水稻黄单胞菌双精氨酸运输(Tat)系统关键基因的克隆与功能分析
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摘要
水稻黄单胞菌包含两个致病变种Xanthomonas orzae pv.oryzae(Xoo)和X.oryzaepv.oryzicola(Xooc),在水稻上分别引起白叶枯病和细菌性条斑病。在本研究中,我们鉴定了水稻白叶枯病菌PXO99菌株和水稻条斑病菌RsGD42菌株的双精氨酸运输(Tat)途径,明确了Tat系统对这两种植物病原菌在游动性,趋化性,胞外多糖和毒力方面的影响。
     (一)根据GeneBank数据库中Xoo KACC10331和MAFF311018的tat基因序列设计引物,采用PCR方法从Xoo PXO99中克隆了tat同源基因,命名为tat_(Xoo)。通过同源重组的方式成功构建了PXO99菌株tatB和tatC基因的插入突变体,经PCR和Southern杂交验证确认。野生型菌株PXO99细胞在0.3%NA软琼脂平板上具有强游动性。而tatB和tatC基因突变体游动性削弱。而且,tatB和tatC基因突变体细胞缺失了鞭毛,并且在有氧条件下都不能对葡萄糖产生趋化应答。这表明,Tat分泌系统与鞭毛的形成和趋化性应答相关。同时tatB和tatC基因突变体减少了胞外多糖的分泌量。另外,与野生型菌株PXO99相比,tatB和tatC基因突变体都极大削弱了在水稻上的毒力。然而,两种突变体仍然能激发非寄主烟草的过敏性反应。结果显示,Tat系统对水稻白叶枯病菌在水稻上的致病力起重要作用。
     (二)根据水稻黄单胞菌tat基因的同源性设计简并引物,采用PCR方法从水稻条斑病菌中克隆了tat同源基因,命名为tat_(Xooc)。通过同源重组构建了RsGD42的tatC基因突变体,经PCR和Southern杂交验证确认。与野生型菌株RsGD42相比,tatC基因突变体并不影响正常生长,并且仍可激发非寄主烟草的过敏性反应。有趣的是,tatC基因突变体缺失鞭毛,极大减弱了游动性。此外,在有氧条件下,该突变体对葡萄糖几乎不产生趋化性应答。明显地,与野生型菌株相比,tatC突变体减少了胞外多糖的分泌量,并且显著削弱了在成熟期水稻上的毒力。结果显示,水稻条斑病菌的Tat系统对其在水稻上的致病力起重要作用。
Xanthomonas oryzae pv.oryzae(Xoo) and X.oryzae pv.oryzicola(Xooc) cause leaf blight and leaf streak on rice respectively.In this study,we identified and characterized the contribution of the twin-arginine translocation(Tat) pathway to motility,chemotaxis, extracellular polysaccharide(EPS) and virulence of the phytopathogens X.oryzae pv. oryzae strain PXO99 and X.oryzae pv.oryzicola strain RsGD42.
     (Ⅰ) A tat homologue,designated tat_(Xoo),was cloned from Xanthomonas oryzae pv. oryzae strain PXO99,with degenerated primers by polymerase amplification reaction (PCR).tatB and tatC disruption mutants of strain PXO99 were successfully generated by a single cross-over event,and confirmed by PCR and Southem blotting.Wild type strain PXO99 cells were highly motile in NYGA 0.3%soft agar medium.In contrast,the tatB and tatC mutation impaired motility.Furthermore,the cells of tatB and tatC mutants lacked detectable flagella and both mutants exhibited almost no chemotaxis toward glucose under aerobic conditions indicating this secretion pathway contributes to flagellar biogenesis and chemotactic responses.It was also obersved that the tatB and tatC mutants exhibited reductive production of extracellular polysaccharide(EPS).In addition,both tatB and tatC mutants of strain PXO99 had significant reduction of virulence on rice when compared with the wild type.However,tatB and tatC mutants still could elicit the hypersensitive response(HR) in nonhost tobacco.Our findings indicated that the Tat system of X.oryzae pv.oryzae played an important role in virulence on rice.
