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Gonzales M, Jacquet P, Gaucher F, Chabrière É, Plener L, Daudé D. AHL-Based Quorum Sensing Regulates the Biosynthesis of a Variety of Bioactive Molecules in Bacteria. JOURNAL OF NATURAL PRODUCTS 2024; 87:1268-1284. [PMID: 38390739 DOI: 10.1021/acs.jnatprod.3c00672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Bacteria are social microorganisms that use communication systems known as quorum sensing (QS) to regulate diverse cellular behaviors including the production of various secreted molecules. Bacterial secondary metabolites are widely studied for their bioactivities including antibiotic, antifungal, antiparasitic, and cytotoxic compounds. Besides playing a crucial role in natural bacterial niches and intermicrobial competition by targeting neighboring organisms and conferring survival advantages to the producer, these bioactive molecules may be of prime interest to develop new antimicrobials or anticancer therapies. This review focuses on bioactive compounds produced under acyl homoserine lactone-based QS regulation by Gram-negative bacteria that are pathogenic to humans and animals, including the Burkholderia, Serratia, Pseudomonas, Chromobacterium, and Pseudoalteromonas genera. The synthesis, regulation, chemical nature, biocidal effects, and potential applications of these identified toxic molecules are presented and discussed in light of their role in microbial interactions.
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Affiliation(s)
- Mélanie Gonzales
- Aix Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille 13288, France
- Gene&GreenTK, Marseille 13005, France
| | | | | | - Éric Chabrière
- Aix Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille 13288, France
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Yang Y, Zhang W, Liu W, He D, Wan W. Irreversible community difference between bacterioplankton generalists and specialists in response to lake dredging. WATER RESEARCH 2023; 243:120344. [PMID: 37482008 DOI: 10.1016/j.watres.2023.120344] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/25/2023]
Abstract
Understanding response of bacterioplankton community responsible for maintaining ecological functions of aquatic ecosystems to environmental disturbance is an important subject. However, it remains largely unclear how bacterioplankton generalists and specialists respond to dredging disturbance. Illumina MiSeq sequencing and statistical analyses were used to evaluate landscape patterns, evolutionary potentials, environmental adaptability, and community assembly processes of generalists and specialists in response to dredging in eutrophic Lake Nanhu. The Proteobacteria and Actinobacteria dominated bacterioplankton communities of generalists and specialists, and abundances of Proteobacteria decreased and Actinobacteria increased after dredging. The generalists displayed higher phylogenetic distance, richness difference, speciation rate, extinction rate, and diversification rate as well as stronger environmental adaptation than that of specialists. In contrast, the specialists rather than generalists showed higher community diversity, taxonomic distance, and species replacement as well as closer phylogenetic clustering. Stochastic processes dominated community assemblies of generalists and specialists, and stochasticity exhibited a larger effect on community assembly of generalists rather than specialists. Our results emphasized that lake dredging could change landscape patterns of bacterioplankton generalists and specialists, whereas the short-term dredging conducted within one year was unable to reverse community difference between generalists and specialists. Our findings extend our understanding of how bacterioplankton generalists and specialists responding to dredging disturbance, and these findings might in turn call on long-term dredging for better ecological restoration of eutrophic lakes.
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Affiliation(s)
- Yuyi Yang
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430070, China; Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station, Chinese Academy of Sciences & Hubei Province, Wuhan 430070, China
| | - Weihong Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430070, China; Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station, Chinese Academy of Sciences & Hubei Province, Wuhan 430070, China
| | - Wenzhi Liu
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430070, China; Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station, Chinese Academy of Sciences & Hubei Province, Wuhan 430070, China
| | - Donglan He
- College of Life Science, South-Central Minzu University, Wuhan 430070, China
| | - Wenjie Wan
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430070, China; Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station, Chinese Academy of Sciences & Hubei Province, Wuhan 430070, China.
