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Santos-Júnior CD, Torres MDT, Duan Y, Rodríguez Del Río Á, Schmidt TSB, Chong H, Fullam A, Kuhn M, Zhu C, Houseman A, Somborski J, Vines A, Zhao XM, Bork P, Huerta-Cepas J, de la Fuente-Nunez C, Coelho LP. Discovery of antimicrobial peptides in the global microbiome with machine learning. Cell 2024; 187:3761-3778.e16. [PMID: 38843834 DOI: 10.1016/j.cell.2024.05.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 04/11/2024] [Accepted: 05/06/2024] [Indexed: 06/25/2024]
Abstract
Novel antibiotics are urgently needed to combat the antibiotic-resistance crisis. We present a machine-learning-based approach to predict antimicrobial peptides (AMPs) within the global microbiome and leverage a vast dataset of 63,410 metagenomes and 87,920 prokaryotic genomes from environmental and host-associated habitats to create the AMPSphere, a comprehensive catalog comprising 863,498 non-redundant peptides, few of which match existing databases. AMPSphere provides insights into the evolutionary origins of peptides, including by duplication or gene truncation of longer sequences, and we observed that AMP production varies by habitat. To validate our predictions, we synthesized and tested 100 AMPs against clinically relevant drug-resistant pathogens and human gut commensals both in vitro and in vivo. A total of 79 peptides were active, with 63 targeting pathogens. These active AMPs exhibited antibacterial activity by disrupting bacterial membranes. In conclusion, our approach identified nearly one million prokaryotic AMP sequences, an open-access resource for antibiotic discovery.
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Affiliation(s)
- Célio Dias Santos-Júnior
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China; Laboratory of Microbial Processes & Biodiversity - LMPB, Department of Hydrobiology, Universidade Federal de São Carlos - UFSCar, São Carlos, São Paulo 13565-905, Brazil
| | - Marcelo D T Torres
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA; Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA; Penn Institute for Computational Science, University of Pennsylvania, Philadelphia, PA, USA
| | - Yiqian Duan
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China
| | - Álvaro Rodríguez Del Río
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo-UPM, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Thomas S B Schmidt
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany; APC Microbiome & School of Medicine, University College Cork, Cork, Ireland
| | - Hui Chong
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China
| | - Anthony Fullam
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Michael Kuhn
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Chengkai Zhu
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China
| | - Amy Houseman
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China
| | - Jelena Somborski
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China
| | - Anna Vines
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China
| | - Xing-Ming Zhao
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China; Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China; State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Fudan University, Shanghai, China; MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Peer Bork
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany; Max Delbrück Centre for Molecular Medicine, Berlin, Germany; Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Jaime Huerta-Cepas
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo-UPM, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Cesar de la Fuente-Nunez
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA; Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA; Penn Institute for Computational Science, University of Pennsylvania, Philadelphia, PA, USA.
| | - Luis Pedro Coelho
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai 200433, China; Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology, Translational Research Institute, Woolloongabba, QLD, Australia.
