水稻白叶枯病菌转录调控因子FleQxoo和σ~（54）因子RpoNxoo的基因功能鉴定
|
摘要
细菌鞭毛不仅在适应环境、寻找营养和躲避不良因素伤害等过程中是一种重要的运动器官,而且在趋化、附着、毒性因子产生、生物膜形成和定殖等过程中也是一种潜在的致病因子。细菌鞭毛的生物合成受到级联调控系统的严格控制。在一些重要的动物和医学病原细菌(如铜绿假单胞、霍乱弧菌和幽门螺旋杆菌等)中,存在一个以转录调控因子FleQ和σ~(54)因子RpoN为主控因子的4层级联调控系统,FleQ和σ~(54)因子协同调控了不同类型鞭毛基因的表达。
水稻白叶枯病菌(Xanthomonas oryzae pv. oryzae,简称Xoo)侵染引起的白叶枯病是世界水稻生产上最严重的细菌病害之一,也是病原物—植物互作研究的一种重要模式系统。Xoo单根极生鞭毛是重要的运动器官和潜在的致病因子。然而,至今对Xoo鞭毛生物合成的调控机理尚不清楚。对Xoo基因组进行生物信息学分析,发现了由大约60个基因组成了鞭毛基因簇,其结构排列、序列特征、转录单元和转录方向与铜绿假单胞等相似,其中存在FleQ和RpoN同源序列FleQxoo和RpoNxoo。推断Xoo可能同样存在一个以FleQxoo和RpoNxoo为主控因子的级联调控系统。
本研究通过基因克隆、序列分析、缺失突变、表型测定、鞭毛基因和TTSS基因表达检测,对FleQxoo和RpoNxoo的分子特征及其功能进行了鉴定分析。研究目的和意义在于阐明FleQxoo和RpoNxoo在Xoo鞭毛运动性以及相关生物学性状表达中的作用;阐明Xoo鞭毛系统调控机制将为发展新型、有效和可持续的病害控制策略和方法提供科学依据。
以Xoo野生型菌株PXO99~A基因组DNA为模板,用特异性引物进行PCR扩增,成功地获得了与GenBank中KACC10331序列完全一致的fleQxoo (1485bp)和rpoNxoo (1402bp)基因片段。FleQxoo是NtrC家族激活蛋白成员之一,具有与σ~(54)作用的结构域和DNA结合保守结构域(HTH),通过结合靶基因启动子区域、激活基因的转录。RpoNxoo具有与激活子互作的结构域(AID)、核心结合结构域(CBD)和DNA结合结构域(DBD)的3个保守结构域。FleQ和RpoN在植物病原黄单胞菌(水稻白叶枯病菌、柑桔溃疡病菌、番茄斑点病菌、甘蓝黑腐病菌)中同源性较高,氨基酸序列同源性可达到81.06-98.08%。
采用基因标记置换方法,将构建的基因缺失突变载体pKS-fleQG和pKS-rpoNG分别导入PXO99~A,发生同源重组和标记双交换,分别从基因组中缺失了fleQxoo和rpoNxoo,获得了△fleQxoo和△rpoNxoo缺失突变体。将构建的互补载体pHM-fleQ和pHM-rpoN分别转化到相应的突变体中,获得了互补菌株△fleQxoo::C和△rpoNxoo::C。
与PXO99~A相比,△fleQxoo、△rpoNxoo和△fleQxoo+△rpoNxoo鞭毛产生能力丧失,运动性减弱,基因互补可以使之恢复;但胞外酶类(纤维素酶和木聚糖酶)活性以及对烟草叶组织的致敏性无明显改变。表明FleQxoo和σ~(54)可能主要参与了Xoo鞭毛生物合成及其运动性的调控。
利用生物信息学方法,鉴定了44个σ~(54)依赖型鞭毛基因,其启动子中存在σ~(54)识别的保守结合域GG-(N10)-GC和FleQxoo结合位点保守序列CC-(N4)-C-(N3)-T。鉴定了3个σ~(28)依赖型基因(fliCxoo、cheAxoo和cheZxoo),其启动子中存在σ~(28)识别的保守结合域TAAA-(N15)-GCCCGTT。利用RT-Q-PCR方法,检测了△fleQxoo和△rpoNxoo中6个鞭毛基因(包括自身基因fleQxoo和rpoNxoo、σ~(54)依赖型鞭毛基因fliAxoo、fliDxoo和fliLxoo、σ~(28)依赖型鞭毛基因fliCxoo)的转录。与PXO99~A相比,在所有突变体中这些鞭毛基因的表达均显著降低。表明FleQxoo和RpoNxoo不仅直接正向调控了鞭毛基因fliAxoo、fliDxoo和fliLxoo的转录,通过FliAxoo (σ~(28))间接正向调控了鞭毛素基因fliCxoo的转录,而且还负向调控了自身基因fleQxoo和rpoNxoo的转录。
此外,利用RT-Q-PCR方法,检测了△fleQxoo和△rpoNxoo中3个TTSS基因(转录调控基因hrpG、hrpXo和效应子基因hpaI)的转录。与PXO99~A相比,在所有突变体中这些TTSS基因的表达均显著增加。表明FleQxoo和RpoNxoo负向调控了TTSS基因(hrpG、hrpXo和hpa I)的转录。
总之,本研究阐明了FleQxoo和RpoNxoo (σ~(54))作为主控因子,在Xoo鞭毛生物合成、运动性及其基因表达中起重要的调控作用,揭示了Xoo可能存在一个以FleQxoo和RpoNxoo (σ~(54))为一级调控因子、FliAxoo (σ~(28))为二级调控因子的鞭毛基因级联调控系统。
Flagellum is one of the major bacterial organelles for motility by using which bacteria swim in a liquid environment and swarm over a semisolid surface. In addition to these well-established functions, it has been demonstrated in many pathogenic bacteria that flagella play multiple roles in adhesion, biofilm formation, chemotaxis, colonization and invasion in the pathogenesis. The biosynthesis of flagella is tightly and hierarchically regulated. In some of the important animal and human pathogenic bacteria including Pseudomonas aeruginosa, Vibrio spp. and Helicobater pylori, there is a four-tiered transcription regulation hierarchy mainly controlled by the transcriptional regulator FleQ and the alternative sigma factorσ~(54).
Bacterial blight of rice caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most important diseases that constrain production of this staple crop in many parts of the world. The disease system becomes one of the models to study the plant-pathogen interactions. Although it has been shown that single polar flagellum of Xoo is one of the most important factors in virulence, the regulation of bacterial flagellation is still unknown. Genomic analysis of Xoo revealed that about 60 flagellar genes are clustered, and fleQ homologue (fleQxoo) and rpoN homologue (rpoNxoo) was found. There seems to be a N-tiered transcriptional regulatory circuit with FleQxoo and RpoNxoo (σ~(54)), both of which function as the master regulators in Xoo.
