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Hu WF, Yang JY, Wang JJ, Yuan SF, Yue XJ, Zhang Z, Zhang YQ, Meng JY, Li YZ. Characteristics and immune functions of the endogenous CRISPR-Cas systems in myxobacteria. mSystems 2024; 9:e0121023. [PMID: 38747603 DOI: 10.1128/msystems.01210-23] [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: 11/13/2023] [Accepted: 04/15/2024] [Indexed: 06/19/2024] Open
Abstract
The clustered regularly interspaced short palindromic repeats and their associated proteins (CRISPR-Cas) system widely occurs in prokaryotic organisms to recognize and destruct genetic invaders. Systematic collation and characterization of endogenous CRISPR-Cas systems are conducive to our understanding and potential utilization of this natural genetic machinery. In this study, we screened 39 complete and 692 incomplete genomes of myxobacteria using a combined strategy to dispose of the abridged genome information and revealed at least 19 CRISPR-Cas subtypes, which were distributed with a taxonomic difference and often lost stochastically in intraspecies strains. The cas genes in each subtype were evolutionarily clustered but deeply separated, while most of the CRISPRs were divided into four types based on the motif characteristics of repeat sequences. The spacers recorded in myxobacterial CRISPRs were in high G+C content, matching lots of phages, tiny amounts of plasmids, and, surprisingly, massive organismic genomes. We experimentally demonstrated the immune and self-target immune activities of three endogenous systems in Myxococcus xanthus DK1622 against artificial genetic invaders and revealed the microhomology-mediated end-joining mechanism for the immunity-induced DNA repair but not homology-directed repair. The panoramic view and immune activities imply potential omnipotent immune functions and applications of the endogenous CRISPR-Cas machinery. IMPORTANCE Serving as an adaptive immune system, clustered regularly interspaced short palindromic repeats and their associated proteins (CRISPR-Cas) empower prokaryotes to fend off the intrusion of external genetic materials. Myxobacteria are a collective of swarming Gram-stain-negative predatory bacteria distinguished by intricate multicellular social behavior. An in-depth analysis of their intrinsic CRISPR-Cas systems is beneficial for our understanding of the survival strategies employed by host cells within their environmental niches. Moreover, the experimental findings presented in this study not only suggest the robust immune functions of CRISPR-Cas in myxobacteria but also their potential applications.
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Affiliation(s)
- Wei-Feng Hu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Jiang-Yu Yang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Jing-Jing Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Shu-Fei Yuan
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Xin-Jing Yue
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Zheng Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Ya-Qi Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Jun-Yan Meng
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Yue-Zhong Li
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
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Contreras-Moreno FJ, Pérez J, Muñoz-Dorado J, Moraleda-Muñoz A, Marcos-Torres FJ. Myxococcus xanthus predation: an updated overview. Front Microbiol 2024; 15:1339696. [PMID: 38328431 PMCID: PMC10849154 DOI: 10.3389/fmicb.2024.1339696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/15/2024] [Indexed: 02/09/2024] Open
Abstract
Bacterial predators are widely distributed across a variety of natural environments. Understanding predatory interactions is of great importance since they play a defining role in shaping microbial communities in habitats such as soils. Myxococcus xanthus is a soil-dwelling bacterial predator that can prey on Gram-positive and Gram-negative bacteria and even on eukaryotic microorganisms. This model organism has been studied for many decades for its unusual lifecycle, characterized by the formation of multicellular fruiting bodies filled with myxospores. However, less is known about its predatory behavior despite being an integral part of its lifecycle. Predation in M. xanthus is a multifactorial process that involves several mechanisms working synergistically, including motility systems to efficiently track and hunt prey, and a combination of short-range and contact-dependent mechanisms to achieve prey death and feed on them. In the short-range attack, M. xanthus is best known for the collective production of secondary metabolites and hydrolytic enzymes to kill prey and degrade cellular components. On the other hand, contact-dependent killing is a cell-to-cell process that relies on Tad-like and type III secretion systems. Furthermore, recent research has revealed that metals also play an important role during predation, either by inducing oxidative stress in the prey, or by competing for essential metals. In this paper, we review the current knowledge about M. xanthus predation, focusing on the different mechanisms used to hunt, kill, and feed on its prey, considering the most recent discoveries and the transcriptomic data available.
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Affiliation(s)
| | | | | | - Aurelio Moraleda-Muñoz
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Granada, Spain
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Müller S, DeLeon O, Atkinson SN, Saravia F, Kellogg S, Shank EA, Kirby JR. Thiocillin contributes to the ecological fitness of Bacillus cereus ATCC 14579 during interspecies interactions with Myxococcus xanthus. Front Microbiol 2023; 14:1295262. [PMID: 38075900 PMCID: PMC10704990 DOI: 10.3389/fmicb.2023.1295262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 11/09/2023] [Indexed: 02/12/2024] Open
Abstract
The soil-dwelling delta-proteobacterium Myxococcus xanthus is a model organism to study predation and competition. M. xanthus preys on a broad range of bacteria mediated by lytic enzymes, exopolysaccharides, Type-IV pilus-based motility, and specialized metabolites. Competition between M. xanthus and prey bacterial strains with various specialized metabolite profiles indicates a range of fitness, suggesting that specialized metabolites contribute to prey survival. To expand our understanding of how specialized metabolites affect predator-prey dynamics, we assessed interspecies interactions between M. xanthus and two strains of Bacillus cereus. While strain ATCC 14579 resisted predation, strain T was found to be highly sensitive to M. xanthus predation. The interaction between B. cereus ATCC 14579 and M. xanthus appears to be competitive, resulting in population loss for both predator and prey. Genome analysis revealed that ATCC 14579 belongs to a clade that possesses the biosynthetic gene cluster for production of thiocillins, whereas B. cereus strain T lacks those genes. Further, purified thiocillin protects B. cereus strains unable to produce this specialized metabolite, strengthening the finding that thiocillin protects against predation and contributes to the ecological fitness of B. cereus ATCC 14579. Lastly, strains that produce thiocillin appear to confer some level of protection to their own antibiotic by encoding an additional copy of the L11 ribosomal protein, a known target for thiopeptides. This work highlights the importance of specialized metabolites affecting predator-prey dynamics in soil microenvironments.
