Characterization, Phylogeny, and Genome Analyses of Nonpathogenic Xanthomonas campestris Strains Isolated from Brassica Seeds

Xanthomonads were detected by using the Xan-D(CCF) medium from the brassica seeds, and their pathogenicity was determined by plant inoculation tests. It was found that some seed lots were infested with Xanthomonas campestris pv. campestris, some with X. campestris pv. raphani, and some with nonpathogenic xanthomonads. The nonpathogenic xanthomonad strains were identified as X. campestris, and the multilocus sequence analysis showed that the nonpathogenic X. campestris strains were grouped together with pathogenic X. campestris, but not with nonpathogenic strains of X. arboricola. In addition, all isolated X. campestris pv. campestris and X. campestris pv. raphani strains were positive in the hrpF-PCR, but the nonpathogenic strains were negative. It was further found that nonpathogenic X. campestris strain nE1 does not contain the entire pathogenicity island (hrp gene cluster; type III secretion system) and all type III effector protein genes based on the whole genome sequence analyses. The nonpathogenic X. campestris strain nE1 could acquire the entire pathogenicity island from the endemic X. campestris pv. campestris and X. campestris pv. raphani strains by conjugation, but type III effector genes were not cotransferred. The studies showed that the nonpathogenic X. campestris strains indeed exist on the brassica seeds, but it could be differentiated by the PCR assays on the hrp and type III effector genes. Nevertheless, the nonpathogenic X. campestris strains cannot be ignored because they may be potential gene resources to increase genetic diversity in the endemic pathogenic X. campestris pv. campestris and X. campestris pv. raphani strains.

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Distribution of espI among clinical enterohaemorrhagic and enteropathogenic Escherichia coli isolates

Journal of Medical Microbiology ◽

10.1099/jmm.0.45684-0 ◽

2004 ◽

Vol 53 (11) ◽

pp. 1145-1149 ◽

Cited By ~ 29

Author(s):

Rosanna Mundy ◽

Claire Jenkins ◽

Jun Yu ◽

Henry Smith ◽

Gad Frankel

Keyword(s):

Escherichia Coli ◽

Type Iii Secretion ◽

Severe Disease ◽

Pathogenicity Island ◽

Effector Proteins ◽

Effector Protein ◽

Enteropathogenic Escherichia Coli ◽

Type Iii Effector ◽

Type Iii

Enterohaemorrhagic (EHEC) and enteropathogenic (EPEC) Escherichia coli are important diarrhoeagenic pathogens; infection is dependent on translocation of a number of type III effector proteins. Until recently all the known effectors were encoded on the LEE pathogenicity island, which also encodes the adhesin intimin and the type III secretion apparatus. Recently, a novel non-LEE effector protein, EspI/NleA, which is required for full virulence in vivo and is encoded on a prophage, was identified. The aim of this study was to determine the distribution of espI among clinical EHEC and EPEC isolates. espI was detected in 86 % and 53 % of LEE+ EHEC and EPEC strains, respectively. Moreover, the espI gene was more commonly found in patients suffering from a more severe disease.

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Identification of a novel type III secretion-associated outer membrane-bound protein from Xanthomonas campestris pv. campestris

Scientific Reports ◽

10.1038/srep42724 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 6

Author(s):

Lei Li ◽

Rui-Fang Li ◽

Zhen-Hua Ming ◽

Guang-Tao Lu ◽

Ji-Liang Tang

Keyword(s):

Outer Membrane ◽

Type Iii Secretion ◽

Xanthomonas Campestris ◽

Type Iii ◽

Membrane Bound ◽

Xanthomonas Campestris Pv Campestris

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Characterization of the Xanthomonas axonopodis pv. glycines Hrp Pathogenicity Island

Journal of Bacteriology ◽

10.1128/jb.185.10.3155-3166.2003 ◽

2003 ◽

Vol 185 (10) ◽

pp. 3155-3166 ◽

Cited By ~ 94

Author(s):

Jung-Gun Kim ◽

Byoung Keun Park ◽

Chang-Hyuk Yoo ◽

Eunkyung Jeon ◽

Jonghee Oh ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Type Iii Secretion ◽

