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Lin L, Tao M, He WM, Wu QH, Huang HK, Murero AK, Shao XL, Wang LM, Qian GL. Identification of non-canonical antagonistic bacteria via interspecies contact-dependent killing. PEST MANAGEMENT SCIENCE 2024; 80:3997-4005. [PMID: 38527976 DOI: 10.1002/ps.8103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 01/18/2024] [Accepted: 03/26/2024] [Indexed: 03/27/2024]
Abstract
BACKGROUND Canonical biocontrol bacteria were considered to inhibit pathogenic bacteria mainly by secreting antibiotic metabolites or enzymes. Recent studies revealed that some biocontrol bacteria can inhibit pathogenic bacteria through contact-dependent killing (CDK) mediated by contact-dependent secretion systems. The CDK was independent of antibiotic metabolites and often ignored in normal biocontrol activity assay. RESULTS In this study, we aimed to use a pathogen enrichment strategy to isolate non-canonical bacteria with CDK ability. Rhizosphere soil samples from Chinese cabbage showing soft rot symptom were collected and Pectobacterium carotovorum subsp. carotovorum (Pcc), the pathogen of cabbage soft rot, were added into these samples to enrich bacteria which attached on Pcc cells. By co-culture with Pcc, four bacteria strains (named as PcE1, PcE8, PcE12 and PcE13) showing antibacterial activity were isolated from Chinese cabbage rhizosphere. These four bacteria strains showed CDK abilities to different pathogenic bacteria of horticultural plants. Among them, PcE1 was identified as Chryseobacterium cucumeris. Genome sequencing showed that PcE1 genome encoded a type VI secretion system (T6SS) gene cluster. By heterologous expression, four predicted T6SS effectors of PcE1 showed antibacterial activity to Escherichia coli. CONCLUSION Overall, this study isolated four bacteria strains with CDK activity to various horticultural plant pathogens, and revealed possible involvement of T6SS of Chryseobacterium cucumeris in antibacterial activity. These results provide valuable insight for potential application of CDK activity in biocontrol bacteria. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Long Lin
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Min Tao
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Wei-Mei He
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Qian-Hua Wu
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Hao-Kai Huang
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Aprodisia Kavutu Murero
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Xiao-Long Shao
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Li-Min Wang
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
| | - Guo-Liang Qian
- College of Plant Protection (State Key Laboratory of Biological Interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, P. R. China
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Cianciotto NP. The type II secretion system as an underappreciated and understudied mediator of interbacterial antagonism. Infect Immun 2024:e0020724. [PMID: 38980047 DOI: 10.1128/iai.00207-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024] Open
Abstract
Interbacterial antagonism involves all major phyla, occurs across the full range of ecological niches, and has great significance for the environment, clinical arena, and agricultural and industrial sectors. Though the earliest insight into interbacterial antagonism traces back to the discovery of antibiotics, a paradigm shift happened when it was learned that protein secretion systems (e.g., types VI and IV secretion systems) deliver toxic "effectors" against competitors. However, a link between interbacterial antagonism and the Gram-negative type II secretion system (T2SS), which exists in many pathogens and environmental species, is not evident in prior reviews on bacterial competition or T2SS function. A current examination of the literature revealed four examples of a T2SS or one of its known substrates having a bactericidal activity against a Gram-positive target or another Gram-negative. When further studied, the T2SS effectors proved to be peptidases that target the peptidoglycan of the competitor. There are also reports of various bacteriolytic enzymes occurring in the culture supernatants of some other Gram-negative species, and a link between these bactericidal activities and T2SS is suggested. Thus, a T2SS can be a mediator of interbacterial antagonism, and it is possible that many T2SSs have antibacterial outputs. Yet, at present, the T2SS remains relatively understudied for its role in interbacterial competition. Arguably, there is a need to analyze the T2SSs of a broader range of species for their role in interbacterial antagonism. Such investigation offers, among other things, a possible pathway toward developing new antimicrobials for treating disease.
