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Pozo F, Borbor M, Solórzano R, Sonnenholzner S, Bayot B. Optimized swarming motility assay to identify anti-virulence products against Vibrio parahaemolyticus, a pathogen of farmed shrimp. MethodsX 2024; 12:102622. [PMID: 38425495 PMCID: PMC10904179 DOI: 10.1016/j.mex.2024.102622] [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: 10/13/2023] [Accepted: 02/19/2024] [Indexed: 03/02/2024] Open
Abstract
Swarming motility is a type of movement used by pathogenic flagellated bacteria as virulence factor to colonize surfaces and cause damage to the host. Vibrio parahaemolyticus is a pathogenic flagellated bacterium that increases its virulence by switching from swimmer to swarming cells. The hosts of pathogenic V. parahaemolyticus include farmed shrimp. Therefore, methods to detect and quantify this movement are important to control shrimp diseases caused by pathogenic V. parahaemolyticus strains. We developed an optimized swarming motility assay by identifying the most optimal type of agar, and drying time of the culture medium, agar concentration and volume of the bacterial culture to achieve the fastest swarming motility during the migration of V. parahaemolyticus on Petri dishes during a 24-hour incubation period. The method includes data analysis that could be used as a tool to identify potential anti-virulence products by comparing the slopes of the linearized diameters of the swarming halos of bacteria treated with the products, as they migrate on Petri dishes over a 24-hour incubation period. Here we report:•A simple method for detection and quantification of swarming motility halos of V. parahaemolyticus bacteria.•A method that could be used as a tool to identify potential anti-virulence products.
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Affiliation(s)
- Francisco Pozo
- Escuela Superior Politécnica del Litoral, ESPOL, Facultad de Ciencias de la Vida, FCV, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
- Pontificia Universidad Católica del Ecuador, Sede Manabí, Portoviejo, Ecuador
| | - Martha Borbor
- Escuela Superior Politécnica del Litoral, ESPOL, Centro Nacional de Acuicultura e Investigaciones Marinas, CENAIM, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
| | - Ramiro Solórzano
- Escuela Superior Politécnica del Litoral, ESPOL, Centro Nacional de Acuicultura e Investigaciones Marinas, CENAIM, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
| | - Stanislaus Sonnenholzner
- Escuela Superior Politécnica del Litoral, ESPOL, Centro Nacional de Acuicultura e Investigaciones Marinas, CENAIM, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
- Escuela Superior Politécnica del Litoral, ESPOL, Facultad de Ingeniería Marítima y Ciencias del Mar, FIMCM, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
| | - Bonny Bayot
- Escuela Superior Politécnica del Litoral, ESPOL, Centro Nacional de Acuicultura e Investigaciones Marinas, CENAIM, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
- Escuela Superior Politécnica del Litoral, ESPOL, Facultad de Ingeniería Marítima y Ciencias del Mar, FIMCM, Campus Gustavo Galindo Km 30.5 Vía Perimetral, Guayaquil P.O. Box 09-01-5863, Ecuador
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Benítez SV, Carrasco R, Giraldo JD, Schoebitz M. Microbeads as carriers for Bacillus pumilus: a biofertilizer focus on auxin production. J Microencapsul 2024; 41:170-189. [PMID: 38469757 DOI: 10.1080/02652048.2024.2324812] [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: 10/03/2023] [Accepted: 02/19/2024] [Indexed: 03/13/2024]
Abstract
The study aimed to develop a solid biofertilizer using Bacillus pumilus, focusing on auxin production to enhance plant drought tolerance. Methods involved immobilising B. pumilus in alginate-starch beads, focusing on microbial concentration, biopolymer types, and environmental conditions. The optimal formulation showed a diameter of 3.58 mm ± 0.18, a uniform size distribution after 15 h of drying at 30 °C, a stable bacterial concentration (1.99 × 109 CFU g-1 ± 1.03 × 109 over 180 days at room temperature), a high auxin production (748.8 µg g-1 ± 10.3 of IAA in 7 days), and a water retention capacity of 37% ± 4.07. In conclusion, this new formulation of alginate + starch + L-tryptophan + B. pumilus has the potential for use in crops due to its compelling water retention, high viability in storage at room temperature, and high auxin production, which provides commercial advantages.
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Affiliation(s)
- Solange V Benítez
- Departamento de Suelos y Recursos Naturales, Facultad de Agronomía, Universidad de Concepción, Concepción, Chile
| | - Rocio Carrasco
- Departamento de Suelos y Recursos Naturales, Facultad de Agronomía, Universidad de Concepción, Concepción, Chile
| | - Juan D Giraldo
- Escuela de Ingeniería Ambiental, Instituto de Acuicultura, Universidad Austral de Chile, Sede Puerto Montt, Puerto Montt, Chile
| | - Mauricio Schoebitz
- Departamento de Suelos y Recursos Naturales, Facultad de Agronomía, Universidad de Concepción, Concepción, Chile
- Laboratory of Biofilms and Environmental Microbiology, Center of Biotechnology, University of Concepción, Concepción, Chile
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Goo E, Hwang I. Control of bacterial quorum threshold for metabolic homeostasis and cooperativity. Microbiol Spectr 2024; 12:e0335323. [PMID: 38084969 PMCID: PMC10783058 DOI: 10.1128/spectrum.03353-23] [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: 09/13/2023] [Accepted: 11/02/2023] [Indexed: 01/13/2024] Open
Abstract
IMPORTANCE The mechanisms used by various bacteria to determine whether their density is sufficient to meet the QS threshold, how stringently bacterial cells block QS initiation until the QS threshold is reached, and the impacts of low-density bacterial cells encountering conditions that exceed the QS threshold are longstanding gaps in QS research. We demonstrated that translational control of the QS signaling biosynthetic gene creates a stringent QS threshold to maintain metabolic balance at low cell densities. The emergence of non-cooperative cells underlines the critical role of stringent QS modulation in maintaining the integrity of the bacterial QS system, demonstrating that a lack of such control can serve as a selection pressure. The fate of quorum-calling cells exposed to exceeding the QS threshold clarifies QS bacteria evolution in complex ecosystems.
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Affiliation(s)
- Eunhye Goo
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Ingyu Hwang
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
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Priya PS, Boopathi S, Murugan R, Haridevamuthu B, Arshad A, Arockiaraj J. Quorum sensing signals: Aquaculture risk factor. REVIEWS IN AQUACULTURE 2023; 15:1294-1310. [DOI: 10.1111/raq.12774] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/28/2022] [Indexed: 10/16/2023]
Abstract
AbstractBacteria produce several virulence factors and cause massive mortality in fish and crustaceans. Abundant quorum sensing (QS) signals and high cell density are essentially required for the production of such virulence factors. Although several strategies have been developed to control aquatic pathogens through antibiotics and QS inhibition, the impact of pre‐existing QS signals in the aquatic environment has been overlooked. QS signals cause detrimental effects on mammalian cells and induce cell death by interfering with multiple cellular pathways. Moreover, QS signals not only function as a messenger, but also annihilate the functions of the host immune system which implies that QS signals should be designated as a major virulence factor. Despite QS signals' role has been well documented in mammalian cells, their impact on aquatic organisms is still at the budding stage. However, many aquatic organisms produce enzymes that degrade and detoxify such QS signals. In addition, physical and chemical factors also determine the stability of the QS signals in the aqueous environment. The balance between QS signals and existing QS signals degrading factors essentially determines the disease progression in aquatic organisms. In this review, we highlight the impact of QS signals on aquatic organisms and further discussed potential alternative strategies to control disease progression.
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Affiliation(s)
- P. Snega Priya
- Department of Biotechnology, College of Science and Humanities SRM Institute of Science and Technology Chennai India
| | - Seenivasan Boopathi
- Department of Biotechnology, College of Science and Humanities SRM Institute of Science and Technology Chennai India
| | - Raghul Murugan
- Department of Biotechnology, College of Science and Humanities SRM Institute of Science and Technology Chennai India
| | - B. Haridevamuthu
- Department of Biotechnology, College of Science and Humanities SRM Institute of Science and Technology Chennai India
| | - Aziz Arshad
- International Institute of Aquaculture and Aquatic Sciences (I‐AQUAS) Universiti Putra Malaysia Negeri Sembilan Malaysia
| | - Jesu Arockiaraj
- Department of Biotechnology, College of Science and Humanities SRM Institute of Science and Technology Chennai India
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Zhao J, Li Y, Huang Y, Jin L, Xu Y, Xu M, Quan C, Chen M. Heterologous expression of quorum sensing transcriptional regulator LitR and its function in virulence-related gene regulation in foodborne pathogen Aeromonas hydrophila. Mol Biol Rep 2023; 50:2049-2060. [PMID: 36542235 DOI: 10.1007/s11033-022-07866-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/11/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Aeromonas hydrophila is an important foodborne and zoonotic pathogen causing serious diseases. Hence, revealing the pathogenic mechanism of A. hydrophila will be of importance in the development of novel therapies. Aeromonas hydrophila litR was reported to be regulated by two quorum sensing (QS) pathways, indicating that it is involved in QS network regulation correlated with bacterial virulence. However, the function of LitR is currently not understood. Therefore, we aimed to reveal the potential regulatory mechanisms of LitR on virulence-related genes. METHODS AND RESULTS In this study, amino acid sequences analysis of LitR was conducted, providing bioinformatics evidence for its function as a potential transcriptional regulator. LitR protein was heterologous expressed, purified and its in-vitro multimeric forms were observed with gel filtration chromatography. The correlation between intracellular LitR expression level and cell density was analyzed with immunoblots. Regulation mechanisms of LitR on several important virulence-related factors were investigated with qRT-PCR, EMSA, DNase I footprinting and microscale thermophoresis binding assays, etc. Results showed that recombinant LitR protein aggregated mainly as dimer and hexamer in vitro. Intracellular expression level of LitR was positively correlated with cell density of A. hydrophila. Furthermore, LitR exhibited complicated regulation modes on virulence-related genes; it could directly bind to promoter regions of the hemolysin, serine protease and T6SS effector protein VgrG encoded genes. The promoter region of the hemolysin gene showed high binding affinity and mainly two binding sites for LitR. Different dissociation constants were obtained for LitR interaction with the hemolysin gene binding motifs I and II. Assays focusing on physiological characteristics of A. hydrophila prove that LitR positively regulated hemolytic and total extracellular protease activities. CONCLUSIONS This study investigated the function of LitR as a quorum sensing transcriptional regulator in regulation of virulence-related genes, which will help reveal the mechanisms of A. hydrophila pathogenicity. LitR could serve as a potential target for development of new antimicrobial agents from the perspective of QS regulation.
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Affiliation(s)
- Jing Zhao
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian, 116600, China
- College of Life Science, Dalian Minzu University, Dalian, 116600, China
| | - Yue Li
- College of Bioengineering, Dalian Polytechnic University, Dalian, 116034, China
| | - Yan Huang
- College of Bioengineering, Dalian Polytechnic University, Dalian, 116034, China
| | - Liming Jin
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian, 116600, China
- College of Life Science, Dalian Minzu University, Dalian, 116600, China
| | - Yongbin Xu
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian, 116600, China
- College of Life Science, Dalian Minzu University, Dalian, 116600, China
| | - Menghao Xu
- College of Life Science, Dalian Minzu University, Dalian, 116600, China
| | - Chunshan Quan
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian, 116600, China.
- College of Life Science, Dalian Minzu University, Dalian, 116600, China.
| | - Ming Chen
- College of Bioengineering, Dalian Polytechnic University, Dalian, 116034, China.