Molecular identification and characterization of fleQxoo and rpoNxoo was performed through gene cloning, sequencing, deletion and expression analysis. The goal is to better understand the role of FleQxoo and RpoNxoo in bacterial behavier (such as motility and virulence/pathogenicity) and to help develop the more innovative, effective and durable strategies for the disease control.
FleQxoo and rpoNxoo was cloned from the genomic DNA of the wild-type PXO99~A. FleQxoo, an NtrC family activator protein, was structurally featured in theσ~(54)-interacting domain and DNA-binding domain with a helix-turn-helix motif, which serves as a cognate activator ofσ~(54) in transcription from severalσ~(54)-dependent promoters of flagellar genes. RpoNxoo had three conserved domains including the activator interacting domain (AID), core binding domain (CBD) and DNA binding domain (DBD). FleQ and RpoN were found highly conserved in plant-pathogenic Xanthomonas spp. with 81.06-98.08% of amino acid homolegous, respectively.
△fleQxoo and△rpoNxoo, the gene deletion mutants were constructed after a double crossover recombination event between Gentamycin resistance gene (GmR) and fleQxoo or rpoNxoo through the marker exchange. Both mutants were non-flagellated and attenuated in flagellar motility on the semi-solid medium, which can be restored by complementation with fleQxoo and rpoNxoo, respectively. Moreover, no significant changes in production of extracellular cellulase and xylanase in vitro, in pathogenicity on rice and induction of hypersensitive response (HR) on non-host tobacco were observed in both mutants compared to PXO99~A.
Putative sequences with consensus to GG-(N10)-GC and CC-(N4)-C-(N3)-T of RpoNxoo- and FleQxoo-binding sites were identified from the promoters of flagellar genes. Putative sequence with consensus to TAAA-(N15)-GCCCGTT ofσ~(28)-binding sites was identified from the promoters of 3 genes (fliAxoo, cheAxoo and cheWxoo). Real-time quantitative PCR analysis of the transcription of 6 flagellar genes (fleQxoo, rpoNxoo, fliAxoo, fliCxoo, fliDxoo and fliLxoo) in△fleQxoo and△rpoNxoo indicates that both FleQxoo and RpoNxoo not only up-regulate the transcription of fliAxoo, fliDxoo and fliLxoo directly and up-regulate fliCxoo through the control of fliAxoo indirectly, but also down-regulate theirself.
In addition, 3 genes involved in TTSS (hrpG, hrpXo and hpaI) are up-regulated remarkably in△fleQxoo and△rpoNxoo compared to PXO99~A, suggesting both FleQxoo and RpoNxoo repress hrpG, hrpXo and hpaI genes.
In summary, both FleQxoo and RpoNxoo as the major regulators play important roles of flagellation and motility in Xoo. It is suggested that there is likely a transcription regulation hierarchy controlled by the transcriptional regulator FleQxoo and the sigma factorsσ~(54) andσ~(28) in Xoo.
水稻白叶枯病菌(Xanthomonas oryzae pv. oryzae,简称Xoo)侵染引起的白叶枯病是世界水稻生产上最严重的细菌病害之一,也是病原物—植物互作研究的一种重要模式系统。Xoo单根极生鞭毛是重要的运动器官和潜在的致病因子。然而,至今对Xoo鞭毛生物合成的调控机理尚不清楚。对Xoo基因组进行生物信息学分析,发现了由大约60个基因组成了鞭毛基因簇,其结构排列、序列特征、转录单元和转录方向与铜绿假单胞等相似,其中存在FleQ和RpoN同源序列FleQxoo和RpoNxoo。推断Xoo可能同样存在一个以FleQxoo和RpoNxoo为主控因子的级联调控系统。
本研究通过基因克隆、序列分析、缺失突变、表型测定、鞭毛基因和TTSS基因表达检测,对FleQxoo和RpoNxoo的分子特征及其功能进行了鉴定分析。研究目的和意义在于阐明FleQxoo和RpoNxoo在Xoo鞭毛运动性以及相关生物学性状表达中的作用;阐明Xoo鞭毛系统调控机制将为发展新型、有效和可持续的病害控制策略和方法提供科学依据。
以Xoo野生型菌株PXO99~A基因组DNA为模板,用特异性引物进行PCR扩增,成功地获得了与GenBank中KACC10331序列完全一致的fleQxoo (1485bp)和rpoNxoo (1402bp)基因片段。FleQxoo是NtrC家族激活蛋白成员之一,具有与σ~(54)作用的结构域和DNA结合保守结构域(HTH),通过结合靶基因启动子区域、激活基因的转录。RpoNxoo具有与激活子互作的结构域(AID)、核心结合结构域(CBD)和DNA结合结构域(DBD)的3个保守结构域。FleQ和RpoN在植物病原黄单胞菌(水稻白叶枯病菌、柑桔溃疡病菌、番茄斑点病菌、甘蓝黑腐病菌)中同源性较高,氨基酸序列同源性可达到81.06-98.08%。
采用基因标记置换方法,将构建的基因缺失突变载体pKS-fleQG和pKS-rpoNG分别导入PXO99~A,发生同源重组和标记双交换,分别从基因组中缺失了fleQxoo和rpoNxoo,获得了△fleQxoo和△rpoNxoo缺失突变体。将构建的互补载体pHM-fleQ和pHM-rpoN分别转化到相应的突变体中,获得了互补菌株△fleQxoo::C和△rpoNxoo::C。
与PXO99~A相比,△fleQxoo、△rpoNxoo和△fleQxoo+△rpoNxoo鞭毛产生能力丧失,运动性减弱,基因互补可以使之恢复;但胞外酶类(纤维素酶和木聚糖酶)活性以及对烟草叶组织的致敏性无明显改变。表明FleQxoo和σ~(54)可能主要参与了Xoo鞭毛生物合成及其运动性的调控。
利用生物信息学方法,鉴定了44个σ~(54)依赖型鞭毛基因,其启动子中存在σ~(54)识别的保守结合域GG-(N10)-GC和FleQxoo结合位点保守序列CC-(N4)-C-(N3)-T。鉴定了3个σ~(28)依赖型基因(fliCxoo、cheAxoo和cheZxoo),其启动子中存在σ~(28)识别的保守结合域TAAA-(N15)-GCCCGTT。利用RT-Q-PCR方法,检测了△fleQxoo和△rpoNxoo中6个鞭毛基因(包括自身基因fleQxoo和rpoNxoo、σ~(54)依赖型鞭毛基因fliAxoo、fliDxoo和fliLxoo、σ~(28)依赖型鞭毛基因fliCxoo)的转录。与PXO99~A相比,在所有突变体中这些鞭毛基因的表达均显著降低。表明FleQxoo和RpoNxoo不仅直接正向调控了鞭毛基因fliAxoo、fliDxoo和fliLxoo的转录,通过FliAxoo (σ~(28))间接正向调控了鞭毛素基因fliCxoo的转录,而且还负向调控了自身基因fleQxoo和rpoNxoo的转录。
此外,利用RT-Q-PCR方法,检测了△fleQxoo和△rpoNxoo中3个TTSS基因(转录调控基因hrpG、hrpXo和效应子基因hpaI)的转录。与PXO99~A相比,在所有突变体中这些TTSS基因的表达均显著增加。表明FleQxoo和RpoNxoo负向调控了TTSS基因(hrpG、hrpXo和hpa I)的转录。
总之,本研究阐明了FleQxoo和RpoNxoo (σ~(54))作为主控因子,在Xoo鞭毛生物合成、运动性及其基因表达中起重要的调控作用,揭示了Xoo可能存在一个以FleQxoo和RpoNxoo (σ~(54))为一级调控因子、FliAxoo (σ~(28))为二级调控因子的鞭毛基因级联调控系统。
Flagellum is one of the major bacterial organelles for motility by using which bacteria swim in a liquid environment and swarm over a semisolid surface. In addition to these well-established functions, it has been demonstrated in many pathogenic bacteria that flagella play multiple roles in adhesion, biofilm formation, chemotaxis, colonization and invasion in the pathogenesis. The biosynthesis of flagella is tightly and hierarchically regulated. In some of the important animal and human pathogenic bacteria including Pseudomonas aeruginosa, Vibrio spp. and Helicobater pylori, there is a four-tiered transcription regulation hierarchy mainly controlled by the transcriptional regulator FleQ and the alternative sigma factorσ~(54).