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Affiliation(s)
- Nicholas P Cianciotto
- Department of Microbiology-Immunology, Northwestern University School of Medicine, Chicago, Illinois, USA
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Cobe BL, Dey S, Minasov G, Inniss N, Satchell KJF, Cianciotto NP. Bactericidal effectors of the Stenotrophomonas maltophilia type IV secretion system: functional definition of the nuclease TfdA and structural determination of TfcB. mBio 2024:e0119824. [PMID: 38832773 DOI: 10.1128/mbio.01198-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 04/28/2024] [Indexed: 06/05/2024] Open
Abstract
Stenotrophomonas maltophilia expresses a type IV protein secretion system (T4SS) that promotes contact-dependent killing of other bacteria and does so partly by secreting the effector TfcB. Here, we report the structure of TfcB, comprising an N-terminal domain similar to the catalytic domain of glycosyl hydrolase (GH-19) chitinases and a C-terminal domain for recognition and translocation by the T4SS. Utilizing a two-hybrid assay to measure effector interactions with the T4SS coupling protein VirD4, we documented the existence of five more T4SS substrates. One of these was protein 20845, an annotated nuclease. A S. maltophilia mutant lacking the gene for 20845 was impaired for killing Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Moreover, the cloned 20845 gene conferred robust toxicity, with the recombinant E. coli being rescued when 20845 was co-expressed with its cognate immunity protein. The 20845 effector was an 899 amino-acid protein, comprised of a GHH-nuclease domain in its N-terminus, a large central region of indeterminant function, and a C-terminus for secretion. Engineered variants of the 20845 gene that had mutations in the predicted catalytic site did not impede E. coli, indicating that the antibacterial effect of 20845 involves its nuclease activity. Using flow cytometry with DNA staining, we determined that 20845, but not its mutant variants, confers a loss in DNA content of target bacteria. Database searches revealed that uncharacterized homologs of 20845 occur within a range of bacteria. These data indicate that the S. maltophilia T4SS promotes interbacterial competition through the action of multiple toxic effectors, including a potent, novel DNase.IMPORTANCEStenotrophomonas maltophilia is a multi-drug-resistant, Gram-negative bacterium that is an emerging pathogen of humans. Patients with cystic fibrosis are particularly susceptible to S. maltophilia infection. In hospital water systems and various types of infections, S. maltophilia co-exists with other bacteria, including other pathogens such as Pseudomonas aeruginosa. We previously demonstrated that S. maltophilia has a functional VirB/D4 type VI protein secretion system (T4SS) that promotes contact-dependent killing of other bacteria. Since most work on antibacterial systems involves the type VI secretion system, this observation remains noteworthy. Moreover, S. maltophilia currently stands alone as a model for a human pathogen expressing an antibacterial T4SS. Using biochemical, genetic, and cell biological approaches, we now report both the discovery of a novel antibacterial nuclease (TfdA) and the first structural determination of a bactericidal T4SS effector (TfcB).
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Affiliation(s)
- Brandi L Cobe
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Supratim Dey
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Nicole Inniss
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Nicholas P Cianciotto
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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Gordils-Valentin L, Ouyang H, Qian L, Hong J, Zhu X. Conjugative type IV secretion systems enable bacterial antagonism that operates independently of plasmid transfer. Commun Biol 2024; 7:499. [PMID: 38664513 PMCID: PMC11045733 DOI: 10.1038/s42003-024-06192-8] [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: 06/20/2023] [Accepted: 04/15/2024] [Indexed: 04/28/2024] Open
Abstract
Bacterial cooperation and antagonism mediated by secretion systems are among the ways in which bacteria interact with one another. Here we report the discovery of an antagonistic property of a type IV secretion system (T4SS) sourced from a conjugative plasmid, RP4, using engineering approaches. We scrutinized the genetic determinants and suggested that this antagonistic activity is independent of molecular cargos, while we also elucidated the resistance genes. We further showed that a range of Gram-negative bacteria and a mixed bacterial population can be eliminated by this T4SS-dependent antagonism. Finally, we showed that such an antagonistic property is not limited to T4SS sourced from RP4, rather it can also be observed in a T4SS originated from another conjugative plasmid, namely R388. Our results are the first demonstration of conjugative T4SS-dependent antagonism between Gram-negative bacteria on the genetic level and provide the foundation for future mechanistic studies.
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Affiliation(s)
- Lois Gordils-Valentin
- Department of Chemical Engineering, Texas A&M University, College Station, 77843, TX, US
- Interdisciplinary Graduate Program in Genetics & Genomics, Texas A&M University, College Station, 77843, TX, US
| | - Huanrong Ouyang
- Department of Chemical Engineering, Texas A&M University, College Station, 77843, TX, US
| | - Liangyu Qian
- Department of Chemical Engineering, Texas A&M University, College Station, 77843, TX, US
| | - Joshua Hong
- Department of Biology, Texas A&M University, College Station, 77843, TX, US
| | - Xuejun Zhu
- Department of Chemical Engineering, Texas A&M University, College Station, 77843, TX, US.
- Interdisciplinary Graduate Program in Genetics & Genomics, Texas A&M University, College Station, 77843, TX, US.
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5
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Shao X, Wu Q, Li L, He W, He X, Cheng D, Murero A, Lin L, Wang L, Zhong C, Huang L, Qian G. Adapting the inoculation methods of kiwifruit canker disease to identify efficient biocontrol bacteria from branch microbiome. MOLECULAR PLANT PATHOLOGY 2024; 25:e13399. [PMID: 37921929 PMCID: PMC10788592 DOI: 10.1111/mpp.13399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/05/2023] [Accepted: 10/05/2023] [Indexed: 11/05/2023]
Abstract
Pseudomonas syringae pv. actinidiae (Psa), the bacterium that causes kiwifruit bacterial canker, is a common field occurrence that is difficult to control globally. Currently, exploring the resources for efficient biocontrol bacteria is a hot spot in the field. The common strategy for isolating biocontrol bacteria is to directly isolate biocontrol bacteria that can secrete diffusible antibacterial substances, most of which are members of Bacillus, Pseudomonas and Streptomycetaceae, from disease samples or soil. Here, we report a new approach by adapting the typical isolation methods of kiwifruit canker disease to identify efficient biocontrol bacteria from the branch microbiome. Using this unique approach, we isolated a group of kiwifruit biocontrol agents (KBAs) from the branch microbiome of Psa-resistant varieties. Thirteen of these showed no antagonistic activity in vitro, which depends on the secretion of antibacterial compounds. However, they exhibited antibacterial activity via cell-to-cell contacts mimicked by co-culture on agar plates. Through biocontrol tests on plants, two isolates, KBA13 and KBA19, demonstrated their effectiveness by protecting kiwifruit branches from Psa infection. Using KBA19, identified as Pantoea endophytica, as a representative, we found that this bacterium uses the type VI secretion system (T6SS) as the main contact-dependent antibacterial weapon that acts via translocating toxic effector proteins into Psa cells to induce cell death, and that this capacity expressed by KBA19 is common to various Psa strains from different countries. Our findings highlight a new strategy to identify efficient biocontrol agents that use the T6SS to function in an antibacterial metabolite-independent manner to control wood diseases.