     (Ⅱ) A tat homologue,designated tat_(Xooc),was cloned from Xanthornonas oryzae pv. oryzicola,with degenerated primers by polymerase amplification reaction(PCR).A tatC disruption mutant of strain RsGD42 was constructed by a single cross-over event,and confirmed by PCR and Southern blotting.The tatC mutant was not affected in in vitro growth and induction of hypersensitive response(HR) in nonhost tobacco compared to wild type strain RsGD42.Interestingly,the tatC mutant lacked detectable flagella and highly impaired in motility.Furthermore,the tatC mutant displayed almost no chemotaxis toward glucose under aerobic conditions.Remarkably,it was observed that the tatC mutant exhibited reductive production of extracellular polysaccharide(EPS) and significant reduction of virulence on adult rice plants when compared to wild type strain.Our findings indicated that the Tat system of X.oryzae pv.oryzicola played an important role in virulence on rice.
引文
1. Alami M, TrescherD, Wu LF, et al. Separate Analysis of Twin-arginine Translocation (Tat)-specific Membrane Binding and Translocation in Escherichia coli. Arch Microbiol, 2002, 277:20499-20503
    2. Arlat M, Boucher C. Identification of a dsp DNA region controlling aggressiveness of Pseudomonas solanacearum. MPMI, 1991,4:211-213.
    3. Behrendt J, Standar K, Lindenstrauβ U, et al. Topological studies on the twin-arginine translocase component TatC. FEMS Microbiol Lett, 2004, 234:303-308
    4. Berks BC, Palmer T, Sargent F. The Tat protein translocation pathway and its role in microbial physiology. Adv Microb Physiol, 2003, 47:187-254
    5. Berks BC, Sargent F, Palmer T. The Tat protein export pathway. Mol Microbiol, 2000, 35:260-274
    6. Berks BC. A common export pathway for proteins binding complex redox cofactors? Mol Microbiol, 1996,22:393-404
    7. Boucher CA, Bareris PA, Trigalet AP, et al. Transposon mutagenesis of Pseudomonas solanacearum: isolation of Tn5-induced avirulent mutants. J Gen Microbiol, 1985,131:2449-2457.
    8. Boucher CA, Van GF, Barberis PA. Pseudomonas solanacearum genes controlling both pathogenicity on tomato and hypersensitivity on tobacco are clustered. J Bacteriol, 1987, 169:5626-5632.
    9. Braun EJ. Colonization of resistant and susceptible maize plants by Erwinia stewartii strains differing in exo-polysaccharide production. Physiol Mol Plant Pathol, 1990, 36:363-379
    10. Bronstein PA, Marrichi M, Cartinhour S, et al. Identification of a Twin-Arginine Translocation System in Pseudomonas syringae pv. tomato DC3000 and Its Contribution to Pathogenicity and Fitness. J Bacteriol, 2005,187(24): 8450-8461
    11. Bruce N A, Robert G M, Barbara JG. The First Step of Histidine Biosynthesis. The Journal of Biological Chemistry, 1961, 236(7): 2019-2026
    12. Buchanan G, Sargent F, Berks BC, et al. A genetic screen for suppressors of Escherichia coli Tat signal peptide mutations establishes a critical role for the second arginine within the twin-arginine motif. Arch Microbiol, 2004,177:107-112
    13. Caldelari I, Mann S, Crooks C, Palmer T. The Tat Pathway of the Plant Pathogen Pseudomonas syringae is Required for Optimal Virulence. MPMI, 2006,19(2): 200-212
    14. Carlomagno MS, Chiarotti L, Alifano P, et al. Structure of the Salmonella typhimurium and Escherichia coli K-12 histidine operons. Journal of Molecular Biology, 1988,203:585-606
    15. Charles TC, Nester EW. A chromosomally encoded two-component sensory transduction system is required for virulence of Agrobacterium tumefaciens. J Bacteriol, 1993,175:6614-6625.
    16. Chesnokova O, Coutinho JB, Khan IH, et al. Characterization of flagella genes of Agrobacterium tumefaciens, and the effect of a bald strain on virulence. Mol Microbiol, 1997, 23:579-590.