Bacterial blight of rice caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most important diseases that constrain production of this staple crop in many parts of the world. The disease system becomes one of the models to study the plant-pathogen interactions. Although it has been shown that single polar flagellum of Xoo is one of the most important factors in virulence, the regulation of bacterial flagellation is still unknown. Genomic analysis of Xoo revealed that about 60 flagellar genes are clustered, and fleQ homologue (fleQxoo) and rpoN homologue (rpoNxoo) was found. There seems to be a N-tiered transcriptional regulatory circuit with FleQxoo and RpoNxoo (σ~(54)), both of which function as the master regulators in Xoo.
Molecular identification and characterization of fleQxoo and rpoNxoo was performed through gene cloning, sequencing, deletion and expression analysis. The goal is to better understand the role of FleQxoo and RpoNxoo in bacterial behavier (such as motility and virulence/pathogenicity) and to help develop the more innovative, effective and durable strategies for the disease control.
FleQxoo and rpoNxoo was cloned from the genomic DNA of the wild-type PXO99~A. FleQxoo, an NtrC family activator protein, was structurally featured in theσ~(54)-interacting domain and DNA-binding domain with a helix-turn-helix motif, which serves as a cognate activator ofσ~(54) in transcription from severalσ~(54)-dependent promoters of flagellar genes. RpoNxoo had three conserved domains including the activator interacting domain (AID), core binding domain (CBD) and DNA binding domain (DBD). FleQ and RpoN were found highly conserved in plant-pathogenic Xanthomonas spp. with 81.06-98.08% of amino acid homolegous, respectively.
△fleQxoo and△rpoNxoo, the gene deletion mutants were constructed after a double crossover recombination event between Gentamycin resistance gene (GmR) and fleQxoo or rpoNxoo through the marker exchange. Both mutants were non-flagellated and attenuated in flagellar motility on the semi-solid medium, which can be restored by complementation with fleQxoo and rpoNxoo, respectively. Moreover, no significant changes in production of extracellular cellulase and xylanase in vitro, in pathogenicity on rice and induction of hypersensitive response (HR) on non-host tobacco were observed in both mutants compared to PXO99~A.
Putative sequences with consensus to GG-(N10)-GC and CC-(N4)-C-(N3)-T of RpoNxoo- and FleQxoo-binding sites were identified from the promoters of flagellar genes. Putative sequence with consensus to TAAA-(N15)-GCCCGTT ofσ~(28)-binding sites was identified from the promoters of 3 genes (fliAxoo, cheAxoo and cheWxoo). Real-time quantitative PCR analysis of the transcription of 6 flagellar genes (fleQxoo, rpoNxoo, fliAxoo, fliCxoo, fliDxoo and fliLxoo) in△fleQxoo and△rpoNxoo indicates that both FleQxoo and RpoNxoo not only up-regulate the transcription of fliAxoo, fliDxoo and fliLxoo directly and up-regulate fliCxoo through the control of fliAxoo indirectly, but also down-regulate theirself.
In addition, 3 genes involved in TTSS (hrpG, hrpXo and hpaI) are up-regulated remarkably in△fleQxoo and△rpoNxoo compared to PXO99~A, suggesting both FleQxoo and RpoNxoo repress hrpG, hrpXo and hpaI genes.
In summary, both FleQxoo and RpoNxoo as the major regulators play important roles of flagellation and motility in Xoo. It is suggested that there is likely a transcription regulation hierarchy controlled by the transcriptional regulator FleQxoo and the sigma factorsσ~(54) andσ~(28) in Xoo.
引文
1. 方中达. 中国水稻白叶枯病菌致病类型的研究. 植物病理学报, 1990, 20:81-87.
2. 赖世龙, 侯浩, 姜伟. 细菌的运动性及其在治病初期过程中的作用. 微生物学杂志, 2006, 26(5):68-70.
3. 李任峰, 何启盖, 周锐, 陈焕春.细菌鞭毛概况研究及进展. 微生物学通报, 2005, 32(6):124-127.
4. 章琦. 我国水稻白叶枯病抗性基因的利用及策略. 植物保护学报, 1995, 22(3):241-246
5. 朱友林. 水稻白叶枯病菌诱导水稻悬浮细胞防卫基因表达的初步研究.植物病理学报. 1997, 27:250.
6. Aldridge P, Hughes KT. How and when are substrates selected for type Ⅲ secretion. Trends in Microbiology, 2001, 9:209-214.
7. Alan JW, Karen LV. Get the message out: cyclic-di-GMP regulates multiple levels of flagellum-based motility. Journal of Bacteriology, 2008, 190(2): 463-475.
8. Amati G, Bisicchia P, Galizzi A. DegU-P represses expression of the motility fla-che operon in Bacillus subtilis. Journal of Bacteriology, 2004, 186:6003-6014.
9. Anderson PE, Gober JW. FlbT, the posr-transcriptional regulator of flagellin synthesis in Caulobacter crescentus, interacts with the 5′-untranslated region of flagellin mRNA. Molecular Microbiology, 2000, 38:41-52.