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Chen S, Dai Y, Ke J, Luo Y, Wang C, Hao Y, Zhang A, Han J, Xiang H. Halocin H4 is activated through cleavage by halolysin HlyR4. Appl Environ Microbiol 2024; 90:e0228423. [PMID: 38445904 PMCID: PMC11022586 DOI: 10.1128/aem.02284-23] [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: 12/19/2023] [Accepted: 02/19/2024] [Indexed: 03/07/2024] Open
Abstract
Halocins are antimicrobial peptides secreted by haloarchaea capable of inhibiting the growth of other haloarchaea or bacteria. Halocin H4 (HalH4) is secreted by the model halophilic archaeon Haloferax mediterranei ATCC 33500. Despite attempts to express halH4 heterologously in Escherichia coli and subsequent careful renaturation procedures commonly employed for haloarchaeal proteins, no active halocin was obtained. However, it was discovered that the antihaloarchaeal activity of this halocin could be activated through cleavage by halolysin R4 (HlyR4), a serine protease also secreted by Hfx. mediterranei ATCC 33500. Replacement of the cysteine at the number 115 amino acid with glycine and deletion of the internal trans-membrane region (15 aa) markedly abolished HalH4's antihaloarchaeal activity. Compared to the N-terminus, the C-terminal amino acid sequence was found to be more crucial for HalH4 to exert its antihaloarchaeal activity. Mass spectrometry analysis revealed that the biologically active antihaloarchaeal peptide produced after hydrolytic cleavage by HlyR4 was the C-terminus of HalH4, suggesting a potential mechanism of action involving pore formation within competitor species' cell membranes. Taken together, this study offers novel insights into the interplay between halocins and secreted proteases, as well as their contribution to antagonistic interaction within haloarchaea. IMPORTANCE The antihaloarchaeal function of halocin H4 (HalH4) can be activated by extracellular proteases from haloarchaea, as demonstrated in this study. Notably, we report the first instance of halocin activation through proteolytic cleavage, highlighting its significance in the field. The C-terminus of HalH4 (CTH4) has been identified as the antihaloarchaeal peptide present in hydrolysates generated by HlyR4. The CTH4 exhibited inhibitory activity against a range of haloarchaeal species (Haloarchaeobius spp., Haloarcula spp., Haloferax spp., Halorubellus spp., and Halorubrum spp.), as well as selected bacterial species (Aliifodinibius spp. and Salicola spp.), indicating its broad-spectrum inhibitory potential across domains. The encoding gene of halocin HalH4, halH4, from the model halophilic archaeon Haloferax mediterranei ATCC 33500 can be expressed in Escherichia coli without codon optimization.
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Affiliation(s)
- Shaoxing Chen
- College of Life Sciences, Anhui Normal University, Wuhu, China
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
| | - Yongpei Dai
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Juntao Ke
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Yuqing Luo
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Chuangming Wang
- College of Biological and Agricultural Sciences, Honghe University, Mengzi, China
| | - Yuling Hao
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Aodi Zhang
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Jing Han
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing, China
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Arbulu S, Kjos M. Revisiting the Multifaceted Roles of Bacteriocins : The Multifaceted Roles of Bacteriocins. MICROBIAL ECOLOGY 2024; 87:41. [PMID: 38351266 PMCID: PMC10864542 DOI: 10.1007/s00248-024-02357-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 02/01/2024] [Indexed: 02/16/2024]
Abstract
Bacteriocins are gene-encoded antimicrobial peptides produced by bacteria. These peptides are heterogeneous in terms of structure, antimicrobial activities, biosynthetic clusters, and regulatory mechanisms. Bacteriocins are widespread in nature and may contribute to microbial diversity due to their capacity to target specific bacteria. Primarily studied as food preservatives and therapeutic agents, their function in natural settings is however less known. This review emphasizes the ecological significance of bacteriocins as multifunctional peptides by exploring bacteriocin distribution, mobility, and their impact on bacterial population dynamics and biofilms.
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Affiliation(s)
- Sara Arbulu
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway.
| | - Morten Kjos
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway.
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Santos-Júnior CD, Der Torossian Torres M, Duan Y, del Río ÁR, Schmidt TS, Chong H, Fullam A, Kuhn M, Zhu C, Houseman A, Somborski J, Vines A, Zhao XM, Bork P, Huerta-Cepas J, de la Fuente-Nunez C, Coelho LP. Computational exploration of the global microbiome for antibiotic discovery. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.31.555663. [PMID: 37693522 PMCID: PMC10491242 DOI: 10.1101/2023.08.31.555663] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Novel antibiotics are urgently needed to combat the antibiotic-resistance crisis. We present a machine learning-based approach to predict prokaryotic antimicrobial peptides (AMPs) by leveraging a vast dataset of 63,410 metagenomes and 87,920 microbial genomes. This led to the creation of AMPSphere, a comprehensive catalog comprising 863,498 non-redundant peptides, the majority of which were previously unknown. We observed that AMP production varies by habitat, with animal-associated samples displaying the highest proportion of AMPs compared to other habitats. Furthermore, within different human-associated microbiota, strain-level differences were evident. To validate our predictions, we synthesized and experimentally tested 50 AMPs, demonstrating their efficacy against clinically relevant drug-resistant pathogens both in vitro and in vivo. These AMPs exhibited antibacterial activity by targeting the bacterial membrane. Additionally, AMPSphere provides valuable insights into the evolutionary origins of peptides. In conclusion, our approach identified AMP sequences within prokaryotic microbiomes, opening up new avenues for the discovery of antibiotics.