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Adaikpoh BI, Romanowski SB, Eustáquio AS. Understanding Autologous Spliceostatin Transcriptional Regulation to Derive Parts for Heterologous Expression in a Burkholderia Bacterial Host. ACS Synth Biol 2023; 12:1952-1960. [PMID: 37338297 PMCID: PMC10527236 DOI: 10.1021/acssynbio.3c00228] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
Burkholderia β-Proteobacteria are emerging sources of natural products. We are interested in developing Burkholderia sp. FERM BP-3421 into a synthetic biology chassis to facilitate natural product discovery. FERM BP-3421 produces autologous spliceostatins on gram per liter scale. We reasoned that transcription factors and promoters that regulate spliceostatin biosynthesis would provide valuable parts for heterologous expression. Herein we demonstrate that fr9A encodes a pathway-specific transcriptional activator of spliceostatin biosynthesis. In-frame deletion of fr9A abolished spliceostatin production, which was restored by genetic complementation. Using transcriptomics and green fluorescent protein (GFP) reporter assays, we identified four fr9 promoters, three of which are activated by LuxR-type regulator Fr9A. We then constructed an Fr9A-regulated promoter system that was compared to benchmarks and effectively applied for GFP and capistruin lasso peptide expression in an optimized host background. Our findings enrich the genetic toolbox for optimizing heterologous expression and promoting the discovery and development of natural products from Burkholderia bacteria.
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Affiliation(s)
- Barbara I. Adaikpoh
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, 60607, United States
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Sean B. Romanowski
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, 60607, United States
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Alessandra S. Eustáquio
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, 60607, United States
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60607, United States
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Dai C, Qu Y, Wu W, Li S, Chen Z, Lian S, Jing J. QSP: An open sequence database for quorum sensing related gene analysis with an automatic annotation pipeline. WATER RESEARCH 2023; 235:119814. [PMID: 36934538 DOI: 10.1016/j.watres.2023.119814] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 02/18/2023] [Accepted: 02/24/2023] [Indexed: 06/18/2023]
Abstract
Quorum sensing (QS) has attracted great attention due to its important role in the bacterial interactions and its relevance to water management. With the development of high-throughput sequencing technology, a specific database for QS-related sequence annotation is urgently needed. Here, Hidden Markov Model (HMM) profiles for 38 types of QS-related proteins were built using a total of 4024 collected seed sequences. Based on both homolog search and keywords confirmation against the non-redundant database, we established a QS-related protein (QSP) database, that includes 809,721 protein sequences and 186,133 nucleotide sequences, downloaded available at: https://github.com/chunxiao-dcx/QSP. The entries were classified into 38 types and 315 subtypes among 91 bacterial phyla. Furthermore, an automatic annotation pipeline, named QSAP, was developed for rapid annotation, classification and abundance quantification of QSP-like sequences from sequencing data. This pipeline provided the two homolog alignment strategies offered by Diamond (Blastp) or HMMER (Hmmscan), as well as a data cleansing function for a subset or union set of the hits. The pipeline was tested using 14 metagenomic samples from various water environments, including activated sludge, deep-sea sediments, estuary water, and reservoir water. The QSAP pipeline is freely available for academic use in the code repository at: https://github.com/chunxiao-dcx/QSAP. The establishment of this database and pipeline, provides a useful tool for QS-related sequence annotation in a wide range of projects, and will increase our understanding of QS communication in aquatic environments.
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Affiliation(s)
- Chunxiao Dai
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yuanyuan Qu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Weize Wu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Shuzhen Li
- Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Zhuo Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Shengyang Lian
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jiawei Jing
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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Xu Z, Tian P. Rethinking Biosynthesis of Aclacinomycin A. Molecules 2023; 28:molecules28062761. [PMID: 36985733 PMCID: PMC10054333 DOI: 10.3390/molecules28062761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 03/22/2023] Open
Abstract
Aclacinomycin A (ACM-A) is an anthracycline antitumor agent widely used in clinical practice. The current industrial production of ACM-A relies primarily on chemical synthesis and microbial fermentation. However, chemical synthesis involves multiple reactions which give rise to high production costs and environmental pollution. Microbial fermentation is a sustainable strategy, yet the current fermentation yield is too low to satisfy market demand. Hence, strain improvement is highly desirable, and tremendous endeavors have been made to decipher biosynthesis pathways and modify key enzymes. In this review, we comprehensively describe the reported biosynthesis pathways, key enzymes, and, especially, catalytic mechanisms. In addition, we come up with strategies to uncover unknown enzymes and improve the activities of rate-limiting enzymes. Overall, this review aims to provide valuable insights for complete biosynthesis of ACM-A.