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Affiliation(s)
- Susanne Müller
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Orlando DeLeon
- Department of Medicine, University of Chicago Pritzker School of Medicine, Chicago, IL, United States
| | - Samantha N. Atkinson
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Fatima Saravia
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Stephanie Kellogg
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Elizabeth A. Shank
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worchester, MA, United States
| | - John R. Kirby
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
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Santamaría RI, Martínez-Carrasco A, Tormo JR, Martín J, Genilloud O, Reyes F, Díaz M. Interactions of Different Streptomyces Species and Myxococcus xanthus Affect Myxococcus Development and Induce the Production of DK-Xanthenes. Int J Mol Sci 2023; 24:15659. [PMID: 37958645 PMCID: PMC10649082 DOI: 10.3390/ijms242115659] [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: 09/19/2023] [Revised: 10/19/2023] [Accepted: 10/24/2023] [Indexed: 11/15/2023] Open
Abstract
The co-culturing of microorganisms is a well-known strategy to study microbial interactions in the laboratory. This approach facilitates the identification of new signals and molecules produced by one species that affects other species' behavior. In this work, we have studied the effects of the interaction of nine Streptomyces species (S. albidoflavus, S. ambofaciens, S. argillaceus, S. griseus, S. lividans, S. olivaceus, S. parvulus, S. peucetius, and S. rochei) with the predator bacteria Myxococcus xanthus, five of which (S. albidoflavus, S. griseus, S. lividans, S. olivaceus, and S. argillaceus) induce mound formation of M. xanthus on complex media (Casitone Yeast extract (CYE) and Casitone tris (CTT); media on which M. xanthus does not form these aggregates under normal culture conditions. An in-depth study on S. griseus-M. xanthus interactions (the Streptomyces strain producing the strongest effect) has allowed the identification of two siderophores produced by S. griseus, demethylenenocardamine and nocardamine, responsible for this grouping effect over M. xanthus. Experiments using pure commercial nocardamine and different concentrations of FeSO4 show that iron depletion is responsible for the behavior of M. xanthus. Additionally, it was found that molecules, smaller than 3 kDa, produced by S. peucetius can induce the production of DK-xanthenes by M. xanthus.
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Affiliation(s)
- Ramón I. Santamaría
- Instituto de Biología Funcional y Genómica (IBFG), Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, C/Zacarías González, nº 2, 37007 Salamanca, Spain;
| | - Ana Martínez-Carrasco
- Instituto de Biología Funcional y Genómica (IBFG), Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, C/Zacarías González, nº 2, 37007 Salamanca, Spain;
| | - José R. Tormo
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Avda. del Conocimiento 34, 18016 Granada, Spain; (J.R.T.); (J.M.); (O.G.); (F.R.)
| | - Jesús Martín
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Avda. del Conocimiento 34, 18016 Granada, Spain; (J.R.T.); (J.M.); (O.G.); (F.R.)
| | - Olga Genilloud
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Avda. del Conocimiento 34, 18016 Granada, Spain; (J.R.T.); (J.M.); (O.G.); (F.R.)
| | - Fernando Reyes
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Avda. del Conocimiento 34, 18016 Granada, Spain; (J.R.T.); (J.M.); (O.G.); (F.R.)
| | - Margarita Díaz
- Instituto de Biología Funcional y Genómica (IBFG), Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, C/Zacarías González, nº 2, 37007 Salamanca, Spain;
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Ahearne A, Phillips KE, Knehans T, Hoing M, Dowd SE, Stevens DC. Chromosomal organization of biosynthetic gene clusters, including those of nine novel species, suggests plasticity of myxobacterial specialized metabolism. Front Microbiol 2023; 14:1227206. [PMID: 37601375 PMCID: PMC10435759 DOI: 10.3389/fmicb.2023.1227206] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/11/2023] [Indexed: 08/22/2023] Open
Abstract
Introduction Natural products discovered from bacteria provide critically needed therapeutic leads for drug discovery, and myxobacteria are an established source for metabolites with unique chemical scaffolds and biological activities. Myxobacterial genomes accommodate an exceptional number and variety of biosynthetic gene clusters (BGCs) which encode for features involved in specialized metabolism. Methods In this study, we describe the collection, sequencing, and genome mining of 20 myxobacteria isolated from rhizospheric soil samples collected in North America. Results Nine isolates were determined to be novel species of myxobacteria including representatives from the genera Archangium, Myxococcus, Nannocystis, Polyangium, Pyxidicoccus, Sorangium, and Stigmatella. Growth profiles, biochemical assays, and descriptions were provided for all proposed novel species. We assess the BGC content of all isolates and observe differences between Myxococcia and Polyangiia clusters. Discussion Continued discovery and sequencing of novel myxobacteria from the environment provide BGCs for the genome mining pipeline. Utilizing complete or near-complete genome sequences, we compare the chromosomal organization of BGCs of related myxobacteria from various genera and suggest that the spatial proximity of hybrid, modular clusters contributes to the metabolic adaptability of myxobacteria.
