1
|
Khanh NV, Lee YH. LOV1 protein of Pseudomonas cichorii JBC1 modulates its virulence and lifestyles in response to blue light. Sci Rep 2024; 14:15672. [PMID: 38977737 PMCID: PMC11231323 DOI: 10.1038/s41598-024-66422-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Accepted: 07/01/2024] [Indexed: 07/10/2024] Open
Abstract
Bacteria perceive light signals via photoreceptors and modulate many physiological and genetic processes. The impacts played by light, oxygen, or voltage (LOV) and blue light (BL) photosensory proteins on the virulence-related traits of plant bacterial pathogens are diverse and complex. In this study, we identified LOV protein (Pc-LOV1) from Pseudomonas cichorii JBC1 (PcJBC1) and characterized its function using LOV1-deficient mutant (JBC1Δlov1). In the dark state, the recombinant Pc-LOV1 protein showed an absorption band in UV-A region with a double peak at 340 nm and 365 nm, and within the blue-region, it exhibited a main absorption at 448 nm along with two shoulder peaks at 425 nm and 475 nm, which is a typical feature of oxidized flavin within LOV domain. The adduct-state lifetime (τrec) of Pc-LOV1 was 67.03 ± 4.34 min at 25 °C. BL negatively influenced the virulence of PcJBC1 and the virulence of JBC1Δlov1 increased irrespective of BL, indicating that Pc-LOV1 negatively regulates PcJBC1 virulence. Pc-LOV1 and BL positively regulated traits relevant to colonization on plant surface, such as adhesion to the plant tissue and biofilm formation. In contrast, swarming motility, exopolysaccharide production, and siderophore synthesis were negatively controlled. Gene expression supported the modulation of bacterial features by Pc-LOV1. Overall, our results suggest that the LOV photosensory system plays crucial roles in the adaptive responses and virulence of the bacterial pathogen PcJBC1. The roles of other photoreceptors, sensing of other wavelengths, and signal networking require further investigation.
Collapse
Affiliation(s)
- Nguyen Van Khanh
- Division of Biotechnology, Jeonbuk National University, 79 Gobong-ro, Iksan-si, Jeollabuk-do, 54596, Republic of Korea
| | - Yong Hoon Lee
- Division of Biotechnology, Jeonbuk National University, 79 Gobong-ro, Iksan-si, Jeollabuk-do, 54596, Republic of Korea.
- Advanced Institute of Environment and Bioscience, Plant Medical Research Center, and Institute of Bio-industry, Jeonbuk National University, Jeonju-si, Republic of Korea.
| |
Collapse
|
2
|
Arasakumar N, Loganathan V, Natesh R, Ponnuraj K. HrpY protein of Ralstonia solanacearum exhibits spontaneous formation of pilus like assembly: analysis of its stability. J Biomol Struct Dyn 2024:1-12. [PMID: 38230438 DOI: 10.1080/07391102.2024.2304678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 01/04/2024] [Indexed: 01/18/2024]
Abstract
Type 3 secretory system (T3SS), a complex protein machinery has a unique virulence mechanism that involves injecting effector proteins directly into host cells. The T3SS effector proteins are transported through an extracellular long hollow needle made up of multiple copies of a small protein. In T3SS of the plant pathogen Ralstonia solanacearum, the 8.6 kDa HrpY protein assembles into a large needle like apparatus (pilus) for transporting effector proteins. To study structural details of HrpY, we recombinantly expressed and purified HrpY in E. coli. The dynamic light scattering (DLS) analysis showed that rHrpY has spontaneously formed oligomers of large order (>100 nm). Transmission electron microscopy of rHrpY samples revealed that the large structures are tube like assembly having dimensions 86.3-166.6 nm and 5.8-6.8 nm in length and width respectively. Different molecular sizes of the purified rHrpY hindered the crystallization of the protein. The stability of oligomer assembly was studied with denaturants and surfactants. Denaturants like urea and guanidine HCl could not break them apart; however, detergents like SDS, sarkosyl, Octyl-β-Glucoside, CHAPS, Tween 20, Tween 80 and Triton X-100 showed disassembly of the oligomer. rHrpY assembly was found to withstand up to 50 °C and the circular dichroism analysis revealed that there is no significant change in the secondary structural composition with increase in temperature. However, change in the secondary structure was observed with the addition of SDS.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Naveen Arasakumar