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Núñez-Montero K, Rojas-Villalta D, Barrientos L. Antarctic Sphingomonas sp. So64.6b showed evolutive divergence within its genus, including new biosynthetic gene clusters. Front Microbiol 2022; 13:1007225. [DOI: 10.3389/fmicb.2022.1007225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 10/26/2022] [Indexed: 11/21/2022] Open
Abstract
IntroductionThe antibiotic crisis is a major human health problem. Bioprospecting screenings suggest that proteobacteria and other extremophile microorganisms have biosynthetic potential for the production novel antimicrobial compounds. An Antarctic Sphingomonas strain (So64.6b) previously showed interesting antibiotic activity and elicitation response, then a relationship between environmental adaptations and its biosynthetic potential was hypothesized. We aimed to determine the genomic characteristics in So64.6b strain related to evolutive traits for the adaptation to the Antarctic environment that could lead to its diversity of potentially novel antibiotic metabolites.MethodsThe complete genome sequence of the Antarctic strain was obtained and mined for Biosynthetic Gene Clusters (BGCs) and other unique genes related to adaptation to extreme environments. Comparative genome analysis based on multi-locus phylogenomics, BGC phylogeny, and pangenomics were conducted within the closest genus, aiming to determine the taxonomic affiliation and differential characteristics of the Antarctic strain.Results and discussionThe Antarctic strain So64.6b showed a closest identity with Sphingomonas alpina, however containing a significant genomic difference of ortholog cluster related to degradation multiple pollutants. Strain So64.6b had a total of six BGC, which were predicted with low to no similarity with other reported clusters; three were associated with potential novel antibiotic compounds using ARTS tool. Phylogenetic and synteny analysis of a common BGC showed great diversity between Sphingomonas genus but grouping in clades according to similar isolation environments, suggesting an evolution of BGCs that could be linked to the specific ecosystems. Comparative genomic analysis also showed that Sphingomonas species isolated from extreme environments had the greatest number of predicted BGCs and a higher percentage of genetic content devoted to BGCs than the isolates from mesophilic environments. In addition, some extreme-exclusive clusters were found related to oxidative and thermal stress adaptations, while pangenome analysis showed unique resistance genes on the Antarctic strain included in genetic islands. Altogether, our results showed the unique genetic content on Antarctic strain Sphingomonas sp. So64.6, −a probable new species of this genetically divergent genus–, which could have potentially novel antibiotic compounds acquired to cope with Antarctic poly-extreme conditions.
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Robes JMD, Altamia MA, Murdock EG, Concepcion GP, Haygood MG, Puri AW. A Conserved Biosynthetic Gene Cluster Is Regulated by Quorum Sensing in a Shipworm Symbiont. Appl Environ Microbiol 2022; 88:e0027022. [PMID: 35611654 PMCID: PMC9195952 DOI: 10.1128/aem.00270-22] [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: 02/10/2022] [Accepted: 05/01/2022] [Indexed: 11/20/2022] Open
Abstract
Bacterial symbionts often provide critical functions for their hosts. For example, wood-boring bivalves called shipworms rely on cellulolytic endosymbionts for wood digestion. However, how the relationship between shipworms and their bacterial symbionts is formed and maintained remains unknown. Quorum sensing (QS) often plays an important role in regulating symbiotic relationships. We identified and characterized a QS system found in Teredinibacter sp. strain 2052S, a gill isolate of the wood-boring shipworm Bactronophorus cf. thoracites. We determined that 2052S produces the signal N-decanoyl-l-homoserine lactone (C10-HSL) and that this signal controls the activation of a biosynthetic gene cluster colocated in the symbiont genome that is conserved among all symbiotic Teredinibacter isolates. We subsequently identified extracellular metabolites associated with the QS regulon, including ones linked to the conserved biosynthetic gene cluster, using mass spectrometry-based molecular networking. Our results demonstrate that QS plays an important role in regulating secondary metabolism in this shipworm symbiont. This information provides a step toward deciphering the molecular details of the relationship between these symbionts and their hosts. Furthermore, because shipworm symbionts harbor vast yet underexplored biosynthetic potential, understanding how their secondary metabolism is regulated may aid future drug discovery efforts using these organisms. IMPORTANCE Bacteria play important roles as symbionts in animals ranging from invertebrates to humans. Despite this recognized importance, much is still unknown about the molecular details of how these relationships are formed and maintained. One of the proposed roles of shipworm symbionts is the production of bioactive secondary metabolites due to the immense biosynthetic potential found in shipworm symbiont genomes. Here, we report that a shipworm symbiont uses quorum sensing to coordinate activation of its extracellular secondary metabolism, including the transcriptional activation of a biosynthetic gene cluster that is conserved among many shipworm symbionts. This work is a first step toward linking quorum sensing, secondary metabolism, and symbiosis in wood-boring shipworms.