    17. Choi JH, Lee SY. Secretory and extracellular production of recombinant proteins using Escherichia coli. Appl Microbiol Biotechnol, 2004, 64:625-635
    18. Chua KL, Chan YY, Gan YH. Flagella Are Virulence Determinants of Burkholderia pseudomallei. Infect Immun, 2003, 71 (4): 1622-1629
    19. Coplin DL, Cook D. Molecular genetics of extracellular polysaccharide biosynthesis in vascular phytopathogenic bacteria Mol Plant-Microbe Interact, 1990, 3:271-279
    20. Costacurta A, Vanderleyden J. Synthesis of phytohormones by plant-associated bacteria. Crit Rev Microbiol, 1995,21:1-18.
    21. Cristoal S, de Gier JW, ik Nielsen H, et al. Competition between Sec- and TAT-dependent protein translocation in Escherichia coli. EMBO J, 1999,18:2982-2990
    22. Crooke H, Kidgell C, Boles J, et al. Disruption of the sec-independent twin arginine translocase attenuates the virulence of E. coli K1 and S. typhimurium, but appears to be an essential gene in N. meningitidis. Abstract of Microbial Pathogenesis and Host Response, 2001. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, U.S.A.
    23. Cue D, Beckler G, Reeve J, et al. Structure and sequence divergence of two archaebacterial genes. PNAS, 1985, 81:8019-8023
    24. Cui Y, Chatterjee A, Chatterjee AK. Effects of the two-component system comprising Tat and GacS of Erwinia carotovora subsp. carotovora on the production of global regulatory rsmB RNA, extracellular enzymes, and harpin_(ECC)- MPMI, 2001, 14:516-526.
    25. da Silva, Ferro JA, et al. Comparison of the genome of two Xanthomonas pathogens with differing host specificities. Nature, 2002, 417:459-463.
    26. De Buck E, Lebeau I, Maes L, et al. A putative twin-arginine translocation pathway in Legionella pneumophila. Biochem Biophys Res Commun, 2004, 317:654-661
    27. De Buck E, Maes L, Meyen E, et al. Legionella pneumophila Philadelphia-1 tatB and tatC affect intracellular replication and biofilm formation. Biochem Biophys Res Commun, 2005, 331:1413-1420
    28. De Keersmaeker S, Van Mellaert L, Lammertyn E, et al. Functional analysis of TatA and TatB in Streptomyces lividans. Biochem Biophys Res Commun, 2005,335:973-982
    29. De Leeuw E, Granjon T, Porcelli I, et al. Oligomeric properties and signal peptide binding by Escherichia coli Tat protein transport complexes. J Mol Biol, 2002, 322: 1135-1146
    30. Delorme C, Ehrlich S D, Renault P. Histidine Biosynthesis Genes in Lactococcus lactis subsp. Lactis. Journal of Bacteriology, 1992,147(20):6571-6579
    31. Delorme C, Godon J J, Ehrlich S D, et al. Gene Inactivation in Lactococcus lactis: Histidine Biosynthesis. Journal of Bacteriology, 1993,175 (14):4391-4399.
    32. Denny TP. Involvement of bacterial polysaccharides in plant pathogenesis. Annu Rev Phytopathol, 1995,33:173-197
    33. Dharmapuri S, Sonti RV. A transposon insertion in the gumG homologue of Xanthomonas oryzae pv. oryzae causes loss of extracellular polysaccharide production and virulence. FEMS Microbiol Lett, 1999,179:53-59
    34. Dharmapuri S, Sontir V. A transposon insertion in the gumG homologue of Xanthomonas oryzae pv. oryzae causes loss of extracellular polysaccharide production and virulence. FEMS Microbiol Lett, 1999,179:53-59
    35. Ding ZY, Christie PJ. Agrobacterium tumefaciens Twin-Arginine-Dependent Translocation Is Important for Virulence, Flagellation, and Chemotaxis but Not Type Ⅳ Secretion. J Bacteriol, 2003, 185(3):760-771
    36. Fani R, Li P, Chiarelli IL, et al. The Evolution of the Histidine Biosynthetic Genes in Prokaryotes: A Common Ancestor for the hisA and hisF Genes. Journal of Molecular Evolution, 1994, 38:489-495
    37. Fani R, Mori E, Tamburini E, et al. Evolution of the structure and chromosomal distribution of Histidine biosynthetic genes. Origins of Life and Evolution of the Biosphere, 1998, 28:555-570
    38. Feldman M, Bryan R, Rajan S, et al. Role of Flagella in Pathogenesis of Pseudomonas aeruginosa Pulmonary Infection. Infect Immun, 1998,66 (1): 43-51
    39. Frank T, Ralf K, Thomas B, et al. Insights into genome plasticity and pathogenicity of the plant pathogenic bacterium Xanthomonas campestris pv. vesicatoria revealed by the complete genome sequence. J Bacteriol, 2005,187(21):7254-7266.
