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Choudhary BK, Choudhary M, Barbuddhe SB, Shanker A. Partial genomic characterization of Chromobacterium piscinae from India reveals multi drug resistance. Braz J Microbiol 2024; 55:1557-1567. [PMID: 38374322 PMCID: PMC11153472 DOI: 10.1007/s42770-024-01288-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/10/2024] [Indexed: 02/21/2024] Open
Abstract
Species of genus Chromobacterium have been isolated from diverse geographical settings, which exhibits significant metabolic flexibility as well as biotechnological and pathogenic properties. This study describes the isolation, characterization, draft assembly, and detailed sequence analysis of Chromobacterium piscinae strain W1B-CG-NIBSM isolated from water samples from multi use community pond. The organism was characterized by biochemical tests, Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI TOF-MS) and partial genome sequencing. The partial genomic data of Chromobacterium pisciane isolate W1B NIBSM strain was submitted to GenBank with Bio project number PRJNA803347 and accession no CP092474. An integrated genome analysis of Chromobacterium piscinae has been accomplished with PATRIC which indicates good quality genome. DNA sequencing using the illumina HiSeq 4000 system generated total length of 4,155,481 bp with 63 contig with G + C content is 62.69%. This partial genome contains 4,126 protein-coding sequences (CDS), 27 repeats region and 78 transfer RNA (tRNA) genes as well as 3 ribosomal RNA (rRNA) genes. The genomic annotation of Chromobacterium W1B depicts 2,925 proteins with functional assignments and 1201 hypothetical proteins. A repertoire of specialty genes implicated in antibiotic resistance (45 genes), drug target (6 genes), Transporter (3 genes) and virulence factor (10 genes). The genomic analysis reveals the adaptability, displays metabolic varied pathways and shows specific structural complex and various virulence factors which makes this strain multi drug resistant. The isolate was found to be highly resistant to β-lactam antibiotics whereas it showed sensitivity towards aminoglycosides and fluoroquinolone antibiotics. Hence, the recovery of Chromobacterium piscinae from community pond evidenced for uncertain hidden source of public health hazard. To the best of authors knowledge this is first report of isolation and genomic description of C. piscinae from India.
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Affiliation(s)
- Binod Kumar Choudhary
- Indian Council of Agricultural Research-National Institute of Biotic Stress Management, Baronda, Raipur, 493 225, Chhattisgarh, India.
| | - Mamta Choudhary
- Indian Council of Agricultural Research-National Institute of Biotic Stress Management, Baronda, Raipur, 493 225, Chhattisgarh, India
| | | | - Asheesh Shanker
- Department of Bioinformatics, Central University of South Bihar, Gaya, Bihar, 824236, India
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2
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Kang Z, Martinson VG, Wang Y, Coon KL, Valzania L, Strand MR. Increased environmental microbial diversity reduces the disease risk of a mosquitocidal pathogen. mBio 2024; 15:e0272623. [PMID: 38055338 PMCID: PMC10790785 DOI: 10.1128/mbio.02726-23] [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: 10/11/2023] [Accepted: 10/25/2023] [Indexed: 12/08/2023] Open
Abstract
IMPORTANCE The host-specific microbiotas of animals can both reduce and increase disease risks from pathogens. In contrast, how environmental microbial communities affect pathogens is largely unexplored. Aquatic habitats are of interest because water enables environmental microbes to readily interact with animal pathogens. Here, we focused on mosquitoes, which are important disease vectors as terrestrial adults but are strictly aquatic as larvae. We identified a pathogen of mosquito larvae from the field as a strain of Chromobacterium haemolyticum. Comparative genomic analyses and functional assays indicate this strain and other Chromobacterium are mosquitocidal but are also opportunistic pathogens of other animals. We also identify a critical role for diversity of the environmental microbiota in disease risk. Our study characterizes both the virulence mechanisms of a pathogen and the role of the environmental microbiota in disease risk to an aquatic animal of significant importance to human health.