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Liao J, Li Z, Xiong D, Shen D, Wang L, Shao X, Li T, Qian G. A Novel and Efficient Platform for Discovering Noncanonical Quorum-Quenching Proteins. Microbiol Spectr 2023; 11:e0343722. [PMID: 36475880 PMCID: PMC9927378 DOI: 10.1128/spectrum.03437-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 11/11/2022] [Indexed: 12/12/2022] Open
Abstract
Quorum sensing (QS) is a well-known chemical signaling system responsible for intercellular communication that is widespread in bacteria. Acyl-homoserine lactone (AHL) is the most-studied QS signal. Previously, bacterially encoded AHL-degrading enzymes were considered to be canonical quorum-quenching proteins that have been widely used to control pathogenic infections. Here, we report a novel platform that enabled the efficient discovery of noncanonical AHL quorum-quenching proteins. This platform initially asked bacteriologists to carry out comparative genomic analyses between phylogenetically related AHL-producing and non-AHL-producing members to identify genes that are conservatively shared by non-AHL-producing members but absent in AHL-producing species. These candidate genes were then introduced into recombinant AHL-producing E. coli to screen for target proteins with the ability to block AHL production. Via this platform, we found that non-AHL-producing Lysobacter containing numerous environmentally ubiquitous members encoded a conserved glycosyltransferase-like protein Le4759, which was experimentally shown to be a noncanonical AHL-quenching protein. Le4759 could not directly degrade exogenous AHL but rather recognized and altered the activities of multiple AHL synthases through protein-protein interactions. This versatile capability enabled Le4759 to block specific AHL synthase such as CarI from Pectobacterium carotovorum to reduce its protein abundance to suppress AHL synthesis, thereby impairing bacterial infection. Thus, this study provided bacteriologists with a unique platform to discover noncanonical quorum-quenching proteins that could be developed as promising next-generation drug candidates to overcome emerging bacterial antibiotic resistance. IMPORTANCE Targeting and blocking bacterial quorum sensing (QS), the process known as quorum quenching (QQ) is an effective mean to control bacterial infection and overcome the emerging antibiotic resistance. Previously, diverse QS signal-degradation enzymes are identified as canonical QQ proteins. Here, we provided a novel and universal platform that enabled to discover previously unidentified noncanonical QQ proteins that were unable to degrade acyl-homoserine lactone (AHL) but could block AHL generation by recognizing multiple AHL synthases via direct protein-protein interactions. Our findings are believed to trigger broad interest for bacteriologists to identify potentially widely distributed noncanonical QQ proteins that have great potential for developing next-generation anti-infectious drugs.
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Affiliation(s)
- Jinxing Liao
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Zihan Li
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Dan Xiong
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Danyu Shen
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Lu Wang
- Medical College, China Three Gorges University, Yichang, People’s Republic of China
| | - Xiaolong Shao
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Tao Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, People’s Republic of China
| | - Guoliang Qian
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
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Echlin M, Aguilar B, Shmulevich I. Characterizing the Impact of Communication on Cellular and Collective Behavior Using a Three-Dimensional Multiscale Cellular Model. ENTROPY (BASEL, SWITZERLAND) 2023; 25:319. [PMID: 36832685 PMCID: PMC9955575 DOI: 10.3390/e25020319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/29/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
Communication between cells enables the coordination that drives structural and functional complexity in biological systems. Both single and multicellular organisms have evolved diverse communication systems for a range of purposes, including synchronization of behavior, division of labor, and spatial organization. Synthetic systems are also increasingly being engineered to utilize cell-cell communication. While research has elucidated the form and function of cell-cell communication in many biological systems, our knowledge is still limited by the confounding effects of other biological phenomena at play and the bias of the evolutionary background. In this work, our goal is to push forward the context-free understanding of what impact cell-cell communication can have on cellular and population behavior to more fully understand the extent to which cell-cell communication systems can be utilized, modified, and engineered. We use an in silico model of 3D multiscale cellular populations, with dynamic intracellular networks interacting via diffusible signals. We focus on two key communication parameters: the effective interaction distance at which cells are able to interact and the receptor activation threshold. We found that cell-cell communication can be divided into six different forms along the parameter axes, three asocial and three social. We also show that cellular behavior, tissue composition, and tissue diversity are all highly sensitive to both the general form and specific parameters of communication even when the cellular network has not been biased towards that behavior.
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Affiliation(s)
- Moriah Echlin
- Prostate Cancer Research Center, Faculty of Medicine and Health Technology, Tampere University, FI-33014 Tampere, Finland
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Boris Aguilar
- Institute for Systems Biology, Seattle, WA 98109, USA
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Xu Y, Zhang T, Che J, Yi J, Wei L, Li H. Evaluation of the antimicrobial mechanism of biogenic selenium nanoparticles against Pseudomonas fluorescens. BIOFOULING 2023; 39:157-170. [PMID: 37038871 DOI: 10.1080/08927014.2023.2199932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Selenium nanoparticles (SeNPs) can be biosynthesized by most Lactic acid bacteria thereby converting toxic sodium into SeNPs. However, few studies have reported the antimicrobial activity of biogenic SeNPs against Pseudomonas fluorescens which are the main species of psychrotrophic bacteria in raw milk. This study reported the synthesis and characterization of SeNPs from Lactobacillus casei ZK-AS 1.1482, and the antimicrobial mechanism against P. fluorescens ATCC 13525. The synthesized SeNPs were amorphous with sizes ranging from 52 to 103 nm. Fourier transform infrared spectroscopy (FT-IR) spectra showed the presence of proteins, polysaccharides, and lipids on the surface of particles, which evidently stabilized the SeNPs structure and morphology. Energy-dispersive X-ray (EDX) analysis revealed that the nanoparticles contained selenium. In addition, the minimal inhibitory concentration (MIC) of SeNPs against P. fluorescens ATCC 13525 was 0.1 mg ml-1 and the biofilm inhibition rate was 43.52 ± 0.26%. SeNPs decreased the number of living bacteria observed by confocal laser scanning microscopy (CLSM). Meanwhile, after SeNPs treatment, the intracellular adenosine triphosphate (ATP) concentration and antioxidant enzyme activity decreased, the content of reactive oxygen species (ROS) and the malondialdehyde (MDA) content increased, and lipid peroxidation intensified. Real-time fluorescence quantitative PCR (RT-qPCR) assay showed that the expression of flgA, luxR, lapD, MCP, cheA, c-di-GMP, phoB, and pstC gene were down-regulated after SeNPs treatment. The rfbC and DegT/DnrJ/EryC1/StrS gene were significantly up-regulated, indicating that SeNPs could destroy the integrity of cell membrane and thus play an antimicrobial role. Biogenic SeNPs are expected to be developed as an efficient and novel antimicrobial agent for application in the food industry.
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Affiliation(s)
- Ying Xu
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Ting Zhang
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Jiarui Che
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Jiajia Yi
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Lina Wei
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Hongliang Li
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
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Antibiofilm, AntiAdhesive and Anti-Invasive Activities of Bacterial Lysates Extracted from Pediococcus acidilactici against Listeria monocytogenes. Foods 2022; 11:foods11192948. [PMID: 36230024 PMCID: PMC9562709 DOI: 10.3390/foods11192948] [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: 08/19/2022] [Revised: 09/13/2022] [Accepted: 09/16/2022] [Indexed: 11/17/2022] Open
Abstract
This study aimed to investigate whether bacterial lysates (BLs) extracted from Pediococcus acidilactici reduce Listeria monocytogenes biofilm formation, as well as adhesion to and invasion of human intestinal epithelial cells. Pretreatment with P. acidilactici BLs (20, 40, and 80 μg/mL) significantly inhibited L. monocytogenes biofilm formation on the surface of polystyrene (p < 0.05). Fluorescence and scanning-electron-microscopic analyses indicated that L. monocytogenes biofilm comprised a much less dense layer of more-dispersed cells in the presence of P. acidilactici BLs. Moreover, biofilm-associated genes, such as flaA, fliG, flgE, motB, degU, agrA, and prfA, were significantly downregulated in the presence of P. acidilactici BLs (p < 0.05), suggesting that P. acidilactici BLs prevent L. monocytogenes biofilm development by suppressing biofilm-associated genes. Although P. acidilactici BLs did not dose-dependently inhibit L. monocytogenes adhesion to and invasion of intestinal epithelial cells, the BLs effectively inhibited adhesion and invasion at 40 and 80 μg/mL (p < 0.05). Supporting these findings, P. acidilactici BLs significantly downregulated L. monocytogenes transcription of genes related to adhesion and invasion, specifically fbpA, ctaP, actA, lapB, ami, and inlA. Collectively, these results suggest that P. acidilactici BLs have the potential to reduce health risks from L. monocytogenes.
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Effect of Cyclodextrins on the Biofilm Formation Capacity of Pseudomonas aeruginosa PAO1. Molecules 2022; 27:molecules27113603. [PMID: 35684540 PMCID: PMC9181962 DOI: 10.3390/molecules27113603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/30/2022] [Accepted: 05/30/2022] [Indexed: 02/01/2023] Open
Abstract
Quorum sensing (QS) is a population-density-dependent communication process of microorganisms to coordinate their activities by producing and detecting low-molecular-weight signal molecules. In pathogenic bacteria, the property controlled by QS is often related to infectivity, e.g., biofilm formation. Molecular encapsulation of the QS signals is an innovative method to prevent the signals binding to the receptors and to attenuate QS. Cyclodextrins (CDs) may form an inclusion complex with the signals, thus reducing the communication (quorum quenching, QQ). A systematic study was performed with α-, β-cyclodextrin, and their random methylated, quaternary amino and polymer derivatives to evaluate and compare their effects on the biofilm formation of Pseudomonas aeruginosa. To examine the concentration-, temperature- and time-dependency of the QQ effect, the CDs were applied at a 0.1–12.5 mM concentration range, and biofilm formation was studied after 6, 24, 48 and 72 h at 22 and 30 °C. According to the results, the QS mechanism was significantly inhibited; the size of the cavity, the structure of the substituents, as well as the monomeric or polymeric character together with the concentration of the CDs have been identified as key influencing factors of biofilm formation. Statistically determined effective concentration values demonstrated outstanding efficiency (higher than 80% inhibition) of α-CD and its random methylated and polymer derivatives both on the short and long term. In summary, the potential value of CDs as inhibitors of QS should be considered since the inhibition of biofilm formation could significantly impact human health and the environment.
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Frequency modulation of a bacterial quorum sensing response. Nat Commun 2022; 13:2772. [PMID: 35589697 PMCID: PMC9120067 DOI: 10.1038/s41467-022-30307-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 04/21/2022] [Indexed: 11/09/2022] Open
Abstract
In quorum sensing, bacteria secrete or release small molecules into the environment that, once they reach a certain threshold, trigger a behavioural change in the population. As the concentration of these so-called autoinducers is supposed to reflect population density, they were originally assumed to be continuously produced by all cells in a population. However, here we show that in the α-proteobacterium Sinorhizobium meliloti expression of the autoinducer synthase gene is realized in asynchronous stochastic pulses that result from scarcity and, presumably, low binding affinity of the key activator. Physiological cues modulate pulse frequency, and pulse frequency in turn modulates the velocity with which autoinducer levels in the environment reach the threshold to trigger the quorum sensing response. We therefore propose that frequency-modulated pulsing in S. meliloti represents the molecular mechanism for a collective decision-making process in which each cell's physiological state and need for behavioural adaptation is encoded in the pulse frequency with which it expresses the autoinducer synthase gene; the pulse frequencies of all members of the population are then integrated in the common pool of autoinducers, and only once this vote crosses the threshold, the response behaviour is initiated.
