloti involved in enhacing nodulation. Mol Gen. Genet. 202:331-335.
127. Turner, S. L., and Young, J. P. W. 1995. The replicator region of the Rhizobium leguminosarum. cryptic plasmid pRL8JI. FEMS Microbiol. Lett. 133:53-58.
128. Truchet, G., Rosenberg, C., Vasse, J., Julliot, J. S., Canut, S., and Dénarié, J. 1984. Transfer of Rhizobium meliloti pSym genes into Agrobacterium tumefaciens: host-specific nodulation by atypical infection. J. Bacteriol. 157:134-142.
129. Ulrich, A., and Pünler, A. 1994 The new class-II transposon Tn163 is plasmid-borne in 2 unrelated Rhizobium leguminosarum biovar viciae strains. Mol. Gen. Genet. 242:505-516.
130. Van den Eede, G., Dreyfus, B., Goethals, K., Van Montagu, M., and Holsters, M. 1987. Identification and cloning of nodulation genes from the stem-nodulating bacterium ORS571. Mol. Gen Genet. 206:291-199.
131. Velázquez, E., Mateos, P. F , Pedrero, P., Dazzo, F. B., and Martínez-Molina, E. 1995. Attenuation of symbiotic effectiveness by Rhizobium meliloti SAF22 related to the presence of a cryptic plasmid. Appl. Environ. Microbiol. 61:2033-2036.
132. Villadas, P. J., Vázquez, E., Martínez-Molina, E., and Toro, N. 1995. Identification of nodule dominant Rhizobium meliloti strains carrying pRmeGR4b type plasmid within indigenous soil populations by PCR using derived from specific DNA sequences. FEMS Microbiol. Ecol. 17:161-168.
133. 4-dicarboxylate transport and symbiotic nitrogen fixation are located on a megaplasmid. J. Bacteriol. 170:927-934.
134. Weinstein, M., Roberts, R. C., and Helinski, D. R. 1992. A region of the broad-host-range plasmid RK2 causes stable in planta inheritance of plasmids in Rhizobium meliloti cells isolated from alfalfa root nodules. J. Bacteriol. 174:7486-7489.
135. Wheatcroft, R., and Laberge, S. 1991. Identification and nucleotide sequence of Rhizobium meliloti sequence ISRm3: Similarity between the putative transposase encoded by ISRm3 and those encoded by Staphylococcus aureus IS256 and Thiobacillus ferrooxidans IST2. J. Bacteriol. 173:2530-2538.
136. Wheatcroft, R., and Watson, R. J. 1988. Distribution of insertion sequence ISRm1 in Rhizobium meliloti and other Gram-negative bacteria. J. Gen. Microbiol. 134:113-121.
137. Williams, D. R., and Thomas, C. M. 1992. Active partitioning of bacterial plasmid. J. Gen. Microbiol. 138:1-16.
138. +, a gene involved in lipopolysaccharide biosynthesis. J. Bacteriol. 172:2622-2632.
139. Young, J. P. W., and Wexler, M. 1988. Sym plasmid and chromosomal genotypes are correlated in field populations of Rhizobium leguminosarum. J. Gen. Microbiol. 134:2731-2739.
140. Zhan, H., Levery, S. B., Lee, C. C., and Leigh, J. A. 1989. A second exopolysaccharide of Rhizobium meliloti strain SU47 that can function in root nodule invasion. Proc. Natl. Acad. Sci. USA 86:3055-3059.