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Affiliation(s)
- Zhiwei Kang
- Hebei University, College of Life Sciences, Baoding, Hebei, China
| | - Vincent G. Martinson
- Department of Entomology, University of Georgia, Athens, Georgia, USA
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Yin Wang
- Department of Entomology, University of Georgia, Athens, Georgia, USA
| | - Kerri L. Coon
- Department of Entomology, University of Georgia, Athens, Georgia, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Luca Valzania
- Department of Entomology, University of Georgia, Athens, Georgia, USA
- Institut Curie, Paris, France
| | - Michael R. Strand
- Department of Entomology, University of Georgia, Athens, Georgia, USA
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3
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Choi SY, Mun W, Choi S, Lee K, Mitchell RJ. Bdellovibrio svalbardensis sp. nov., a newly described predator isolated from Svalbard, Norway. Int J Syst Evol Microbiol 2024; 74. [PMID: 38265430 DOI: 10.1099/ijsem.0.006248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024] Open
Abstract
Identified as a newly described species from a biocrust in Svalbard, Norway (78° 54' 8.27″ N 12° 01' 20.34″ E), isolate PAP01T has different characteristics from any known predatory bacteria. The isolate was vibrio-shaped strain that employed flagellar motility. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate clustered within the genus Bdellovibrio in the family Bdellovibrionaceae. 16S rRNA gene sequence similarities between strain PAP01T and the type strain (Bdellovibrio bacteriovorus HD100) was 95.7 %. The PAP01T genome has a size of 3.898 Mbp and possesses 3732 genes and a G+C content of 45.7 mol%. The results of genetic and physiological tests indicated the phenotypic differentiation of strain PAP01T from the two other Bdellovibrio species with validly published names. Based on the physiological and phylogenetic data, as well as the prey range spectrum and osmolality sensitivities, isolate PAP01T represents a novel species within the genus Bdellovibrio, for which the name Bdellovibrio svalbardensis sp. nov. is proposed. The type strain is PAP01T (=KCTC 92583T=DSM 115080T).
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Affiliation(s)
- Seong Yeol Choi
- School of Life Sciences, Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
- Bioneer Corporation, Daejeon, Republic of Korea
| | - Wonsik Mun
- School of Life Sciences, Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Sumin Choi
- School of Life Sciences, Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Kyoung Lee
- Department of Bio Health Science, Changwon National University, Changwon, Republic of Korea
| | - Robert J Mitchell
- School of Life Sciences, Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
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4
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Loo C, Koirala P, Smith NC, Evans KC, Benomar S, Parisi IR, Oller A, Chandler JR. Cross-species activation of hydrogen cyanide production by a promiscuous quorum-sensing receptor promotes Chromobacterium subtsugae competition in a dual-species model. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36790401 DOI: 10.1099/mic.0.001294] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Many saprophytic bacteria have LuxR-I-type acyl-homoserine lactone (AHL) quorum-sensing systems that may be important for competing with other bacteria in complex soil communities. LuxR AHL receptors specifically interact with cognate AHLs to cause changes in expression of target genes. Some LuxR-type AHL receptors have relaxed specificity and are responsive to non-cognate AHLs. These promiscuous receptors might be used to sense and respond to AHLs produced by other bacteria by eavesdropping. We are interested in understanding the role of eavesdropping during interspecies competition. The soil saprophyte Chromobacterium subtsugae has a single AHL circuit, CviR-I, which produces and responds to N-hexanoyl-HSL (C6-HSL). The AHL receptor CviR can respond to a variety of AHLs in addition to C6-HSL. In prior studies we have utilized a coculture model with C. subtsugae and another soil saprophyte, Burkholderia thailandensis. Using this model, we previously showed that promiscuous activation of CviR by B. thailandensis AHLs provides a competitive advantage to C. subtsugae. Here, we show that B. thailandensis AHLs activate transcription of dozens of genes in C. subtsugae, including the hcnABC genes coding for production of hydrogen cyanide. We show that hydrogen cyanide production is population density-dependent and demonstrate that the cross-induction of hydrogen cyanide by B. thailandensis AHLs provides a competitive advantage to C. subtsugae. Our results provide new information on C. subtsugae quorum sensing and are the basis for future studies aimed at understanding the role of eavesdropping in interspecies competition.