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Chennai, India
| | - Vikraam Loganathan
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Chennai, India
| | - Ramanathan Natesh
- Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM), Vithura, Trivandrum, India
| | - Karthe Ponnuraj
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Chennai, India
| |
Collapse
|
3
|
Linalool reduces the virulence of Pseudomonas syringae pv. tomato DC 3000 by modulating the PsyI/PsyR quorum-sensing system. Microb Pathog 2022; 173:105884. [DOI: 10.1016/j.micpath.2022.105884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/09/2022] [Accepted: 11/11/2022] [Indexed: 11/15/2022]
|
4
|
Huang CL, Pu PH, Huang HJ, Sung HM, Liaw HJ, Chen YM, Chen CM, Huang MB, Osada N, Gojobori T, Pai TW, Chen YT, Hwang CC, Chiang TY. Ecological genomics in Xanthomonas: the nature of genetic adaptation with homologous recombination and host shifts. BMC Genomics 2015; 16:188. [PMID: 25879893 PMCID: PMC4372319 DOI: 10.1186/s12864-015-1369-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 02/20/2015] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Comparative genomics provides insights into the diversification of bacterial species. Bacterial speciation usually takes place with lasting homologous recombination, which not only acts as a cohering force between diverging lineages but brings advantageous alleles favored by natural selection, and results in ecologically distinct species, e.g., frequent host shift in Xanthomonas pathogenic to various plants. RESULTS Using whole-genome sequences, we examined the genetic divergence in Xanthomonas campestris that infected Brassicaceae, and X. citri, pathogenic to a wider host range. Genetic differentiation between two incipient races of X. citri pv. mangiferaeindicae was attributable to a DNA fragment introduced by phages. In contrast to most portions of the genome that had nearly equivalent levels of genetic divergence between subspecies as a result of the accumulation of point mutations, 10% of the core genome involving with homologous recombination contributed to the diversification in Xanthomonas, as revealed by the correlation between homologous recombination and genomic divergence. Interestingly, 179 genes were under positive selection; 98 (54.7%) of these genes were involved in homologous recombination, indicating that foreign genetic fragments may have caused the adaptive diversification, especially in lineages with nutritional transitions. Homologous recombination may have provided genetic materials for the natural selection, and host shifts likely triggered ecological adaptation in Xanthomonas. To a certain extent, we observed positive selection nevertheless contributed to ecological divergence beyond host shifting. CONCLUSION Altogether, mediated with lasting gene flow, species formation in Xanthomonas was likely governed by natural selection that played a key role in helping the deviating populations to explore novel niches (hosts) or respond to environmental cues, subsequently triggering species diversification.
Collapse
Affiliation(s)
- Chao-Li Huang
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Pei-Hua Pu
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Hao-Jen Huang
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Huang-Mo Sung
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Hung-Jiun Liaw
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Yi-Min Chen
- Institute of Biotechnology, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Chien-Ming Chen
- Department of Computer Science and Engineering, National Taiwan Ocean University, Keelung, 202, Taiwan.
| | - Ming-Ban Huang
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Naoki Osada
- National Institute of Genetics, Mishima, Shizuoka, 411-8540, Yata, Japan.
| | - Takashi Gojobori
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
- National Institute of Genetics, Mishima, Shizuoka, 411-8540, Yata, Japan.