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Affiliation(s)
- Xiaolong Shao
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Qianhua Wu
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Li Li
- CAS Engineering Laboratory for Kiwifruit Industrial Technology, CAS Key Laboratory of Plant Germplasm Enhancement and Specialty AgricultureWuhan Botanical Garden, Chinese Academy of SciencesWuhanHubei ProvinceChina
| | - Weimei He
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Xueting He
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Dongjin Cheng
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Aprodisia Murero
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Long Lin
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Limin Wang
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
| | - Caihong Zhong
- CAS Engineering Laboratory for Kiwifruit Industrial Technology, CAS Key Laboratory of Plant Germplasm Enhancement and Specialty AgricultureWuhan Botanical Garden, Chinese Academy of SciencesWuhanHubei ProvinceChina
| | - Lili Huang
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of Plant Protection, Northwest A&F UniversityYanglingShanxiChina
| | - Guoliang Qian
- Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant Protection, State Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural UniversityNanjingChina
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6
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Wang B, Zhang Z, Xu F, Yang Z, Li Z, Shen D, Wang L, Wu H, Li T, Yan Q, Wei Q, Shao X, Qian G. Soil bacterium manipulates antifungal weapons by sensing intracellular type IVA secretion system effectors of a competitor. THE ISME JOURNAL 2023; 17:2232-2246. [PMID: 37838821 PMCID: PMC10689834 DOI: 10.1038/s41396-023-01533-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 09/22/2023] [Accepted: 10/05/2023] [Indexed: 10/16/2023]
Abstract
Soil beneficial bacteria can effectively inhibit bacterial pathogens by assembling contact-dependent killing weapons, such as the type IVA secretion system (T4ASS). It's not clear whether these antibacterial weapons are involved in biotrophic microbial interactions in soil. Here we showed that an antifungal antibiotic 2,4-DAPG production of the soil bacterium, Pseudomonas protegens can be triggered by another soil bacterium, Lysobacter enzymogenes, via T4ASS by co-culturing on agar plates to mimic cell-to-cell contact. We demonstrated that the induced 2,4-DAPG production of P. protegens is achieved by intracellular detection of the T4ASS effector protein Le1519 translocated from L. enzymogenes. We defined Le1519 as LtaE (Lysobacter T4E triggering antifungal effects), which specifically stimulates the expression of 2,4-DAPG biosynthesis genes in P. protegens, thereby protecting soybean seedlings from infection by the fungus Rhizoctonia solani. We further found that LtaE directly bound to PhlF, a pathway-specific transcriptional repressor of the 2,4-DAPG biosynthesis, then activated the 2,4-DAPG production. Our results highlight a novel pattern of microbial interspecies and interkingdom interactions, providing a unique case for expanding the diversity of soil microbial interactions.
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Affiliation(s)
- Bingxin Wang
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Zeyu Zhang
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Fugui Xu
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Zixiang Yang
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Zihan Li
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Danyu Shen
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Limin Wang
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Huijun Wu
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Tao Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, PR China
| | - Qing Yan
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, 59717, USA
| | - Qi Wei
- Industrial Crops Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China
| | - Xiaolong Shao
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China
| | - Guoliang Qian
- College of Plant Protection (State Key Laboratory of Biological interactions and Crop Health; Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, Nanjing, 210095, P.R. China.