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Affiliation(s)
- Cheyenne Loo
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.,Present address: Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Pratik Koirala
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Nathan C Smith
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Kara C Evans
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.,Present address: International Flavors and Fragrances Health and Biosciences, Madison WI, 53716, USA
| | - Saida Benomar
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.,Present address: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta GA, 30322, USA
| | - Isabelle R Parisi
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Anna Oller
- Department of Biological and Clinical Sciences, University of Central Missouri, Warrensburg, MO 64093, USA
| | - Josephine R Chandler
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
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5
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Ezzedine JA, Scheifler M, Desdevises Y, Jacquet S. A Comparative Study of the Dynamics and Diversity of Bdellovibrio and Like Organisms in Lakes Annecy and Geneva. Microorganisms 2022; 10:microorganisms10101960. [PMID: 36296236 PMCID: PMC9610775 DOI: 10.3390/microorganisms10101960] [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: 08/23/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 12/02/2022] Open
Abstract
Bdellovibrio and like organisms (BALOs) are obligate bacterial predators of other Gram-negative bacteria. Here, we used quantitative PCR (qPCR) and recently developed specific primers which target the 16S rRNA gene to explore the abundance and distribution of three families of BALO belonging to the Oligoflexia class (i.e., Bdellovibrionaceae, Peredibacteraceae and Bacteriovoracaceae) over one year in the epilimnion and hypolimnion of Lakes Annecy and Geneva. Peredibacteraceae was the dominant group at all sampling points except at the bottom of Lake Geneva, where Bdellovibrionaceae was found in higher number. In addition, the abundance of BALOs increased significantly during the warmer months. Using high-throughput sequencing (Illumina Miseq), hundreds of OTUs were identified for Bdellovibrionaceae and Peredibacteraceae. Phylogenetic analysis suggests that Bdellovibrionaceae are more diverse than Peredibacteraceae and that some OTUs belong to new species of Bdellovibrionaceae. We also found that dominant OTUs were present simultaneously in the two lakes, while some others were specific to each lake, suggesting an adaptive pattern. Finally, both abundance and diversity of BALOs were poorly associated with abiotic factors except temperature, suggesting the importance of studying biotic relationships, assumed to play a greater role than physico-chemical variables in BALOs' dynamics and distribution.
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Affiliation(s)
- Jade A. Ezzedine
- Université Savoie Mont-Blanc, INRAE, CARRTEL, 74200 Thonon les Bains, France
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, CEA, INRAE, IRIG, Université Grenoble Alpes, 38058 Grenoble, France
| | - Mathilde Scheifler
- Sorbonne Université, CNRS, Biologie Intégrative des Organismes Marins, BIOM, Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France
| | - Yves Desdevises
- Sorbonne Université, CNRS, Biologie Intégrative des Organismes Marins, BIOM, Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France
| | - Stéphan Jacquet
- Université Savoie Mont-Blanc, INRAE, CARRTEL, 74200 Thonon les Bains, France
- Correspondence:
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6
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Mookherjee A, Jurkevitch E. Interactions between Bdellovibrio and like organisms and bacteria in biofilms: beyond predator-prey dynamics. Environ Microbiol 2021; 24:998-1011. [PMID: 34816563 DOI: 10.1111/1462-2920.15844] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/03/2021] [Accepted: 11/08/2021] [Indexed: 12/19/2022]
Abstract
Bdellovibrio and like organisms (BALOs) prey on Gram-negative bacteria in the planktonic phase as well as in biofilms, with the ability to reduce prey populations by orders of magnitude. During the last few years, evidence has mounted for a significant ecological role for BALOs, with important implications for our understanding of microbial community dynamics as well as for applications against pathogens, including drug-resistant pathogens, in medicine, agriculture and aquaculture, and in industrial settings for various uses. However, our understanding of biofilm predation by BALOs is still very fragmentary, including gaps in their effect on biofilm structure, on prey resistance, and on evolutionary outcomes of both predators and prey. Furthermore, their impact on biofilms has been shown to reach beyond predation, as they are reported to reduce biofilm structures of non-prey cells (including Gram-positive bacteria). Here, we review the available literature on BALOs in biofilms, extending known aspects to potential mechanisms employed by the predators to grow in biofilms. Within that context, we discuss the potential ecological significance and potential future utilization of the predatory and enzymatic possibilities offered by BALOs in medical, agricultural and environmental applications.
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Affiliation(s)
- Abhirup Mookherjee
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Edouard Jurkevitch
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel
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7
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Novick RP. Antibacterial particles and predatory bacteria as alternatives to antibacterial chemicals in the era of antibiotic resistance. Curr Opin Microbiol 2021; 64:109-116. [PMID: 34688038 DOI: 10.1016/j.mib.2021.09.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 12/26/2022]
Abstract
This review is focused on the subset of antibacterial agents whose action involves one-on-one targeting of infecting bacteria. These agents target individual bacteria and their efficacy is based on particle numbers in contrast to chemical agents such as antibiotics, whose efficacy is based on minimal inhibitory concentrations. Four extant members of this class are predatory bacteria, functional (plaque-forming) phages, and engineered particulate systems, phagemids (plasmids that contain a phage packaging signal) and antibacterial drones (ABDs) that package chromosomal island DNA carrying antibacterial genes. We differentiate the natural predators, phages and predatory bacteria, from the engineered delivery vehicles, phagemids and ABDs, because the latter are much more versatile and can largely bypass the historical warfare that informs the predator-prey interactions.