    40. Fuqua WC, Winans SC, Greenberg EP. Quorum sensing in bacteria: The LuxR-LuxI family of cell density-responsive transcriptional regulators. J Bacteriol, 1994,176:269-275.
    41. Furutani A, Tsuge S, Tsuno TOK, et al. Hpa1 secretion via type Ⅲ secretion system in Xanthomonas oryzae pv. oryzae. J Gen Plant Pathol. 2003.69:271-275
    42. Grimm C, Aufsatz W, Panopoulos NJ. The hrpRS locus of Pseudomonas syringae pv. phaseolicola constitutes a complex regulatory unit. Mol Microbiol, 1995,15:1551-1561.
    43. Hendrickson EL, Guevera P, Ausubel FM, et al. Virulence of the phytopathogen Pseudomonas syringae pv. maculicola is rpoN dependent. J Bacteriol, 2000,182:3498-3507.
    44. Hirano SS. Bacteria in the leaf ecosystem with emphasis on Pseudomonas syringae— A pathogen, ice nucleus, and epiphyte. Microbiol Mol Biol Rev, 2000,64:624-653.
    45,. Hirokazu O, Yasuhiro I, Masaru T, et al. Genome sequence of Xanthomonas oryzae pv. oryzae suggests contribution of large numbers of effector genes and insertion sequence to its race diversity. JARQ, 2005, 39(4):275-287.
    46. Huang J, Carney BF, Schell MA, et al. A complex netword regulates expression of EPS and other virulence genes of Pseudomonas solanacearum. J Bacteriol, 1995, 177:125912-125867.
    47. Ignatova Z, H(o|¨)rnle C, Nurk A, et al. Unusual Signal Peptide Directs Penicillin Amidase from Escherichia coli to the Tat Translocation Machinery. Biochem Biophys Res Commun, 2002, 291:146-149
    48. Ize B, Gerard F, Wu LF. In vivo assessment of the Tat signal peptide specificity in Escherichia coli. Arch Microbiol, 2002,178:548-553
    49. Jack RL, Buchanan G, Dubini A, et al. Coordinating assembly and export of complex bacterial proteins. EMBO J, 2004, 23:3962-3972
    50. Josenhans C, Suerbaum S. The role of motility as a virulence factor in bacteria. Int J Med Microbiol, 2002,291:605-614
    51. Katzen F, Becker A, Ielmini MV, et al. New Mobilizable Vectors Suitable for Gene Replacement in Gram-Negative Bacteria and Their Use in Mapping of the 3' End of the Xanthomonas campestris pv. campestris gum Operon. AEM, 1999, 65: 278-282
    52. Kearney B, Staskawicz BJ. Widespread distribution and fitness contribution of Xanthomonas campestris avirulence gene avrBs2. Nature, 1990, 346:385-386.
    53. Kitten T, Kinscherf TG, Willis DK, et al. A newly identified regulator is required for virulence and toxin production in Pseudomonas syringae. Mol Microbiol, 1998,28:917-929.
    54. Kleerebezem M, Quadri LE, Kuipers OP, et al. Quorum sensing by peptide pheromones and two-component signal transduction systems in Gram-positive bacteria Mol Microbiol, 1997, 24:895-904.
    55. Klem TJ, Chen Y,Davisson VJ. Subunit Interactions and Glutamine Utilization by Escherichia coli Imidazole Glycerol Phosphate Synthase. Journal of Bacteriology, 2001,182(3):989-996.