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Zhao Z, Wang L, Miao J, Zhang Z, Ruan J, Xu L, Guo H, Zhang M, Qiao W. Regulation of the formation and structure of biofilms by quorum sensing signal molecules packaged in outer membrane vesicles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:151403. [PMID: 34742801 DOI: 10.1016/j.scitotenv.2021.151403] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/30/2021] [Accepted: 10/30/2021] [Indexed: 06/13/2023]
Abstract
Quorum sensing signal molecules can be used to regulate the formation of biofilm, but it has not been reported that outer membrane vesicles (OMVs) can package and mediate signal molecules to regulate biofilm. We isolated and purified OMVs packaged with Pseudomonas quinolone signal (PQS) released by Pseudomonas aeruginosa and studied the effects of OMV-mediated PQS on the formation and structure of biofilms. OMV-mediated PQS promoted the growth of biofilm, and the cells in the biofilm were stretched, deformed and "bridged" with the surrounding cells. Raman spectrometry showed that the structure and components of the extracellular polymeric substances of P. aeruginosa changed; moreover extracellular proteins rather than polysaccharides played the dominant role in the formation of P. aeruginosa biofilms when regulated by OMV-mediated PQS. In the combination biofilm formed by P. aeruginosa and Staphylococcus aureus, the mediation of OMVs enhanced the inhibitory effect of PQS to the growth of S. aureus, resulting a decrease in EPS produced by the two bacteria. OMV-mediated PQS led to changes in the biodiversity, richness and structure of the microbial community in biofilms formed by active sludge. This work reveals the mechanism of OMVs mediated signal molecules regulating biofilm, which lays a new theoretical and practical foundation for guiding the operation of low-level of biofouling MBRs.
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Affiliation(s)
- Zhenqing Zhao
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Lianjie Wang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Jiahui Miao
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Ziyan Zhang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Jingqi Ruan
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Lijie Xu
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - He Guo
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Ming Zhang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Weichuan Qiao
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China.
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13
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Wang R, Zhang W, Ding W, Liang Z, Long L, Wong WC, Qian PY. Profiling Signal Transduction in Global Marine Biofilms. Front Microbiol 2022; 12:768926. [PMID: 35069473 PMCID: PMC8776716 DOI: 10.3389/fmicb.2021.768926] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 11/29/2021] [Indexed: 01/02/2023] Open
Abstract
Microbes use signal transduction systems in the processes of swarming motility, antibiotic resistance, virulence, conjugal plasmid transfer, and biofilm formation. However, the signal transduction systems in natural marine biofilms have hardly been profiled. Here we analyzed signal transduction genes in 101 marine biofilm and 91 seawater microbial metagenomes. The abundance of almost all signal transduction-related genes in biofilm microbial communities was significantly higher than that in seawater microbial communities, regardless of substrate types, locations, and durations for biofilm development. In addition, the dominant source microbes of signal transduction genes in marine biofilms were different from those in seawater samples. Co-occurrence network analysis on signal communication between microbes in marine biofilms and seawater microbial communities revealed potential inter-phyla interactions between microorganisms from marine biofilms and seawater. Moreover, phylogenetic tree construction and protein identity comparison displayed that proteins related to signal transductions from Red Sea biofilms were highly similar to those from Red Sea seawater microbial communities, revealing a possible biological basis of interspecies interactions between surface-associated and free-living microbial communities in a local marine environment. Our study revealed the special profile and enrichment of signal transduction systems in marine biofilms and suggested that marine biofilms participate in intercellular interactions of the local ecosystem where they were seeded.
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Affiliation(s)
- Ruojun Wang
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Weipeng Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Wei Ding
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Zhicong Liang
- Department of Mathematics, Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Lexin Long
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.,Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Wai Chuen Wong
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Pei-Yuan Qian
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
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14
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Quorum Sensing Regulation of Virulence Gene Expression in Vibrio harveyi during its Interaction with Marine Diatom Skeletonema marinoi. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2021. [DOI: 10.22207/jpam.15.4.78] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Communication between species from different kingdoms may be as important as intra-kingdom communication. It has recently been confirmed that co-existing bacteria and phytoplankton in aquatic ecosystems do cross-talk. This study examined the signs of possible cross signalling between V. harveyi, one of the predominant bacterial species of the marine ecosystem and a dominant diatom species, S.marinoi, to understand communication over species borders. It is known that V.harveyi employ quorum sensing for cell-to-cell communication, bioluminescence (luxR), and the regulation of the virulence gene (vhp, chiA). Former studies have also shown, this kind of interactions being disrupted by compounds secreted by a few algal species existing in the aquatic ecosystem. We investigated the QS communication by quantifying the expression levels of virulence regulator luxR and virulence factors metalloprotease (vhp) and chitinase (chiA) in four different V. harveyi strains grown in the presence of S. marinoi strain. Results obtained in this study indicate that quorum sensing was activated in strains of V. harveyi analysed but did not regulate the expressions of vhp and chiA virulence factors. This observation suggests that the existence of S. marinoi did not interfere with the QS behaviour of V. harveyi and its interaction with marine diatom; it may be due to the commensalism relationship.
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15
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Tagele SB, Kim RH, Shin JH. Interactions between Brassica Biofumigants and Soil Microbiota: Causes and Impacts. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:11538-11553. [PMID: 34551253 DOI: 10.1021/acs.jafc.1c03776] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Biofumigation is used to control soil-borne plant diseases, and it has paramount importance to reduce the cost of chemical fumigants. Information about the field control efficacies and impacts of Brassica-based biofumigation (BBF) on soil bacterial and fungal microbiota is scattered in the literature. Therefore, this review summarizes and discusses the nature and the underlying causes of soil bacterial and fungal community dynamics in response to BBF. In addition, the major factors influencing the interaction between a biofumigant and soil microbiota are discussed. The pros and cons of BBF to soil microbiota and the subsequent impacts on sustainable farming practices are also highlighted.
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Affiliation(s)
- Setu Bazie Tagele
- Department of Applied Biosciences, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Ryeong-Hui Kim
- Department of Integrative Biology, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Jae-Ho Shin
- Department of Applied Biosciences, Kyungpook National University, Daegu 41566, Republic of Korea
- Department of Integrative Biology, Kyungpook National University, Daegu 41566, Republic of Korea
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16
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Niggli S, Wechsler T, Kümmerli R. Single-Cell Imaging Reveals That Staphylococcus aureus Is Highly Competitive Against Pseudomonas aeruginosa on Surfaces. Front Cell Infect Microbiol 2021; 11:733991. [PMID: 34513736 PMCID: PMC8426923 DOI: 10.3389/fcimb.2021.733991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/09/2021] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas aeruginosa and Staphylococcus aureus frequently occur together in polymicrobial infections, and their interactions can complicate disease progression and treatment options. While interactions between P. aeruginosa and S. aureus have been extensively described using planktonic batch cultures, little is known about whether and how individual cells interact with each other on solid substrates. This is important because both species frequently colonize surfaces to form aggregates and biofilms in infections. Here, we performed single-cell time-lapse fluorescence microscopy, combined with automated image analysis, to describe interactions between P. aeruginosa PAO1 with three different S. aureus strains (Cowan I, 6850, JE2) during microcolony growth on agarose surfaces. While P. aeruginosa is usually considered the dominant species, we found that the competitive balance tips in favor of S. aureus on surfaces. We observed that all S. aureus strains accelerated the onset of microcolony growth in competition with P. aeruginosa and significantly compromised P. aeruginosa growth prior to physical contact. Upon direct contact, JE2 was the most competitive S. aureus strain, simply usurping P. aeruginosa microcolonies, while 6850 was the weakest competitor itself suppressed by P. aeruginosa. Moreover, P. aeruginosa reacted to the assault of S. aureus by showing increased directional growth and expedited expression of quorum sensing regulators controlling the synthesis of competitive traits. Altogether, our results reveal that quantitative single-cell live imaging has the potential to uncover microbial behaviors that cannot be predicted from batch culture studies, and thereby contribute to our understanding of interactions between pathogens that co-colonize host-associated surfaces during polymicrobial infections.
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Affiliation(s)
- Selina Niggli
- Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland
| | | | - Rolf Kümmerli
- Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland
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17
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Chahande AM, Lathigara D, Prabhune AA, Devi RN. Red fluorescent ultra-small gold nanoclusters functionalized with signal molecules to probe specificity in quorum sensing receptors in gram-negative bacteria. Arch Microbiol 2021; 203:4293-4301. [PMID: 34109439 DOI: 10.1007/s00203-021-02338-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 04/13/2021] [Accepted: 04/17/2021] [Indexed: 02/03/2023]
Abstract
Ultra-small (size < 2 nm) gold nanoclusters (AuNCs) are used as fluorescent probes which have excellent applications in bioimaging and sensing due to their emission in visible and NIR spectral region. Here, this property is exploited for understanding the quorum sensing phenomenon in bacteria which is regulated by signal molecules which are specific to various species. AuNCs are then functionalized with the signal molecules, Acyl Homoserine Lactones (AHL) of varying carbon chain length, C-6, C-8, and C-12 without 3rd C modification, to sense different strains of gram-negative bacteria i.e., Escherichia coli, Cronobacter sakazakii and Pseudomonas aeruginosa. In the concentration employed, selectivity to a limited extent is observed between the three Gram-negative bacteria tested. E. coli showed emission with all the AHL conjugates and P. aeruginosa did not interact with any of the three conjugates, whereas C. sakazakii showed specificity to C-8AHL. This is probably due to selectivity for cognate AHL molecules of appropriate concentrations.
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Affiliation(s)
- Anurag M Chahande
- Catalysis and Inorganic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, 201002, India
| | - Disha Lathigara
- Biochemical Science Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
| | - Asmita A Prabhune
- Biochemical Science Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India.
| | - R Nandini Devi
- Catalysis and Inorganic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India.
- Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, 201002, India.
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18
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Chamberlain CA, Hatch M, Garrett TJ. Extracellular Vesicle Analysis by Paper Spray Ionization Mass Spectrometry. Metabolites 2021; 11:metabo11050308. [PMID: 34065030 PMCID: PMC8151837 DOI: 10.3390/metabo11050308] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/23/2021] [Accepted: 05/06/2021] [Indexed: 12/29/2022] Open
Abstract
Paper spray ionization mass spectrometry (PSI-MS) is a direct MS analysis technique with several reported bacterial metabolomics applications. As with most MS-based bacterial studies, all currently reported PSI-MS bacterial analyses have focused on the chemical signatures of the cellular unit. One dimension of the bacterial metabolome that is often lost in such analyses is the exometabolome (extracellular metabolome), including secreted metabolites, lipids, and peptides. A key component of the bacterial exometabolome that is gaining increased attention in the microbiology and biomedical communities is extracellular vesicles (EVs). These excreted structures, produced by cells in all domains of life, contain a variety of biomolecules responsible for a wide array of cellular functions, thus representing a core component of the bacterial secreted metabolome. Although previously examined using other MS approaches, no reports currently exist for a PSI-MS analysis of bacterial EVs, nor EVs from any other organism (exosomes, ectosomes, etc.). PSI-MS holds unique analytical strengths over other commonly used MS platforms and could thus provide an advantageous approach to EV metabolomics. To address this, we report a novel application representing, to our knowledge, the first PSI-MS analysis of EVs from any organism (using the human gut resident Oxalobacter formigenes as the experimental model, a bacterium whose EVs were never previously investigated). In this report, we show how we isolated and purified EVs from bacterial culture supernatant by EV-specific affinity chromatography, confirmed and characterized these vesicles by nanoparticle tracking analysis, analyzed the EV isolate by PSI-MS, and identified a panel of EV-derived metabolites, lipids, and peptides. This work serves as a pioneering study in the field of MS-based EV analysis and provides a new, rapid, sensitive, and economical approach to EV metabolomics.