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8
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Ezzedine JA, Desdevises Y, Jacquet S. Bdellovibrio and like organisms: current understanding and knowledge gaps of the smallest cellular hunters of the microbial world. Crit Rev Microbiol 2021; 48:428-449. [PMID: 34595998 DOI: 10.1080/1040841x.2021.1979464] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Almost sixty years ago, Bdellovibrio and like organisms (BALOs) were discovered as the first obligate bacterial predators of other bacteria known to science. Since then, they were shown to be diverse and ubiquitous in the environment, and to bear astonishing ecological, physiological, and metabolic capabilities. The last decade has seen important strides made in understanding the mechanistic basis of their life cycle, the dynamics of their interactions with prey, along with significant developments towards their use in medicine, agriculture, and industry. This review details these achievements, identify current understanding and knowledge gaps to encourage and guide future BALO research.
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Affiliation(s)
- Jade A Ezzedine
- Université Savoie Mont-Blanc, INRAE, CARRTEL, Thonon-les-Bains, France.,Laboratoire de Physiologie Cellulaire et Végétale, CNRS, CEA, INRAE, IRIG, Université Grenoble Alpes, Grenoble, France
| | - Yves Desdevises
- CNRS, Biologie Intégrative des Organismes Marins, Observatoire Océanologique, Sorbonne Université, Banyuls-sur-Mer, France
| | - Stéphan Jacquet
- Université Savoie Mont-Blanc, INRAE, CARRTEL, Thonon-les-Bains, France
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9
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Hoshiko Y, Nishiyama Y, Moriya T, Kadokami K, López-Jácome LE, Hirano R, García-Contreras R, Maeda T. Quinolone Signals Related to Pseudomonas Quinolone Signal-Quorum Sensing Inhibits the Predatory Activity of Bdellovibrio bacteriovorus. Front Microbiol 2021; 12:722579. [PMID: 34566925 PMCID: PMC8461301 DOI: 10.3389/fmicb.2021.722579] [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: 06/09/2021] [Accepted: 08/12/2021] [Indexed: 12/12/2022] Open
Abstract
Bdellovibrio bacteriovorus is one of the predatory bacteria; therefore, it can act as a novel “living antibiotic,” unlike the current antibiotics. Here the predation of Escherichia coli by B. bacteriovorus was inhibited in the presence of Pseudomonas aeruginosa. This study investigated whether P. aeruginosa-induced predation inhibition is associated with bacterial quorum sensing (QS). Each las, rhl, or pqs QS mutant in P. aeruginosa was used to check the predatory activity of E. coli cells using B. bacteriovorus. As a result, the predatory activity of B. bacteriovorus increased in a mutant pqs QS system, whereas wild-type PA14 inhibited the predatory activity. Moreover, the addition of 4-hydroxy-2-heptylquinoline (HHQ) or the analog triggered the low predatory activity of B. bacteriovorus and killed B. bacteriovorus cells. Therefore, a defensive action of P. aeruginosa against B. bacteriovorus is activated by the pqs QS system, which produces some quinolone compounds such as HHQ.
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Affiliation(s)
- Yuki Hoshiko
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Japan
| | - Yoshito Nishiyama
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Japan
| | - Tae Moriya
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Japan
| | - Kiwao Kadokami
- Institute of Environmental Science and Technology, The University of Kitakyushu, Kitakyushu, Japan
| | - Luis Esaú López-Jácome
- Department of Microbiology and Parasitology, Faculty of Medicine, UNAM, Mexico City, Mexico.,Laboratory of Infectology, National Institute of Rehabilitation Luis Guillermo Ibarra Ibarra, Mexico City, Mexico
| | - Ryutaro Hirano
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Japan
| | | | - Toshinari Maeda
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Japan
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10
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Cohen Y, Pasternak Z, Müller S, Hübschmann T, Schattenberg F, Sivakala KK, Abed-Rabbo A, Chatzinotas A, Jurkevitch E. Community and single cell analyses reveal complex predatory interactions between bacteria in high diversity systems. Nat Commun 2021; 12:5481. [PMID: 34531395 PMCID: PMC8446003 DOI: 10.1038/s41467-021-25824-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/25/2021] [Indexed: 02/08/2023] Open
Abstract
A fundamental question in community ecology is the role of predator-prey interactions in food-web stability and species coexistence. Although microbial microcosms offer powerful systems to investigate it, interrogating the environment is much more arduous. Here, we show in a 1-year survey that the obligate predators Bdellovibrio and like organisms (BALOs) can regulate prey populations, possibly in a density-dependent manner, in the naturally complex, species-rich environments of wastewater treatment plants. Abundant as well as rarer prey populations are affected, leading to an oscillating predatory landscape shifting at various temporal scales in which the total population remains stable. Shifts, along with differential prey range, explain co-existence of the numerous predators through niche partitioning. We validate these sequence-based findings using single-cell sorting combined with fluorescent hybridization and community sequencing. Our approach should be applicable for deciphering community interactions in other systems.