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Liao J, Li Z, Xiong D, Shen D, Wang L, Lin L, Shao X, Liao L, Li P, Zhang LQ, Wang HH, Qian G. Quorum quenching by a type IVA secretion system effector. THE ISME JOURNAL 2023; 17:1564-1577. [PMID: 37340074 PMCID: PMC10504344 DOI: 10.1038/s41396-023-01457-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/09/2023] [Accepted: 06/13/2023] [Indexed: 06/22/2023]
Abstract
Proteobacteria primarily utilize acyl-homoserine lactones (AHLs) as quorum-sensing signals for intra-/interspecies communication to control pathogen infections. Enzymatic degradation of AHL represents the major quorum-quenching mechanism that has been developed as a promising approach to prevent bacterial infections. Here we identified a novel quorum-quenching mechanism revealed by an effector of the type IVA secretion system (T4ASS) in bacterial interspecies competition. We found that the soil antifungal bacterium Lysobacter enzymogenes OH11 (OH11) could use T4ASS to deliver the effector protein Le1288 into the cytoplasm of another soil microbiome bacterium Pseudomonas fluorescens 2P24 (2P24). Le1288 did not degrade AHL, whereas its delivery to strain 2P24 significantly impaired AHL production through binding to the AHL synthase PcoI. Therefore, we defined Le1288 as LqqE1 (Lysobacter quorum-quenching effector 1). Formation of the LqqE1-PcoI complex enabled LqqE1 to block the ability of PcoI to recognize/bind S-adenosy-L-methionine, a substrate required for AHL synthesis. This LqqE1-triggered interspecies quorum-quenching in bacteria seemed to be of key ecological significance, as it conferred strain OH11 a better competitive advantage in killing strain 2P24 via cell-to-cell contact. This novel quorum-quenching also appeared to be adopted by other T4ASS-production bacteria. Our findings suggest a novel quorum-quenching that occurred naturally in bacterial interspecies interactions within the soil microbiome by effector translocation. Finally, we presented two case studies showing the application potential of LqqE1 to block AHL signaling in the human pathogen Pseudomonas aeruginosa and the plant pathogen Ralstonia solanacearum.
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Affiliation(s)
- Jinxing Liao
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Zihan Li
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Dan Xiong
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Danyu Shen
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Limin Wang
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Long Lin
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Xiaolong Shao
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China
| | - Lisheng Liao
- Integrative Microbiology Research Centre, South China Agricultural University, 510642, Guangzhou, People's Republic of China
| | - Peng Li
- Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life Sciences, Hainan Normal University, Haikou, China
| | - Li-Qun Zhang
- Department of Plant Pathology, China Agricultural University, Beijing, China
| | - Hai-Hong Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Guoliang Qian
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China.
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Shen X, Yang Z, Li Z, Xiong D, Liao J, He W, Shen D, Shao X, Niu B, He Y, Gao Y, Qian G. Identification of atypical T4SS effector proteins mediating bacterial defense. MLIFE 2023; 2:295-307. [PMID: 38817810 PMCID: PMC10989847 DOI: 10.1002/mlf2.12084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/26/2023] [Accepted: 07/07/2023] [Indexed: 06/01/2024]
Abstract
To remain competitive, proteobacteria use various contact-dependent weapon systems to defend against microbial competitors. The bacterial-killing type IV secretion system (T4SS) is one such powerful weapon. It commonly controls the killing/competition between species by secreting the lethal T4SS effector (T4E) proteins carrying conserved XVIPCD domains into competing cells. In this study, we sought knowledge to understand whether the bacterial-killing T4SS-producing bacteria encode T4E-like proteins and further explore their biological functions. To achieve this, we designed a T4E-guided approach to discover T4E-like proteins that are designated as atypical T4Es. Initially, this approach required scientists to perform simple BlastP search to identify T4E homologs that lack the XVIPCD domain in the genomes of T4SS-producing bacteria. These homologous genes were then screened in Escherichia coli to identify antibacterial candidates (atypical T4Es) and their neighboring detoxification proteins, followed by testing their gene cotranscription and validating their physical interactions. Using this approach, we did discover two atypical T4E proteins from the plant-beneficial Lysobacter enzymogenes and the phytopathogen Xanthomonas citri. We also provided substantial evidence to show that the atypical T4E protein Le1637-mediated bacterial defense in interspecies interactions between L. enzymogenes and its competitors. Therefore, the newly designed T4E-guided approach holds promise for detecting functional atypical T4E proteins in bacterial cells.