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19
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Cyclodextrin-mediated quorum quenching in the Aliivibrio fischeri bioluminescence model system – Modulation of bacterial communication. Int J Pharm 2021; 594:120150. [DOI: 10.1016/j.ijpharm.2020.120150] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 11/28/2020] [Accepted: 12/01/2020] [Indexed: 02/06/2023]
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20
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Igiehon NO, Babalola OO, Cheseto X, Torto B. Effects of rhizobia and arbuscular mycorrhizal fungi on yield, size distribution and fatty acid of soybean seeds grown under drought stress. Microbiol Res 2021; 242:126640. [PMID: 33223380 DOI: 10.1016/j.micres.2020.126640] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 09/04/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023]
Abstract
Soybean (Glycine max L.) is among the most economically important legumes that provide more than 1/4 of food (for man) and animal feed. However, its yield is comparatively low, most especially under drought stress. The aim of this study therefore was to assess the ability of Rhizobium spp. and mycorrhizal fungi to enhance the yield, seed size and fatty acid content of soybean grown under semi-arid environment. Rhizobium sp. strain R1 was found to possess nitrogen-fixing gene coniferyl aldehyde dehydrogenase function while Rhizobium cellulosilyticum strain R3 was found to have nitrogen-fixing genes cysteine desulfurase SufS and cysteine desulfurase IscS activity. Soybean (Glycine max L) seeds inoculated with Rhizobium spp. and mycorrhizal fungi were cultivated in soil exposed to drought stress. Rhizobium spp. inoculation and mycorrhization alleviate drought stress and increase yield, size and fat content of soybean seeds. This increase in the aboveground parameters was accompanied with an increase in belowground mycorrhizal spore number, percentage root mycorrhization and aboveground shoot relative water content (RWC) in the dually inoculated (R1 + R3MY) soybean plants. In particular, the dually inoculated (R1 + R3MY) soybean plants revealed 34.3 g fresh weight, 15.1 g dry weight and soybean plants singly inoculated with Rhizobium sp. strain R1 (R1) produced more large seeds with 12.03 g dry weight. The non-inoculated (control) seeds contained a higher percentage of moisture content compared to the microbially amended seeds while seeds co-inoculated with Rhizobium cellulosilyticum strain R3 and mycorrhizal consortium revealed the highest percent (8.4 %) of fat. Several fatty acids that are of significant health benefits to humans were observed in the soybean seeds. In order to gain insights into the bacterial communities of rhizospheric soil collected at different stages of soybean growth, class-based Heat-map analysis was performed on the Miseq sequenced data. The core bacteria that were found in the rhizospheric soil were Verrumicrobia, Proteobacteria, Gemmatimonadetes, Firmicutes, Cyanobacteria, Chloroflexi, Bacteroidetes, Actinobacteria, Acidobacteria, Planctomycetes, Deinococcus thermus and Nitrospira suggesting that the rhizobia and fungi used in this study can also improve soil microbial diversity.
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Affiliation(s)
- Nicholas O Igiehon
- Food Security and Safety Niche, Faculty of Natural and Agricultural Sciences, Private Mail Bag X2046, North-West University, Mmabatho 2735, South Africa
| | - Olubukola O Babalola
- Food Security and Safety Niche, Faculty of Natural and Agricultural Sciences, Private Mail Bag X2046, North-West University, Mmabatho 2735, South Africa.
| | - Xavier Cheseto
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
| | - Baldwyn Torto
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
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21
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Boopathi S, Liu D, Jia AQ. Molecular trafficking between bacteria determines the shape of gut microbial community. Gut Microbes 2021; 13:1959841. [PMID: 34455923 PMCID: PMC8432619 DOI: 10.1080/19490976.2021.1959841] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 07/08/2021] [Accepted: 07/14/2021] [Indexed: 02/04/2023] Open
Abstract
Complex inter-bacterial interactions largely influence the structure and function of the gut microbial community. Though several host-associated phenomena have often been shown to be involved in the stability, structure, and function of the gut microbial community, the implication of contact-dependent and contact-independent inter-bacterial interactions has been overlooked. Such interactions are tightly governed at multiple layers through several extracellular organelles, including contact-dependent inhibition (CDI), nanotubes, type VI secretion system (T6SS), and membrane vesicles (MVs). Recent advancements in molecular techniques have revealed that such extracellular organelles function beyond exhibiting competitive behavior and are also involved in manifesting cooperative behaviors. Cooperation between bacteria occurs through the sharing of several beneficial molecules including nucleic acids, proteins, metabolites, and nutrients among the members of the community, while competition occurs by means of multiple toxins. Intrinsic coordination between contact-dependent and contact-independent mechanisms collectively provides a fitness advantage and increased colonization resistance to the gut microbiota, where molecular trafficking plays a key role. This review is intended to provide a comprehensive view of the salient features of the different bacterial interactions and to highlight how microbiota deploy multifaceted organelles, for exerting both cooperative and competitive behaviors. We discuss the current knowledge of bacterial molecular trafficking and its impact on shaping the gut microbial community.
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Affiliation(s)
- Seenivasan Boopathi
- School of Life and Pharmaceutical Sciences, Key Laboratory of Tropical Biological Resources of Ministry Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Danrui Liu
- School of Life and Pharmaceutical Sciences, Key Laboratory of Tropical Biological Resources of Ministry Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Ai-Qun Jia
- School of Life and Pharmaceutical Sciences, Key Laboratory of Tropical Biological Resources of Ministry Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
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22
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Alnahhas RN, Sadeghpour M, Chen Y, Frey AA, Ott W, Josić K, Bennett MR. Majority sensing in synthetic microbial consortia. Nat Commun 2020; 11:3659. [PMID: 32694598 PMCID: PMC7374166 DOI: 10.1038/s41467-020-17475-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 06/25/2020] [Indexed: 01/26/2023] Open
Abstract
As synthetic biocircuits become more complex, distributing computations within multi-strain microbial consortia becomes increasingly beneficial. However, designing distributed circuits that respond predictably to variation in consortium composition remains a challenge. Here we develop a two-strain gene circuit that senses and responds to which strain is in the majority. This involves a co-repressive system in which each strain produces a signaling molecule that signals the other strain to down-regulate production of its own, orthogonal signaling molecule. This co-repressive consortium links gene expression to ratio of the strains rather than population size. Further, we control the cross-over point for majority via external induction. We elucidate the mechanisms driving these dynamics by developing a mathematical model that captures consortia response as strain fractions and external induction are varied. These results show that simple gene circuits can be used within multicellular synthetic systems to sense and respond to the state of the population.
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Affiliation(s)
| | - Mehdi Sadeghpour
- Department of Biosciences, Rice University, Houston, TX, USA
- Department of Mathematics, University of Houston, Houston, TX, USA
| | - Ye Chen
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Alexis A Frey
- Department of Biosciences, Rice University, Houston, TX, USA
| | - William Ott
- Department of Mathematics, University of Houston, Houston, TX, USA
| | - Krešimir Josić
- Department of Mathematics, University of Houston, Houston, TX, USA
- Department of Biology and Biochemistry, University of Houston, Houston, TX, USA
| | - Matthew R Bennett
- Department of Biosciences, Rice University, Houston, TX, USA.
- Department of Bioengineering, Rice University, Houston, TX, USA.
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23
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Effects of Selected Functional Bacteria on Maize Growth and Nutrient Use Efficiency. Microorganisms 2020; 8:microorganisms8060854. [PMID: 32517011 PMCID: PMC7356773 DOI: 10.3390/microorganisms8060854] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 01/09/2023] Open
Abstract
Plant growth-promoting rhizobacteria (PGPR), which include isolates from genera Paraburkholderia, Burkholderia and Serratia, have received attention due to their numerous plant growth-promoting mechanisms such as their ability to solubilize insoluble phosphates and nitrogen-fixation. However, there is a dearth of information on the potential plant growth-promoting effects of these three groups of bacteria on non-legumes such as maize. This study determined the influences of the aforementioned strains on soil properties, maize growth, nutrient uptake and nutrient use efficiency. A pot trial using maize as a test crop was done using a randomized complete block design with 7 treatments each replicated 7 times. The treatments used in this study were: Control (no fertilizer), chemical fertilizer (CF), organic-chemical fertilizers combination without inoculum (OCF) and with inocula consisting of single strains [cellulolytic bacteria (TC), organic fertilizer and chemical fertilizer with N-fixing bacteria (TN), organic fertilizer and chemical fertilizer with P-solubilizing bacteria (TP)) and three-strain inocula (TCNP), respectively. The variables measured included plant growth and nutrient content, soil nutrient content and functional rhizospheric bacterial populations. Paraburkholderia nodosa NB1 and Burkholderia cepacia PB3 showed comparable effects on maize biomass and also improved N and P use efficiencies when compared to full chemical fertilization. Nitrogen-fixing rhizobacteria had a positive effect on above-ground biomass of maize. Paraburkholderia nodosa NB1 improved soil total C and organic matter contents, besides being the only bacterial treatment that improved K use efficiency compared to OCF. The results suggest that P. nodosa NB1 and B. cepacia PB3 have potential usage in bio-fertilizers. In contrast, treatments with Serratia nematodiphila C46d and consortium strains showed poorer maize nutrient uptake and use efficiency than the other single strain treatments. Bacterial treatments generally showed comparable or higher overall N and P use efficiencies than full chemical fertilization. These findings suggest that at least half the amounts of N and P fertilizers could be reduced through the use of combined fertilization together with beneficial bacteria.
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24
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Wu S, Liu J, Liu C, Yang A, Qiao J. Quorum sensing for population-level control of bacteria and potential therapeutic applications. Cell Mol Life Sci 2020; 77:1319-1343. [PMID: 31612240 PMCID: PMC11104945 DOI: 10.1007/s00018-019-03326-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/13/2019] [Accepted: 09/30/2019] [Indexed: 02/07/2023]
Abstract
Quorum sensing (QS), a microbial cell-to-cell communication process, dynamically regulates a variety of metabolism and physiological activities. In this review, we provide an update on QS applications based on autoinducer molecules including acyl-homoserine lactones (AHLs), auto-inducing peptides (AIPs), autoinducer 2 (AI-2) and indole in population-level control of bacteria, and highlight the potential in developing novel clinical therapies. We summarize the development in the combination of various genetic circuits such as genetic oscillators, toggle switches and logic gates with AHL-based QS devices in Gram-negative bacteria. An overview is then offered to the state-of-the-art of much less researched applications of AIP-based QS devices with Gram-positive bacteria, followed by a review of the applications of AI-2 and indole based QS for interspecies communication among microbial communities. Building on these general-purpose QS applications, we highlight the disruptions and manipulations of QS devices as potential clinical therapies for diseases caused by biofilm formation, antibiotic resistance and the phage invasion. The last part of reviewed literature is dedicated to mathematical modelling for QS applications. Finally, the key challenges and future perspectives of QS applications in monoclonal synthetic biology and synthetic ecology are discussed.
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Affiliation(s)
- Shengbo Wu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Jiaheng Liu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
- Key Laboratory of Systems Bioengineering, Ministry of Education (Tianjin University), Tianjin, 300072, China
| | - Chunjiang Liu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Aidong Yang
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK.
| | - Jianjun Qiao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China.
- Key Laboratory of Systems Bioengineering, Ministry of Education (Tianjin University), Tianjin, 300072, China.