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Affiliation(s)
- Célio Dias Santos-Júnior
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Marcelo Der Torossian Torres
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania; Philadelphia, Pennsylvania, United States of America
- Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania; Philadelphia, Pennsylvania, United States of America
- Penn Institute for Computational Science, University of Pennsylvania; Philadelphia, Pennsylvania, United States of America
| | - Yiqian Duan
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Álvaro Rodríguez del Río
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo-UPM, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Thomas S.B. Schmidt
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Hui Chong
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Anthony Fullam
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Michael Kuhn
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Chengkai Zhu
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Amy Houseman
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Jelena Somborski
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Anna Vines
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
| | - Xing-Ming Zhao
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Fudan University, Shanghai, China
- MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence
- MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
- International Human Phenome Institute, Shanghai, China
| | - Peer Bork
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Max Delbrück Centre for Molecular Medicine, Berlin, Germany
- Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Jaime Huerta-Cepas
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo-UPM, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Cesar de la Fuente-Nunez
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania; Philadelphia, Pennsylvania, United States of America
- Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania; Philadelphia, Pennsylvania, United States of America
- Penn Institute for Computational Science, University of Pennsylvania; Philadelphia, Pennsylvania, United States of America
| | - Luis Pedro Coelho
- Institute of Science and Technology for Brain-Inspired Intelligence - ISTBI, Fudan University, Shanghai, China
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Ri CH, Li SR, Paek CI, Kim YS. Functional expression of an antimicrobial peptide, belonging to halocin C8 family, from Natrinema sp. RNS21 in Escherichia coli. Extremophiles 2023; 27:21. [PMID: 37548679 DOI: 10.1007/s00792-023-01308-0] [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: 04/06/2023] [Accepted: 07/25/2023] [Indexed: 08/08/2023]
Abstract
Halocins, the proteinaceous antimicrobial agents produced by haloarchaea, may be used for the preservation of salted foods and the treatment of diseases. For their application and function explanation, it is necessary to produce the active recombinants. In this work, a haloarchaeal strain producing halocin was isolated from the salt-fermented shrimp and identified as Natrinema sp. RNS21 by 16S rRNA gene sequence analysis. From 1 L of RNS21 culture, about 0.32 mg of halocin with 96% purity was obtained. Based on the molecular weight, stability and amino acid sequence alignment, the antimicrobial peptide belonged to the halocin C8 (HalC8) family. HalC8 was expressed by fusion with glutathione-S-transferase (GST) in E. coli, followed by affinity purification and enterokinase (EK) cleavage. About 6.2 mg of recombinant HalC8 with 95% purity was obtained from 1 L of E. coli culture. MALDI-TOF-MS and RP-HPLC analysis indicated that the molecular weight and folding pattern of purified recombinant HalC8 were the same as those of native HalC8. Recombinant HalC8 showed obvious inhibitory activity against Haloferax volcanii. Contrast to native HalC8, the active recombinant HalC8 could be easily produced in a short time with a high yield.