Pathogenicity Island ◽

Inducible Promoter ◽

Core Region ◽

Effector Protein ◽

Trna Genes ◽

Secretion Systems ◽

Xanthomonas Axonopodis ◽

Type Iii

ABSTRACT We sequenced an approximately 29-kb region from Xanthomonas axonopodis pv. glycines that contained the Hrp type III secretion system, and we characterized the genes in this region by Tn3-gus mutagenesis and gene expression analyses. From the region, hrp (hypersensitive response and pathogenicity) and hrc (hrp and conserved) genes, which encode type III secretion systems, and hpa (hrp-associated) genes were identified. The characteristics of the region, such as the presence of many virulence genes, low G+C content, and bordering tRNA genes, satisfied the criteria for a pathogenicity island (PAI) in a bacterium. The PAI was composed of nine hrp, nine hrc, and eight hpa genes with seven plant-inducible promoter boxes. The hrp and hrc mutants failed to elicit hypersensitive responses in pepper plants but induced hypersensitive responses in all tomato plants tested. The Hrp PAI of X. axonopodis pv. glycines resembled the Hrp PAIs of other Xanthomonas species, and the Hrp PAI core region was highly conserved. However, in contrast to the PAI of Pseudomonas syringae, the regions upstream and downstream from the Hrp PAI core region showed variability in the xanthomonads. In addition, we demonstrate that HpaG, which is located in the Hrp PAI region of X. axonopodis pv. glycines, is a response elicitor. Purified HpaG elicited hypersensitive responses at a concentration of 1.0 μM in pepper, tobacco, and Arabidopsis thaliana ecotype Cvi-0 by acting as a type III secreted effector protein. However, HpaG failed to elicit hypersensitive responses in tomato, Chinese cabbage, and A. thaliana ecotypes Col-0 and Ler. This is the first report to show that the harpin-like effector protein of Xanthomonas species exhibits elicitor activity.

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VopF, a type III effector protein from a non-O1, non-O139 Vibrio cholerae strain, demonstrates toxicity in a Saccharomyces cerevisiae model

Journal of Medical Microbiology ◽

10.1099/jmm.0.012336-0 ◽

2010 ◽

Vol 59 (1) ◽

pp. 17-24 ◽

Cited By ~ 8

Author(s):

Ranjana Tripathi ◽

Santa Singh Naorem ◽

Chetna Dureja ◽

Swati Haldar ◽

Alok K. Mondal ◽

...

Keyword(s):

Vibrio Cholerae ◽

Type Iii Secretion ◽

Ectopic Expression ◽

Contributory Factor ◽

Cholerae Strain ◽

Effector Protein ◽

Intestinal Colonization ◽

Type Iii Effector ◽

Type Iii ◽

Insight Into

VopF, a type III effector protein, has been identified as a contributory factor to the intestinal colonization of type III secretion system-positive, non-O1, non-O139 Vibrio cholerae strains. To gain more insight into the function of VopF, a yeast model was developed. Using this model, it was found that ectopic expression of VopF conferred toxicity in yeast.

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The Shiga Toxin 1-Converting Bacteriophage BP-4795 Encodes an NleA-Like Type III Effector Protein

Journal of Bacteriology ◽

10.1128/jb.187.24.8494-8498.2005 ◽

2005 ◽

Vol 187 (24) ◽

pp. 8494-8498 ◽

Cited By ~ 32

Author(s):

Kristina Creuzburg ◽

Jürgen Recktenwald ◽

Volker Kuhle ◽

Sylvia Herold ◽

Michael Hensel ◽

...

Keyword(s):

Shiga Toxin ◽

Type Iii Secretion ◽

Regulatory Region ◽

Secretion System ◽

Open Reading Frames ◽

Effector Protein ◽

Type Iii Effector ◽

Type Iii ◽

Enterocyte Effacement ◽

Reading Frames

ABSTRACT In this study, the complete DNA sequence of Shiga toxin 1-converting bacteriophage BP-4795 was determined. The genome of BP-4795 consists of 85 open reading frames, including two complete IS629 elements and three morons at the end of its late regulatory region. One of these morons encodes a type III effector that is translocated by the locus of enterocyte effacement-encoded type III secretion system into HeLa cells, where it localizes with the Golgi apparatus.