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Affiliation(s)
- Yossi Cohen
- Department of Plant Pathology and Microbiology, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Zohar Pasternak
- Department of Plant Pathology and Microbiology, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
- Division of Identification and Forensic Science, Israel Police, National Headquarters, Jerusalem, Israel
| | - Susann Müller
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Thomas Hübschmann
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Florian Schattenberg
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Kunjukrishnan Kamalakshi Sivakala
- Department of Plant Pathology and Microbiology, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | | | - Antonis Chatzinotas
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
- Institute of Biology, Leipzig University, Talstrasse 33, 04103, Leipzig, Germany
- Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany
| | - Edouard Jurkevitch
- Department of Plant Pathology and Microbiology, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel.
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11
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Aharon E, Mookherjee A, Pérez-Montaño F, Mateus da Silva G, Sathyamoorthy R, Burdman S, Jurkevitch E. Secretion systems play a critical role in resistance to predation by Bdellovibrio bacteriovorus. Res Microbiol 2021; 172:103878. [PMID: 34492337 DOI: 10.1016/j.resmic.2021.103878] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 08/02/2021] [Accepted: 08/07/2021] [Indexed: 11/28/2022]
Abstract
Bdellovibrio bacteriovorus, a Gram-negative predatory bacterium belonging to the Bdellovibrio and like organisms (BALOs), predate on Gram-negative bacteria. BALO strains differ in prey range but so far, the genetic basis of resistance against BALO predation is hardly understood. We developed a loss-of-function approach to screen for sensitive mutants in a library of strain M6, a predation-resistant strain of the plant pathogen Acidovorax citrulli. The screen is based on tracking the growth of a B. bacteriovorus strain expressing the fluorescent reporter Tdtomato in mutant pools to reveal predation-sensitive variants. Two independent loci were identified in mutant strains exhibiting significant levels of susceptibility to the predator. Genes in the two loci were analysed using both protein sequence homology and protein structure modeling. Both were secretion-related proteins and thus associated to the bacterial cell wall. Successful complementation of gspK, a gene encoding for a minor pseudopilin protein confirmed the involvement of the type II secretion system in A. citrulli M6 resistance. This proof of concept study shows that our approach can identify key elements of the BALO-prey interaction, and it validates the hypothesis that mutational changes in a single gene can drastically impact prey resistance to BALO predation.
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Affiliation(s)
- Einav Aharon
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
| | - Abhirup Mookherjee
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
| | - Francisco Pérez-Montaño
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel; Department of Microbiology, University of Seville, Seville, Spain.
| | - Gustavo Mateus da Silva
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
| | - Rajesh Sathyamoorthy
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
| | - Saul Burdman
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
| | - Edouard Jurkevitch
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Institute of Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
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12
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Cavallo FM, Jordana L, Friedrich AW, Glasner C, van Dijl JM. Bdellovibrio bacteriovorus: a potential 'living antibiotic' to control bacterial pathogens. Crit Rev Microbiol 2021; 47:630-646. [PMID: 33934682 DOI: 10.1080/1040841x.2021.1908956] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Bdellovibrio bacteriovorus is a small Deltaproteobacterium which, since its discovery, has distinguished itself for the unique ability to prey on other Gram-negative bacteria. The studies on this particular "predatory bacterium", have gained momentum in response to the rising problem of antibiotic resistance, because it could be applied as a potential probiotic and antibiotic agent. Hereby, we present recent advances in the study of B. bacteriovorus, comprehending fundamental aspects of its biology, obligatory intracellular life cycle, predation resistance, and potential applications. Furthermore, we discuss studies that pave the road towards the use of B. bacteriovorus as a "living antibiotic" in human therapy, focussing on its interaction with biofilms, the host immune response, predation susceptibility and in vivo application models. The available data imply that it will be possible to upgrade this predator bacterium from a predominantly academic interest to an instrument that could confront antibiotic resistant infections.