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Affiliation(s)
- Chang Ho Ri
- Faculty of Life Science, KIM IL SUNG University, Pyongyang, Democratic People's Republic of Korea.
| | - Song Ryong Li
- Faculty of Life Science, Kim Hyong Jik University of Education, Pyongyang, Democratic People's Republic of Korea
| | - Chon Il Paek
- Faculty of Life Science, KIM IL SUNG University, Pyongyang, Democratic People's Republic of Korea
| | - Yu Sin Kim
- Faculty of Life Science, KIM IL SUNG University, Pyongyang, Democratic People's Republic of Korea
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Moopantakath J, Imchen M, Anju VT, Busi S, Dyavaiah M, Martínez-Espinosa RM, Kumavath R. Bioactive molecules from haloarchaea: Scope and prospects for industrial and therapeutic applications. Front Microbiol 2023; 14:1113540. [PMID: 37065149 PMCID: PMC10102575 DOI: 10.3389/fmicb.2023.1113540] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/14/2023] [Indexed: 04/03/2023] Open
Abstract
Marine environments and salty inland ecosystems encompass various environmental conditions, such as extremes of temperature, salinity, pH, pressure, altitude, dry conditions, and nutrient scarcity. The extremely halophilic archaea (also called haloarchaea) are a group of microorganisms requiring high salt concentrations (2-6 M NaCl) for optimal growth. Haloarchaea have different metabolic adaptations to withstand these extreme conditions. Among the adaptations, several vesicles, granules, primary and secondary metabolites are produced that are highly significant in biotechnology, such as carotenoids, halocins, enzymes, and granules of polyhydroxyalkanoates (PHAs). Among halophilic enzymes, reductases play a significant role in the textile industry and the degradation of hydrocarbon compounds. Enzymes like dehydrogenases, glycosyl hydrolases, lipases, esterases, and proteases can also be used in several industrial procedures. More recently, several studies stated that carotenoids, gas vacuoles, and liposomes produced by haloarchaea have specific applications in medicine and pharmacy. Additionally, the production of biodegradable and biocompatible polymers by haloarchaea to store carbon makes them potent candidates to be used as cell factories in the industrial production of bioplastics. Furthermore, some haloarchaeal species can synthesize nanoparticles during heavy metal detoxification, thus shedding light on a new approach to producing nanoparticles on a large scale. Recent studies also highlight that exopolysaccharides from haloarchaea can bind the SARS-CoV-2 spike protein. This review explores the potential of haloarchaea in the industry and biotechnology as cellular factories to upscale the production of diverse bioactive compounds.
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Affiliation(s)
- Jamseel Moopantakath
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kerala, India
| | - Madangchanok Imchen
- Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry, India
| | - V. T. Anju
- Department of Biochemistry and Molecular Biology, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Siddhardha Busi
- Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Madhu Dyavaiah
- Department of Biochemistry and Molecular Biology, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Rosa María Martínez-Espinosa
- Biochemistry, Molecular Biology, Edaphology and Agricultural Chemistry Department, Faculty of Sciences, University of Alicante, Alicante, Spain
- Multidisciplinary Institute for Environmental Studies “Ramón Margalef”, University of Alicante, Alicante, Spain
| | - Ranjith Kumavath
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kerala, India
- Department of Biotechnology, School of Life Sciences, Pondicherry University, Puducherry, India
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Recent Antimicrobial Responses of Halophilic Microbes in Clinical Pathogens. Microorganisms 2022; 10:microorganisms10020417. [PMID: 35208871 PMCID: PMC8874722 DOI: 10.3390/microorganisms10020417] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 01/27/2023] Open
Abstract
Microbial pathogens that cause severe infections and are resistant to drugs are simultaneously becoming more active. This urgently calls for novel effective antibiotics. Organisms from extreme environments are known to synthesize novel bioprospecting molecules for biomedical applications due to their peculiar characteristics of growth and physiological conditions. Antimicrobial developments from hypersaline environments, such as lagoons, estuaries, and salterns, accommodate several halophilic microbes. Salinity is a distinctive environmental factor that continuously promotes the metabolic adaptation and flexibility of halophilic microbes for their survival at minimum nutritional requirements. A genetic adaptation to extreme solar radiation, ionic strength, and desiccation makes them promising candidates for drug discovery. More microbiota identified via sequencing and ‘omics’ approaches signify the hypersaline environments where compounds are produced. Microbial genera such as Bacillus, Actinobacteria, Halorubrum and Aspergillus are producing a substantial number of antimicrobial compounds. Several strategies were applied for producing novel antimicrobials from halophiles including a consortia approach. Promising results indicate that halophilic microbes can be utilised as prolific sources of bioactive metabolites with pharmaceutical potentialto expand natural product research towards diverse phylogenetic microbial groups which inhabit salterns. The present study reviews interesting antimicrobial compounds retrieved from microbial sources of various saltern environments, with a discussion of their potency in providing novel drugs against clinically drug-resistant microbes.