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Affiliation(s)
- Xi Shen
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Zixiang Yang
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Zihan Li
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Dan Xiong
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Jinxing Liao
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Weimei He
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Danyu Shen
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Xiaolong Shao
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
| | - Ben Niu
- College of Life ScienceNortheast Forestry UniversityHarbinChina
| | - Yongxing He
- Ministry of Education Key Laboratory of Cell Activities and Stress AdaptationsLanzhou UniversityLanzhouChina
| | - Yong‐Gui Gao
- School of Biological SciencesNanyang Technological UniversitySingaporeSingapore
| | - Guoliang Qian
- State Key Laboratory of Biological Interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
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Lin L, Li L, Tao M, Wu Q, Zhou L, Wang B, Wang L, Shao X, Zhong C, Qian G. Assembly of an active microbial consortium by engineering compatible combinations containing foreign and native biocontrol bacteria of kiwifruit. Comput Struct Biotechnol J 2023; 21:3672-3679. [PMID: 37576746 PMCID: PMC10412838 DOI: 10.1016/j.csbj.2023.07.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/12/2023] [Accepted: 07/19/2023] [Indexed: 08/15/2023] Open
Abstract
Assembling functional bacterial biocontrol consortia is expected to expand the scope and efficiency of biocontrol agents. Generally, bacterial interspecies interactions lead to incompatibility events, as bacteria can produce antibacterial compounds and/or assemble contact-dependent killing (CDK) devices. Here, we aimed to assemble a bacterial consortium comprising Lysobacter enzymogenes OH11 and Bacillus safensis ZK-1 for the synergistic control of bacterial and fungal diseases of kiwifruit. ZK-1, a native kiwifruit biocontrol bacterium, is effective against Pseudomonas syringae pv. actinidiae (Psa) that causes bacterial kiwifruit canker, but has weak antifungal activity. OH11 is a foreign kiwifruit biocontrol agent with strong antifungal activity. While OH11 was unable to produce anti-Gram-negative metabolites, this strain could utilize type IV secretion system as an antibacterial CDK weapon. We first observed that OH11 could inhibit growth of ZK-1 by generating diffusible anti-Gram-positive antibiotic WAP-8294A2, whereas ZK-1 failed to generate diffusible antibacterial compound to inhibit growth of OH11. To disrupt this interspecies incompatibility, we generated a transgenic OH11-derived strain, OH11W, by deleting the WAP-8294A2 biosynthetic gene and found that OH11W did not kill ZK-1. We further observed that when OH11W and ZK-1 were co-inoculated on agar plates, no CDK effect was observed between them, whereas co-culture of OH11W or ZK-1 with Psa on agar plates resulted in Psa killing, suggesting L. enzymogenes and B. safensis assemble antibacterial CDK weapons against bacterial pathogens, and these CDK weapons did not affect the compatibility between OH11W and ZK-1. Based on these findings, we assembled an OH11W/ZK-1 dependent consortium that was shown to be functional in controlling bacterial canker and several representative fungal diseases of kiwifruit.
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Affiliation(s)
- Long Lin
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Li Li
- CAS Engineering Laboratory for Kiwifruit Industrial Technology, CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei Province 430074, China
| | - Min Tao
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Qianhua Wu
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Longteng Zhou
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Bozhen Wang
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Limin Wang
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiaolong Shao
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Caihong Zhong
- CAS Engineering Laboratory for Kiwifruit Industrial Technology, CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei Province 430074, China
| | - Guoliang Qian
- Key Laboratory of Biological interactions and Crop Health, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, PR China
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10
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Afoshin A, Kudryakova I, Tarlachkov S, Leontyevskaya E, Zelenov D, Rudenko P, Leontyevskaya Vasilyeva N. Transcriptomic Analysis Followed by the Isolation of Extracellular Bacteriolytic Proteases from Lysobacter capsici VKM B-2533 T. Int J Mol Sci 2023; 24:11652. [PMID: 37511410 PMCID: PMC10380237 DOI: 10.3390/ijms241411652] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/13/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
The aim of the study was to search for, isolate and characterize new bacteriolytic enzymes that show promising potential for their use in medicine, agriculture and veterinary. Using a transcriptomic analysis, we annotated in Lysobacter capsici VKM B-2533T the genes of known bacteriolytic and antifungal enzymes, as well as of antibiotics, whose expression levels increased when cultivated on media conducive to the production of antimicrobial agents. The genes of the secreted putative bacteriolytic proteases were also annotated. Two new bacteriolytic proteases, Serp and Serp3, were isolated and characterized. The maximum bacteriolytic activities of Serp and Serp3 were exhibited at low ionic strength of 10 mM Tris-HCl, and high temperatures of, respectively, 80 °C and 70 °C. The pH optimum for Serp was 8.0; for Serp3, it was slightly acidic, at 6.0. Both enzymes hydrolyzed autoclaved cells of Micrococcus luteus Ac-2230T, Proteus vulgaris H-19, Pseudomonas aeruginosa and Staphylococcus aureus 209P. Serp also digested cells of Bacillus cereus 217. Both enzymes hydrolyzed casein and azofibrin. The newly discovered enzymes are promising for developing proteolytic antimicrobial drugs on their basis.
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Affiliation(s)
- Alexey Afoshin
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
| | - Irina Kudryakova
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
| | - Sergey Tarlachkov
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
| | - Elena Leontyevskaya
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
| | - Dmitry Zelenov
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
- Pushchino Branch of the Federal State Budgetary Educational Institution of Higher Education «Russian Biotechnological University (BIOTECH University)», 3 Institutskaya Str., Pushchino 142290, Russia
| | - Pavel Rudenko
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
| | - Natalya Leontyevskaya Vasilyeva
- Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, FRC PSCBR, Russian Academy of Sciences, 5 Prosp. Nauki, Pushchino 142290, Russia
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11
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Yang P, Qu C, Yuan M, Xi B, Jia X, Zhang B, Zhang L. Genetic Basis and Expression Pattern Indicate the Biocontrol Potential and Soil Adaption of Lysobacter capsici CK09. Microorganisms 2023; 11:1768. [PMID: 37512940 PMCID: PMC10384520 DOI: 10.3390/microorganisms11071768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
Lysobacter species have attracted increasing attention in recent years due to their capacities to produce diverse secondary metabolites against phytopathogens. In this research, we analyzed the genomic and transcriptomic patterns of Lysobacter capsici CK09. Our data showed that L. capsici CK09 harbored various contact-independent biocontrol traits, such as fungal cell wall lytic enzymes and HSAF/WAP-8294A2 biosynthesis, as well as several contact-dependent machineries, including type 2/4/6 secretion systems. Additionally, a variety of hydrolytic enzymes, particularly extracellular enzymes, were found in the L. capsici CK09 genome and predicted to improve its adaption in soil. Furthermore, several systems, including type 4 pili, type 3 secretion system and polysaccharide biosynthesis, can provide a selective advantage to L. capsici CK09, enabling the species to live on the surface in soil. The expression of these genes was then confirmed via transcriptomic analysis, indicating the activities of these genes. Collectively, our research provides a comprehensive understanding of the biocontrol potential and soil adaption of L. capsici CK09 and implies the potential of this strain for application in the future.