10. Andro T, Chambost JP, Kotoujansky A., et al. Mutants of Erwinia chrysanthemi defective in secretion of pectinase and cellulase. Journal of Bacteriology, 1984, 160(3):1199-1203.
11. Arora SK, Ritchings BW, Almira EC, et al. A transcriptional activator, FleQ, regulates mucin adhesion and flagellar gene expression in Pesudomonas aeruginosa in a cascade manner. Journal of Bacteriology, 1997, 179:5574-5581.
12. Auvray F, Thomas J, Fraser GM, et al. Flagellin polymerization control by a cytosolic export chaperone. Journal of Molecular Biology, 2001, 308:221-229.
13. Beier D, Frank R. Molecular characterization of two-component systems of Helicobacter pylori. Journal of Bacteriol, 2000, 182:2068-2076.
14. Bennet JC, Thomas J, Fraser GM, et al. Substrate complexes and domain organization of the Salmonella flagellar export chaperones FlgN and FliT. Molecular Microbiol, 2001, 39:781-791.
15. Bennet JC, Hughes C. From flagellum assembly to virulence: the extended family of type Ⅲ export chaperones. Trends in Microbiology, 2000, 8:202-204.
16. Buell CR., Joardar V., Lindeberg M., et al. The complete genome sequence of the Arabidopsis and tomato pathogen Pseudomonas syringae pv. tomato DC3000. Proceedings of National Academy of Sciences, 2003, 100:10181-10186.
17. Campos A, Matsumura P. Extensive alaine scanning reveals protein-protein and protein-DNA interaction surfaces in the global regulator FlhD from Escherichia coli. Molecular Microbiol, 2001,39: 581-594
18. Campos A, Zhang R, Alkire R, et al. Crystal structure of the global regulator FlhD from Escherichia coli at 1.8? resolution. Molecular Microbiol, 2001, 39:567-580.
19. Chilcott GS, Hughes KT. Coupling of flagellar gene expression to flagellar assembly in Salmonella enterica Serovar typhiumrium and Escherichia coli. Microbiol Molecular Biology Review, 2000, 64:694-708.
20. Claret L, Hughes C. Functions of the subunits in the FlhD2C2 transcriptional master regulator of bacterial flagellum bilgenesis and swarming. Journl of Molecular Biolology, 2000, 303:467-478.
21. Claret L, Hughes C. Interaction of the atypical prokaryotic transcription activator FlhD2C2 with early promoters of the flagellar gene hierarchy. Journl of Molecular Bilology, 2002, 321:185-199.
22. Correa NE, Peng F, Klose KE. Roles of the regulatory proteins FlhF and FlhG in the Vibrio cholerae flagellar transcription hierarchy. Journal of Bacteriology, 2005, 187:6324-6332.
23. Curtis L C. Deleterious effects of guttated fluid on foliage. American journal of bioethis, 1943, 30: 778–781
24. da Silva AC, Ferro JA, Reinach FC, et al. Comparison of the genomes of two Xanthomonas pathogens with differing host specificities. Nature, 2002, 417 (6887): 459-463.
25. da Silva FG, Shen Y, Dardick C, et al. Bacterial genes involved in type I secretion and sulfation are required to elicit the rice Xa21-mediated innate immune response. Moecularl Plant-Microbe Interaction, 2004, 17:593-601
26. Darwin KH, Miller VL. Type Ⅲ secretion chaperone-dependent regulation: activation of virulence genes by SicA and InvF in Salmonella typhimurium. The EMBO Journal, 2001, 20:1850-1862.
27. Dasgupta N, Ramphal R. Interaction of the antiactivator FleN with the transcriptional activator FleQ regulates flagellar number in Pseudomonas aeruginosa. Journal of Bacteriology, 2001, 183:6636-6644.
28. David O, Ronald PC, Bogdanove AJ, et al. Xanthomonas oryzae pathovars: model pathogens of a model crop. Molecular Plant Pathology, 2006, 7(5): 303-324.
29. Dow JM, Osbourn AE, Wilson TJ, et al. A locus determining pathogenicity of Xanthomonas campestris is involved in lipopolysaccharide biosynthesis. Molecular Plant-Microbe Interaction, 1995, 8:768-777.
30. Dutton RJ, Xu Z, Gober JW. Linking structural assembly to gene expression: a novel mechanism for regulating the activity of a sigma transcription factor. Molecular Microbiology, 2005, 58:743-757.
31. England JC, Gober JW. Cell cycle control of cell morphogenesis in Caulobacter. Current Opinion in Microbiol, 2001, 4: 674-680
32. Ezuka A, Kaku H. A historical review of bacterial blight of rice. Plant Molecular Biology, 2000, 15:53-54.
33. Fenselau S, Bonas U. Sequence and expression analysis of the hrpB pathogenicity operon of Xanthomonas campestris pv. vesicatoria which encodes eight proteins with similarity to components of the Hrp, Ysc, Spa, and Fli secretion systems. Molecular Plant-Microbe Interaction, 1995, 8: 845-854.
34. Francis MS, Lloyd SA, Wolf-Watz H. The type Ⅲ secretion chaperone LcrH co-operates with YopD to establish a negative, regulatory loop for control of Yop synthesis in Yersinis psuedotuberculosis. Molecular Microbiology, 2001, 42:1075-1093.
35. Fraser GM, Bennett JC, Hughes C. Substrate-specific binding of hook-associated proteins by FlgN and FliT, putative chaperones for flagellum assembly. Molecular Microbiology, 1999, 32:569-580.
36. Gu KY, Yang B, Tian D, et al. R gene expression induced by a type-III effector triggers disease resistance in rice. Nature, 2005, 435:1122-1125.
37. He SY. Type III protein secretion systems in plant and animal pathogenic bacteria. Annual Review of Phytopathology, 1998, 36:363-392.
38. Hirokazu O, Yasuhiro I, Masaru T. Genome sequence of Xanthomonas oryzae pv. oryzae suggests contribution of large numbers of effector genes and insertion sequences to its race diversity. Japan Agricultural Research Quarterly, 2005, 39(4): 275-287.
39. Hopkins CM, White FF, Choi SH, et al. Identification of a family of avirulence genes from Xanthomonas oryzae pv. oryzae. Molecular Plant-Microbe Interaction, 1992, 5(6): 451-459.
40. Hu RM, Yang TC, Yang SH, et al. Deduction of upstream sequences of Xanthomonas campestris flagellar genes responding to transcription activation by FleQ. Biochemical and Biophysical Research Communication. 2005, 335: 1035-1043.
41. Iyer AS, McCouch SR. The rice bacterial blight resistance gene xa5 encodes a novel form of disease resistance. Molecular Plant-Microbe Interaction, 2004, 17:1348-1354.