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Coggan JS, Keller D, Markram H, Schürmann F, Magistretti PJ. Excitation states of metabolic networks predict dose-response fingerprinting and ligand pulse phase signalling. J Theor Biol 2020; 487:110123. [PMID: 31866398 DOI: 10.1016/j.jtbi.2019.110123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/08/2019] [Accepted: 12/16/2019] [Indexed: 12/30/2022]
Abstract
With a computational model of energy metabolism in an astrocyte, we show how a system of enzymes in a cascade can act as a functional unit of interdependent reactions, rather than merely a series of independent reactions. These systems may exist in multiple states, depending on the level of stimulation, and the effects of substrates at any point will depend on those states. Response trajectories of metabolites downstream from cAMP-stimulated glycogenolysis exhibit a host of non-linear dynamical response characteristics including hysteresis and response envelopes. Dose-dependent phase transitions predict a novel intracellular signalling mechanism and suggest a theoretical framework that could be relevant to single cell information processing, drug discovery or synthetic biology. Ligands may produce unique dose-response fingerprints depending on the state of the system, allowing selective output tuning. We conclude with the observation that state- and dose-dependent phase transitions, what we dub "ligand pulses" (LPs), may carry information and resemble action potentials (APs) generated from excitatory postsynaptic potentials. In our model, the relevant information from a cAMP-dependent glycolytic cascade in astrocytes could reflect the level of neuromodulatory input that signals an energy demand threshold. We propose that both APs and LPs represent specialized cases of molecular phase signalling with a common evolutionary root.
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Affiliation(s)
- Jay S Coggan
- Blue Brain Project, École Polytechnique Fédérale de Lausanne (EPFL), Geneva CH-1202, Switzerland.
| | - Daniel Keller
- Blue Brain Project, École Polytechnique Fédérale de Lausanne (EPFL), Geneva CH-1202, Switzerland.
| | - Henry Markram
- Blue Brain Project, École Polytechnique Fédérale de Lausanne (EPFL), Geneva CH-1202, Switzerland.
| | - Felix Schürmann
- Blue Brain Project, École Polytechnique Fédérale de Lausanne (EPFL), Geneva CH-1202, Switzerland.
| | - Pierre J Magistretti
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
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Barnier C, Clerissi C, Lami R, Intertaglia L, Lebaron P, Grimaud R, Urios L. Description of Palleronia rufa sp. nov., a biofilm-forming and AHL-producing Rhodobacteraceae, reclassification of Hwanghaeicola aestuarii as Palleronia aestuarii comb. nov., Maribius pontilimi as Palleronia pontilimi comb. nov., Maribius salinus as Palleronia salina comb. nov., Maribius pelagius as Palleronia pelagia comb. nov. and emended description of the genus Palleronia. Syst Appl Microbiol 2020; 43:126018. [DOI: 10.1016/j.syapm.2019.126018] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 07/22/2019] [Accepted: 07/26/2019] [Indexed: 12/15/2022]
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Ueno T, Fischer JT, Boon EM. Nitric Oxide Enters Quorum Sensing via the H-NOX Signaling Pathway in Vibrio parahaemolyticus. Front Microbiol 2019; 10:2108. [PMID: 31620101 PMCID: PMC6759604 DOI: 10.3389/fmicb.2019.02108] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/27/2019] [Indexed: 12/29/2022] Open
Abstract
Nitric oxide (NO) plays a major role in the regulation of mammalian biological functions. In recent years, NO has also been implicated in bacterial life cycles, including in the regulation of biofilm formation, and the metabolism of the bacterial second messenger signaling molecule cyclic-di-GMP. In a previous study, we reported the discovery of an NO-responsive quorum sensing (QS) circuit in Vibrio harveyi. Here, we characterize the homologous QS pathway in Vibrio parahaemolyticus. Spectroscopic analysis shows V. parahaemolyticus H-NOX is an NO sensory protein that binds NO in 5/6-coordinated mixed manner. Further, we demonstrate that through ligation to H-NOX, NO inhibits the autophosphorylation activity of an H-NOX-associated histidine kinase (HqsK; H-NOX-associated quorum sensing kinase) that transfers phosphate to the Hpt (histidine-containing phosphotransfer protein) protein LuxU. Indeed, among the three Hpt proteins encoded by V. parahaemolyticus, HqsK transfers phosphate only to the QS-associated phosphotransfer protein LuxU. Finally, we show that NO promotes transcription of the master quorum sensing regulatory gene opaR at low cell density.
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Affiliation(s)
- Takahiro Ueno
- Department of Chemistry, Stony Brook University, Stony Brook, NY, United States
| | - Jonathan T. Fischer
- Department of Chemistry, Stony Brook University, Stony Brook, NY, United States
| | - Elizabeth M. Boon
- Department of Chemistry, Stony Brook University, Stony Brook, NY, United States
- Institute of Chemical Biology & Drug Discovery, Stony Brook University, Stony Brook, NY, United States
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28
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Chen H, Li A, Cui C, Ma F, Cui D, Zhao H, Wang Q, Ni B, Yang J. AHL-mediated quorum sensing regulates the variations of microbial community and sludge properties of aerobic granular sludge under low organic loading. ENVIRONMENT INTERNATIONAL 2019; 130:104946. [PMID: 31252169 DOI: 10.1016/j.envint.2019.104946] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/27/2019] [Accepted: 06/19/2019] [Indexed: 06/09/2023]
Abstract
Aerobic granular sludge (AGS) is promising in wastewater treatment. However, the formation and existence of AGS under low organic loading rate (OLR) is still not fully understood due to a knowledge gap in the variations and correlations of N-acyl-homoserine lactones (AHLs), the microbial community, extracellular polymeric substances (EPS) and other physiochemical granule properties. This study comprehensively investigated the AHL-mediated quorum sensing (QS) and microbial community characters in the AGS fed with ammonium-rich wastewater under a low OLR of 0.15 kg COD (m3 d)-1. The results showed that the AGS appeared within 90 days, and the size of mature granules was over 700 μm with strong settleability and ammonium removal performance. More tightly-bound extracellular polysaccharide and tightly-bound extracelluar protein were produced in the larger AGS. C10-HSL and C12-HSL gradually became dominant in sludge, and short-chain AHLs dominated in water. EPS producers and autotrophic nitrifiers were successfully retained in the AGS under low OLR. AHL-mediated QS utilized C10-HSL, C12-HSL and 3OC6-HSL as the critical AHLs to regulate the TB-EPS in aerobic granulation, and autotrophic nitrifiers may perform interspecific communication with C10-HSL. The correlations of bacterial genera with AGS properties and AHLs were complex due to the dynamic fluctuations of microbial composition and other variable factors in the mixed-culture system. These findings confirmed the participation of AHL-mediated QS in the regulation of microbial community characters and AGS properties under low OLR, which may provide guidance for the operation of AGS systems under low OLR from a microbiological viewpoint.
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Affiliation(s)
- Han Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China
| | - Ang Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China.
| | - Chongwei Cui
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China
| | - Fang Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China.
| | - Di Cui
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China; Research Center on Life Sciences and Environmental Sciences, Harbin University of Commerce, Harbin 150076, People's Republic of China
| | - Heping Zhao
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Qilin Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Bingjie Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Jixian Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China
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Xiao Y, Yaohari H, Zhou Z, Sze CC, Stuckey DC. Autoinducer-2-mediated quorum sensing partially regulates the toxic shock response of anaerobic digestion. WATER RESEARCH 2019; 158:94-105. [PMID: 31022531 DOI: 10.1016/j.watres.2019.04.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
This study discovered a strong correlation between the autoinducer-2 (AI-2)-mediated quorum sensing (QS) with the performance of a submerged anaerobic membrane bioreactor during its recovery from a pentachlorophenol (PCP) shock: a decrease in AI-2 levels coincided with a reduction in volatile fatty acid concentrations, and corresponded significantly to a decrease in the relative abundance of Firmicutes, and to an increase in the relative abundance of Bacteroidetes and Synergistetes. Further batch experiments with the addition of an AI-2-regulating Escherichia coli mutant culture showed that a reduction in AI-2 levels resulted in the highest biogas production rate during a PCP shock. In contrast, an increase in AI-2 levels via addition of the E. coli wild type strain or an AI-2 precursor showed no obvious effects on biogas production. These results suggest that the AI-2 level in anaerobic sludge was governed primarily by Firmicutes, and the AI-2-mediated QS partially regulates the toxic shock response of anaerobic sludge via tuning the activities of Firmicutes and Synergistetes. A decrease in the AI-2 level might reduce acetogenesis and favor hydrogenotrophic methanogenesis, thus resulting in less VFA accumulation and higher methane production during the PCP shock. This study is the first of this type that exploits the role of quorum sensing in the toxic shock response of anaerobic sludge; it demonstrates a novel approach to shortening the recovery period of anaerobic processes via manipulating the AI-2-mediated QS.
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Affiliation(s)
- Yeyuan Xiao
- Department of Civil and Environmental Engineering, Shantou University, 515063, China; Advanced Environmental Biotechnology Centre (AEBC), Nanyang Environment and Water Research Centre (NEWRI), Nanyang Technological University, 637141, Singapore
| | - Hazarki Yaohari
- Advanced Environmental Biotechnology Centre (AEBC), Nanyang Environment and Water Research Centre (NEWRI), Nanyang Technological University, 637141, Singapore
| | - Zhongbo Zhou
- Advanced Environmental Biotechnology Centre (AEBC), Nanyang Environment and Water Research Centre (NEWRI), Nanyang Technological University, 637141, Singapore
| | - Chun Chau Sze
- Advanced Environmental Biotechnology Centre (AEBC), Nanyang Environment and Water Research Centre (NEWRI), Nanyang Technological University, 637141, Singapore; School of Biological Sciences, Nanyang Technological University, 637551, Singapore
| | - David C Stuckey
- Advanced Environmental Biotechnology Centre (AEBC), Nanyang Environment and Water Research Centre (NEWRI), Nanyang Technological University, 637141, Singapore; Department of Chemical Engineering, Imperial College London, SW7 2AZ, UK.
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30
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Do H, Makthal N, VanderWal AR, Saavedra MO, Olsen RJ, Musser JM, Kumaraswami M. Environmental pH and peptide signaling control virulence of Streptococcus pyogenes via a quorum-sensing pathway. Nat Commun 2019; 10:2586. [PMID: 31197146 PMCID: PMC6565748 DOI: 10.1038/s41467-019-10556-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 05/14/2019] [Indexed: 12/20/2022] Open
Abstract
Bacteria control gene expression in concert with their population density by a process called quorum sensing, which is modulated by bacterial chemical signals and environmental factors. In the human pathogen Streptococcus pyogenes, production of secreted virulence factor SpeB is controlled by a quorum-sensing pathway and environmental pH. The quorum-sensing pathway consists of a secreted leaderless peptide signal (SIP), and its cognate receptor RopB. Here, we report that the SIP quorum-sensing pathway has a pH-sensing mechanism operative through a pH-sensitive histidine switch located at the base of the SIP-binding pocket of RopB. Environmental acidification induces protonation of His144 and reorganization of hydrogen bonding networks in RopB, which facilitates SIP recognition. The convergence of two disparate signals in the SIP signaling pathway results in induction of SpeB production and increased bacterial virulence. Our findings provide a model for investigating analogous crosstalk in other microorganisms.
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Affiliation(s)
- Hackwon Do
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Nishanth Makthal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Arica R VanderWal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Matthew Ojeda Saavedra
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Randall J Olsen
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, 10021, USA
| | - James M Musser
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, 10021, USA
| | - Muthiah Kumaraswami
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA.
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA.
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31
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Antunes J, Leão P, Vasconcelos V. Marine biofilms: diversity of communities and of chemical cues. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:287-305. [PMID: 30246474 DOI: 10.1111/1758-2229.12694] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 09/14/2018] [Indexed: 06/08/2023]
Abstract
Surfaces immersed in seawater are rapidly colonized by various microorganisms, resulting in the formation of heterogenic marine biofilms. These communities are known to influence the settlement of algae spores and invertebrate larvae, triggering a succession of fouling events, with significant environmental and economic impacts. This review covers recent research regarding the differences in composition of biofilms isolated from different artificial surface types and the influence of environmental factors on their formation. One particular phenomenon - bacterial quorum sensing (QS) - allows bacteria to coordinate swarming, biofilm formation among other phenomena. Some other marine biofilm chemical cues are believed to modulate the settlement and the succession of macrofouling organisms, and they are also reviewed here. Finally, since the formation of a marine biofilm is considered to be an initial, QS-dependent step in the development of marine fouling events, QS inhibition is discussed on its potential as a tool for antibiofouling control in marine settings.