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Affiliation(s)
- Pu Yang
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Chaofan Qu
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Miaomiao Yuan
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Bo Xi
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Xiu Jia
- Institute of Biodiversity, Faculty of Biological Sciences, Cluster of Excellence Balance of the Microverse, Friedrich Schiller University Jena, 07745 Jena, Germany
| | - Ben Zhang
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Lizhen Zhang
- School of Life Science, Shanxi University, Taiyuan 030006, China
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12
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Zhu Y, Dou Q, Du L, Wang Y. QseB/QseC: a two-component system globally regulating bacterial behaviors. Trends Microbiol 2023:S0966-842X(23)00046-X. [PMID: 36849330 DOI: 10.1016/j.tim.2023.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 03/01/2023]
Abstract
QseB/QseC is a two-component system that is involved in the regulation of multiple bacterial behaviors by regulating quorum sensing, bacterial pathogenicity, and antibiotic resistance. Thus, QseB/QseC could provide a target for new antibiotic development. Recently, QseB/QseC has been found to confer survival advantages to environmental bacteria under stress conditions. The molecular mechanistic understanding of QseB/QseC has become an active area of research and revealed some emerging themes, including a deeper understanding of QseB/QseC regulation in different pathogens and environmental bacteria, the functional difference of QseB/QseC among species, and the possibility of analyzing QseB/QseC evolution. Here, we discuss the progression of QseB/QseC studies and describe several unresolved issues and future directions. Resolving these issues is among the challenges of future QseB/QseC studies.
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Affiliation(s)
- Yuxiang Zhu
- College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Qin Dou
- College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Liangcheng Du
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Yan Wang
- College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China.
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13
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Suaifan GARY, Abdel Rahman DMA, Abu-Odeh AM, Abu Jbara F, Shehadeh MB, Darwish RM. Antibiotic-Lysobacter enzymogenes proteases combination as a novel virulence attenuating therapy. PLoS One 2023; 18:e0282705. [PMID: 36893145 PMCID: PMC9997937 DOI: 10.1371/journal.pone.0282705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 02/17/2023] [Indexed: 03/10/2023] Open
Abstract
Minimizing antibiotic resistance is a key motivation strategy in designing and developing new and combination therapy. In this study, a combination of the antibiotics (cefixime, levofloxacin and gentamicin) with Lysobacter enzymogenes (L. enzymogenes) bioactive proteases present in the cell- free supernatant (CFS) have been investigated against the Gram-positive methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA) and the Gram-negative Escherichia coli (E. coli O157:H7). Results indicated that L. enzymogenes CFS had maximum proteolytic activity after 11 days of incubation and higher growth inhibitory properties against MSSA and MRSA compared to E. coli (O157:H7). The combination of L. enzymogenes CFS with cefixime, gentamicin and levofloxacin at sub-MIC levels, has potentiated their bacterial inhibition capacity. Interestingly, combining cefixime with L. enzymogenes CFS restored its antibacterial activity against MRSA. The MTT assay revealed that L. enzymogenes CFS has no significant reduction in human normal skin fibroblast (CCD-1064SK) cell viability. In conclusion, L. enzymogenes bioactive proteases are natural potentiators for antimicrobials with different bacterial targets including cefixime, gentamicin and levofloxacin representing the beginning of a modern and efficient era in the battle against multidrug-resistant pathogens.