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Identification of Six Type III Effector Genes with the PIP Box in Xanthomonas campestris pv. campestris and Five of Them Contribute Individually to Full Pathogenicity

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-22-11-1401 ◽

2009 ◽

Vol 22 (11) ◽

pp. 1401-1411 ◽

Cited By ~ 43

Author(s):

Wei Jiang ◽

Bo-Le Jiang ◽

Rong-Qi Xu ◽

Jun-Ding Huang ◽

Hong-Yu Wei ◽

...

Keyword(s):

Xanthomonas Campestris ◽

Regulatory Element ◽

Regulatory Protein ◽

Plant Cells ◽

Dependent Manner ◽

Type Iii ◽

Effector Genes ◽

A Genome ◽

Hrp Genes ◽

Xanthomonas Campestris Pv Campestris

Xanthomonas campestris pv. campestris is the pathogen of black rot of cruciferous plants. The pathogenicity of the pathogen depends on the type III secretion system (T3SS) that translocates directly effector proteins into plant cells, where they play important roles in the molecular interaction between the pathogen and its hosts. The T3SS of Xanthomonas spp. is encoded by a cluster of hypersensitive response and pathogenicity (hrp) genes. It has been demonstrated that the expression of hrp genes and some type III secreted (T3S)-effector genes is coactivated by the key hrp regulatory protein HrpX. The regulation by HrpX can be mediated by the binding of HrpX protein to a cis-regulatory element named the plant-inducible promoter (PIP) box present in the promoter region of HrpX-regulated genes. A genome screen revealed that X. campestris pv. campestris 8004 possesses 56 predicted genes with the PIP box. Nine of these genes have been shown to encode T3S effectors, Hrp, and Hrp-associated proteins. In this study, we employed an established T3S effector translocation assay with the hypersensitive-reaction-inducing domain of X. campestris pv. campestris AvrBs1 as a reporter to characterize the remaining 47 genes with the PIP box and showed that 6 of them, designated as XopXccE1, XopXccP, XopXccQ, XopXccR1, XopXccLR, and AvrXccB, harbor a functional translocation signal in their N-terminal regions, indicating that they are T3S effectors of X. campestris pv. campestris. We provided evidence to demonstrate that all these effectors are expressed in an HrpX-dependent manner and their translocation into plant cells relies on the translocon protein HrpF and the chaperone HpaB. Mutational analyses demonstrated that all these effectors, except AvrXccB, are individually required for full virulence and growth of X. campestris pv. campestris in the host plant Chinese radish.

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Role of the Salmonella Pathogenicity Island 1 (SPI-1) Protein InvB in Type III Secretion of SopE and SopE2, Two Salmonella Effector Proteins Encoded Outside of SPI-1

Journal of Bacteriology ◽

10.1128/jb.185.23.6950-6967.2003 ◽

2003 ◽

Vol 185 (23) ◽

pp. 6950-6967 ◽

Cited By ~ 62

Author(s):

Kristin Ehrbar ◽

Andrea Friebel ◽

Samuel I. Miller ◽

Wolf-Dietrich Hardt

Keyword(s):

Type Iii Secretion ◽

Inflammatory Responses ◽

Pathogenicity Island ◽

Effector Proteins ◽

Host Cells ◽

Effector Protein ◽

Dependent Manner ◽

Type Iii ◽

Serovar Typhimurium

ABSTRACT Salmonella enterica subspecies 1 serovar Typhimurium encodes a type III secretion system (TTSS) within Salmonella pathogenicity island 1 (SPI-1). This TTSS injects effector proteins into host cells to trigger invasion and inflammatory responses. Effector proteins are recognized by the TTSS via signals encoded in their N termini. Specific chaperones can be involved in this process. The chaperones InvB, SicA, and SicP are encoded in SPI-1 and are required for transport of SPI-1-encoded effectors. Several key effector proteins, like SopE and SopE2, are located outside of SPI-1 but are secreted in an SPI-1-dependent manner. It has not been clear how these effector proteins are recognized by the SPI-1 TTSS. Using pull-down and coimmunoprecipitation assays, we found that SopE is copurified with InvB, the known chaperone for the SPI-1-encoded effector protein Sip/SspA. We also found that InvB is required for secretion and translocation of SopE and SopE2 and for stabilization of SopE2 in the bacterial cytosol. Our data demonstrate that effector proteins encoded within and outside of SPI-1 use the same chaperone for secretion via the SPI-1 TTSS.

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