- Computational Bioscience Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia.
| | - Tun-Wen Pai
- Department of Computer Science and Engineering, National Taiwan Ocean University, Keelung, 202, Taiwan.
| | - Yu-Tin Chen
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Chi-Chuan Hwang
- Department of Engineering Science and Supercomputing Research Center, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Tzen-Yuh Chiang
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| |
Collapse
|
5
|
Tampakaki AP. Commonalities and differences of T3SSs in rhizobia and plant pathogenic bacteria. FRONTIERS IN PLANT SCIENCE 2014; 5:114. [PMID: 24723933 PMCID: PMC3973906 DOI: 10.3389/fpls.2014.00114] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 03/11/2014] [Indexed: 05/19/2023]
Abstract
Plant pathogenic bacteria and rhizobia infect higher plants albeit the interactions with their hosts are principally distinct and lead to completely different phenotypic outcomes, either pathogenic or mutualistic, respectively. Bacterial protein delivery to plant host plays an essential role in determining the phenotypic outcome of plant-bacteria interactions. The involvement of type III secretion systems (T3SSs) in mediating animal- and plant-pathogen interactions was discovered in the mid-80's and is now recognized as a multiprotein nanomachine dedicated to trans-kingdom movement of effector proteins. The discovery of T3SS in bacteria with symbiotic lifestyles broadened its role beyond virulence. In most T3SS-positive bacterial pathogens, virulence is largely dependent on functional T3SSs, while in rhizobia the system is dispensable for nodulation and can affect positively or negatively the mutualistic associations with their hosts. This review focuses on recent comparative genome analyses in plant pathogens and rhizobia that uncovered similarities and variations among T3SSs in their genetic organization, regulatory networks and type III secreted proteins and discusses the evolutionary adaptations of T3SSs and type III secreted proteins that might account for the distinguishable phenotypes and host range characteristics of plant pathogens and symbionts.
Collapse
Affiliation(s)
- Anastasia P. Tampakaki
- *Correspondence: Anastasia P. Tampakaki, Laboratory of General and Agricultural Microbiology, Department of Crop Science, Agricultural University of Athens, Iera Odos 75, Votanikos, 11855, Athens, Greece e-mail:
| |
Collapse
|
6
|
De-La-Peña C, Rangel-Cano A, Alvarez-Venegas R. Regulation of disease-responsive genes mediated by epigenetic factors: interaction of Arabidopsis-Pseudomonas. MOLECULAR PLANT PATHOLOGY 2012; 13:388-98. [PMID: 22023111 PMCID: PMC6638851 DOI: 10.1111/j.1364-3703.2011.00757.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Genes in eukaryotic organisms function within the context of chromatin, and the mechanisms that modulate the structure of chromatin are defined as epigenetic. In Arabidopsis, pathogen infection induces the expression of at least one histone deacetylase, suggesting that histone acetylation/deacetylation has an important role in the pathogenic response in plants. How/whether histone methylation affects gene response to pathogen infection is unknown. To gain a better understanding of the epigenetic mechanisms regulating the interaction between Pseudomonas syringae and Arabidopsis thaliana, we analysed three different Arabidopsis ash1-related (absent, small or homeotic discs 1) mutants. We found that the loss of function of ASHH2 and ASHR1 resulted in faster hypersensitive responses (HRs) to both mutant (hrpA) and pathogenic (DC3000) strains of P. syringae, whereas control (Col-0) and ashr3 mutants appeared to be more resistant to the infection after 2 days. Furthermore, we showed that, in the ashr3 background, the PR1 gene (PATHOGENESIS-RELATED GENE 1) displayed the highest expression levels on infection with DC3000, correlating with increased resistance against this pathogen. Our results show that, in both the ashr1 and ashh2 backgrounds, the histone H3 lysine 4 dimethylation (H3K4me2) levels decreased at the promoter region of PR1 on infection with the DC3000 strain, suggesting that an epigenetically regulated PR1 expression is involved in the plant defence. Our results suggest that histone methylation in response to pathogen infection may be a critical component in the signalling and defence processes occurring between plants and microbes.