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Affiliation(s)
- Andrew Ahearne
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Kayleigh E. Phillips
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Thomas Knehans
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Miranda Hoing
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Scot E. Dowd
- Molecular Research LP (MR DNA), Shallowater, TX, United States
| | - David Cole Stevens
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS, United States
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Kaimer C, Weltzer ML, Wall D. Two reasons to kill: predation and kin discrimination in myxobacteria. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001372. [PMID: 37494115 PMCID: PMC10433427 DOI: 10.1099/mic.0.001372] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Accepted: 07/15/2023] [Indexed: 07/27/2023]
Abstract
Myxobacteria are social microbial predators that use cell-cell contacts to identify bacterial or fungal prey and to differentiate kin relatives to initiate cellular responses. For prey killing, they assemble Tad-like and type III-like secretion systems at contact sites. For kin discrimination (KD), they assemble outer membrane exchange complexes composed of the TraA and TraB receptors at contacts sites. A type VI secretion system and Rhs proteins also mediate KD. Following cellular recognition, these systems deliver appropriate effectors into target cells. For prey, this leads to cell death and lysis for nutrient consumption by myxobacteria. In KD, a panel of effectors are delivered, and if adjacent cells are clonal cells, resistance ensues because they express a cognate panel of immunity factors; while nonkin lack complete immunity and are intoxicated. This review compares and contrasts recent findings from these systems in myxobacteria.
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Affiliation(s)
- Christine Kaimer
- Department of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Michael L. Weltzer
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
| | - Daniel Wall
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
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7
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Yu U, Kim J, Park S, Cho K. Tubulysins are Essential for the Preying of Ciliates by Myxobacteria. J Microbiol 2023:10.1007/s12275-023-00056-2. [PMID: 37314675 DOI: 10.1007/s12275-023-00056-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 05/08/2023] [Accepted: 05/11/2023] [Indexed: 06/15/2023]
Abstract
Tubulysins are bioactive secondary metabolites produced by myxobacteria that promote microtubule disassembly. Microtubules are required for protozoa such as Tetrahymena to form cilia and flagella. To study the role of tubulysins in myxobacteria, we co-cultured myxobacteria and Tetrahymena. When 4000 Tetrahymena thermophila and 5.0 × 108 myxobacteria were added to 1 ml of CYSE medium and co-cultured for 48 h, the population of T. thermophila increased to more than 75,000. However, co-culturing tubulysin-producing myxobacteria, including Archangium gephyra KYC5002, with T. thermophila caused the population of T. thermophila to decrease from 4000 to less than 83 within 48 h. Almost no dead bodies of T. thermophila were observed in the culture medium. Co-culturing of T. thermophila and the A. gephyra KYC5002 strain with inactivation of the tubulysin biosynthesis gene led to the population of T. thermophila increasing to 46,667. These results show that in nature, most myxobacteria are preyed upon by T. thermophila, but some myxobacteria prey on and kill T. thermophila using tubulysins. Adding purified tubulysin A to T. thermophila changed the cell shape from ovoid to spherical and caused cell surface cilia to disappear.
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Affiliation(s)
- Uisang Yu
- Department of Biotechnology, Hoseo University, Asan, 31499, Republic of Korea
| | - Jiha Kim
- Department of Biotechnology, Hoseo University, Asan, 31499, Republic of Korea
| | - Seohui Park
- Department of Biotechnology, Hoseo University, Asan, 31499, Republic of Korea
| | - Kyungyun Cho
- Department of Biotechnology, Hoseo University, Asan, 31499, Republic of Korea.
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8
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Ahearne A, Phillips K, Knehans T, Hoing M, Dowd SE, Stevens DC. Chromosomal organization of biosynthetic gene clusters suggests plasticity of myxobacterial specialized metabolism including descriptions for nine novel species: Archangium lansinium sp. nov., Myxococcus landrumus sp. nov., Nannocystis bainbridgea sp. nov., Nannocystis poenicansa sp. nov., Nannocystis radixulma sp. nov., Polyangium mundeleinium sp. nov., Pyxidicoccus parkwaysis sp. nov., Sorangium aterium sp. nov., Stigmatella ashevillena sp. nov. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.08.531766. [PMID: 36945379 PMCID: PMC10028903 DOI: 10.1101/2023.03.08.531766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Natural products discovered from bacteria provide critically needed therapeutic leads for drug discovery, and myxobacteria are an established source for metabolites with unique chemical scaffolds and biological activities. Myxobacterial genomes accommodate an exceptional number and variety of biosynthetic gene clusters (BGCs) which encode for features involved in specialized metabolism. Continued discovery and sequencing of novel myxobacteria from the environment provides BGCs for the genome mining pipeline. Herein, we describe the collection, sequencing, and genome mining of 20 myxobacteria isolated from rhizospheric soil samples collected in North America. Nine isolates where determined to be novel species of myxobacteria including representatives from the genera Archangium, Myxococcus, Nannocystis, Polyangium, Pyxidicoccus, Sorangium, and Stigmatella. Growth profiles, biochemical assays, and descriptions are provided for all proposed novel species. We assess the BGC content of all isolates and observe differences between Myxococcia and Polyangiia clusters. Utilizing complete or near complete genome sequences we compare the chromosomal organization of BGCs of related myxobacteria from various genera and suggest spatial proximity of hybrid, modular clusters contributes to the metabolic adaptability of myxobacteria.