    56. Klem TJ, Davisson VJ. Imidazole Glycerol Phosphate Synthase: The Glutamine Amidotransferase in Histidine Biosynthesis. Biochemistry, 1993, 32:5177-5186
    57. Lavander M, Ericsson SK, Broms JE, et al. The Twin Arginine Translocation System Is Essential for Virulenceof Yersinia pseudotuberculosis. Infect Immun, 2006, 74(3):1768—1776
    58. Lazazzera BA, Grossman AD. The ins and outs of peptide signaling. Trends Microbiol, 1998, 6:288-294.
    59. Lee BM, Park YJ, Park DS, et al. The genome sequence of Xanthomonas oryzae pathovar oryzae KACC10331, the bacterial blight pathogen of rice. Nucleic Acids Research, 2005, 33(2):577-586.
    60. Legerton T L, Yanofsky C. Cloning and characterization of the multifunctional his-3 gene of Neurospora crassa. Gene, 1985, 39:129-140
    61. Li HQ, Matsuda I, Fujise Y, et al. Short-chain acyl-CoA-dependent production of oxalate from oxaloacetate by Burkholderia glumae, a plant pathogen which causes grain rot and seedling rot of rice via the oxalate production. J Biochem, 1999, 126:243-253.
    62. Limauro D, Avitabile A, Cappellano C, et al. Cloning and characterization of the histidine biosynthetic gene cluster of Streptomyces coelicolor A3 (2). Gene, 1990, 90:31-41
    63. Mangels D, Mathers J, Bolhuis A, et al. The Core TatABC Complex of the Twin-arginine Translocase in Escherichia coli: TatC Drives Assembly Whereas TatA is Essential for Stability . J Mol Biol, 2005, 345: 415-423
    64. Matthew PD, William EB. Bacterial autoinduction: looking outside the cell for new metabolic engineering targets. Microbial Cell Factories, 2002,1:5-12.
    65. Mazumder R, Phelps TJ, Krieg NR, et al. Determining chemotactic responses by two subsurface microaerophiles using a simplified capillary assay method. J Microbiol Methods, 1999, 37(3):255-263.
    66. Meloni S, Rey L, Sidler S, et al. The twin-arginine translocation (Tat) system is essential for Rhizobium-legume symbiosis. Mol Microbiol, 2003, 48:1195-1207
    67. Mew TW. Current status and future prospects of research on bacterial blight of rice. Ann Rev Phytopatho, 1987,125:539-582.
    68. Miller JH. Experiments in molecular genetics. 1972. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press
    69. Miller MB, Bassler BL. Quorum sensing in bacteria. Annu Rev Microbiol, 2001, 55:165-199.
    70. Miranda RL, Conway T, Leatham MP, et al. Glycolytic and gluconeogenic growth of Escherichia coli O157:H7(EDL933) and E.coli K-12(MG1655) in the mouse intestine. Infect Immun, 2004, 72(3):1666-1676.
    71. Mobley HLT, Belas R, Lockatell V, et al, Trifillis AL, Johnson DE, Warren JW. Construction of a flagellum-negative mutant of Proteus mirabilis: effect on internalization by human renal epithelial cells and virulence in a mouse model of ascending urinary tract infection. Infect Immun, 1996, 64:5332-5340
    72. Nealson KH, Hastings JW. Bacterial bioluminescence: its control and ecological significance. Microbiol Rev, 1979, 43:496-518.
    73. Ochman H, Lawrence JG, Groisman EA. Lateral gene transfer and the nature of bacterial innovation. Nature, 2000, 405:299-304.
    74. Ochman H, Moran N. Genes lost and genes found: evolution of bacterial pathogenesis and symbiosis. Science, 2001,292:1096-1099.
    75. Ochsner UA, Snyder A, Vasil AI, et al. Effects of the twin-arginine translocase on secretion of virulence factors, stress response, and pathogenesis. Proc. Natl. Acad. Sci. U.S.A., 2002, 99:8312-8317
    76. Ovadis M, Liu XG, Gavriel S, et al. The global regulator genes from biocontrol strain Serratia plymuthica IC1270: cloning, sequencing, and functional studies. J Bacteriol, 2004, 186(15):4986~4993.