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Affiliation(s)
- Ghadeer A. R. Y. Suaifan
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
- * E-mail: ,
| | - Diana M. A. Abdel Rahman
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
| | - Ala’ M. Abu-Odeh
- Department of Pharmaceutical Chemistry and Pharmacognosy, School of Pharmacy, Applied Science Private University, Jordan, Amman
| | | | - Mayadah B. Shehadeh
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
| | - Rula M. Darwish
- Department of Pharmaceutics and Pharmaceutical Biotechnology, School of Pharmacy, The University of Jordan, Amman, Jordan
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14
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Thiery S, Turowski P, Berleman JE, Kaimer C. The predatory soil bacterium Myxococcus xanthus combines a Tad- and an atypical type 3-like protein secretion system to kill bacterial cells. Cell Rep 2022; 40:111340. [PMID: 36103818 DOI: 10.1016/j.celrep.2022.111340] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 06/20/2022] [Accepted: 08/18/2022] [Indexed: 11/03/2022] Open
Abstract
Predatory Myxobacteria employ a multilayered predation strategy to kill and lyse soil microorganisms. Aiming to dissect the mechanism of contact-dependent killing of bacteria, we analyze four protein secretion systems in Myxococcus xanthus and investigate the predation of mutant strains on different timescales. We find that a Tad-like and a type 3-like secretion system (Tad and T3SS∗) fulfill distinct functions during contact-dependent prey killing: the Tad-like system is necessary to induce prey cell death, while the needle-less T3SS∗ initiates prey lysis. Fluorescence microscopy reveals that components of both systems interdependently localize to the predator-prey contact site prior to killing. Swarm expansion assays show that both Tad and T3SS∗ are required to handle live prey and that nutrient extraction from prey bacteria is sufficient to power M. xanthus motility. In conclusion, our observations indicate the functional interplay of two types of secretion systems for killing and lysis of bacterial cells.
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Affiliation(s)
- Susanne Thiery
- Department of Biology and Biotechnology, Microbial Biology, Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - Pia Turowski
- Department of Biology and Biotechnology, Microbial Biology, Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - James E Berleman
- Department of Biology, St. Mary's College, Moraga, CA 94556, USA
| | - Christine Kaimer
- Department of Biology and Biotechnology, Microbial Biology, Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany.
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15
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Xu S, Zhang Z, Xie X, Shi Y, Chai A, Fan T, Li B, Li L. Comparative genomics provides insights into the potential biocontrol mechanism of two Lysobacter enzymogenes strains with distinct antagonistic activities. Front Microbiol 2022; 13:966986. [PMID: 36033849 PMCID: PMC9410377 DOI: 10.3389/fmicb.2022.966986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 07/27/2022] [Indexed: 11/29/2022] Open
Abstract
Lysobacter enzymogenes has been applied as an abundant beneficial microorganism to control plant disease; however, most L. enzymogenes strains have been mainly reported to control fungal diseases, not bacterial diseases. In this study, two L. enzymogenes strains were characterized, of which CX03 displayed a broad spectrum of antagonistic activities toward multiple bacteria, while CX06 exhibited a broad spectrum of antagonistic activities toward diverse fungi and oomycete, and the whole genomes of the two strains were sequenced and compared. The genome annotation showed that the CX03 genome comprised a 5,947,018 bp circular chromosome, while strain CX06 comprised a circular 6,206,196 bp chromosome. Phylogenetic analysis revealed that CX03 had a closer genetic relationship with L. enzymogenes ATCC29487T and M497-1, while CX06 was highly similar to L. enzymogenes C3. Functional gene annotation analyses of the two L. enzymogenes strains showed that many genes or gene clusters associated with the biosynthesis of different secondary metabolites were found in strains CX03 and CX06, which may be responsible for the different antagonistic activities against diverse plant pathogens. Moreover, comparative genomic analysis revealed the difference in bacterial secretory systems between L. enzymogenes strains CX03 and CX06. In addition, numerous conserved genes related to siderophore biosynthesis, quorum sensing, two-component systems, flagellar biosynthesis and chemotaxis were also identified in the genomes of strains CX03 and CX06. Most reported L. enzymogenes strains were proven mainly to suppress fungi, while CX03 exhibited direct inhibitory activities toward plant bacterial pathogens and showed an obvious role in managing bacterial disease. This study provides a novel understanding of the biocontrol mechanisms of L. enzymogenes, and reveals great potential for its application in plant disease control.
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16
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Novel indole-mediated potassium ion import system confers a survival advantage to the Xanthomonadaceae family. THE ISME JOURNAL 2022; 16:1717-1729. [PMID: 35319020 DOI: 10.1038/s41396-022-01219-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 12/30/2022]
Abstract
Interspecific and intraspecific communication systems of microorganisms are involved in the regulation of various stress responses in microbial communities. Although the significance of signaling molecules in the ubiquitous family Xanthomonadaceae has been reported, the role bacterial communications play and their internal mechanisms are largely unknown. Here, we use Lysobacter enzymogenes, a member of Xanthomonadaceae, to identify a novel potassium ion import system, LeKdpXFABC. This import system participates in the indole-mediated interspecies signaling pathway and matters in environmental adaptation. Compared with the previously reported kdpFABC of Escherichia coli, LekdpXFABC contains a novel indispensable gene LekdpX and is directly regulated by the indole-related two-component system QseC/B. QseC autophosphorylation is involved in this process. The operon LekdpXFABC widely exists in Xanthomonadaceae. Moreover, indole promotes antimicrobial product production at the early exponential phase. Further analyses show that indole enhances potassium ion adsorption on the cell surface by upregulating the production of O-antigenic polysaccharides. Finally, we confirm that LeKdpXFABC mediation by indole is subject to the intraspecific signaling molecules DSFs, of which the biosynthesis genes always exist together with LekdpXFABC. Therefore, as a new idea, the signal collaborative strategy of indole and DSFs might ensure the persistent fitness advantage of Xanthomonadaceae in variable environments.