Collapse
Affiliation(s)
- Clelia De-La-Peña
- Department of Genetic Engineering, Centro de Investigación y de Estudios Avanzados, Unidad Irapuato, Irapuato, Gto., CP 36821, Mexico
| | | | | |
Collapse
|
7
|
Lee J, Teitzel GM, Munkvold K, del Pozo O, Martin GB, Michelmore RW, Greenberg JT. Type III secretion and effectors shape the survival and growth pattern of Pseudomonas syringae on leaf surfaces. PLANT PHYSIOLOGY 2012; 158:1803-18. [PMID: 22319072 PMCID: PMC3320187 DOI: 10.1104/pp.111.190686] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 02/07/2012] [Indexed: 05/19/2023]
Abstract
The bacterium Pseudomonas syringae pv syringae B728a (PsyB728a) uses a type III secretion system (T3SS) to inject effector proteins into plant cells, a process that modulates the susceptibility of different plants to infection. Analysis of GREEN FLUORESCENT PROTEIN-expressing PsyB728a after spray inoculation without additives under moderate relative humidity conditions permitted (1) a detailed analysis of this strain's survival and growth pattern on host (Nicotiana benthamiana) and nonhost (tomato [Solanum lycopersicum]) leaf surfaces, (2) an assessment of the role of plant defenses in affecting PsyB728a leaf surface (epiphytic) growth, and (3) the contribution of the T3SS and specific effectors to PsyB728a epiphytic survival and growth. On host leaf surfaces, PsyB728a cells initially persist without growing, and show an increased population only after 48 h, unless plants are pretreated with the defense-inducing chemical benzothiazole. During the persistence period, some PsyB728a cells induce a T3SS reporter, whereas a T3SS-deficient mutant shows reduced survival. By 72 h, rare invasion by PsyB728a to the mesophyll region of host leaves occurs, but endophytic and epiphytic bacterial growths are not correlated. The effectors HopZ3 and HopAA1 delay the onset of epiphytic growth of PsyB728a on N. benthamiana, whereas they promote epiphytic survival/growth on tomato. These effectors localize to distinct sites in plant cells and likely have different mechanisms of action. HopZ3 may enzymatically modify host targets, as it requires residues important for the catalytic activity of other proteins in its family of proteases. Thus, the T3SS, HopAA1, HopZ3, and plant defenses strongly influence epiphytic survival and/or growth of PsyB728a.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Jean T. Greenberg
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637 (J.L., G.M.T., J.T.G.); Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (K.M., O.d.P., G.B.M.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (G.B.M.); The Genome Center, University of California, Davis, California 95616 (R.W.M.)
| |
Collapse
|
8
|
Büttner D, He SY. Type III protein secretion in plant pathogenic bacteria. PLANT PHYSIOLOGY 2009; 150:1656-64. [PMID: 19458111 PMCID: PMC2719110 DOI: 10.1104/pp.109.139089] [Citation(s) in RCA: 217] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 05/13/2009] [Indexed: 05/18/2023]
Affiliation(s)
- Daniela Büttner
- Institut für Biologie, Bereich Genetik, Martin-Luther-Universität Halle-Wittenberg, D-06099 Halle, Germany
| | | |
Collapse
|
9
|
Mattiuzzo M, Bandiera A, Gennaro R, Benincasa M, Pacor S, Antcheva N, Scocchi M. Role of the Escherichia coli SbmA in the antimicrobial activity of proline-rich peptides. Mol Microbiol 2007; 66:151-63. [PMID: 17725560 DOI: 10.1111/j.1365-2958.2007.05903.x] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In contrast to many antimicrobial peptides, members of the proline-rich group of antimicrobial peptides inactivate Gram-negative bacteria by a non-lytic mechanism. Several lines of evidence indicate that they are internalized into bacteria and their activity mediated by interaction with unknown cellular components. With the aim of identifying such interactors, we selected mutagenized Escherichia coli clones resistant to the proline-rich Bac7(1-35) peptide and analysed genes responsible for conferring resistance, whose products may thus be involved in the peptide's mode of action. We isolated a number of genomic regions bearing such genes, and one in particular coding for SbmA, an inner membrane protein predicted to be part of an ABC transporter. An E. coli strain carrying a point mutation in sbmA, as well as other sbmA-null mutants, in fact showed resistance to several proline-rich peptides but not to representative membranolytic peptides. Use of fluorescently labelled Bac7(1-35) confirmed that resistance correlated with a decreased ability to internalize the peptide, suggesting that a bacterial protein, SbmA, is necessary for the transport of, and for susceptibility to, proline-rich antimicrobial peptides of eukaryotic origin.