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Affiliation(s)
- Jose Miguel D. Robes
- Department of Chemistry, University of Utah, Salt Lake City, Utah, USA
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, Utah, USA
- The Marine Science Institute, University of the Philippines Diliman, Quezon City, Philippines
| | - Marvin A. Altamia
- The Marine Science Institute, University of the Philippines Diliman, Quezon City, Philippines
| | - Ethan G. Murdock
- Department of Chemistry, University of Utah, Salt Lake City, Utah, USA
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, Utah, USA
| | - Gisela P. Concepcion
- The Marine Science Institute, University of the Philippines Diliman, Quezon City, Philippines
| | - Margo G. Haygood
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah, USA
| | - Aaron W. Puri
- Department of Chemistry, University of Utah, Salt Lake City, Utah, USA
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, Utah, USA
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Assembly of 97 Novel Bacterial Genomes in the Microbial Community Affiliated with Polyvinyl Alcohol in Soil of Northern China. BIOMED RESEARCH INTERNATIONAL 2022; 2022:2229147. [PMID: 35087906 PMCID: PMC8789413 DOI: 10.1155/2022/2229147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 10/05/2021] [Accepted: 10/07/2021] [Indexed: 11/25/2022]
Abstract
Background Undeveloped ecosystems belong to rich source of microbial population, of which resources remain unearthed. A kind of polymeric compound system with high polyvinyl alcohol (PVA) content has been reported and named Taisui. Marker gene amplification showed that Taisui harbored little-explored microbial communities. Aim To address this issue, our study attempted to recover draft genomes and functional potential from microbial communities in Taisui using the metagenomic approach. Material and Methods. Taisui communities provided 97 novel bacterial genomes from 13 bacterial phyla, including bacteria candidate phylum. Two novel genus-level lineages were recovered from Planctomycetes and Chloroflexi. Based on the draft genomes, we expanded the number of taxa with potential productions of PKS and NRPS in phyla including Candidatus Dadabacteria, Chloroflexi, and Planctomycetes. Results A rich diversity of PVA dehydrogenase genes from 4 phyla, involving Proteobacteria, Acidobacteria, Acitinobacteria, and Planctomycetes, were identified. The phylogenetic tree of PVA dehydrogenase showed the possibility of horizontal gene transfer between microbes. Conclusion Our study underscores the substantial microbial diversity and PVA degradation potential in the previously unexplored Taisui system.
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Ruiz P, Sepulveda D, Vidal JM, Romero R, Contreras D, Barros J, Carrasco C, Ruiz-Tagle N, Romero A, Urrutia H, Oliver C. Piscirickettsia salmonis Produces a N-Acetyl-L-Homoserine Lactone as a Bacterial Quorum Sensing System-Related Molecule. Front Cell Infect Microbiol 2021; 11:755496. [PMID: 34760722 PMCID: PMC8573184 DOI: 10.3389/fcimb.2021.755496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 10/11/2021] [Indexed: 12/21/2022] Open
Abstract
Piscirickettsia salmonis is the etiological agent of piscirickettsiosis, the most prevalent disease in salmonid species in Chilean salmonids farms. Many bacteria produce N-acyl-homoserine lactones (AHLs) as a quorum-sensing signal molecule to regulate gene expression in a cell density-dependent manner, and thus modulate physiological characteristics and several bacterial mechanisms. In this study, a fluorescent biosensor system method and gas chromatography-tandem mass spectrometry (GC/MS) were combined to detect AHLs produced by P. salmonis. These analyses revealed an emitted fluorescence signal when the biosensor P. putida EL106 (RPL4cep) was co-cultured with both, P. salmonis LF-89 type strain and an EM-90-like strain Ps007, respectively. Furthermore, the production of an AHL-type molecule was confirmed by GC/MS by both P. salmonis strains, which identified the presence of a N-acetyl-L-homoserine Lactone in the supernatant extract. However, It is suggested that an alternate pathway could synthesizes AHLs, which should be address in future experiments in order to elucidate this important bacterial process. To the best of our knowledge, the present report is the first to describe the type of AHLs produced by P. salmonis.