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17
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Wu Q, Wang B, Shen X, Shen D, Wang B, Guo Q, Li T, Shao X, Qian G. Unlocking the bacterial contact-dependent antibacterial activity to engineer a biocontrol alliance of two species from natural incompatibility to artificial compatibility. STRESS BIOLOGY 2021; 1:19. [PMID: 37676524 PMCID: PMC10441968 DOI: 10.1007/s44154-021-00018-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/22/2021] [Indexed: 09/08/2023]
Abstract
Plant growth-promoting rhizobacteria (PGPR) contain various biocontrol bacteria with broad-spectrum antimicrobial activity, and their single species has been extensively applied to control crop diseases. The development of complex biocontrol community by mixing two or more PGPR members together is a promising strategy to enlarge the efficacy and scope of biocontrol. However, an effective method to assess the natural compatibility of PGPR members has not yet been established to date. Here, we developed such a tool by using the bacterial contact-dependent antibacterial activity (CDAA) as a probe. We showed that the CDAA events are common in two-species interactions in the four selected representative PGPRs, represented by the incompatible interaction of Lysobacter enzymogenes strain OH11 (OH11) and Lysobacter antibioticus strain OH13 (OH13). We further showed that the CDAA between OH11 and OH13 is jointly controlled by a contact-dependent killing device, called the type IV secretion system (T4SS). By deleting the respective T4SS synthesis genes, the T4SS in both strains was co-inactivated and this step unlocked their natural CDAA, resulting in an engineered, compatible mutant alliance that co-displayed antibacterial and antifungal activity. Therefore, this study reveals that releasing bacterial CDAA is effective to rationally engineer the biocontrol community.
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Affiliation(s)
- Qianhua Wu
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Bozhen Wang
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Xi Shen
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Danyu Shen
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Bingxin Wang
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Qinggang Guo
- Institute of Plant Protection, Hebei Academy of Agricultural and Forestry Sciences, Integrated Pest Management Center of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs of China, Baoding, 071000, People's Republic of China
| | - Tao Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, People's Republic of China
| | - Xiaolong Shao
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Guoliang Qian
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China.
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18
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Bejarano A, Perazzolli M, Pertot I, Puopolo G. The Perception of Rhizosphere Bacterial Communication Signals Leads to Transcriptome Reprogramming in Lysobacter capsici AZ78, a Plant Beneficial Bacterium. Front Microbiol 2021; 12:725403. [PMID: 34489914 PMCID: PMC8416617 DOI: 10.3389/fmicb.2021.725403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022] Open
Abstract
The rhizosphere is a dynamic region governed by complex microbial interactions where diffusible communication signals produced by bacteria continuously shape the gene expression patterns of individual species and regulate fundamental traits for adaptation to the rhizosphere environment. Lysobacter spp. are common bacterial inhabitants of the rhizosphere and have been frequently associated with soil disease suppressiveness. However, little is known about their ecology and how diffusible communication signals might affect their behavior in the rhizosphere. To shed light on the aspects determining rhizosphere competence and functioning of Lysobacter spp., we carried out a functional and transcriptome analysis on the plant beneficial bacterium Lysobacter capsici AZ78 (AZ78) grown in the presence of the most common diffusible communication signals released by rhizosphere bacteria. Mining the genome of AZ78 and other Lysobacter spp. showed that Lysobacter spp. share genes involved in the production and perception of diffusible signal factors, indole, diffusible factors, and N-acyl-homoserine lactones. Most of the tested diffusible communication signals (i.e., indole and glyoxylic acid) influenced the ability of AZ78 to inhibit the growth of the phytopathogenic oomycete Pythium ultimum and the Gram-positive bacterium Rhodococcus fascians. Moreover, RNA-Seq analysis revealed that nearly 21% of all genes in AZ78 genome were modulated by diffusible communication signals. 13-Methyltetradecanoic acid, glyoxylic acid, and 2,3-butanedione positively influenced the expression of genes related to type IV pilus, which might enable AZ78 to rapidly colonize the rhizosphere. Moreover, glyoxylic acid and 2,3-butanedione downregulated tRNA genes, possibly as a result of the elicitation of biological stress responses. On its behalf, indole downregulated genes related to type IV pilus and the heat-stable antifungal factor, which might result in impairment of twitching motility and antibiotic production in AZ78. These results show that diffusible communication signals may affect the ecology of Lysobacter spp. in the rhizosphere and suggest that diffusible communication signals might be used to foster rhizosphere colonization and functioning of plant beneficial bacteria belonging to the genus Lysobacter.
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Affiliation(s)
- Ana Bejarano
- Center of Agriculture, Food, Environment, University of Trento, San Michele all'Adige, Italy.,Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
| | - Michele Perazzolli
- Center of Agriculture, Food, Environment, University of Trento, San Michele all'Adige, Italy.,Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
| | - Ilaria Pertot
- Center of Agriculture, Food, Environment, University of Trento, San Michele all'Adige, Italy.,Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
| | - Gerardo Puopolo
- Center of Agriculture, Food, Environment, University of Trento, San Michele all'Adige, Italy.,Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
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