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Affiliation(s)
- Jorge Antunes
- CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Av. General Norton de Matos, s/n 4450-208, Matosinhos, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre 4069-007, Porto, Portugal
| | - Pedro Leão
- CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Av. General Norton de Matos, s/n 4450-208, Matosinhos, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre 4069-007, Porto, Portugal
| | - Vitor Vasconcelos
- CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Av. General Norton de Matos, s/n 4450-208, Matosinhos, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre 4069-007, Porto, Portugal
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Zhao J, Li X, Hou X, Quan C, Chen M. Widespread Existence of Quorum Sensing Inhibitors in Marine Bacteria: Potential Drugs to Combat Pathogens with Novel Strategies. Mar Drugs 2019; 17:md17050275. [PMID: 31072008 PMCID: PMC6562741 DOI: 10.3390/md17050275] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 04/28/2019] [Accepted: 04/29/2019] [Indexed: 12/22/2022] Open
Abstract
Quorum sensing (QS) is a phenomenon of intercellular communication discovered mainly in bacteria. A QS system consisting of QS signal molecules and regulatory protein components could control physiological behaviors and virulence gene expression of bacterial pathogens. Therefore, QS inhibition could be a novel strategy to combat pathogens and related diseases. QS inhibitors (QSIs), mainly categorized into small chemical molecules and quorum quenching enzymes, could be extracted from diverse sources in marine environment and terrestrial environment. With the focus on the exploitation of marine resources in recent years, more and more QSIs from the marine environment have been investigated. In this article, we present a comprehensive review of QSIs from marine bacteria. Firstly, screening work of marine bacteria with potential QSIs was concluded and these marine bacteria were classified. Afterwards, two categories of marine bacteria-derived QSIs were summarized from the aspects of sources, structures, QS inhibition mechanisms, environmental tolerance, effects/applications, etc. Next, structural modification of natural small molecule QSIs for future drug development was discussed. Finally, potential applications of QSIs from marine bacteria in human healthcare, aquaculture, crop cultivation, etc. were elucidated, indicating promising and extensive application perspectives of QS disruption as a novel antimicrobial strategy.
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Affiliation(s)
- Jing Zhao
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian 116600, China.
- College of Life Science, Dalian Minzu University, Dalian 116600, China.
| | - Xinyun Li
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian 116600, China.
- College of Life Science, Dalian Minzu University, Dalian 116600, China.
| | - Xiyan Hou
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian 116600, China.
- College of Life Science, Dalian Minzu University, Dalian 116600, China.
| | - Chunshan Quan
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian 116600, China.
- College of Life Science, Dalian Minzu University, Dalian 116600, China.
| | - Ming Chen
- School of Biological Engineering, Dalian Polytechnic University, Dalian 116600, China.
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Li Y, Zhao J, Quan C, Jin L, Xu Y, Chen M. Production, characterization, and powder preparation of quorum quenching acylase AiiO for pathogen control. Prep Biochem Biotechnol 2019; 49:151-157. [PMID: 30712466 DOI: 10.1080/10826068.2018.1550657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Acylase AiiO is a novel quorum quenching enzyme with a broad substrate spectrum of acyl-homoserine lactones (AHLs) and has promising prospects in pathogen control. In this work, acylase AiiO production by a recombinant E. coli strain and its characterization were investigated; the acylase powder was further prepared and evaluated for effectiveness. A strategy of auto-induction combined with temperature regulation was developed to improve AiiO production. For the soluble AiiO protein in the cells, maximum production of 214.3 ± 9.4 mg/L was obtained in the fermenter. The purified acylase displayed an obvious AHL-degrading specific activity of 19.2 ± 0.56 U/mg. Sucrose, as the protective agent, maintained good stability of the acylase powder, in which the acylase remained 89.6 and 71.9% of its initial specific activity after storage at 4 °C for 3 and 6 months, respectively. The acylase powder could prominently decrease the expression levels of virulence-related factors of Pseudomonas aeruginosa. Based on the high-yield production and effective powder preparation, the quorum quenching acylase AiiO has the potential to be used in the clinical treatments of pathogenic infections.
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Affiliation(s)
- Yue Li
- a School of Biological Engineering, Dalian Polytechnic University , Dalian , China
| | - Jing Zhao
- b Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University) , Ministry of Education , Dalian , China.,c College of Life Science , Dalian Minzu University , Dalian , China
| | - Chunshan Quan
- b Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University) , Ministry of Education , Dalian , China.,c College of Life Science , Dalian Minzu University , Dalian , China
| | - Liming Jin
- b Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University) , Ministry of Education , Dalian , China.,c College of Life Science , Dalian Minzu University , Dalian , China
| | - Yongbin Xu
- b Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University) , Ministry of Education , Dalian , China.,c College of Life Science , Dalian Minzu University , Dalian , China
| | - Ming Chen
- a School of Biological Engineering, Dalian Polytechnic University , Dalian , China
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Srinivasarao S, Nandikolla A, Nizalapur S, Yu TT, Pulya S, Ghosh B, Murugesan S, Kumar N, Chandra Sekhar KVG. Design, synthesis and biological evaluation of 1,2,3-triazole based 2-aminobenzimidazoles as novel inhibitors of LasR dependent quorum sensing in Pseudomonas aeruginosa. RSC Adv 2019; 9:29273-29292. [PMID: 35528444 PMCID: PMC9071802 DOI: 10.1039/c9ra05059k] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 09/06/2019] [Indexed: 11/26/2022] Open
Abstract
Bacteria regulate their phenotype, growth and population via a signalling pathway known as quorum sensing. In this process, bacteria produce signalling molecules (autoinducers) to recognize their population density. Inhibiting this quorum sensing signalling pathway is one of the potential methods to treat bacterial infection. 2-Aminobenimdazoles are reported to be the strongest inhibitors of quorum sensing against wild-type P. aeruginosa. 1,2,3-Triazole based acyl homoserine lactones are found to be good inhibitors of the quorum sensing LasR receptor. Hence, in our current study, forty 1,2,3-triazole based 2-aminobenzimdazoles were synthesized and characterized using IR, NMR, MS and elemental analysis. A single crystal was developed for N-(1H-benzo[d]imidazol-2-yl)-2-(4-nonyl-1H-1,2,3-triazol-1-yl)acetamide (6d). All final compounds were screened for in vitro quorum sensing inhibitory activity against Pseudomonas aeruginosa. The quorum sensing inhibitory activity was determined in the LasR expressing P. aeruginosa MH602 reporter strain by measuring green fluorescent protein production. Among the title compounds, N-(1H-benzo[d]imidazol-2-yl)-2-(4-(4-chlorophenyl)-1H-1,2,3-triazol-1-yl)acetamide (6i) exhibited good quorum sensing inhibitory activity of 64.99% at 250 μM. N-(1H-Benzo[d]imidazol-2-yl)-2-(4-(4-nitrophenyl)-1H-1,2,3-triazol-1-yl)acetamide (6p) exhibited the most promising quorum sensing inhibitory activity with 68.23, 67.10 and 63.67% inhibition at 250, 125 and 62.5 μM, respectively. N-(1H-Benzo[d]imidazol-2-yl)-2-(4-(4-(trifluoromethyl)phenyl)-1H-1,2,3-triazol-1-yl)acetamide (6o) and N-(5,6-dimethyl-1H-benzo[d]imidazol-2-yl)-2-(4-(4-(trifluoromethyl)phenyl)-1H-1,2,3-triazol-1-yl)acetamide (7l) also exhibited 64.25% and 65.80% quorum sensing inhibition at 250 μM. Compound 6p, the most active quorum sensing inhibitor, also displayed low cytotoxicity at the tested concentrations (25, 50 and 100 μM) against normal human embryonic kidney cell lines. Finally, a docking study using Schrodinger Glide elucidated the possible putative binding mode of the significantly active compound 6p at the active site of the target LasR receptor (PDB ID: 2UV0). Out of 40 benzimdazoles, 12 exhibited potent QSI activity against P. aeruginosa6p, most active QSI is docked to LasR and is less toxic against HEK 293 cell line.![]()
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Affiliation(s)
| | | | | | | | - Sravani Pulya
- Department of Pharmacy
- Birla Institute of Technology and Science
- Hyderabad-500078
- India
| | - Balaram Ghosh
- Department of Pharmacy
- Birla Institute of Technology and Science
- Hyderabad-500078
- India
| | - Sankaranarayanan Murugesan
- Medicinal Chemistry Research Laboratory
- Department of Pharmacy
- Birla Institute of Technology and Science
- Pilani
- India
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Nowacka M, Rygała A, Kręgiel D, Kowalewska A. Poly(silsesquioxanes) and poly(siloxanes) grafted with N-acetylcysteine for eradicating mature bacterial biofilms in water environment. Colloids Surf B Biointerfaces 2018; 172:627-634. [PMID: 30223245 DOI: 10.1016/j.colsurfb.2018.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/27/2018] [Accepted: 09/07/2018] [Indexed: 11/19/2022]
Abstract
Bacteria adapt to their living environment forming organised biofilms. The survival strategy makes them more resistant to disinfectants, which results in acute biofilm-caused infections, secondary water pollution by biofilm metabolites and bio-corrosion. New, efficient and environmentally friendly strategies must be developed to solve this problem. Water soluble N-acetyl derivative of L-cysteine (NAC) is a non-toxic compound of mucolytic and bacteriostatic properties that can interfere with the formation of biofilms. However, it can also be a source of C and N for undesired microorganisms, as well as a reason for some adverse human health effects. Consequently, novel procedures are required, that would decrease the take-up of NAC but not reduce its antibacterial properties. We have grafted N-acetyl-l-cysteine onto linear poly(vinylsilsesquioxanes) and poly(methylvinylsiloxanes) via thiol-ene addition. Antibacterial activity of the obtained hybrid materials (respectively, NAC-Si-1 and NAC-Si-2) was determined against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus strains. Native NAC inhibited growth of planktonic cells for the tested bacteria at concentration 0.25% w/v. Inhibition with equivalent solutions of the polymer derivatives was less effective due to the lack of SH groups. However, the tested polymers proved to be quite effective in eradication of mature biofilms. Treatment with 1% w/v emulsions of the hybrid polymers resulted in a significant reduction of viable cells in biofilm matrix despite the absence of thiol moieties. The effect was most pronounced for mature biofilms of S. aureus eradicated with NAC-Si-2.
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Affiliation(s)
- Maria Nowacka
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łssódź, Poland
| | - Anna Rygała
- Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Wólczańska 171/173, 90-924 Łssódź, Poland
| | - Dorota Kręgiel
- Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Wólczańska 171/173, 90-924 Łssódź, Poland
| | - Anna Kowalewska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łssódź, Poland.