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Affiliation(s)
- Pamela Ruiz
- Laboratorio de Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile.,Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Talcahuano, Chile
| | - Daniela Sepulveda
- Laboratorio de Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile
| | - José Miguel Vidal
- Laboratorio de Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile.,Departamento de Investigación y Desarrollo, Ecombio limitada, Concepción, Chile
| | - Romina Romero
- Laboratorio de Investigaciones Medioambientales de Zonas Áridas (LIMZA), Depto. Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Tarapacá, Arica, Chile
| | - David Contreras
- Departamento de Química Analítica e Inorgánica, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Javier Barros
- Departamento de Investigación y Desarrollo, Micbiotech Spa, Concepción, Chile
| | - Carlos Carrasco
- Laboratorio de Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile
| | - Nathaly Ruiz-Tagle
- Laboratorio de Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile
| | - Alex Romero
- Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Facultad de Ciencias Veterinarias, Instituto de Patología Animal, Valdivia, Chile.,Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile
| | - Homero Urrutia
- Laboratorio de Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile.,Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Cristian Oliver
- Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Facultad de Ciencias Veterinarias, Instituto de Patología Animal, Valdivia, Chile
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Wengert PC, Wong NH, Barton HA, Gan HM, Hudson AO, Savka MA. Genomic characterization of bacteria from the ultra-oligotrophic Madison aquifer: insight into the archetypical LuxI/LuxR and identification of novel LuxR solos. BMC Res Notes 2021; 14:175. [PMID: 33964980 PMCID: PMC8105983 DOI: 10.1186/s13104-021-05589-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 04/28/2021] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES To characterize the bacterial community of Wind Cave's Madison aquifer through whole-genome sequencing, and to better understand the bacterial ecology by identifying genes involved in acyl-homoserine lactone (AHL) based quorum-sensing (QS) systems. RESULTS Genome-based taxonomic classification revealed the microbial richness present in the pristine Madison aquifer. The strains were found to span eleven genera and fourteen species, of which eight had uncertain taxonomic classifications. The genomes of strains SD129 and SD340 were found to contain the archetypical AHL QS system composed of two genes, luxI and luxR. Surprisingly, the genomes of strains SD115, SD129, SD274 and SD316 were found to contain one to three luxR orphans (solos). Strain SD129, besides possessing an archetypical AHL QS luxI-luxR pair, also contained two luxR solos, while strain SD316 contained three LuxR solos and no luxI-luxR pairs. The ligand-binding domain of two LuxR solos, one each from strains SD129 and SD316, were found to contain novel substitutions not previously reported, thus may represent two LuxR orphans that detection and response to unknown self-produced signal(s), or to signal(s) produced by other organisms.
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Affiliation(s)
- Peter C Wengert
- Thomas H. Gosnell School of Life Sciences, College of Science, Rochester Institute of Technology, Rochester, NY, 14623, USA
| | - Narayan H Wong
- Thomas H. Gosnell School of Life Sciences, College of Science, Rochester Institute of Technology, Rochester, NY, 14623, USA
| | - Hazel A Barton
- Department of Biology, University of Akron, Akron, OH, USA
| | - Han Ming Gan
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Vic, 3220, Australia.,GeneSEQ Sdn Bhd, Bandar Bukit Beruntung, 48300, Rawang, Selangor, Malaysia
| | - André O Hudson
- Thomas H. Gosnell School of Life Sciences, College of Science, Rochester Institute of Technology, Rochester, NY, 14623, USA
| | - Michael A Savka
- Thomas H. Gosnell School of Life Sciences, College of Science, Rochester Institute of Technology, Rochester, NY, 14623, USA.
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Identification of a solo acylhomoserine lactone synthase from the myxobacterium Archangium gephyra. Sci Rep 2021; 11:3018. [PMID: 33542315 PMCID: PMC7862692 DOI: 10.1038/s41598-021-82480-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/20/2021] [Indexed: 12/31/2022] Open
Abstract
Considered a key taxon in soil and marine microbial communities, myxobacteria exist as coordinated swarms that utilize a combination of lytic enzymes and specialized metabolites to facilitate predation of microbes. This capacity to produce specialized metabolites and the associated abundance of biosynthetic pathways contained within their genomes have motivated continued drug discovery efforts from myxobacteria. Of all myxobacterial biosynthetic gene clusters deposited in the antiSMASH database, only one putative acylhomoserine lactone (AHL) synthase, agpI, was observed, in genome data from Archangium gephyra. Without an AHL receptor also apparent in the genome of A. gephyra, we sought to determine if AgpI was an uncommon example of an orphaned AHL synthase. Herein we report the bioinformatic assessment of AgpI and discovery of a second AHL synthase from Vitiosangium sp. During axenic cultivation conditions, no detectible AHL metabolites were observed in A. gephyra extracts. However, heterologous expression of each synthase in Escherichia coli provided detectible quantities of 3 AHL signals including 2 known AHLs, C8-AHL and C9-AHL. These results suggest that A. gephyra AHL production is dormant during axenic cultivation. The functional, orphaned AHL synthase, AgpI, is unique to A. gephyra, and its utility to the predatory myxobacterium remains unknown.