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Affiliation(s)
- Francis M Cavallo
- Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Lorea Jordana
- Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Alexander W Friedrich
- Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Corinna Glasner
- Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jan Maarten van Dijl
- Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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13
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Choi SY, Lim S, Yoon KH, Lee JI, Mitchell RJ. Biotechnological Activities and Applications of Bacterial Pigments Violacein and Prodigiosin. J Biol Eng 2021; 15:10. [PMID: 33706806 PMCID: PMC7948353 DOI: 10.1186/s13036-021-00262-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/03/2021] [Indexed: 12/14/2022] Open
Abstract
In this review, we discuss violacein and prodigiosin, two chromogenic bacterial secondary metabolites that have diverse biological activities. Although both compounds were "discovered" more than seven decades ago, interest into their biological applications has grown in the last two decades, particularly driven by their antimicrobial and anticancer properties. These topics will be discussed in the first half of this review. The latter half delves into the current efforts of groups to produce these two compounds. This includes in both their native bacterial hosts and heterogeneously in other bacterial hosts, including discussing some of the caveats related to the yields reported in the literature, and some of the synthetic biology techniques employed in this pursuit.
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Affiliation(s)
- Seong Yeol Choi
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Sungbin Lim
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Kyoung-Hye Yoon
- Department of Physiology, Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Gangwon-do, South Korea.
| | - Jin I Lee
- Division of Biological Science and Technology, College of Science and Technology, Yonsei University, Mirae Campus, Wonju, Gangwon-do, South Korea.
| | - Robert J Mitchell
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea.
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14
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Dwidar M, Jang H, Sangwan N, Mun W, Im H, Yoon S, Choi S, Nam D, Mitchell RJ. Diffusible Signaling Factor, a Quorum-Sensing Molecule, Interferes with and Is Toxic Towards Bdellovibrio bacteriovorus 109J. MICROBIAL ECOLOGY 2021; 81:347-356. [PMID: 32892232 DOI: 10.1007/s00248-020-01585-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
Bdellovibrio bacteriovorus 109J is a predatory bacterium which lives by predating on other Gram-negative bacteria to obtain the nutrients it needs for replication and survival. Here, we evaluated the effects two classes of bacterial signaling molecules (acyl homoserine lactones (AHLs) and diffusible signaling factor (DSF)) have on B. bacteriovorus 109J behavior and viability. While AHLs had a non-significant impact on predation rates, DSF considerably delayed predation and bdelloplast lysis. Subsequent experiments showed that 50 μM DSF also reduced the motility of attack-phase B. bacteriovorus 109J cells by 50% (38.2 ± 14.9 vs. 17 ± 8.9 μm/s). Transcriptomic analyses found that DSF caused genome-wide changes in B. bacteriovorus 109J gene expression patterns during both the attack and intraperiplasmic phases, including the significant downregulation of the flagellum assembly genes and numerous serine protease genes. While the former accounts for the reduced speeds observed, the latter was confirmed experimentally with 50 μM DSF completely blocking protease secretion from attack-phase cells. Additional experiments found that 30% of the total cellular ATP was released into the supernatant when B. bacteriovorus 109J was exposed to 200 μM DSF, implying that this QS molecule negatively impacts membrane integrity.
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Affiliation(s)
- Mohammed Dwidar
- Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, 44195, USA.
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA.
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA.
| | - Hyochan Jang
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Naseer Sangwan
- Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, 44195, USA
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Wonsik Mun
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Hansol Im
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Sora Yoon
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Sooin Choi
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Dougu Nam
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea.
| | - Robert J Mitchell
- School of Life Sciences, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea.
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15
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Williams HN, Chen H. Environmental Regulation of the Distribution and Ecology of Bdellovibrio and Like Organisms. Front Microbiol 2020; 11:545070. [PMID: 33193128 PMCID: PMC7658600 DOI: 10.3389/fmicb.2020.545070] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 10/05/2020] [Indexed: 12/21/2022] Open
Abstract
The impact of key environmental factors, salinity, prey, and temperature, on the survival and ecology of Bdellovibrio and like bacteria (BALOs), including the freshwater/terrestrial, non-halotolerant group and the halophilic Halobacteriovorax strains, has been assessed based on a review of data in the literature. These topics have been studied by numerous investigators for nearly six decades now, and much valuable information has been amassed and reported. The collective data shows that salinity, prey, and temperature play a major role in, not only the growth and survival of BALOs, but also the structure and composition of BALO communities and the distribution of the predators. Salinity is a major determinant in the selection of BALO habitats, distribution, prey bacteria, and systematics. Halophilic BALOs require salt for cellular functions and are found only in saltwater habitats, and prey primarily on saltwater bacteria. To the contrary, freshwater/terrestrial BALOs are non-halotolerant and inhibited by salt concentrations greater than 0.5%, and are restricted to freshwater, soils, and other low salt environments. They prey preferentially on bacteria in the same habitats. The halophilic BALOs are further separated on the basis of their tolerance to various salt concentrations. Some strains are found in low salt environments and others in high salt regions. In situ studies have demonstrated that salinity gradients in estuarine systems govern the type of BALO communities that will persist within a specific gradient. Bacterial prey for BALOs functions more than just being a substrate for the predators and include the potential for different prey species to structure the BALO community at the phylotype level. The pattern of susceptibility or resistance of various bacteria species has been used almost universally to differentiate strains of new BALO isolates. However, the method suffers from a lack of uniformity among different laboratories. The use of molecular methods such as comparative analysis of the 16S rDNA gene and metagenomics have provided more specific approaches to distinguished between isolates. Differences in temperature growth range among different BALO groups and strains have been demonstrated in many laboratory experiments. The temperature optima and growth range for the saltwater BALOs is typically lower than that of the freshwater/terrestrial BALOs. The collective data shows not only that environmental factors have a great impact on BALO ecology, but also how the various factors affect BALO populations in nature.