42. Karlinsey JE, Lonner J, Brown KL, et al. Translation/secretion coupling by type Ⅲ secretion systems. Cell, 2000, 102:487-497.
43. Karlinsey JE, Tsui HC, Winkler ME, et al. Flk couples flgM translation to flagellar ring assembly in Salmonella typhimurium. Journal of Bacteriology, 1998, 180:5384-5397.
44. Keen NT, Boyd C, Henrissat B. Cloning and characterization of a xylanase gene from corn strains of Erwinia chrysanthemi. Molecular Plant-Microbe Interaction, 1996, 9(7):651-657.
45. Koplin R, Wang G, Hotte B, et al. A 3.9-kb DNA region of Xanthomonas campestris pv. campestris that is necessary for lipopolysaccharide production encodes a set of enzymes involved in the synthesis of dTDP-rhamnose. Journal of Bacteriology, 1993, 175:7786-7792.
46. Kuo TT, Lin BC, Li CC. Bacterial leaf blight of rice plant III. Phytotoxic polysaccharides produced by Xanthomonas oryzae. Botanical Bulletin of Academia Sinica, 1970, 11:46-54.
47. Kutsukake K, Ikebe T, Yamamoto S. Two novel regulatory genes, fliT and fliZ, in the flagellar regulon of Salmonella. Genes and Genetis Systems, 1999, 74:287-292.
48. Lee BM, Park YJ, Park DS, et al. The genome sequence of Xanthomonas oryzae pathovar oryzaeKACC10331, the bacterial blight pathogen of rice. Nucleic Acids Research, 2005, 33(2): 577-586.
49. Linda LM. Regulation of flagella. Current Opinion in Microbiology, 2006, 9:180-186.
50. Lindgren PB. The role of hrp genes during plant-bacterial interactions. Annual Review of Phytopathology, 1997, 35:129-152.
51. Lindgren PB, Peet RC, Panopoulos NJ. Gene cluster of Pseudomonas syringae pv. phaseolicola controls pathogenicity of bean plants and hypersensitivity on nonhost plants. Journal of Bacteriology, 1986, 168:512-522.
52. Liu X, Fujita N, Ishihama A, et al. The C-terminal region of the αsubunit of Escherichia coli RNA polymerase is required for transcriptional activation of the flagellar level Ⅱ operons by the FlhD/FlhC complex. Journal of Bacteriology, 1995, 177:5186-5188.
53. Liu X, Matsumura P. The FlhD/FlhC complex, a transcriptional activator of the Escherchia coli flagellar class Ⅱoperons. Journal of Bacteriology, 1994, 176:7345-7351.
54. Nandini Dasgupta, Matthew C. Wolfgang, et al. Goodman, et al. A four-tiered transcriptional regulatory circuit controls flagellar biogenesis in Pseudomonas aeruginosa. Molecular Microbiology, 2003, 50(3):809-824.
55. Noel L, Thieme F, Nennstiel D, et al. Two novel type III secreted proteins of Xanthomonas campestris pv. vesicatoria are encoded within the hrp pathogenicity island. Journal of Bacteriology, 2002, 184:1340-1348.
56. Olga AS, Philippe NB. Regulation cascsde of flagellar expression in Gram-negative bacteria. FEMS Microbiology Reviews, 2003, 27:505-523.
57. Ou SH. Rice diseases. Kew, Surrey: Commonwealth Agricultural Bureau. 1985
58. Phillip A, Kelly TH. Regullation of flagellar assembly. Current Opinion in Microbiology, 2002, 5:160-165
59. Pilippe N, Alcaraz JP, Coursange E, et al. Improvement of pCVD442, a suicide plasmid for gene allele exchange in bacteria. Plasmid, 2004, 52:246-255.
60. Poggio S, Osorio A, Dreyfus G, et al. The flagellar hierarchy of Rhodobacter sphaeroides is controlled by the concerted action of two enhancer-binding proteins. Molecular Microbiology, 2005, 58:969-983.
61. Rajeshwari R, Sonti RV. Stationary-phase variation due to transposition of novel insertion elements in Xanthomonas oryzae pv. oryzae. Journal of Bacteriology, 2000, 182:4797-4802.
62. Reitzer LJ, Magasanik B. Transcription of glnA in E.coli is stimulated by activator bound to sites far from the promoter. Cell, 1986, 45:785-792.
63. Ren CP, Beaston SA, Parkhill J, et al. The Flag-2 locus, an ancestral gene cluster, is potentially associated with a novel flagellar system from Escherichia coli. Journal of Bacteriology, 2005, 187:1430-1440
64. Richard CW, Paul W OT, Kieran AR. The FliK protein and flagellar hook-length control. Protein Science, 2007, 16:769-780.
65. Rossier O, Wengelnik K, Hahn K, et al. The Xanthomonas Hrp type III system secretes proteins from plant and mammalian bacterial pathogens. Proceedings of the National Academy of Sciences of the United States of Amercia, 1999, 96(16): 9368-9373.
66. Ryba-White M, Notteghem JL, Leach JE. Comparison of Xanthomonas oryzae pv. oryzae strains from Africa, North America and Asia by RFLP analysis. International Rice Research Notes, 1995, 20:25-26.
67. Salanoubat M, Genin S, Artiguenave F, et al. Genome sequence of the plant pathogen Ralstonia solanacearum. Nature, 2002, 415(6871): 497-502.
68. Sasaki T, Burr B. Interional Rice Genome Sequencing Project the effort to completely sequence the rice genome. Current Opinion in Plant Biology, 2000, 3:138-141.
69. Shen Y, Chern M, Silva F, et al. Isolation of a Xanthamonas oryzae pv. oryzae flagellar operon region and molecular characterization of flhF. Molecular Plant-Microbe Interaction, 2001, 14:204-213.
70. Simpson AJ, Reinach FC, Arruda F, et al. The xylella fastidiosa consortium of the organization for nucleotide sequencing and analysis. Nature, 2000, 406 (6792): 151-157.
71. Song WY, Wang GL, Chen L, et al. The rice disease resistance gene, Xa21, encodes a receptor-like protein kinase. Science, 1995, 270:1804-1806.
72. Soutourina OA, Semenova EA, Parfenova VV, et al. Control of bacterial motility by environmental factors in polarly flagellated and peritrichous bacteria isolated from Lake Baikal. Applied and Enviroment Microbiology, 2001, 67:3852-3859.
73. Spohn G, Scarlato V. Motility of Helicobacter pylori is coordindately regulated by the transcriptional activator FlgR, an NtrC homolog. Journal of Bacteriology, 1999, 181:593-599.