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Zakaria BS, Dhar BR. Changes in syntrophic microbial communities, EPS matrix, and gene-expression patterns in biofilm anode in response to silver nanoparticles exposure. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 734:139395. [PMID: 32454336 DOI: 10.1016/j.scitotenv.2020.139395] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/10/2020] [Accepted: 05/10/2020] [Indexed: 05/25/2023]
Abstract
Understanding the toxic effect of silver nanoparticles (AgNPs) on various biological wastewater treatment systems is of significant interest to researchers. In recent years, microbial electrochemical technologies have opened up new opportunities for bioenergy and chemicals production from organic wastewater. However, the effects of AgNPs on microbial electrochemical systems are yet to be understood fully. Notably, no studies have investigated the impact of AgNPs on a microbial electrochemical system fed with a complex fermentable substrate. Here, we investigated the impact of AgNPs (50 mg/L) exposure to a biofilm anode in a microbial electrolysis cell (MEC) fed with glucose. The volumetric current density was 29 ± 2.0 A/m3 before the AgNPs exposure, which decreased to 20 ± 2.2 A/m3 after AgNPs exposure. The biofilms produced more extracellular polymeric substances (EPS) to cope with the AgNPs exposure, while carbohydrate to protein ratio in EPS considerably increased from 0.4 to 0.7. Scanning electron microscope (SEM) imaging also confirmed the marked excretion of EPS, forming a thick layer covering the anode biofilms after AgNPs injection. Transmission electron microscope (TEM) imaging showed that AgNPs still penetrated some microbial cells, which could explain the deterioration of MEC performance after AgNPs exposure. The relative expression level of the quorum signalling gene (LuxR) increased by 30%. Microbial community analyses suggested that various fermentative bacterial species (e.g., Bacteroides, Synergistaceae_vadinCA02, Dysgonomonas, etc.) were susceptible to AgNPs toxicity, which led to the disruption of their syntrophic partnership with electroactive bacteria. The abundance of some specific electroactive bacteria (e.g., Geobacter species) also decreased. Moreover, decreased relative expressions of various extracellular electron transfer associated genes (omcB, omcC, omcE, omcZ, omcS, and pilA) were observed. However, the members of family Enterobacteriaceae, known to perform a dual function of fermentation and anodic respiration, became dominant after biofilm anode exposed to AgNPs. Thus, EPS extraction provided partial protection against AgNPs exposure.
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Affiliation(s)
- Basem S Zakaria
- Civil and Environmental Engineering, University of Alberta, 9211-116 Street NW, Edmonton, AB T6G 1H9, Canada
| | - Bipro Ranjan Dhar
- Civil and Environmental Engineering, University of Alberta, 9211-116 Street NW, Edmonton, AB T6G 1H9, Canada.
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Mukherji R, Zhang S, Chowdhury S, Stallforth P. Chimeric LuxR Transcription Factors Rewire Natural Product Regulation. Angew Chem Int Ed Engl 2020; 59:6192-6195. [PMID: 31943579 PMCID: PMC7187462 DOI: 10.1002/anie.201914449] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/12/2019] [Indexed: 01/17/2023]
Abstract
LuxR-type transcriptional activator proteins frequently regulate the expression of biosynthetic gene clusters (BGCs). With only a fraction of bacterial BGCs being expressed under standard culturing conditions, modulation of LuxRs would provide a powerful approach to activate silent clusters. We show that by exploiting the modular nature of LuxR proteins, it is possible to construct functional chimeric LuxRs, which enables both the rewiring of quorum sensing systems and the activation of silent BGCs. Importantly, our strategy allowed us to identify the novel natural product pseudomonol from a bacterium of the genus Pseudomonas.