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Rani A, Saini KC, Bast F, Varjani S, Mehariya S, Bhatia SK, Sharma N, Funk C. A Review on Microbial Products and Their Perspective Application as Antimicrobial Agents. Biomolecules 2021; 11:biom11121860. [PMID: 34944505 PMCID: PMC8699383 DOI: 10.3390/biom11121860] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 02/06/2023] Open
Abstract
Microorganisms including actinomycetes, archaea, bacteria, fungi, yeast, and microalgae are an auspicious source of vital bioactive compounds. In this review, the existing research regarding antimicrobial molecules from microorganisms is summarized. The potential antimicrobial compounds from actinomycetes, particularly Streptomyces spp.; archaea; fungi including endophytic, filamentous, and marine-derived fungi, mushroom; and microalgae are briefly described. Furthermore, this review briefly summarizes bacteriocins, halocins, sulfolobicin, etc., that target multiple-drug resistant pathogens and considers next-generation antibiotics. This review highlights the possibility of using microorganisms as an antimicrobial resource for biotechnological, nutraceutical, and pharmaceutical applications. However, more investigations are required to isolate, separate, purify, and characterize these bioactive compounds and transfer these primary drugs into clinically approved antibiotics.
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Affiliation(s)
- Alka Rani
- Department of Botany, School of Basic and Applied Sciences, Central University of Punjab, Bathinda 151401, India; (A.R.); (K.C.S.)
| | - Khem Chand Saini
- Department of Botany, School of Basic and Applied Sciences, Central University of Punjab, Bathinda 151401, India; (A.R.); (K.C.S.)
| | - Felix Bast
- Department of Botany, School of Basic and Applied Sciences, Central University of Punjab, Bathinda 151401, India; (A.R.); (K.C.S.)
- Correspondence: (F.B.); (S.M.); (S.K.B.)
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar 382010, India;
| | - Sanjeet Mehariya
- Department of Chemistry, Umeå University, 90187 Umeå, Sweden;
- Correspondence: (F.B.); (S.M.); (S.K.B.)
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Korea
- Correspondence: (F.B.); (S.M.); (S.K.B.)
| | - Neeta Sharma
- ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Department of Sustainability-CR Trisaia, SS Jonica 106, km 419 + 500, 75026 Rotondella, Italy;
| | - Christiane Funk
- Department of Chemistry, Umeå University, 90187 Umeå, Sweden;
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Heilbronner S, Krismer B, Brötz-Oesterhelt H, Peschel A. The microbiome-shaping roles of bacteriocins. Nat Rev Microbiol 2021; 19:726-739. [PMID: 34075213 DOI: 10.1038/s41579-021-00569-w] [Citation(s) in RCA: 147] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2021] [Indexed: 02/05/2023]
Abstract
The microbiomes on human body surfaces affect health in multiple ways. They include not only commensal or mutualistic bacteria but also potentially pathogenic bacteria, which can enter sterile tissues to cause invasive infection. Many commensal bacteria produce small antibacterial molecules termed bacteriocins that have the capacity to eliminate specific colonizing pathogens; as such, bacteriocins have attracted increased attention as potential microbiome-editing tools. Metagenome-based and activity-based screening approaches have strongly expanded our knowledge of the abundance and diversity of bacteriocin biosynthetic gene clusters and the properties of a continuously growing list of bacteriocin classes. The dynamic acquisition, diversification or loss of bacteriocin genes can shape the fitness of a bacterial strain that is in competition with bacteriocin-susceptible bacteria. However, a bacteriocin can only provide a competitive advantage if its fitness benefit exceeds the metabolic cost of production, if it spares crucial mutualistic partner strains and if major competitors cannot develop resistance. In contrast to most currently available antibiotics, many bacteriocins have only narrow activity ranges and could be attractive agents for precision therapy and prevention of infections. A common scientific strategy involving multiple disciplines is needed to uncover the immense potential of microbiome-shaping bacteriocins.