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Affiliation(s)
- Andrew Ahearne
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS 38677, USA
| | - Kayleigh Phillips
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS 38677, USA
| | - Thomas Knehans
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS 38677, USA
| | - Miranda Hoing
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS 38677, USA
| | - Scot E. Dowd
- MR DNA, Molecular Research LP, Shallowater, TX 79363, USA
| | - D. Cole Stevens
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS 38677, USA
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Wang C, Xiao Y, Wang Y, Liu Y, Yao Q, Zhu H. Comparative genomics and transcriptomics insight into myxobacterial metabolism potentials and multiple predatory strategies. Front Microbiol 2023; 14:1146523. [PMID: 37213496 PMCID: PMC10196010 DOI: 10.3389/fmicb.2023.1146523] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/19/2023] [Indexed: 05/23/2023] Open
Abstract
Myxobacteria are part of the phylum Myxococcota, encompassing four orders. Most of them display complex lifestyles and broad predation profiles. However, metabolic potential and predation mechanisms of different myxobacteria remains poorly understood. Herein, we used comparative genomics and transcriptomics to analyze metabolic potentials and differentially expressed gene (DEG) profiles of Myxococcus xanthus monoculture (Mx) compared to coculture with Escherichia coli (MxE) and Micrococcus luteus (MxM) prey. The results showed that myxobacteria had conspicuous metabolic deficiencies, various protein secretion systems (PSSs) and the common type II secretion system (T2SS). RNA-seq data demonstrated that M. xanthus overexpressed the potential predation DEGs, particularly those encoding T2SS, the tight adherence (Tad) pilus, different secondary metabolites (myxochelin A/B, myxoprincomide, myxovirescin A1, geosmin and myxalamide), glycosyl transferases and peptidase during predation. Furthermore, the myxalamide biosynthesis gene clusters, two hypothetical gene clusters and one arginine biosynthesis clusters were highly differential expressed in MxE versus MxM. Additionally, homologue proteins of the Tad (kil) system and five secondary metabolites were in different obligate or facultative predators. Finally, we provided a working model for exhibiting multiple predatory strategies when M. xanthus prey on M. luteus and E. coli. These results might spur application-oriented research on the development of novel antibacterial strategies.
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Affiliation(s)
- Chunling Wang
- College of Life Science, Huizhou University, Huizhou, Guangdong, China
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong, China
| | - Yi Xiao
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong, China
| | - Yong Wang
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong, China
| | - Yumin Liu
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong, China
| | - Qing Yao
- College of Horticulture, South China Agricultural University, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Guangzhou, Guangdong, China
| | - Honghui Zhu
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong, China
- *Correspondence: Honghui Zhu,
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10
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Phillips KE, Akbar S, Stevens DC. Concepts and conjectures concerning predatory performance of myxobacteria. Front Microbiol 2022; 13:1031346. [PMID: 36246230 PMCID: PMC9556981 DOI: 10.3389/fmicb.2022.1031346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 09/14/2022] [Indexed: 01/28/2023] Open
Abstract
Myxobacteria are excellent model organisms for investigation of predator-prey interactions and predatory shaping of microbial communities. This review covers interdisciplinary topics related to myxobacterial predation and provides current concepts and challenges for determining predatory performance. Discussed topics include the role of specialized metabolites during predation, genetic determinants for predatory performance, challenges associated with methodological differences, discrepancies between sequenced and environmental myxobacteria, and factors that influence predation.
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Affiliation(s)
- Kayleigh E. Phillips
- Department of BioMolecular Sciences, The University of Mississippi, Oxford, MS, United States
| | - Shukria Akbar
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin-Madison, Madison, WI, United States,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States
| | - D. Cole Stevens
- Department of BioMolecular Sciences, The University of Mississippi, Oxford, MS, United States,*Correspondence: D. Cole Stevens,
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11
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Pérez J, Contreras-Moreno FJ, Muñoz-Dorado J, Moraleda-Muñoz A. Development versus predation: Transcriptomic changes during the lifecycle of Myxococcus xanthus. Front Microbiol 2022; 13:1004476. [PMID: 36225384 PMCID: PMC9548883 DOI: 10.3389/fmicb.2022.1004476] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/08/2022] [Indexed: 11/13/2022] Open
Abstract
Myxococcus xanthus is a multicellular bacterium with a complex lifecycle. It is a soil-dwelling predator that preys on a wide variety of microorganisms by using a group and collaborative epibiotic strategy. In the absence of nutrients this myxobacterium enters in a unique developmental program by using sophisticated and complex regulatory systems where more than 1,400 genes are transcriptional regulated to guide the community to aggregate into macroscopic fruiting bodies filled of environmentally resistant myxospores. Herein, we analyze the predatosome of M. xanthus, that is, the transcriptomic changes that the predator undergoes when encounters a prey. This study has been carried out using as a prey Sinorhizobium meliloti, a nitrogen fixing bacteria very important for the fertility of soils. The transcriptional changes include upregulation of genes that help the cells to detect, kill, lyse, and consume the prey, but also downregulation of genes not required for the predatory process. Our results have shown that, as expected, many genes encoding hydrolytic enzymes and enzymes involved in biosynthesis of secondary metabolites increase their expression levels. Moreover, it has been found that the predator modifies its lipid composition and overproduces siderophores to take up iron. Comparison with developmental transcriptome reveals that M. xanthus downregulates the expression of a significant number of genes coding for regulatory elements, many of which have been demonstrated to be key elements during development. This study shows for the first time a global view of the M. xanthus lifecycle from a transcriptome perspective.