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Affiliation(s)
- Ruchira Mukherji
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Shuaibing Zhang
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Somak Chowdhury
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Pierre Stallforth
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI)Beutenbergstrasse 11a07745JenaGermany
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14
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Mukherji R, Zhang S, Chowdhury S, Stallforth P. Chimeric LuxR Transcription Factors Rewire Natural Product Regulation. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Ruchira Mukherji
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Shuaibing Zhang
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Somak Chowdhury
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Pierre Stallforth
- Independent Junior Research Group Chemistry of Microbial CommunicationLeibniz Institute for Natural Product Research and Infection BiologyHans Knöll Institute (HKI) Beutenbergstrasse 11a 07745 Jena Germany
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15
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Greenberg EP, Chandler JR, Seyedsayamdost MR. The Chemistry and Biology of Bactobolin: A 10-Year Collaboration with Natural Product Chemist Extraordinaire Jon Clardy. JOURNAL OF NATURAL PRODUCTS 2020; 83:738-743. [PMID: 32105069 PMCID: PMC8118907 DOI: 10.1021/acs.jnatprod.9b01237] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Bactobolin is a hybrid natural product with potent cytotoxic activity. Its production from Burkholderia thailandensis was reported as part of a collaboration between the Greenberg and Clardy laboratories in 2010. The collaboration sparked a series of studies leading to the discovery of new analogues and associated structure-activity relationships, the identification of the bactobolin biosynthetic gene cluster and assembly of its unusual amino acid building block, the molecular target of and resistance to the antibiotic, and finally an X-ray crystal structure of the ribosome-bactobolin complex. Herein, we review the collaborations that led to our current understanding of the chemistry and biology of bactobolin.
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Affiliation(s)
- E Peter Greenberg
- Department of Microbiology, School of Medicine, University of Washington, Seattle, Washington 98195, United States
| | - Josephine R Chandler
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045, United States
| | - Mohammad R Seyedsayamdost
- Departments of Chemistry and Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
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16
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Feng L, Schaefer AL, Hu M, Chen R, Greenberg EP, Zhou J. Virulence Factor Identification in the Banana Pathogen Dickeya zeae MS2. Appl Environ Microbiol 2019; 85:e01611-19. [PMID: 31540986 PMCID: PMC6856320 DOI: 10.1128/aem.01611-19] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 09/16/2019] [Indexed: 11/20/2022] Open
Abstract
The phytopathogen Dickeya zeae MS2 is a particularly virulent agent of banana soft rot disease. To begin to understand this banana disease and to understand the role of quorum sensing and quorum-sensing-related regulatory elements in D. zeae MS2, we sequenced its genome and queried the sequence for genes encoding LuxR homologs. We identified a canonical LuxR-LuxI homolog pair similar to those in other members of the genus Dickeya The quorum-sensing signal for this pair was N-3-oxo-hexanoyl-homoserine lactone, and the circuit affected motility, cell clumping, and production of the pigment indigoidine, but it did not affect infections of banana seedlings in our experiments. We also identified a luxR homolog linked to a gene annotated as encoding a proline iminopeptidase. Similar linked pairs have been associated with virulence in other plant pathogens. We show that mutants with deletions in the proline iminopeptidase gene are attenuated for virulence. Surprisingly, a mutant with a deletion in the gene encoding the LuxR homolog shows normal virulence.IMPORTANCEDickeya zeae is an emerging banana soft rot pathogen in China. We used genome sequencing and annotation to create an inventory of potential virulence factors and virulence gene regulators encoded in Dickeya zeae MS2, a particularly virulent strain. We created mutations in several genes and tested these mutants in a banana seedling infection model. A strain with a mutated proline iminopeptidase gene, homologs of which are important for disease in the Xanthomonas species phytopathogens, was attenuated for soft rot symptoms in our model. Understanding how the proline iminopeptidase functions as a virulence factor may lead to insights about how to control the disease, and it is of general importance as homologs of the proline iminopeptidase occur in dozens of plant-associated bacteria.
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Affiliation(s)
- Luwen Feng
- Guangdong Province Sociomicrobiology Basic Science and Frontier Technology Research Team & Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, People's Republic of China
| | - Amy L Schaefer
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Ming Hu
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, People's Republic of China
| | - Ruiyi Chen
- Guangdong Province Sociomicrobiology Basic Science and Frontier Technology Research Team & Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, People's Republic of China
| | - E Peter Greenberg
- Guangdong Province Sociomicrobiology Basic Science and Frontier Technology Research Team & Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, People's Republic of China
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Jianuan Zhou
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, People's Republic of China
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Gregory K, Salvador LA, Akbar S, Adaikpoh BI, Stevens DC. Survey of Biosynthetic Gene Clusters from Sequenced Myxobacteria Reveals Unexplored Biosynthetic Potential. Microorganisms 2019; 7:E181. [PMID: 31238501 PMCID: PMC6616573 DOI: 10.3390/microorganisms7060181] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/20/2019] [Accepted: 06/21/2019] [Indexed: 01/31/2023] Open
Abstract
Coinciding with the increase in sequenced bacteria, mining of bacterial genomes for biosynthetic gene clusters (BGCs) has become a critical component of natural product discovery. The order Myxococcales, a reputable source of biologically active secondary metabolites, spans three suborders which all include natural product producing representatives. Utilizing the BiG-SCAPE-CORASON platform to generate a sequence similarity network that contains 994 BGCs from 36 sequenced myxobacteria deposited in the antiSMASH database, a total of 843 BGCs with lower than 75% similarity scores to characterized clusters within the MIBiG database are presented. This survey provides the biosynthetic diversity of these BGCs and an assessment of the predicted chemical space yet to be discovered. Considering the mere snapshot of myxobacteria included in this analysis, these untapped BGCs exemplify the potential for natural product discovery from myxobacteria.