    77. Palmer T, Berks BC. Moving folded proteins across the bacterial cell membrane. Microbiol, 2003, 149:547-556
    78. Palmer T, Sargent F, Berks BC. Export of complex cofactor containing proteins by the bacterial Tat pathway. Trends Microbiol, 2005,13:175-180
    79. Pan SQ, Charles T, Jin S, et al. Preformed dimeric state of the sensor protein VirA is involved in plant-Agrobacterium signal transduction. PNAS, 1993, 90:9939-9943.
    80. Pradel N, Ye C, Livrelli V, et al. Contribution of the twin arginine translocation system to the virulence of enterohemorrhagic Escherichia coli O157:H7. Infect Immun, 2003, 71:4908-4916
    81. Ragan MA. Detection of lateral gene transfer among microbiol genomes. Curr Opin Genet Dev, 2001,11:620-628.
    82. Ray SK, Rajeshwari R, Sharma Y, et al. A high molecular-weight outer membrane protein of Xanthomonas oryzae pv. oryzae exhibits similarity to non-fimbrial adhesins of animal pathogenic bacteria and is required for optimum virulence. Mol Microbiol, 2002,46: 637-647.
    83. Ray SK, Rajeshwari R, Sonti RV. Mutants of Xanthomonas oryzae pv. oryzae deficient in general secretory pathway are virulence deficient and unable to secrete xylanase. MPMI, 2000,13:394-401.
    84. Rieder G, Merrick M J, Castorph H, et al. Function of hisF and hisH Gene Products in Histidine Biosynthesis. The Journal of Biological Chemistry, 1994, 269(20): 14386-14390
    85. Rossier O, Cianciotto NP. The Legionella pneumophila tatB gene facilitates secretion of phospholipase C, growth under iron-limiting conditions, and intracellular infection. Infect Immun, 2005, 73:2020-2032
    86. Salzberg SL, Sommer DD, Schatz MC, et al. Genome sequence and rapid evolution of the rice pathogen Xanthomonas oryzae pv. oryzae PXO99A. BMC Genomics, 2008,9:204
    87. Sambrook J, Russell D W. Molecular Cloning: A Laboratory Manual [M]. 3rd. New York: Cold Sp ring Harbour Laboratory Press, 2001
    88. Sanders C, Wethkamp N, Lill H. Transport of cytochrome c derivatives by the bacteria] Tat protein translocation system. Mol Microbiol, 2001,41:241-246
    89. Sargent F, Gohlke U, De Leeuw E, et al. Purified components of the Escherichia coli Tat protein transport system form a double-layered ring structure. Eur J Biochem, 2001, 268:3361-3367
    90. Schell MA. Regulation of virulence and pathogenicity genes in Ralstonia solanacearum by a complex network. Annu Rev Phytopathol, 2000, 38:263-292.
    91. Skorn M, Siritida R, Rojana S, et al. Construction and physiological analysis of a Xanthomonas oryzae pv. oryzae recA mutant. FEMS Microbiol Lett, 1998,169:269-275.
    92. Stanley NR, Findlay K, Berks BC, et al. Escherichia coli Strains Blocked in Tat-Dependent Protein Export Exhibit Pleiotropic Defects in the Cell Envelope. J Bacteriol, 2001,183:139-144
    93. Stanley NR, PalmerT, Berks BC. The Twin Arginine Consensus Motif of Tat Signal Peptides Is Involved in Sec-independent Protein Targeting in Escherichia coli. J Biol Chem, 2000, 275(16):11591-11596
    94. Stepansky A, Leustek T. Histidine biosynthesis in plants. Amino Acids 2006, 30: 127-142 Sthrul K. Nucleotide sequence and transcriptional mapping of the yeast pet56-his3-ded1 gene region. Nucleic Acids Research, 1985,13:8587-8601
    95. Tang JL, Feng JX, Li QQ, et al. Cloning and characterization of the rpfC gene of Xanthomonas oryzae pv. oryzae: Involvement in exopolysaccharide production and virulence to rice. MPMI, 1996, 9: 664-666.
    96. Tang JL, Liu YN, Daniels MJ, et al. Genetic and molecular analysis of a cluster of rpf genes involved in positive regulation of synthesis of extracellular enzymes and polysaccharide in Xanthomonas campestris pathovar campestris.Mol Gen Genet,1991,226:409-417.