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12
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Rios-Miguel AB, Smith GJ, Cremers G, van Alen T, Jetten MS, Op den Camp HJ, Welte CU. Microbial paracetamol degradation involves a high diversity of novel amidase enzyme candidates. WATER RESEARCH X 2022; 16:100152. [PMID: 36042984 PMCID: PMC9420511 DOI: 10.1016/j.wroa.2022.100152] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 07/13/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Pharmaceuticals are relatively new to nature and often not completely removed in wastewater treatment plants (WWTPs). Consequently, these micropollutants end up in water bodies all around the world posing a great environmental risk. One exception to this recalcitrant conversion is paracetamol, whose full degradation has been linked to several microorganisms. However, the genes and corresponding proteins involved in microbial paracetamol degradation are still elusive. In order to improve our knowledge of the microbial paracetamol degradation pathway, we inoculated a bioreactor with sludge of a hospital WWTP (Pharmafilter, Delft, NL) and fed it with paracetamol as the sole carbon source. Paracetamol was fully degraded without any lag phase and the enriched microbial community was investigated by metagenomic and metatranscriptomic analyses, which demonstrated that the microbial community was very diverse. Dilution and plating on paracetamol-amended agar plates yielded two Pseudomonas sp. isolates: a fast-growing Pseudomonas sp. that degraded 200 mg/L of paracetamol in approximately 10 h while excreting 4-aminophenol, and a slow-growing Pseudomonas sp. that degraded paracetamol without obvious intermediates in more than 90 days. Each Pseudomonas sp. contained a different highly-expressed amidase (31% identity to each other). These amidase genes were not detected in the bioreactor metagenome suggesting that other as-yet uncharacterized amidases may be responsible for the first biodegradation step of paracetamol. Uncharacterized deaminase genes and genes encoding dioxygenase enzymes involved in the catabolism of aromatic compounds and amino acids were the most likely candidates responsible for the degradation of paracetamol intermediates based on their high expression levels in the bioreactor metagenome and the Pseudomonas spp. genomes. Furthermore, cross-feeding between different community members might have occurred to efficiently degrade paracetamol and its intermediates in the bioreactor. This study increases our knowledge about the ongoing microbial evolution towards biodegradation of pharmaceuticals and points to a large diversity of (amidase) enzymes that are likely involved in paracetamol metabolism in WWTPs.
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Key Words
- 4-AP, 4-aminophenol
- APAP, N-acetyl-p-aminophenol or paracetamol
- Amidase evolution
- Deaminase
- Dioxygenase
- GAC, granular activated carbon
- HGT, horizontal gene transfer
- HQ, hydroquinone
- HRT, hydraulic retention time
- MAG, metagenome-assembled genome
- MBR, membrane bioreactor
- Metagenomics
- Mobile genetic elements
- Pfast, Pseudomonas sp. isolate growing fast on APAP as sole carbon source
- Pseudomonas
- Pslow, Pseudomonas sp. isolate growing slow on APAP as sole carbon source
- SRT, solid retention time
- TPM, transcripts per million
- WWTP, wastewater treatment plant
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Affiliation(s)
- Ana B. Rios-Miguel
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Garrett J. Smith
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Geert Cremers
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Theo van Alen
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Mike S.M. Jetten
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
- Soehngen Institute of Anaerobic Microbiology, Radboud University, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Huub J.M. Op den Camp
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Cornelia U. Welte
- Department of Microbiology, Radboud University, Radboud Institute for Biological and Environmental Sciences, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
- Soehngen Institute of Anaerobic Microbiology, Radboud University, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
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13
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Akbar S, Phillips KE, Misra SK, Sharp JS, Stevens DC. Differential response to prey quorum signals indicates predatory specialization of myxobacteria and ability to predate Pseudomonas aeruginosa. Environ Microbiol 2021; 24:1263-1278. [PMID: 34674390 PMCID: PMC9257966 DOI: 10.1111/1462-2920.15812] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 09/20/2021] [Accepted: 10/07/2021] [Indexed: 11/29/2022]
Abstract
Multiomic analysis of transcriptional and metabolic responses from the predatory myxobacteria Myxococcus xanthus and Cystobacter ferrugineus exposed to prey signalling molecules of the acylhomoserine lactone and quinolone quorum signalling classes provided insight into predatory specialization. Acylhomoserine lactone quorum signals elicited a general response from both myxobacteria. We suggest that this is likely due to the generalist predator lifestyles of myxobacteria and ubiquity of acylhomoserine lactone signals. We also provide data that indicates the core homoserine lactone moiety included in all acylhomoserine lactone scaffolds to be sufficient to induce this general response. Comparing both myxobacteria, unique transcriptional and metabolic responses were observed from Cystobacter ferrugineus exposed to the quinolone signal 2‐heptylquinolin‐4(1H)‐one (HHQ) natively produced by Pseudomonas aeruginosa. We suggest that this unique response and ability to metabolize quinolone signals contribute to the superior predation of P. aeruginosa observed from C. ferrugineus. These results further demonstrate myxobacterial eavesdropping on prey signalling molecules and provide insight into how responses to exogenous signals might correlate with prey range of myxobacteria.
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Affiliation(s)
- Shukria Akbar
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
| | - Kayleigh E Phillips
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
| | - Sandeep K Misra
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
| | - Joshua S Sharp
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA.,Department of Chemistry and Biochemistry, University of Mississippi, University, University, MS, USA
| | - D Cole Stevens
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
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14
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Seef S, Herrou J, de Boissier P, My L, Brasseur G, Robert D, Jain R, Mercier R, Cascales E, Habermann BH, Mignot T. A Tad-like apparatus is required for contact-dependent prey killing in predatory social bacteria. eLife 2021; 10:72409. [PMID: 34505573 PMCID: PMC8460266 DOI: 10.7554/elife.72409] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/09/2021] [Indexed: 12/21/2022] Open
Abstract
Myxococcus xanthus, a soil bacterium, predates collectively using motility to invade prey colonies. Prey lysis is mostly thought to rely on secreted factors, cocktails of antibiotics and enzymes, and direct contact with Myxococcus cells. In this study, we show that on surfaces the coupling of A-motility and contact-dependent killing is the central predatory mechanism driving effective prey colony invasion and consumption. At the molecular level, contact-dependent killing involves a newly discovered type IV filament-like machinery (Kil) that both promotes motility arrest and prey cell plasmolysis. In this process, Kil proteins assemble at the predator-prey contact site, suggesting that they allow tight contact with prey cells for their intoxication. Kil-like systems form a new class of Tad-like machineries in predatory bacteria, suggesting a conserved function in predator-prey interactions. This study further reveals a novel cell-cell interaction function for bacterial pili-like assemblages.