74. Steven LS, Daniel DS, Michael CS, et al. Genome sequence and rapid evolution of rice pathogen Xanthomonas oryzae pv. oryzae PXO99A. BioMed Central Genomics, 2008,9:204
75. Stock JB, Stock AM, Mottonen JM. Signal transduction in bacteria. Nature, 1990, 344:395-400.
76. Tang JL, Feng JX, Li QQ, et al. Cloning and characterization of the rplC gene of Xanthomonas oryzae pv. oryzae: involvement in exopolysaccharide production and virulence to rice. Molecular Plant-Microbe Interaction, 1996a, 9(7):664-666.
77. Thieme F, Koebnik R, Bekel T, et al. Insights into genome plasticity and pathogenicity of the plant pathogenic bacterium Xanthomonas campestris pv. vesicatoria revealed by the complete genome sequence. Journal of Bacteriology, 2005, 187(21): 7254-7266.
78. Torsten H, Ulla B. The rpoN gene of Xanthomonas campestris pv. vesicatoria is not required for pathogenicity. Molecular Plant-Microbe Interaction, 9(9): 856-859
79. Tsuchiya K, Mew TW, Wakimoto S. Bacteriological and pathological characteristics of wild types and induced mutants of Xanthomonas campestris pv. oryzae. Journal of Bacteriology, 1982, 72(1): 43-46.
80. Vidhyasekaran P, Alvenda ME, Mew TW. Physiological changes in rice seedlings induced byextracellular polysaccharide produced by Xanthomonas campestris pv. oryzae. Physiology, 1989, 35:391-402.
81. Vorholter FJ, Niehaus K, Puhler A. Lipopolysaccharide biosynthesis in Xanthomonas campestris pv. campestris: a cluster of 15 genes is involved in the biosynthesis of the LPS O-antigen and the LPS core. Molecular Genetics and Genomics, 2001, 266:79-95.
82. Whitfield C. Biosynthesis of lipopolysaccharide O-antigens. Trends Microbiol, 1995, 3:178-185.
83. Wood DW, Setubal J, Kaul R, et al. The genome of the natural genetic engineer Agrobacterium tumefaciens C58. Science, 2001, 294(5550): 2317-2323.
84. Wengelink K, Bonas U. HrpXv, an AraC-type regulator, activates expression of six loci in the hrp cluster of Xanthomonas campestris pv. vesicatoria essential for pathogenicity and induction of the hypersensitive reaction. Journal of Bacteriology, 1996, 178:3462-3469.
85. Yang B, Zhu WG, White F, 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. Proceedings of the National Academy of Science, 2000, 97:9807-9812.
86. Zhu W, Yang B, Wills N, et al. The C terminus of AvrXa21 can be replaced by the transcriptional activation domain of VP16 from the herpes simplex virus. Plant Cell, 1999, 11:1665-1674.
2. 赖世龙, 侯浩, 姜伟. 细菌的运动性及其在治病初期过程中的作用. 微生物学杂志, 2006, 26(5):68-70.
3. 李任峰, 何启盖, 周锐, 陈焕春.细菌鞭毛概况研究及进展. 微生物学通报, 2005, 32(6):124-127.
4. 章琦. 我国水稻白叶枯病抗性基因的利用及策略. 植物保护学报, 1995, 22(3):241-246
5. 朱友林. 水稻白叶枯病菌诱导水稻悬浮细胞防卫基因表达的初步研究.植物病理学报. 1997, 27:250.
6. Aldridge P, Hughes KT. How and when are substrates selected for type Ⅲ secretion. Trends in Microbiology, 2001, 9:209-214.
7. Alan JW, Karen LV. Get the message out: cyclic-di-GMP regulates multiple levels of flagellum-based motility. Journal of Bacteriology, 2008, 190(2): 463-475.
8. Amati G, Bisicchia P, Galizzi A. DegU-P represses expression of the motility fla-che operon in Bacillus subtilis. Journal of Bacteriology, 2004, 186:6003-6014.
9. Anderson PE, Gober JW. FlbT, the posr-transcriptional regulator of flagellin synthesis in Caulobacter crescentus, interacts with the 5′-untranslated region of flagellin mRNA. Molecular Microbiology, 2000, 38:41-52.
10. Andro T, Chambost JP, Kotoujansky A., et al. Mutants of Erwinia chrysanthemi defective in secretion of pectinase and cellulase. Journal of Bacteriology, 1984, 160(3):1199-1203.
11. Arora SK, Ritchings BW, Almira EC, et al. A transcriptional activator, FleQ, regulates mucin adhesion and flagellar gene expression in Pesudomonas aeruginosa in a cascade manner. Journal of Bacteriology, 1997, 179:5574-5581.
12. Auvray F, Thomas J, Fraser GM, et al. Flagellin polymerization control by a cytosolic export chaperone. Journal of Molecular Biology, 2001, 308:221-229.
13. Beier D, Frank R. Molecular characterization of two-component systems of Helicobacter pylori. Journal of Bacteriol, 2000, 182:2068-2076.
14. Bennet JC, Thomas J, Fraser GM, et al. Substrate complexes and domain organization of the Salmonella flagellar export chaperones FlgN and FliT. Molecular Microbiol, 2001, 39:781-791.
15. Bennet JC, Hughes C. From flagellum assembly to virulence: the extended family of type Ⅲ export chaperones. Trends in Microbiology, 2000, 8:202-204.
16. Buell CR., Joardar V., Lindeberg M., et al. The complete genome sequence of the Arabidopsis and tomato pathogen Pseudomonas syringae pv. tomato DC3000. Proceedings of National Academy of Sciences, 2003, 100:10181-10186.
17. Campos A, Matsumura P. Extensive alaine scanning reveals protein-protein and protein-DNA interaction surfaces in the global regulator FlhD from Escherichia coli. Molecular Microbiol, 2001,39: 581-594
18. Campos A, Zhang R, Alkire R, et al. Crystal structure of the global regulator FlhD from Escherichia coli at 1.8? resolution. Molecular Microbiol, 2001, 39:567-580.
19. Chilcott GS, Hughes KT. Coupling of flagellar gene expression to flagellar assembly in Salmonella enterica Serovar typhiumrium and Escherichia coli. Microbiol Molecular Biology Review, 2000, 64:694-708.
20. Claret L, Hughes C. Functions of the subunits in the FlhD2C2 transcriptional master regulator of bacterial flagellum bilgenesis and swarming. Journl of Molecular Biolology, 2000, 303:467-478.
21. Claret L, Hughes C. Interaction of the atypical prokaryotic transcription activator FlhD2C2 with early promoters of the flagellar gene hierarchy. Journl of Molecular Bilology, 2002, 321:185-199.
22. Correa NE, Peng F, Klose KE. Roles of the regulatory proteins FlhF and FlhG in the Vibrio cholerae flagellar transcription hierarchy. Journal of Bacteriology, 2005, 187:6324-6332.