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Affiliation(s)
- Henry N Williams
- School of the Environment, Florida Agricultural and Mechanical University, Tallahassee, FL, United States
| | - Huan Chen
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, United States
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16
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Mitchell RJ, Mun W, Mabekou SS, Jang H, Choi SY. Compounds affecting predation by and viability of predatory bacteria. Appl Microbiol Biotechnol 2020; 104:3705-3713. [DOI: 10.1007/s00253-020-10530-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/01/2020] [Accepted: 03/05/2020] [Indexed: 12/13/2022]
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17
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Cattoir V, Felden B. Future Antibacterial Strategies: From Basic Concepts to Clinical Challenges. J Infect Dis 2020; 220:350-360. [PMID: 30893436 DOI: 10.1093/infdis/jiz134] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Accepted: 03/19/2019] [Indexed: 11/12/2022] Open
Abstract
This review presents potential benefits and limitations of innovative strategies that are currently investigated for the discovery of novel antibacterial agents to prevent or treat infections caused by multidrug-resistant organisms.
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Affiliation(s)
- Vincent Cattoir
- Bacterial Regulatory RNAs and Medicine, Inserm UMR_S 1230, University of Rennes 1, France.,Department of Clinical Microbiology, Rennes University Hospital, France.,National Reference Center for Antimicrobial Resistance, Rennes, France
| | - Brice Felden
- Bacterial Regulatory RNAs and Medicine, Inserm UMR_S 1230, University of Rennes 1, France
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18
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Im H, Kwon H, Cho G, Kwon J, Choi SY, Mitchell RJ. Viscosity has dichotomous effects on Bdellovibrio bacteriovorus HD100 predation. Environ Microbiol 2019; 21:4675-4684. [PMID: 31498968 DOI: 10.1111/1462-2920.14799] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 09/05/2019] [Indexed: 11/28/2022]
Abstract
Bdellovibrio bacteriovorus HD100 is a highly motile predatory bacterium that consumes other Gram-negative bacteria for its sustenance. Here, we describe the impacts the media viscosity has both on the motility of predator and its attack rates. Experiments performed in polyethylene glycol (PEG) solutions, a linear polymer, found a viscosity of 10 mPa s (5% PEG) negatively impacted predation over a 24-h period. When the viscosity was increased to 27 mPa s (10% PEG), predation was nearly abolished. Tests with three other B. bacteriovorus strains, i.e., 109J and two natural isolates, found identical results. Short-term (2-h) experiments, however, found attack rates were improved in 1% PEG, which had a viscosity of 5.4 mPa s, using bioluminescent prey and their viabilities. In contrast, when experiments were performed in dextran, a branched polymer, no increase in predation was seen even though the viscosity was a comparable 5.1 mPa s. The enhanced attack rates in this solution coincided with a 31% increase in B. bacteriovorus HD100 swimming speeds (62 μm s-1 in 1% PEG vs. 47.5 μm s-1 in HEPES-salt).