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Affiliation(s)
- Simon Heilbronner
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Infection Biology, University of Tübingen, Tübingen, Germany. .,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.
| | - Bernhard Krismer
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Infection Biology, University of Tübingen, Tübingen, Germany.,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany
| | - Heike Brötz-Oesterhelt
- Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.,Interfaculty Institute of Microbiology and Infection Medicine, Department of Microbial Bioactive Compounds, University of Tübingen, Tübingen, Germany
| | - Andreas Peschel
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Infection Biology, University of Tübingen, Tübingen, Germany. .,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.
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Lach J, Jęcz P, Strapagiel D, Matera-Witkiewicz A, Stączek P. The Methods of Digging for "Gold" within the Salt: Characterization of Halophilic Prokaryotes and Identification of Their Valuable Biological Products Using Sequencing and Genome Mining Tools. Genes (Basel) 2021; 12:1756. [PMID: 34828362 PMCID: PMC8619533 DOI: 10.3390/genes12111756] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/18/2021] [Accepted: 10/30/2021] [Indexed: 02/06/2023] Open
Abstract
Halophiles, the salt-loving organisms, have been investigated for at least a hundred years. They are found in all three domains of life, namely Archaea, Bacteria, and Eukarya, and occur in saline and hypersaline environments worldwide. They are already a valuable source of various biomolecules for biotechnological, pharmaceutical, cosmetological and industrial applications. In the present era of multidrug-resistant bacteria, cancer expansion, and extreme environmental pollution, the demand for new, effective compounds is higher and more urgent than ever before. Thus, the unique metabolism of halophilic microorganisms, their low nutritional requirements and their ability to adapt to harsh conditions (high salinity, high pressure and UV radiation, low oxygen concentration, hydrophobic conditions, extreme temperatures and pH, toxic compounds and heavy metals) make them promising candidates as a fruitful source of bioactive compounds. The main aim of this review is to highlight the nucleic acid sequencing experimental strategies used in halophile studies in concert with the presentation of recent examples of bioproducts and functions discovered in silico in the halophile's genomes. We point out methodological gaps and solutions based on in silico methods that are helpful in the identification of valuable bioproducts synthesized by halophiles. We also show the potential of an increasing number of publicly available genomic and metagenomic data for halophilic organisms that can be analysed to identify such new bioproducts and their producers.
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Affiliation(s)
- Jakub Lach
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 93-338 Lodz, Poland; (P.J.); (P.S.)
- Biobank Lab, Department of Molecular Biophysics, Faculty of Environmental Protection, University of Lodz, 93-338 Lodz, Poland;
| | - Paulina Jęcz
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 93-338 Lodz, Poland; (P.J.); (P.S.)
| | - Dominik Strapagiel
- Biobank Lab, Department of Molecular Biophysics, Faculty of Environmental Protection, University of Lodz, 93-338 Lodz, Poland;
| | - Agnieszka Matera-Witkiewicz
- Screening Laboratory of Biological Activity Tests and Collection of Biological Material, Faculty of Pharmacy, Wroclaw Medical University, 50-368 Wroclaw, Poland;
| | - Paweł Stączek
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 93-338 Lodz, Poland; (P.J.); (P.S.)