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Affiliation(s)
- Sofiene Seef
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
| | - Julien Herrou
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
| | - Paul de Boissier
- Aix-Marseille Université - CNRS UMR 7288, Institut de Biologie du Développement de Marseille and Turing Center for Living Systems, Marseille, France
| | - Laetitia My
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
| | - Gael Brasseur
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
| | - Donovan Robert
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
| | - Rikesh Jain
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France.,Aix-Marseille Université - CNRS UMR 7288, Institut de Biologie du Développement de Marseille and Turing Center for Living Systems, Marseille, France
| | - Romain Mercier
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
| | - Eric Cascales
- Aix-Marseille Université - CNRS UMR 7255, Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Bianca H Habermann
- Aix-Marseille Université - CNRS UMR 7288, Institut de Biologie du Développement de Marseille and Turing Center for Living Systems, Marseille, France
| | - Tâm Mignot
- Aix-Marseille Université - CNRS UMR 7283, Institut de Microbiologie de la Méditerranée and Turing Center for Living Systems, Marseille, France
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15
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Wen T, Koonin EV, Cheong KH. An alternating active-dormitive strategy enables disadvantaged prey to outcompete the perennially active prey through Parrondo's paradox. BMC Biol 2021; 19:168. [PMID: 34425802 PMCID: PMC8383410 DOI: 10.1186/s12915-021-01097-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 07/14/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Dormancy is widespread in nature, but while it can be an effective adaptive strategy in fluctuating environments, the dormant forms are costly due to the inability to breed and the relatively high energy consumption. We explore mathematical models of predator-prey systems, in order to assess whether dormancy can be an effective adaptive strategy to outcompete perennially active (PA) prey, even when both forms of the dormitive prey (active and dormant) are individually disadvantaged. RESULTS We develop a dynamic population model by introducing an additional dormitive prey population to the existing predator-prey model which can be active (active form) and enter dormancy (dormant form). In this model, both forms of the dormitive prey are individually at a disadvantage compared to the PA prey and thus would go extinct due to their low growth rate, energy waste on the production of dormant prey, and the inability of the latter to grow autonomously. However, the dormitive prey can paradoxically outcompete the PA prey with superior traits and even cause its extinction by alternating between the two losing strategies. We observed higher fitness of the dormitive prey in rich environments because a large predator population in a rich environment cannot be supported by the prey without adopting an evasive strategy, that is, dormancy. In such environments, populations experience large-scale fluctuations, which can be survived by dormitive but not by PA prey. CONCLUSION We show that dormancy can be an effective adaptive strategy to outcompete superior prey, recapitulating the game-theoretic Parrondo's paradox, where two losing strategies combine to achieve a winning outcome. We suggest that the species with the ability to switch between the active and dormant forms can dominate communities via competitive exclusion.
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Affiliation(s)
- Tao Wen
- Science, Mathematics and Technology Cluster, Singapore University of Technology and Design (SUTD), 8 Somapah Road, S487372, Singapore, Singapore
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA
| | - Kang Hao Cheong
- Science, Mathematics and Technology Cluster, Singapore University of Technology and Design (SUTD), 8 Somapah Road, S487372, Singapore, Singapore.
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16
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Akbar S, Stevens DC. Functional genomics study of Pseudomonas putida to determine traits associated with avoidance of a myxobacterial predator. Sci Rep 2021; 11:16445. [PMID: 34385565 PMCID: PMC8360965 DOI: 10.1038/s41598-021-96046-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 07/28/2021] [Indexed: 12/13/2022] Open
Abstract
Predation contributes to the structure and diversity of microbial communities. Predatory myxobacteria are ubiquitous to a variety of microbial habitats and capably consume a broad diversity of microbial prey. Predator-prey experiments utilizing myxobacteria have provided details into predatory mechanisms and features that facilitate consumption of prey. However, prey resistance to myxobacterial predation remains underexplored, and prey resistances have been observed exclusively from predator-prey experiments that included the model myxobacterium Myxococcus xanthus. Utilizing a predator-prey pairing that instead included the myxobacterium, Cystobacter ferrugineus, with Pseudomonas putida as prey, we observed surviving phenotypes capable of eluding predation. Comparative transcriptomics between P. putida unexposed to C. ferrugineus and the survivor phenotype suggested that increased expression of efflux pumps, genes associated with mucoid conversion, and various membrane features contribute to predator avoidance. Unique features observed from the survivor phenotype when compared to the parent P. putida include small colony variation, efflux-mediated antibiotic resistance, phenazine-1-carboxylic acid production, and increased mucoid conversion. These results demonstrate the utility of myxobacterial predator-prey models and provide insight into prey resistances in response to predatory stress that might contribute to the phenotypic diversity and structure of bacterial communities.
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Affiliation(s)
- Shukria Akbar
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
| | - D Cole Stevens
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA.