Collapse
Affiliation(s)
- Maura Mattiuzzo
- Department of Biochemistry, Biophysics and Macromolecular Chemistry, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy
| | | | | | | | | | | | | |
Collapse
|
10
|
Weber E, Koebnik R. Domain structure of HrpE, the Hrp pilus subunit of Xanthomonas campestris pv. vesicatoria. J Bacteriol 2005; 187:6175-86. [PMID: 16109959 PMCID: PMC1196163 DOI: 10.1128/jb.187.17.6175-6186.2005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The plant-pathogenic bacterium Xanthomonas campestris pv. vesicatoria possesses a type III secretion (TTS) system necessary for pathogenicity in susceptible hosts and induction of the hypersensitive response in resistant plants. This specialized protein transport system is encoded by a 23-kb hrp (hypersensitive response and pathogenicity) gene cluster. X. campestris pv. vesicatoria produces filamentous structures, Hrp pili, at the cell surface under hrp-inducing conditions. The Hrp pilus acts as a cell surface appendage of the TTS system and serves as a conduit for the transfer of bacterial effector proteins into the plant cell cytosol. The major pilus component, the HrpE pilin, is unique to xanthomonads and is encoded within the hrp gene cluster. In this study, functional domains of HrpE were mapped by linker-scanning mutagenesis and by reporter protein fusions to an N-terminally truncated avirulence protein (AvrBs3Delta2). Thirteen five-amino-acid peptide insertion mutants were obtained and could be grouped into six phenotypic classes. Three permissive mutations were mapped in the N-terminal half of HrpE, which is weakly conserved within the HrpE protein family. Four dominant-negative peptide insertions in the strongly conserved C-terminal region suggest that this domain is critical for oligomerization of the pilus subunits. Reporter protein fusions revealed that the N-terminal 17 amino acid residues act as an efficient TTS signal. From these results, we postulate a three-domain structure of HrpE with an N-terminal secretion signal, a surface-exposed variable region of the N-terminal half, and a C-terminal polymerization domain. Comparisons with a mutant study of HrpA, the Hrp pilin from Pseudomonas syringae pv. tomato DC3000, and hydrophobicity plot analyses of several nonhomologous Hrp pilins suggest a common architecture of Hrp pilins of different plant-pathogenic bacteria.
Collapse
Affiliation(s)
- Ernst Weber
- Institute of Genetics, Martin Luther University, D-06120 Halle, Germany
| | | |
Collapse
|
11
|
Kenjale R, Wilson J, Zenk SF, Saurya S, Picking WL, Picking WD, Blocker A. The needle component of the type III secreton of Shigella regulates the activity of the secretion apparatus. J Biol Chem 2005; 280:42929-37. [PMID: 16227202 DOI: 10.1074/jbc.m508377200] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Gram-negative bacteria commonly interact with eukaryotic host cells by using type III secretion systems (TTSSs or secretons). TTSSs serve to transfer bacterial proteins into host cells. Two translocators, IpaB and IpaC, are first inserted with the aid of IpaD by Shigella into the host cell membrane. Then at least two supplementary effectors of cell invasion, IpaA and IpgD, are transferred into the host cytoplasm. How TTSSs are induced to secrete is unknown, but their activation appears to require direct contact of the external distal tip of the apparatus with the host cell. The extracellular domain of the TTSS is a hollow needle protruding 60 nm beyond the bacterial surface. The monomeric unit of the Shigella flexneri needle, MxiH, forms a superhelical assembly. To probe the role of the needle in the activation of the TTSS for secretion, we examined the structure-function relationship of MxiH by mutagenesis. Most point mutations led to normal needle assembly, but some led to polymerization or possible length control defects. In other mutants, secretion was constitutively turned "on." In a further set, it was "constitutively on" but experimentally "uninducible." Finally, upon induction of secretion, some mutants released only the translocators and not the effectors. Most types of mutants were defective in interactions with host cells. Together, these data indicate that the needle directly controls the activity of the TTSS and suggest that it may be used to "sense" host cells.
Collapse
Affiliation(s)
- Roma Kenjale
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | | | | | | | | | | | | |
Collapse
|