23. Curtis L C. Deleterious effects of guttated fluid on foliage. American journal of bioethis, 1943, 30: 778–781
24. da Silva AC, Ferro JA, Reinach FC, et al. Comparison of the genomes of two Xanthomonas pathogens with differing host specificities. Nature, 2002, 417 (6887): 459-463.
25. da Silva FG, Shen Y, Dardick C, et al. Bacterial genes involved in type I secretion and sulfation are required to elicit the rice Xa21-mediated innate immune response. Moecularl Plant-Microbe Interaction, 2004, 17:593-601
26. Darwin KH, Miller VL. Type Ⅲ secretion chaperone-dependent regulation: activation of virulence genes by SicA and InvF in Salmonella typhimurium. The EMBO Journal, 2001, 20:1850-1862.
27. Dasgupta N, Ramphal R. Interaction of the antiactivator FleN with the transcriptional activator FleQ regulates flagellar number in Pseudomonas aeruginosa. Journal of Bacteriology, 2001, 183:6636-6644.
28. David O, Ronald PC, Bogdanove AJ, et al. Xanthomonas oryzae pathovars: model pathogens of a model crop. Molecular Plant Pathology, 2006, 7(5): 303-324.
29. Dow JM, Osbourn AE, Wilson TJ, et al. A locus determining pathogenicity of Xanthomonas campestris is involved in lipopolysaccharide biosynthesis. Molecular Plant-Microbe Interaction, 1995, 8:768-777.
30. Dutton RJ, Xu Z, Gober JW. Linking structural assembly to gene expression: a novel mechanism for regulating the activity of a sigma transcription factor. Molecular Microbiology, 2005, 58:743-757.
31. England JC, Gober JW. Cell cycle control of cell morphogenesis in Caulobacter. Current Opinion in Microbiol, 2001, 4: 674-680
32. Ezuka A, Kaku H. A historical review of bacterial blight of rice. Plant Molecular Biology, 2000, 15:53-54.
33. Fenselau S, Bonas U. Sequence and expression analysis of the hrpB pathogenicity operon of Xanthomonas campestris pv. vesicatoria which encodes eight proteins with similarity to components of the Hrp, Ysc, Spa, and Fli secretion systems. Molecular Plant-Microbe Interaction, 1995, 8: 845-854.
34. Francis MS, Lloyd SA, Wolf-Watz H. The type Ⅲ secretion chaperone LcrH co-operates with YopD to establish a negative, regulatory loop for control of Yop synthesis in Yersinis psuedotuberculosis. Molecular Microbiology, 2001, 42:1075-1093.
35. Fraser GM, Bennett JC, Hughes C. Substrate-specific binding of hook-associated proteins by FlgN and FliT, putative chaperones for flagellum assembly. Molecular Microbiology, 1999, 32:569-580.
36. Gu KY, Yang B, Tian D, et al. R gene expression induced by a type-III effector triggers disease resistance in rice. Nature, 2005, 435:1122-1125.
37. He SY. Type III protein secretion systems in plant and animal pathogenic bacteria. Annual Review of Phytopathology, 1998, 36:363-392.
38. Hirokazu O, Yasuhiro I, Masaru T. Genome sequence of Xanthomonas oryzae pv. oryzae suggests contribution of large numbers of effector genes and insertion sequences to its race diversity. Japan Agricultural Research Quarterly, 2005, 39(4): 275-287.
39. Hopkins CM, White FF, Choi SH, et al. Identification of a family of avirulence genes from Xanthomonas oryzae pv. oryzae. Molecular Plant-Microbe Interaction, 1992, 5(6): 451-459.
40. Hu RM, Yang TC, Yang SH, et al. Deduction of upstream sequences of Xanthomonas campestris flagellar genes responding to transcription activation by FleQ. Biochemical and Biophysical Research Communication. 2005, 335: 1035-1043.
41. Iyer AS, McCouch SR. The rice bacterial blight resistance gene xa5 encodes a novel form of disease resistance. Molecular Plant-Microbe Interaction, 2004, 17:1348-1354.
42. Karlinsey JE, Lonner J, Brown KL, et al. Translation/secretion coupling by type Ⅲ secretion systems. Cell, 2000, 102:487-497.
43. Karlinsey JE, Tsui HC, Winkler ME, et al. Flk couples flgM translation to flagellar ring assembly in Salmonella typhimurium. Journal of Bacteriology, 1998, 180:5384-5397.
44. Keen NT, Boyd C, Henrissat B. Cloning and characterization of a xylanase gene from corn strains of Erwinia chrysanthemi. Molecular Plant-Microbe Interaction, 1996, 9(7):651-657.
45. Koplin R, Wang G, Hotte B, et al. A 3.9-kb DNA region of Xanthomonas campestris pv. campestris that is necessary for lipopolysaccharide production encodes a set of enzymes involved in the synthesis of dTDP-rhamnose. Journal of Bacteriology, 1993, 175:7786-7792.
46. Kuo TT, Lin BC, Li CC. Bacterial leaf blight of rice plant III. Phytotoxic polysaccharides produced by Xanthomonas oryzae. Botanical Bulletin of Academia Sinica, 1970, 11:46-54.
47. Kutsukake K, Ikebe T, Yamamoto S. Two novel regulatory genes, fliT and fliZ, in the flagellar regulon of Salmonella. Genes and Genetis Systems, 1999, 74:287-292.
48. Lee BM, Park YJ, Park DS, et al. The genome sequence of Xanthomonas oryzae pathovar oryzaeKACC10331, the bacterial blight pathogen of rice. Nucleic Acids Research, 2005, 33(2): 577-586.
49. Linda LM. Regulation of flagella. Current Opinion in Microbiology, 2006, 9:180-186.
50. Lindgren PB. The role of hrp genes during plant-bacterial interactions. Annual Review of Phytopathology, 1997, 35:129-152.
51. Lindgren PB, Peet RC, Panopoulos NJ. Gene cluster of Pseudomonas syringae pv. phaseolicola controls pathogenicity of bean plants and hypersensitivity on nonhost plants. Journal of Bacteriology, 1986, 168:512-522.
52. Liu X, Fujita N, Ishihama A, et al. The C-terminal region of the αsubunit of Escherichia coli RNA polymerase is required for transcriptional activation of the flagellar level Ⅱ operons by the FlhD/FlhC complex. Journal of Bacteriology, 1995, 177:5186-5188.
53. Liu X, Matsumura P. The FlhD/FlhC complex, a transcriptional activator of the Escherchia coli flagellar class Ⅱoperons. Journal of Bacteriology, 1994, 176:7345-7351.