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Affiliation(s)
- Katherine Gregory
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| | - Laura A Salvador
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| | - Shukria Akbar
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| | - Barbara I Adaikpoh
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| | - D Cole Stevens
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
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Buijs Y, Bech PK, Vazquez-Albacete D, Bentzon-Tilia M, Sonnenschein EC, Gram L, Zhang SD. Marine Proteobacteria as a source of natural products: advances in molecular tools and strategies. Nat Prod Rep 2019; 36:1333-1350. [DOI: 10.1039/c9np00020h] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review covers the recent advances in molecular tools and strategies for studies and use of natural products from marine Proteobacteria.
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Affiliation(s)
- Yannick Buijs
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
| | - Pernille Kjersgaard Bech
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
| | - Dario Vazquez-Albacete
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
| | - Mikkel Bentzon-Tilia
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
| | - Eva C. Sonnenschein
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
| | - Lone Gram
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
| | - Sheng-Da Zhang
- Department of Biotechnology and Biomedicine
- Technical University of Denmark
- DK-2800 Kgs Lyngby
- Denmark
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Exploration of the Biosynthetic Potential of the Populus Microbiome. mSystems 2018; 3:mSystems00045-18. [PMID: 30320216 PMCID: PMC6172771 DOI: 10.1128/msystems.00045-18] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 08/17/2018] [Indexed: 01/13/2023] Open
Abstract
The plant root microbiome is one of the most diverse and abundant biological communities known. Plant-associated bacteria can have a profound effect on plant growth and development, and especially on protection from disease and environmental stress. These organisms are also known to be a rich source of antibiotic and antifungal drugs. In order to better understand the ways bacterial communities influence plant health, we evaluated the diversity and uniqueness of the natural product gene clusters in bacteria isolated from poplar trees. The complex molecule clusters are abundant, and the majority are unique, suggesting a great potential to discover new molecules that could not only affect plant health but also could have applications as antibiotic agents. Natural products (NPs) isolated from bacteria have dramatically advanced human society, especially in medicine and agriculture. The rapidity and ease of genome sequencing have enabled bioinformatics-guided NP discovery and characterization. As a result, NP potential and diversity within a complex community, such as the microbiome of a plant, are rapidly expanding areas of scientific exploration. Here, we assess biosynthetic diversity in the Populus microbiome by analyzing both bacterial isolate genomes and metagenome samples. We utilize the fully sequenced genomes of isolates from the Populus root microbiome to characterize a subset of organisms for NP potential. The more than 3,400 individual gene clusters identified in 339 bacterial isolates, including 173 newly sequenced organisms, were diverse across NP types and distinct from known NP clusters. The ribosomally synthesized and posttranslationally modified peptides were both widespread and divergent from previously characterized molecules. Lactones and siderophores were prevalent in the genomes, suggesting a high level of communication and pressure to compete for resources. We then consider the overall bacterial diversity and NP variety of metagenome samples compared to the sequenced isolate collection and other plant microbiomes. The sequenced collection, curated to reflect the phylogenetic diversity of the Populus microbiome, also reflects the overall NP diversity trends seen in the metagenomic samples. In our study, only about 1% of all clusters from sequenced isolates were positively matched to a previously characterized gene cluster, suggesting a great opportunity for the discovery of novel NPs involved in communication and control in the Populus root microbiome. IMPORTANCE The plant root microbiome is one of the most diverse and abundant biological communities known. Plant-associated bacteria can have a profound effect on plant growth and development, and especially on protection from disease and environmental stress. These organisms are also known to be a rich source of antibiotic and antifungal drugs. In order to better understand the ways bacterial communities influence plant health, we evaluated the diversity and uniqueness of the natural product gene clusters in bacteria isolated from poplar trees. The complex molecule clusters are abundant, and the majority are unique, suggesting a great potential to discover new molecules that could not only affect plant health but also could have applications as antibiotic agents.
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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: 160] [Impact Index Per Article: 26.7] [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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