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11
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Kumar V, Singh B, van Belkum MJ, Diep DB, Chikindas ML, Ermakov AM, Tiwari SK. Halocins, natural antimicrobials of Archaea: Exotic or special or both? Biotechnol Adv 2021; 53:107834. [PMID: 34509601 DOI: 10.1016/j.biotechadv.2021.107834] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/31/2021] [Accepted: 09/06/2021] [Indexed: 01/16/2023]
Abstract
Haloarchaea are adapted to survive under extreme saline conditions by accumulating osmolytes and salts to counteract the high osmotic pressure in their habitats. As a consequence, their proteins have evolved to remain active, or even most active, at very high ionic strength. Halocins are proteinaceous antimicrobial substances that are ribosomally-synthesized by haloarchaea and they provide the producers an advantage in the competition for nutrients and ecological niches. These antimicrobials are stable at high temperature, elevated salt concentrations, and alkaline pH conditions. These properties have endowed them with great potential in diverse biotechnological applications, which involve extreme processing conditions (such as high salt concentrations, high pressure, or high temperatures). They kill target cells by inhibition of Na+/H+ antiporter in the membrane or modification/disruption of the cell membrane leading to cell lysis. In general, the taxonomy of haloarchaea and their typical phenotypic and genotypic characteristics are well studied; however, information regarding their halocins, especially aspects related to genetics, biosynthetic pathways, mechanism of action, and structure-function relationship is very limited. A few studies have demonstrated the potential applications of halocins in the preservation of salted food products and brine-cured hides in leather industries, protecting the myocardium from ischemia and reperfusion injury, as well as from life-threatening diseases such as cardiac arrest and cancers. In recent years, genome mining has been an essential tool to decipher the genetic basis of halocin biosynthesis. Nevertheless, this is likely the tip of the iceberg as genome analyses have revealed many putative halocins in databases waiting for further investigation. Identification and characterization of this source of halocins may lead to antimicrobials for future therapeutics and/or food preservation. Hence, the present review analyzes different aspects of halocins such as biosynthesis, mechanism of action against target cells, and potential biotechnological applications.
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Affiliation(s)
- Vijay Kumar
- Department of Genetics, Maharshi Dayanand University, Rohtak 124001, Haryana, India; Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Bijender Singh
- Department of Biotechnology, Central University of Haryana, Jant-Pali 123031, Mahendergarh, Haryana, India; Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana, India
| | - Marco J van Belkum
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Dzung B Diep
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås 1430, Norway
| | - Michael L Chikindas
- Health Promoting Naturals Laboratory, School of Environmental and Biological Sciences, Rutgers, the State University of New Jersey, New Brunswick, New Jersey 08901, USA; Center for Agrobiotechnology, Don State Technical University, Rostov-on-Don 344002, Russia; I. M. Sechenov First Moscow State Medical University, Moscow 119435, Russia
| | - Alexey M Ermakov
- I. M. Sechenov First Moscow State Medical University, Moscow 119435, Russia
| | - Santosh Kumar Tiwari
- Department of Genetics, Maharshi Dayanand University, Rohtak 124001, Haryana, India.
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12
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Identification of Multi-Potent Protein Subtilisin A from halophilic bacterium Bacillus firmus VE2. Microb Pathog 2021; 157:105007. [PMID: 34044052 DOI: 10.1016/j.micpath.2021.105007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 11/23/2022]
Abstract
Screening of halophiles with antimicrobial activity in saltpan soil samples from Nagapattinam district, Tamil Nadu, revealed isolate VE-2 as the most potent, identified as Bacillus firmus strain VE-2 through 16s rRNA gene sequencing. It had an optimum growth condition (OD 3.1) and antimicrobial protein (AMP) production (450 μg/mL) at 37 °C, pH 8, 25% NaCl, and 36 h incubation. SDS-PAGE analysis of the purified AMP showed the molecular weight of 36 kDa. HPLC analysis of the purified AMP showed different amino acids, such as asparagines, alanine, lysine, proline, threonine, glycine, cysteine, serine, aspartic acid leucine, and valine. Further characterization and identification using FT-IR, 2D-PAGE, MALDI-TOF, and in-silico analysis showed that the isolated AMP had the highest similarity to Subtilisin-A. It showed antibacterial activity against clinical bacterial pathogens like S. aureus, S. pyogenes, C. diphtheria, E. coli, and P. aeruginosa with the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration of 2.5 μg/mL and 20 μg/mL and also against various fungal pathogens such as A. niger, A. flavus, C. albicans, C. tropicalis and C. parapsilosis with the MIC and minimum fungicidal concentrations of 1.25-80 μg/mL. The purified AMP had excellent antioxidant potential, showed a scavenging effect against DPPH and Nitric oxide radicals, and displayed anticancer activity against HeLa cell lines with the IC50 values 53 μg/mL. Hence, the purified bioactive antimicrobial peptides (AMP) could also be used in anticancer therapies.