    97.Vojnov AA,Slater H,Daniels M J,et al.Expression of the gum operon directing xanthan biosynthesis in Xanthomonas campestris and its regulation in planta.Mol Plant-Microbe Interact,2001,14:768-774
    98.Voulhoux R,Ball G,Ize B,et al.Involvement of the twin-arginine translocation system in protein secretion via the type Ⅱ pathway.EMBO J,2001,20:6735-6741
    99.Wei Q,Yantao J,Shuangxi R,et al.Comparative and functional genomic analyses of the pathogenicity of phytopathogen Xanthornonas campestris pv.campestris.Genome Research,2005,15:757-767.
    100.Wei Z,Beer SV.hrp L activates Erwinia amylovora hrp gene transcription and is a member of the ECF subfamily of sigma factors.J Bacteriol,1995,177:6201-6210.
    101.Wei Z,Kim JF,Beer SV.Regulation of hrp genes and type Ⅲ protein secretion in Erwinia amylovora by HrpX/HrpY,a novel two-component system and HrpS.MPMI,2000,13:1251-1262.
    102.Weil C,Beckler G,Reeve J.Structure and organization of the his A gene of the thermophilic archaebacterium Methanococcus thermolithotrophicus.Journal of Bacteriology,1987,169:4857-4860
    103.Winzer K,Hardie KR,Burgess N,et al.LuxS:its role in central metabolism and the in vitro synthesis of 4-hydroxy-5-methyl-3(2H)-furanone.Microbiol,2002,148:909-922.
    104.Wosten MM.Eubacterial sigma-factors.FEMS Microbiol Rev,1998,22:127-150.
    105.Wren BW.Microbiol genome analysis:insights into virulence,host adaptation and evolution.Nat Rev Genet,2000,1:30-39.
    106.Wu LF,Chanal A,Rodrigue A.Membrane targeting and translocation of bacterial hydrogenases.Arch Microbiol,2000,173:319-24
    107.Xiao Y,Heu S,Yi J,et al.Identification of a putative alternate sigma factor and characterization of a multicomponent regulatory cascade controlling the expression of Pseudomonas syringae pv.syringae Pss61 hrp and hrm A genes.J Bacteriol,1994,176:1025-1036.
    108.Yang B,Zhu W,Johnson LB,et al.The virulence factor AvrXa7 of Xanthomonas oryzae pv.oryzae is a type Ⅲ secretion pathway-dependent nuclear-localized double-stranded DNA-binding protein.PNAS,2000,97:9807-9812.
    109.Yu J,Penaloza-Vazquez A,Chakrabarty AM,et al.Involvement of the exopolysacharide alginate in the virulence and epiphytic fitness of Pseudomonas syringae pv.syringae.Mol Microbiol,1999,33:712-720
    110.Zhu W,MaGbanua MM,White FF.Identification of two novel hrp-associated genes in the hrp gene cluster ofXanthomonas oryzae pv.oryzae.J Bacteriol,2000,2:1844-1853
    111.陈功友.水稻黄单胞菌(Xanthomonas oryzae)hrp 基因克隆与特性研究.南京:南京农业大学.2000.博士学位论文
    112.成国英,林梅根,侯著卫.稻细条病菌在病残体上的越冬及越冬病田中稻株发病情况调查,湖 北植保,1996,4:21-22。
    113.方中达,任欣正,陈泰英,等.水稻白叶枯病及条斑病和李氏禾条斑病病原细菌的比较研究.植物病理学报,1957,3(2):99-122
    114.方中达.植病研究方法.中国农业出版社,1998
    115.李恒聪.野油菜黄单胞菌锌吸收调控蛋白的调控机理研究.广西大学,2005,硕士学位论文
    116.李建仁,李碧文.水稻细菌性条斑病发生规律及防治措施研究.湖南农业科学,1989,(4):31-33
    117.梁莹.水稻黄单胞菌水稻致病变种与致病相关的新基因的功能鉴定.广西大学,2004,硕士学位论文
    118.许志刚,刘风权,沈秀萍,等.水稻白叶枯病和条斑病的流行与预测(综述).西南农业大学学报,1998,20(5):567-572
    119.邹华松.水稻黄单胞菌(Xanthomonas oryzae)pig和hrp基因的克隆与鉴定.南京农业大学,2002,博士学位论文

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