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Landman C, Grill JP, Mallet JM, Marteau P, Humbert L, Le Balc’h E, Maubert MA, Perez K, Chaara W, Brot L, Beaugerie L, Sokol H, Thenet S, Rainteau D, Seksik P, Quévrain E. Inter-kingdom effect on epithelial cells of the N-Acyl homoserine lactone 3-oxo-C12:2, a major quorum-sensing molecule from gut microbiota. PLoS One 2018; 13:e0202587. [PMID: 30157234 PMCID: PMC6114859 DOI: 10.1371/journal.pone.0202587] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 08/06/2018] [Indexed: 02/06/2023] Open
Abstract
Background and aims N-acyl homoserine lactones (AHLs), which are autoinducer quorum-sensing molecules involved in the bacterial communication network, also interact with eukaryotic cells. Searching for these molecules in the context of inflammatory bowel disease (IBD) is appealing. The aims of our study were to look for AHL molecules in faecal samples from healthy subjects (HS) and IBD patients to correlate AHL profiles with the microbiome and investigate the effect of AHLs of interest on epithelial cells. Methods Using mass spectrometry, we characterised AHL profiles in faecal samples from HS (n = 26) and IBD patients in remission (n = 24) and in flare (n = 25) and correlated the presence of AHLs of interest with gut microbiota composition obtained by real-time qPCR and 16S sequencing. We synthesised AHLs of interest to test the inflammatory response after IL1β stimulation and paracellular permeability on Caco-2 cells. Results We observed 14 different AHLs, among which one was prominent. This AHL corresponded to 3-oxo-C12:2 and was found significantly less frequently in IBD patients in flare (16%) and in remission (37.5%) versus HS (65.4%) (p = 0.001). The presence of 3-oxo-C12:2 was associated with significantly higher counts of Firmicutes, especially Faecalbacterium prausnitzii, and lower counts of Escherichia coli. In vitro, 3-oxo-C12:2 exerted an anti-inflammatory effect on Caco-2 cells. Interestingly, although 3-oxo-C12, the well-known AHL from Pseudomonas aeruginosa, increased paracellular permeability, 3-oxo-C12:2 did not. Conclusions We identified AHLs in the human gut microbiota and discovered a new and prominent AHL, 3-oxo-C12:2, which correlates with normobiosis and exerts a protective effect on gut epithelial cells.
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Affiliation(s)
- Cécilia Landman
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Jean-Pierre Grill
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Jean-Maurice Mallet
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Philippe Marteau
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Lydie Humbert
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Eric Le Balc’h
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Marie-Anne Maubert
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Kevin Perez
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Wahiba Chaara
- Sorbonne Universités, INSERM, Immunology-Immunopathology-Immunotherapy (i3), Paris, France
| | - Loic Brot
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Laurent Beaugerie
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Harry Sokol
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Sophie Thenet
- Sorbonne Universités, Centre de Recherche des Cordeliers, PSL University, EPHE, Paris, France
| | - Dominique Rainteau
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
| | - Philippe Seksik
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
- * E-mail:
| | - Elodie Quévrain
- Sorbonne Université, École normale supérieure, PSL University, CNRS, INSERM, APHP, Hôpital Saint-Antoine, Laboratoire des biomolécules, LBM, Paris, France
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Extending the "One Strain Many Compounds" (OSMAC) Principle to Marine Microorganisms. Mar Drugs 2018; 16:md16070244. [PMID: 30041461 PMCID: PMC6070831 DOI: 10.3390/md16070244] [Citation(s) in RCA: 156] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 02/07/2023] Open
Abstract
Genomic data often highlights an inconsistency between the number of gene clusters identified using bioinformatic approaches as potentially producing secondary metabolites and the actual number of chemically characterized secondary metabolites produced by any given microorganism. Such gene clusters are generally considered as “silent”, meaning that they are not expressed under laboratory conditions. Triggering expression of these “silent” clusters could result in unlocking the chemical diversity they control, allowing the discovery of novel molecules of both medical and biotechnological interest. Therefore, both genetic and cultivation-based techniques have been developed aimed at stimulating expression of these “silent” genes. The principles behind the cultivation based approaches have been conceptualized in the “one strain many compounds” (OSMAC) framework, which underlines how a single strain can produce different molecules when grown under different environmental conditions. Parameters such as, nutrient content, temperature, and rate of aeration can be easily changed, altering the global physiology of a microbial strain and in turn significantly affecting its secondary metabolism. As a direct extension of such approaches, co-cultivation strategies and the addition of chemical elicitors have also been used as cues to activate “silent” clusters. In this review, we aim to provide a focused and comprehensive overview of these strategies as they pertain to marine microbes. Moreover, we underline how changes in some parameters which have provided important results in terrestrial microbes, but which have rarely been considered in marine microorganisms, may represent additional strategies to awaken “silent” gene clusters in marine microbes. Unfortunately, the empirical nature of the OSMAC approach forces scientists to perform extensive laboratory experiments. Nevertheless, we believe that some computation and experimental based techniques which are used in other disciplines, and which we discuss; could be effectively employed to help streamline the OSMAC based approaches. We believe that natural products discovery in marine microorganisms would be greatly aided through the integration of basic microbiological approaches, computational methods, and technological innovations, thereby helping unearth much of the as yet untapped potential of these microorganisms.
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Tools for engineering coordinated system behaviour in synthetic microbial consortia. Nat Commun 2018; 9:2677. [PMID: 29992956 PMCID: PMC6041260 DOI: 10.1038/s41467-018-05046-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 06/11/2018] [Indexed: 12/02/2022] Open
Abstract
Advancing synthetic biology to the multicellular level requires the development of multiple cell-to-cell communication channels that propagate information with minimal signal interference. The development of quorum-sensing devices, the cornerstone technology for building microbial communities with coordinated system behaviour, has largely focused on cognate acyl-homoserine lactone (AHL)/transcription factor pairs, while the use of non-cognate pairs as a design feature has received limited attention. Here, we demonstrate a large library of AHL-receiver devices, with all cognate and non-cognate chemical signal interactions quantified, and we develop a software tool that automatically selects orthogonal communication channels. We use this approach to identify up to four orthogonal channels in silico, and experimentally demonstrate the simultaneous use of three channels in co-culture. The development of multiple non-interfering cell-to-cell communication channels is an enabling step that facilitates the design of synthetic consortia for applications including distributed bio-computation, increased bioprocess efficiency, cell specialisation and spatial organisation. The engineering of synthetic microbial communities necessitates the use of synthetic, orthogonal cell-to-cell communication channels. Here the authors present a library of characterised AHL-receiver devices and a software tool for the automatic identification of non-interfering chemical communication channels.
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Zúñiga A, Fuente FDL, Federici F, Lionne C, Bônnet J, de Lorenzo V, González B. An Engineered Device for Indoleacetic Acid Production under Quorum Sensing Signals Enables Cupriavidus pinatubonensis JMP134 To Stimulate Plant Growth. ACS Synth Biol 2018; 7:1519-1527. [PMID: 29746094 DOI: 10.1021/acssynbio.8b00002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The environmental effects of chemical fertilizers and pesticides have encouraged the quest for new strategies to increase crop productivity with minimal impacts on the natural medium. Plant growth promoting rhizobacteria (PGPR) can contribute to this endeavor by improving fitness through better nutrition acquisition and stress tolerance. Using the neutral (non PGPR) rhizobacterium Cupriavidus pinatubonensis JMP134 as the host, we engineered a regulatory forward loop that triggered the synthesis of the phytohormone indole-3-acetic acid (IAA) in a manner dependent on quorum sensing (QS) signals. Implementation of the device in JMP134 yielded synthesis of IAA in an autoregulated manner, improving the growth of the roots of inoculated Arabidopsis thaliana. These results not only demonstrated the value of the designed genetic module, but also validated C. pinatubonensis JMP134 as a suitable vehicle for agricultural applications, as it is amenable to genetic manipulations.
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Affiliation(s)
- Ana Zúñiga
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez—Center of Applied Ecology and Sustainability, Santiago de Chile, 2640, Chile
- Centre de Biochimie Structurale, INSERM U1054, CNRS UMR5048, University of Montpellier, Montpellier, France
| | - Francisco de la Fuente
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez—Center of Applied Ecology and Sustainability, Santiago de Chile, 2640, Chile
- R2B Catalyst, Research Center, Andrés Bello 2299, Santiago, Chile
| | - Fernán Federici
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Fondo de Desarrollo de Áreas Prioritarias, Center for Genome Regulation, Millennium Institute for Integrative Systems and Synthetic Biology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Corinne Lionne
- Centre de Biochimie Structurale, INSERM U1054, CNRS UMR5048, University of Montpellier, Montpellier, France
| | - Jérome Bônnet
- Centre de Biochimie Structurale, INSERM U1054, CNRS UMR5048, University of Montpellier, Montpellier, France
| | | | - Bernardo González
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez—Center of Applied Ecology and Sustainability, Santiago de Chile, 2640, Chile
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Sekar J, Raju K, Duraisamy P, Ramalingam Vaiyapuri P. Potential of Finger Millet Indigenous Rhizobacterium Pseudomonas sp. MSSRFD41 in Blast Disease Management-Growth Promotion and Compatibility With the Resident Rhizomicrobiome. Front Microbiol 2018; 9:1029. [PMID: 29875748 PMCID: PMC5974220 DOI: 10.3389/fmicb.2018.01029] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/01/2018] [Indexed: 01/05/2023] Open
Abstract
Finger millet [Eleusine coracona (L). Gaertner] "Ragi" is a nutri-cereal with potential health benefits, and is utilized solely for human consumption in semi-arid regions of Asia and Africa. It is highly vulnerable to blast disease caused by Pyricularia grisea, resulting in 50-100% yield loss. Chemical fungicides are used for the management of blast disease, but with great safety concern. Alternatively, bioinoculants are widely used in promoting seedling efficiency, plant biomass, and disease control. Little is known about the impact of introduced indigenous beneficial rhizobacteria on the rhizosphere microbiota and growth promotion in finger millet. Strain MSSRFD41 exhibited a 22.35 mm zone of inhibition against P. grisea, produces antifungal metabolites, siderophores, hydrolytic enzymes, and IAA, and solubilizes phosphate. Environmental SEM analysis indicated the potential of MSSRFD41 to inhibit the growth of P. grisea by affecting cellular functions, which caused deformation in fungal hyphae. Bioprimed finger millet seeds exhibited significantly higher levels of germination, seedling vigor index, and enhanced shoot and root length compared to control seeds. Cross streaking and RAPD analysis showed that MSSRFD41 is compatible with different groups of rhizobacteria and survived in the rhizosphere. In addition, PLFA analysis revealed no significant difference in microbial biomass between the treated and control rhizosphere samples. Field trials showed that MSSRFD41 treatment significantly reduced blast infestation and enhanced plant growth compared to other treatments. A liquid formulated MSSRFD41 product maintained shelf life at an average of 108 CFU ml-1 over 150 days of storage at 25°C. Overall, results from this study demonstrated that Pseudomonas sp. MSSRFD41, an indigenous rhizobacterial strain, is an alternative, effective, and sustainable resource for the management of P. grisea infestation and growth promotion of finger millet.
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Affiliation(s)
- Jegan Sekar
- Microbiology Lab, M.S. Swaminathan Research Foundation, Chennai, India
| | - Kathiravan Raju
- Microbiology Lab, M.S. Swaminathan Research Foundation, Chennai, India
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Could Positive Feedback Enable Bacterial Pheromone Signaling To Coordinate Behaviors in Response to Heterogeneous Environmental Cues? mBio 2018; 9:mBio.00098-18. [PMID: 29764942 PMCID: PMC5954219 DOI: 10.1128/mbio.00098-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Pheromone signaling (PS) underlies many important bacterial behaviors, yet its ecological functions remain unresolved. Because pheromone-mediated behaviors require high cell density, the term "quorum sensing" is widely used to describe and make sense of PS. However, while this term has unified and popularized the field, bacterial PS clearly has roles beyond census taking, and the complexities of PS circuits indicate broader functional capacities. Two common features of bacterial PS are its regulation in response to environmental conditions and positive-feedback loops. Combined, these could enable PS to coordinate quorum-dependent group behaviors in response to heterogeneous environmental cues. Particularly in PS systems where positive feedback is strong, cells that are relatively far from a stimulatory environment could be recruited to a group response. Testing this model will benefit from in situ examination of relevant environmental cues and PS outputs in cells across populations, with and without positive feedback, in heterogeneous environments.