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17
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Myxococcus xanthus predation of Gram-positive or Gram-negative bacteria is mediated by different bacteriolytic mechanisms. Appl Environ Microbiol 2021; 87:AEM.02382-20. [PMID: 33310723 PMCID: PMC8090889 DOI: 10.1128/aem.02382-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Myxococcus xanthus kills other species to use their biomass as energy source. Its predation mechanisms allow feeding on a broad spectrum of bacteria, but the identity of predation effectors and their mode of action remains largely unknown. We initially focused on the role of hydrolytic enzymes for prey killing and compared the activity of secreted M. xanthus proteins against four prey strains. 72 secreted proteins were identified by mass spectrometry, and among them a family 19 glycoside hydrolase that displayed bacteriolytic activity in vivo and in vitro This enzyme, which we name LlpM (lectin/lysozyme-like protein of M. xanthus), was not essential for predation, indicating that additional secreted components are required to disintegrate prey. Furthermore, secreted proteins lysed only Gram-positive, but not Gram-negative species. We thus compared the killing of different preys by cell-associated mechanisms: Individual M. xanthus cells killed all four test strains in a cell-contact dependent manner, but were only able to disintegrate Gram-negative, not Gram-positive cell envelopes. Thus, our data indicate that M. xanthus uses different, multifactorial mechanisms for killing and degrading different preys. Besides secreted enzymes, cell-associated mechanisms that have not been characterized so far, appear to play a major role for prey killing.IMPORTANCEPredation is an important survival strategy of the widespread myxobacteria, but it remains poorly understood on the mechanistic level. Without a basic understanding of how prey cell killing and consumption is achieved, it also remains difficult to investigate the role of predation for the complex myxobacterial lifestyle, reciprocal predator-prey relationships or the impact of predation on complex bacterial soil communities.We study predation in the established model organism Myxococcus xanthus, aiming to dissect the molecular mechanisms of prey cell lysis. In this study, we addressed the role of secreted bacteriolytic proteins, as well as potential mechanistic differences in the predation of Gram-positive and Gram-negative bacteria. Our observation shows that secreted enzymes are sufficient for killing and degrading Gram-positive species, but that cell-associated mechanisms may play a major role for killing Gram-negative and Gram-positive prey on fast timescales.
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18
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Pishchany G, Kolter R. On the possible ecological roles of antimicrobials. Mol Microbiol 2020; 113:580-587. [PMID: 31975454 DOI: 10.1111/mmi.14471] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/13/2020] [Accepted: 01/17/2020] [Indexed: 12/29/2022]
Abstract
The Introduction of antibiotics into the clinical use in the middle of the 20th century had a profound impact on modern medicine and human wellbeing. The contribution of these wonder molecules to public health and science is hard to overestimate. Much research has informed our understanding of antibiotic mechanisms of action and resistance at inhibitory concentrations in the lab and in the clinic. Antibiotics, however, are not a human invention as most of them are either natural products produced by soil microorganisms or semisynthetic derivatives of natural products. Because we use antibiotics to inhibit the bacterial growth, it is generally assumed that growth inhibition is also their primary ecological function in the environment. Nevertheless, multiple studies point to diverse nonlethal effects that are exhibited at lower levels of antibiotics. Here we review accumulating evidence of antibiosis and of alternative functions of antibiotics exhibited at subinhibitory concentrations. We also speculate on how these effects might alter phenotypes, fitness, and community composition of microbes in the context of the environment and suggest directions for future research.
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Affiliation(s)
- Gleb Pishchany
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Roberto Kolter
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
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19
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Thiery S, Kaimer C. The Predation Strategy of Myxococcus xanthus. Front Microbiol 2020; 11:2. [PMID: 32010119 PMCID: PMC6971385 DOI: 10.3389/fmicb.2020.00002] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 01/03/2020] [Indexed: 11/20/2022] Open
Abstract
Myxobacteria are ubiquitous in soil environments. They display a complex life cycle: vegetatively growing cells coordinate their motility to form multicellular swarms, which upon starvation aggregate into large fruiting bodies where cells differentiate into spores. In addition to growing as saprophytes, Myxobacteria are predators that actively kill bacteria of other species to consume their biomass. In this review, we summarize research on the predation behavior of the model myxobacterium Myxococcus xanthus, which can access nutrients from a broad spectrum of microorganisms. M. xanthus displays an epibiotic predation strategy, i.e., it induces prey lysis from the outside and feeds on the released biomass. This predatory behavior encompasses various processes: Gliding motility and induced cell reversals allow M. xanthus to encounter prey and to remain within the area to sweep up its biomass, which causes the characteristic “rippling” of preying populations. Antibiotics and secreted bacteriolytic enzymes appear to be important predation factors, which are possibly targeted to prey cells with the aid of outer membrane vesicles. However, certain bacteria protect themselves from M. xanthus predation by forming mechanical barriers, such as biofilms and mucoid colonies, or by secreting antibiotics. Further understanding the molecular mechanisms that mediate myxobacterial predation will offer fascinating insight into the reciprocal relationships of bacteria in complex communities, and might spur application-oriented research on the development of novel antibacterial strategies.