54. Nandini Dasgupta, Matthew C. Wolfgang, et al. Goodman, et al. A four-tiered transcriptional regulatory circuit controls flagellar biogenesis in Pseudomonas aeruginosa. Molecular Microbiology, 2003, 50(3):809-824.
55. Noel L, Thieme F, Nennstiel D, et al. Two novel type III secreted proteins of Xanthomonas campestris pv. vesicatoria are encoded within the hrp pathogenicity island. Journal of Bacteriology, 2002, 184:1340-1348.
56. Olga AS, Philippe NB. Regulation cascsde of flagellar expression in Gram-negative bacteria. FEMS Microbiology Reviews, 2003, 27:505-523.
57. Ou SH. Rice diseases. Kew, Surrey: Commonwealth Agricultural Bureau. 1985
58. Phillip A, Kelly TH. Regullation of flagellar assembly. Current Opinion in Microbiology, 2002, 5:160-165
59. Pilippe N, Alcaraz JP, Coursange E, et al. Improvement of pCVD442, a suicide plasmid for gene allele exchange in bacteria. Plasmid, 2004, 52:246-255.
60. Poggio S, Osorio A, Dreyfus G, et al. The flagellar hierarchy of Rhodobacter sphaeroides is controlled by the concerted action of two enhancer-binding proteins. Molecular Microbiology, 2005, 58:969-983.
61. Rajeshwari R, Sonti RV. Stationary-phase variation due to transposition of novel insertion elements in Xanthomonas oryzae pv. oryzae. Journal of Bacteriology, 2000, 182:4797-4802.
62. Reitzer LJ, Magasanik B. Transcription of glnA in E.coli is stimulated by activator bound to sites far from the promoter. Cell, 1986, 45:785-792.
63. Ren CP, Beaston SA, Parkhill J, et al. The Flag-2 locus, an ancestral gene cluster, is potentially associated with a novel flagellar system from Escherichia coli. Journal of Bacteriology, 2005, 187:1430-1440
64. Richard CW, Paul W OT, Kieran AR. The FliK protein and flagellar hook-length control. Protein Science, 2007, 16:769-780.
65. Rossier O, Wengelnik K, Hahn K, et al. The Xanthomonas Hrp type III system secretes proteins from plant and mammalian bacterial pathogens. Proceedings of the National Academy of Sciences of the United States of Amercia, 1999, 96(16): 9368-9373.
66. Ryba-White M, Notteghem JL, Leach JE. Comparison of Xanthomonas oryzae pv. oryzae strains from Africa, North America and Asia by RFLP analysis. International Rice Research Notes, 1995, 20:25-26.
67. Salanoubat M, Genin S, Artiguenave F, et al. Genome sequence of the plant pathogen Ralstonia solanacearum. Nature, 2002, 415(6871): 497-502.
68. Sasaki T, Burr B. Interional Rice Genome Sequencing Project the effort to completely sequence the rice genome. Current Opinion in Plant Biology, 2000, 3:138-141.
69. Shen Y, Chern M, Silva F, et al. Isolation of a Xanthamonas oryzae pv. oryzae flagellar operon region and molecular characterization of flhF. Molecular Plant-Microbe Interaction, 2001, 14:204-213.
70. Simpson AJ, Reinach FC, Arruda F, et al. The xylella fastidiosa consortium of the organization for nucleotide sequencing and analysis. Nature, 2000, 406 (6792): 151-157.
71. Song WY, Wang GL, Chen L, et al. The rice disease resistance gene, Xa21, encodes a receptor-like protein kinase. Science, 1995, 270:1804-1806.
72. Soutourina OA, Semenova EA, Parfenova VV, et al. Control of bacterial motility by environmental factors in polarly flagellated and peritrichous bacteria isolated from Lake Baikal. Applied and Enviroment Microbiology, 2001, 67:3852-3859.
73. Spohn G, Scarlato V. Motility of Helicobacter pylori is coordindately regulated by the transcriptional activator FlgR, an NtrC homolog. Journal of Bacteriology, 1999, 181:593-599.
74. Steven LS, Daniel DS, Michael CS, et al. Genome sequence and rapid evolution of rice pathogen Xanthomonas oryzae pv. oryzae PXO99A. BioMed Central Genomics, 2008,9:204
75. Stock JB, Stock AM, Mottonen JM. Signal transduction in bacteria. Nature, 1990, 344:395-400.
76. Tang JL, Feng JX, Li QQ, et al. Cloning and characterization of the rplC gene of Xanthomonas oryzae pv. oryzae: involvement in exopolysaccharide production and virulence to rice. Molecular Plant-Microbe Interaction, 1996a, 9(7):664-666.
77. Thieme F, Koebnik R, Bekel T, et al. Insights into genome plasticity and pathogenicity of the plant pathogenic bacterium Xanthomonas campestris pv. vesicatoria revealed by the complete genome sequence. Journal of Bacteriology, 2005, 187(21): 7254-7266.
78. Torsten H, Ulla B. The rpoN gene of Xanthomonas campestris pv. vesicatoria is not required for pathogenicity. Molecular Plant-Microbe Interaction, 9(9): 856-859
79. Tsuchiya K, Mew TW, Wakimoto S. Bacteriological and pathological characteristics of wild types and induced mutants of Xanthomonas campestris pv. oryzae. Journal of Bacteriology, 1982, 72(1): 43-46.
80. Vidhyasekaran P, Alvenda ME, Mew TW. Physiological changes in rice seedlings induced byextracellular polysaccharide produced by Xanthomonas campestris pv. oryzae. Physiology, 1989, 35:391-402.
81. Vorholter FJ, Niehaus K, Puhler A. Lipopolysaccharide biosynthesis in Xanthomonas campestris pv. campestris: a cluster of 15 genes is involved in the biosynthesis of the LPS O-antigen and the LPS core. Molecular Genetics and Genomics, 2001, 266:79-95.
82. Whitfield C. Biosynthesis of lipopolysaccharide O-antigens. Trends Microbiol, 1995, 3:178-185.
83. Wood DW, Setubal J, Kaul R, et al. The genome of the natural genetic engineer Agrobacterium tumefaciens C58. Science, 2001, 294(5550): 2317-2323.
84. Wengelink K, Bonas U. HrpXv, an AraC-type regulator, activates expression of six loci in the hrp cluster of Xanthomonas campestris pv. vesicatoria essential for pathogenicity and induction of the hypersensitive reaction. Journal of Bacteriology, 1996, 178:3462-3469.
85. Yang B, Zhu WG, White F, 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. Proceedings of the National Academy of Science, 2000, 97:9807-9812.
86. Zhu W, Yang B, Wills N, et al. The C terminus of AvrXa21 can be replaced by the transcriptional activation domain of VP16 from the herpes simplex virus. Plant Cell, 1999, 11:1665-1674.