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Affiliation(s)
- Hansol Im
- Division of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Heeun Kwon
- Division of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Gayoung Cho
- Division of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Jisoo Kwon
- Division of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Seong Yeol Choi
- Division of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Robert J Mitchell
- Division of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
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19
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Cho G, Kwon J, Soh SM, Jang H, Mitchell RJ. Sensitivity of predatory bacteria to different surfactants and their application to check bacterial predation. Appl Microbiol Biotechnol 2019; 103:8169-8178. [PMID: 31407038 DOI: 10.1007/s00253-019-10069-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 12/27/2022]
Abstract
We evaluated the toxicity of surfactants against different predatory bacteria. Tests with Bdellovibrio bacteriovorus HD100 and SDS, an anionic surfactant, showed the predator was very sensitive; 0.02% SDS completely killed the predatory population (7-log loss; < 10 PFU/ml remaining) both when free-swimming or within the bdelloplast, i.e., intraperiplasmic. Similar results were also observed with B. bacteriovorus 109J and Peredibacter starrii. In contrast, none of the prey (E. coli, Klebsiella pneumoniae, Acinetobacter baumannii, or Pseudomonas sp. DSM 50906) viabilities were negatively affected by SDS. Triton X-100, a nonionic surfactant, was slightly less toxic towards B. bacteriovorus HD100 (viability loss of only 4-log), while two cationic surfactants, i.e., benzalkonium chloride (BZC) and cetyltrimethylammonium bromide (CTAB), were toxic towards both the predator and prey. Based on the above findings, we tested the potential use of SDS as a means to control predation. Addition of 0.02% SDS immediately halted predation based upon the prey bioluminescence, which leveled off and remained steady. This was confirmed using the predator viabilities; no predators were found in any of the samples where SDS was added. Consequently, low concentrations of SDS can be used as a simple means to control B. bacteriovorus HD100 activities.
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Affiliation(s)
- Gayoung Cho
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Jisoo Kwon
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Sandrine Mabekou Soh
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Hyochan Jang
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Robert J Mitchell
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea.
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Abstract
Bdellovibrio bacteriovorus is a predatory bacterium that can kill a wide range of Gram-negative bacteria, including many human pathogens. Given the global rise of antibiotic resistance and dearth of new antibiotics discovered in the past 30 years, this predator has potential as an alternative to traditional antibiotics. For many years, B. bacteriovorus research was hampered by a lack of genetic tools, and the genetic mechanisms of predation have only recently begun to be established. Here, we comprehensively identify and characterize predator genes required for killing bacterial prey, as well as genes that interfere in this process, which may allow us to design better therapeutic predators. Based on our study, we and other researchers may ultimately be able to genetically engineer strains that have improved killing rates, target specific species of prey, or preferentially target prey in the planktonic or biofilm state. Bdellovibrio bacteriovorus is a bacterial predator capable of killing and replicating inside most Gram-negative bacteria, including antibiotic-resistant pathogens. Despite growing interest in this organism as a potential therapeutic, many of its genes remain uncharacterized. Here, we perform a high-throughput genetic screen with B. bacteriovorus using transposon sequencing (Tn-seq) to explore the genetic requirements of predation. Two hundred one genes were deemed essential for growth in the absence of prey, whereas over 100 genes were found to be specifically required for predative growth on the human pathogens Vibrio cholerae and Escherichia coli in both planktonic and biofilm states. To further this work, we created an ordered-knockout library in B. bacteriovorus and developed new high-throughput techniques to characterize the mutants by their stage of deficiency in the predator life cycle. Using microscopy and flow cytometry, we confirmed 10 mutants defective in prey attachment and eight mutants defective in prey rounding. The majority of these genes are hypothetical and previously uncharacterized. Finally, we propose new nomenclature to group B. bacteriovorus mutants into classes based on their stage of predation defect. These results contribute to our basic understanding of bacterial predation and may be useful for harnessing B. bacteriovorus to kill harmful pathogens in the clinical setting.
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Vibrio cholerae motility exerts drag force to impede attack by the bacterial predator Bdellovibrio bacteriovorus. Nat Commun 2018; 9:4757. [PMID: 30420597 PMCID: PMC6232129 DOI: 10.1038/s41467-018-07245-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 10/18/2018] [Indexed: 12/21/2022] Open
Abstract
The bacterial predator Bdellovibrio bacteriovorus is evolved to attack and kill other bacteria, including the human intestinal pathogen Vibrio cholerae. Although B. bacteriovorus exhibit a broad prey range, little is known about the genetic determinants of prey resistance and sensitivity. Here we perform a genetic screen on V. cholerae and identify five pathways contributing to predation susceptibility. We find that the essential virulence regulators ToxR/S increase susceptibility to predation, as mutants of these genes are more resistant to predation. We observe by flow cytometry that lipopolysaccharide is a critical defense, as mutants lacking O-antigen are rapidly attacked by predatory B. bacteriovorus. Using polymer solutions to alter media viscosity, we find that when B. bacteriovorus attacks motile V. cholerae, increased drag forces slow its ability to prey. These results provide insights into key prey resistance mechanisms, and may be useful in the application of B. bacteriovorus in treating infections. Prey bacteria have evolved different strategies to counteract predation but the genetic basis remains unclear. Here, Duncan et al. identify key genes involved in Vibrio cholerae sensitivity to Bdellovibrio bacteriovorus predation, providing new insights into prey resistance mechanisms.
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