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Affiliation(s)
- Susanne Thiery
- Department of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Christine Kaimer
- Department of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
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20
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Wang C, Liu X, Zhang P, Wang Y, Li Z, Li X, Wang R, Shang Z, Yan J, He H, Wang J, Hu W, Li Y. Bacillus licheniformisescapes fromMyxococcus xanthuspredation by deactivating myxovirescin A through enzymatic glucosylation. Environ Microbiol 2019; 21:4755-4772. [DOI: 10.1111/1462-2920.14817] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/17/2019] [Accepted: 10/01/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Chuandong Wang
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
- School of Life ScienceShandong University Qingdao Shandong 266237 China
| | - Xinlin Liu
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
| | - Peng Zhang
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
| | - Yan Wang
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
| | - Zhifeng Li
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
| | - Xun Li
- Department of Medicinal Chemistry, Key Laboratory of Chemistry and Chemical Biology (Ministry of Education), School of Pharmaceutical ScienceShandong University Jinan Shandong 250012 China
| | - Renqing Wang
- School of Life ScienceShandong University Qingdao Shandong 266237 China
| | - Zhaohui Shang
- Gudong Petroleum Production Factory, Shengli Oil‐Field of Sinopec Dongying Shandong 257237 China
| | - Jingen Yan
- Gudong Petroleum Production Factory, Shengli Oil‐Field of Sinopec Dongying Shandong 257237 China
| | - Haifeng He
- Gudong Petroleum Production Factory, Shengli Oil‐Field of Sinopec Dongying Shandong 257237 China
| | - Jing Wang
- College of Pharmaceutical ScienceShandong University of Traditional Chinese Medicine Jinan Shandong 250355 China
| | - Wei Hu
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
| | - Yuezhong Li
- State Key Laboratory of Microbial Technology, Microbial Technology InstituteShandong University Qingdao Shandong 266237 China
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21
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Muñoz-Dorado J, Moraleda-Muñoz A, Marcos-Torres FJ, Contreras-Moreno FJ, Martin-Cuadrado AB, Schrader JM, Higgs PI, Pérez J. Transcriptome dynamics of the Myxococcus xanthus multicellular developmental program. eLife 2019; 8:e50374. [PMID: 31609203 PMCID: PMC6791715 DOI: 10.7554/elife.50374] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 10/04/2019] [Indexed: 01/09/2023] Open
Abstract
The bacterium Myxococcus xanthus exhibits a complex multicellular life cycle. In the presence of nutrients, cells prey cooperatively. Upon starvation, they enter a developmental cycle wherein cells aggregate to produce macroscopic fruiting bodies filled with resistant myxospores. We used RNA-Seq technology to examine the transcriptome of the 96 hr developmental program. These data revealed that 1415 genes were sequentially expressed in 10 discrete modules, with expression peaking during aggregation, in the transition from aggregation to sporulation, or during sporulation. Analysis of genes expressed at each specific time point provided insights as to how starving cells obtain energy and precursors necessary for assembly of fruiting bodies and into developmental production of secondary metabolites. This study offers the first global view of developmental transcriptional profiles and provides important tools and resources for future studies.
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Affiliation(s)
- José Muñoz-Dorado
- Departamento de Microbiología, Facultad de CienciasUniversidad de GranadaGranadaSpain
| | | | | | | | | | - Jared M Schrader
- Department of Biological SciencesWayne State UniversityDetroitUnited States
| | - Penelope I Higgs
- Department of Biological SciencesWayne State UniversityDetroitUnited States
| | - Juana Pérez
- Departamento de Microbiología, Facultad de CienciasUniversidad de GranadaGranadaSpain
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22
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Whitworth DE. Interspecies conflict affects RNA expression. FEMS Microbiol Lett 2019; 365:4966981. [PMID: 29648585 DOI: 10.1093/femsle/fny096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 04/09/2018] [Indexed: 12/13/2022] Open
Abstract
Predation is an extreme form of competition between bacteria, involving the secretion of antimicrobial substances by predators, often packaged within outer membrane vesicles (OMVs). Recent studies into the Myxococcus xanthus/Escherichia coli predator/prey relationship have illuminated transcriptional changes during predation, identifying likely targets of predatory attack in the prey and nutrient assimilation strategies of the predator. Abundant non-coding RNAs can be observed in the predator and prey transcriptomes, with evidence of predation-dependent regulation of RNA levels. Given the observed secretion of regulatory RNAs within OMVs by bacteria, it will next be exciting to test whether the intercellular trafficking of regulatory RNAs is employed by predator and/or prey in their survival struggles.
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Affiliation(s)
- David E Whitworth
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Ceredigion, SY23 3DD, UK
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23
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Complete genome sequence of Bradymonas sediminis FA350T, the first representative of the order Bradymonadales. Mar Genomics 2019. [DOI: 10.1016/j.margen.2019.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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24
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Bretl DJ, Ladd KM, Atkinson SN, Müller S, Kirby JR. Suppressor mutations reveal an NtrC-like response regulator, NmpR, for modulation of Type-IV Pili-dependent motility in Myxococcus xanthus. PLoS Genet 2018; 14:e1007714. [PMID: 30346960 PMCID: PMC6211767 DOI: 10.1371/journal.pgen.1007714] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 11/01/2018] [Accepted: 09/26/2018] [Indexed: 12/03/2022] Open
Abstract
Two-component signaling systems (TCS) regulate bacterial responses to environmental signals through the process of protein phosphorylation. Specifically, sensor histidine kinases (SK) recognize signals and propagate the response via phosphorylation of a cognate response regulator (RR) that functions to initiate transcription of specific genes. Signaling within a single TCS is remarkably specific and cross-talk between TCS is limited. However, regulation of the flow of information through complex signaling networks that include closely related TCS remains largely unknown. Additionally, many bacteria utilize multi-component signaling networks which provide additional genetic and biochemical interactions that must be regulated for signaling fidelity, input and output specificity, and phosphorylation kinetics. Here we describe the characterization of an NtrC-like RR that participates in regulation of Type-IV pilus-dependent motility of Myxococcus xanthus and is thus named NmpR, NtrC Modulator of Pili Regulator. A complex multi-component signaling system including NmpR was revealed by suppressor mutations that restored motility to cells lacking PilR, an evolutionarily conserved RR required for expression of pilA encoding the major Type-IV pilus monomer found in many bacterial species. The system contains at least four signaling proteins: a SK with a protoglobin sensor domain (NmpU), a hybrid SK (NmpS), a phospho-sink protein (NmpT), and an NtrC-like RR (NmpR). We demonstrate that ΔpilR bypass suppressor mutations affect regulation of the NmpRSTU multi-component system, such that NmpR activation is capable of restoring expression of pilA in the absence of PilR. Our findings indicate that pilus gene expression in M. xanthus is regulated by an extended network of TCS which interact to refine control of pilus function.
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Affiliation(s)
- Daniel J. Bretl
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - Kayla M. Ladd
- Department of Biochemistry, University of Iowa, Iowa City, Iowa, United States of America
| | - Samantha N. Atkinson
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States of America
- Department of Bioinformatics, University of Iowa, Iowa City, Iowa, United States of America
| | - Susanne Müller
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - John R. Kirby
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States of America
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