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42
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Zhao R, Zhang H, Zhang F, Yang F. Fast start-up anammox process using Acyl-homoserine lactones (AHLs) containing supernatant. J Environ Sci (China) 2018; 65:127-132. [PMID: 29548383 DOI: 10.1016/j.jes.2017.03.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 03/21/2017] [Accepted: 03/21/2017] [Indexed: 05/03/2023]
Abstract
N-dodecanoyl homoserine lactone (C12-HSL) was detected in the supernatant of an anammox granular sludge reactor (AGSR). C12-HSL could enhance the specific anammox activity of anammox biomass. Adding C12-HSL-containing AGSR supernatant into the continuously stirred tank reactors reduced the start-up time of the anammox process from 80 to 66days. Moreover, the nitrogen loading rate was also enhanced to 1.6 times that of the control reactor. AHLs could increase the secretion of extracellular polymeric substances and anammox obtained better enrichment with the addition of AHLs-containing AGSR supernatant. Denaturing gradient gel electrophoresis analysis further revealed that AHLs played a role in mediating microbial community parameters. In conclusion, adding AHL-containing supernatant could be an effective and economical way to accelerate the start-up of anammox.
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Affiliation(s)
- Ran Zhao
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China; School of Food and Environment, Dalian University of Technology, Panjin 124000, China.
| | - Hanmin Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Fan Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Fenglin Yang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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Li S, Chen S, Fan J, Cao Z, Ouyang W, Tong N, Hu X, Hu J, Li P, Feng Z, Huang X, Li Y, Xie M, He R, Jian J, Wu B, Xu C, Wu W, Guo J, Lin J, Sun P. Anti-biofilm effect of novel thiazole acid analogs against Pseudomonas aeruginosa through IQS pathways. Eur J Med Chem 2017; 145:64-73. [PMID: 29324344 DOI: 10.1016/j.ejmech.2017.12.076] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 12/20/2022]
Abstract
IQS has been proven to be a new quorum sensing (QS) system against bacterial biofilm formation, which is activated in the common phosphate-limiting environment of infected tissues taking over the central las system. Up to now, numerous biofilm inhibitors which function by affecting traditional QS system have been reported. However, no compound has been reported to exert anti-biofilm activity through IQS system. Herein, various novel IQS derivatives were synthesized by the reaction of thiazole-4-carboxylic acid with different linear alcohols (R-OH) or amines (R-NH2). IQS derivatives with four carbon chain length of R group were found to present the best biofilm inhibition activity. Compound B-11 as the model molecule was observed to inhibit biofilm formation only under phosphate-limiting condition, and increase in B-11 concentration significantly reduced the expression of rhlA-gfp and pqsA-gfp, but lasB-gfp. Moreover, B-11 reduced production of virulence factors of rhamnolipid and pyocyanin under phosphate limitation. These observations indicated that the synthesized compounds possessed the anti-biofilm activity through IQS pathways rather than traditional QS pathways, which pave a path for future molecular design against bacterial biofilm formation.
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Affiliation(s)
- Shengrong Li
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Siyu Chen
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Jilin Fan
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Zhen Cao
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Weihao Ouyang
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Ning Tong
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Xin Hu
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Jie Hu
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Peishan Li
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Zifeng Feng
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Xi Huang
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Yuying Li
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Mingshan Xie
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Ruikun He
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Jingyi Jian
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Biyuan Wu
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Chen Xu
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Weijian Wu
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Jialiang Guo
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Jing Lin
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China.
| | - Pinghua Sun
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China.
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Koonin EV. Viruses and mobile elements as drivers of evolutionary transitions. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0442. [PMID: 27431520 PMCID: PMC4958936 DOI: 10.1098/rstb.2015.0442] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/15/2016] [Indexed: 12/22/2022] Open
Abstract
The history of life is punctuated by evolutionary transitions which engender emergence of new levels of biological organization that involves selection acting at increasingly complex ensembles of biological entities. Major evolutionary transitions include the origin of prokaryotic and then eukaryotic cells, multicellular organisms and eusocial animals. All or nearly all cellular life forms are hosts to diverse selfish genetic elements with various levels of autonomy including plasmids, transposons and viruses. I present evidence that, at least up to and including the origin of multicellularity, evolutionary transitions are driven by the coevolution of hosts with these genetic parasites along with sharing of ‘public goods’. Selfish elements drive evolutionary transitions at two distinct levels. First, mathematical modelling of evolutionary processes, such as evolution of primitive replicator populations or unicellular organisms, indicates that only increasing organizational complexity, e.g. emergence of multicellular aggregates, can prevent the collapse of the host–parasite system under the pressure of parasites. Second, comparative genomic analysis reveals numerous cases of recruitment of genes with essential functions in cellular life forms, including those that enable evolutionary transitions. This article is part of the themed issue ‘The major synthetic evolutionary transitions’.
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Affiliation(s)
- Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
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Whiteley M, Diggle SP, Greenberg EP. Progress in and promise of bacterial quorum sensing research. Nature 2017; 551:313-320. [PMID: 29144467 PMCID: PMC5870893 DOI: 10.1038/nature24624] [Citation(s) in RCA: 649] [Impact Index Per Article: 92.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 10/09/2017] [Indexed: 12/13/2022]
Abstract
This Review highlights how we can build upon the relatively new and rapidly developing field of research into bacterial quorum sensing (QS). We now have a depth of knowledge about how bacteria use QS signals to communicate with each other and to coordinate their activities. In recent years there have been extraordinary advances in our understanding of the genetics, genomics, biochemistry, and signal diversity of QS. We are beginning to understand the connections between QS and bacterial sociality. This foundation places us at the beginning of a new era in which researchers will be able to work towards new medicines to treat devastating infectious diseases, and use bacteria to understand the biology of sociality.
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Affiliation(s)
- Marvin Whiteley
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, John Ring LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX USA
| | - Stephen P. Diggle
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA USA
| | - E. Peter Greenberg
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA USA, Guangdong Innovative and Entrepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology, South China Agricultural University, Guangzhou, China
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Quorum sensing integrates environmental cues, cell density and cell history to control bacterial competence. Nat Commun 2017; 8:854. [PMID: 29021534 PMCID: PMC5636887 DOI: 10.1038/s41467-017-00903-y] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 08/03/2017] [Indexed: 01/08/2023] Open
Abstract
Streptococcus pneumoniae becomes competent for genetic transformation when exposed to an autoinducer peptide known as competence-stimulating peptide (CSP). This peptide was originally described as a quorum-sensing signal, enabling individual cells to regulate competence in response to population density. However, recent studies suggest that CSP may instead serve as a probe for sensing environmental cues, such as antibiotic stress or environmental diffusion. Here, we show that competence induction can be simultaneously influenced by cell density, external pH, antibiotic-induced stress, and cell history. Our experimental data is explained by a mathematical model where the environment and cell history modify the rate at which cells produce or sense CSP. Taken together, model and experiments indicate that autoinducer concentration can function as an indicator of cell density across environmental conditions, while also incorporating information on environmental factors or cell history, allowing cells to integrate cues such as antibiotic stress into their quorum-sensing response. This unifying perspective may apply to other debated quorum-sensing systems. Peptide CSP regulates natural competence in pneumococci and has been proposed as a quorum-sensing signal or a probe for sensing environmental cues. Here, the authors show that CSP levels can indeed act as an indicator of cell density and also incorporate information on environmental factors or cell history.
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Intercellular Communication via the comX-Inducing Peptide (XIP) of Streptococcus mutans. J Bacteriol 2017; 199:JB.00404-17. [PMID: 28808131 DOI: 10.1128/jb.00404-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 08/08/2017] [Indexed: 12/29/2022] Open
Abstract
Gram-positive bacteria utilize exported peptides to coordinate genetic and physiological processes required for biofilm formation, stress responses, and ecological competitiveness. One example is activation of natural genetic competence by ComR and the com X -inducing peptide (XIP) in Streptococcus mutans Although the competence pathway can be activated by the addition of synthetic XIP in defined medium, the hypothesis that XIP is able to function as an intercellular signaling molecule has not been rigorously tested. Coculture model systems were developed that included a "sender" strain that overexpressed the XIP precursor (ComS) and a "responder" strain harboring a green fluorescent protein (GFP) reporter fused to a ComR-activated gene (comX) promoter. The ability of the sender strain to provide a signal to activate GFP expression was monitored at the individual cell and population levels using (i) planktonic culture systems, (ii) cells suspended in an agarose matrix, or (iii) cells growing in biofilms. XIP was shown to be freely diffusible, and XIP signaling between the S. mutans sender and responder strains did not require cell-to-cell contact. The presence of a sucrose-derived exopolysaccharide matrix diminished the efficiency of XIP signaling in biofilms, possibly by affecting the spatial distribution of XIP senders and potential responders. Intercellular signaling was greatly impaired in a strain lacking the primary autolysin, AtlA, and was substantially greater when the sender strain underwent lysis. Collectively, these data provide evidence that S. mutans XIP can indeed function as a peptide signal between cells and highlight the importance of studying signaling with an endogenously produced peptide(s) in populations in various environments and physiologic states.IMPORTANCE The comX-inducing peptide (XIP) of Streptococcus mutans is a key regulatory element in the activation of genetic competence, which allows cells to take up extracellular DNA. XIP has been found in cell culture fluids, and the addition of synthetic XIP to physiologically receptive cells can robustly induce competence gene expression. However, there is a lack of consensus as to whether XIP can function as an intercellular communication signal. Here, we show that XIP indeed signals between cells in S. mutans, but that cell lysis may be a critical factor, as opposed to a dedicated secretion/processing system, in allowing for release of XIP into the environment. The results have important implications in the context of the ecology, virulence, and evolution of a ubiquitous human pathogen and related organisms.
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Mariana SS, Mariangela H, Marco AN. Production of polyhydroxybutyrate (PHB) and biofilm by Azospirillum brasilense aiming at the development of liquid inoculants with high performance. ACTA ACUST UNITED AC 2017. [DOI: 10.5897/ajb2017.16162] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Fukami J, Abrantes JLF, del Cerro P, Nogueira MA, Ollero FJ, Megías M, Hungria M. Revealing strategies of quorum sensing in Azospirillum brasilense strains Ab-V5 and Ab-V6. Arch Microbiol 2017; 200:47-56. [DOI: 10.1007/s00203-017-1422-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 07/21/2017] [Accepted: 07/30/2017] [Indexed: 11/24/2022]
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Romano G, Costantini M, Sansone C, Lauritano C, Ruocco N, Ianora A. Marine microorganisms as a promising and sustainable source of bioactive molecules. MARINE ENVIRONMENTAL RESEARCH 2017; 128:58-69. [PMID: 27160988 DOI: 10.1016/j.marenvres.2016.05.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/29/2016] [Accepted: 05/01/2016] [Indexed: 06/05/2023]
Abstract
There is an urgent need to discover new drug entities due to the increased incidence of severe diseases as cancer and neurodegenerative pathologies, and reducing efficacy of existing antibiotics. Recently, there is a renewed interest in exploring the marine habitat for new pharmaceuticals also thanks to the advancement in cultivation technologies and in molecular biology techniques. Microorganisms represent a still poorly explored resource for drug discovery. The possibility of obtaining a continuous source of bioactives from marine microorganisms, more amenable to culturing compared to macro-organisms, may be able to meet the challenging demands of pharmaceutical industries. This would enable a more environmentally-friendly approach to drug discovery and overcome the over-utilization of marine resources and the use of destructive collection practices. The importance of the topic is underlined by the number of EU projects funded aimed at improving the exploitation of marine organisms for drug discovery.
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Affiliation(s)
- G Romano
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy.
| | - M Costantini
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - C Sansone
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - C Lauritano
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - N Ruocco
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy; Department of Biology, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, Via Cinthia, 80126 Napoli, Italy; Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry-CNR, Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
| | - A Ianora
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
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