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13
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de Castro I, Mendo S, Caetano T. Antibiotics from Haloarchaea: What Can We Learn from Comparative Genomics? MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2020; 22:308-316. [PMID: 32048095 DOI: 10.1007/s10126-020-09952-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
The knowledge of antibiotics produced by Archaea (archaeocins) is still limited. So far, only two types of archaeocins are known: (i) sulfolobicins, produced by the extremely thermophilic Sulfolobus spp. and (ii) haloarcheocins, produced by halophilic archaea. Haloarcheocins were first discovered in the 1980s, but most of their characterisation was solely based on supernatant-based assays. Only a few were successfully purified and sequenced, and even fewer have a proposed biosynthetic model. Furthermore, their mode of action, ecological role and biotechnological potential are still to be explored. Haloarcheocin C8 (HalC8) is the best well-characterised haloarcheocin. We applied an approach of comparative genomics in order to go a step further in the knowledge of their biosynthetic clusters as well as the clusters encoding HalC8-like peptides. These peptides can be classified, at least, into 4 different clades, and there is low gene conservation between them. However, the putative function of some proteins is conserved. These include uncharacterized major facilitator superfamily proteins, transmembrane peptides, DNA-binding transcriptional regulators and proteins with extracellular domains. Our analysis reinforces the association of these proteins with HalC8/HalC8-like biosynthesis. Their functionality is unknown, and, in an era where it is known that haloarchaea are not confined to high salt habitats, the advance in the knowledge of their specialised metabolites will be imperative.
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Affiliation(s)
- Inês de Castro
- Department of Biology and CESAM, University of Aveiro, Aveiro, Portugal
| | - Sónia Mendo
- Department of Biology and CESAM, University of Aveiro, Aveiro, Portugal
| | - Tânia Caetano
- Department of Biology and CESAM, University of Aveiro, Aveiro, Portugal.
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Ghanmi F, Carré-Mlouka A, Zarai Z, Mejdoub H, Peduzzi J, Maalej S, Rebuffat S. The extremely halophilic archaeon Halobacterium salinarum ETD5 from the solar saltern of Sfax (Tunisia) produces multiple halocins. Res Microbiol 2019; 171:80-90. [PMID: 31560985 DOI: 10.1016/j.resmic.2019.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/09/2019] [Accepted: 09/17/2019] [Indexed: 10/26/2022]
Abstract
The extremely halophilic archaeon Halobacterium salinarum strain ETD5 was previously isolated from the solar saltern of Sfax (Tunisia) and shown to encode and express halocin S8. The Hbt. salinarum ETD5 culture supernatant was shown here to exhibit high antimicrobial activity against several halophilic archaea and bacteria of different genera, showing a cross-domain inhibition. The antimicrobial activity was destroyed by proteases, thus pointing to halocins. A bioguided purification procedure was applied using two chromatography steps and antimicrobial assays directed against Halorubrum chaoviator ETR14. In-gel screening assay showed the presence of two antimicrobial bands of approximately 8 and 14 kDa, for which characterization was investigated by N-terminal sequencing and mass spectrometry. The full-length form of halocin S8 that contains 81 amino acids and differs from the 36 amino acid short-length halocin S8 previously described from an uncharacterized haloarchaeon S8a, was identified in the 8 kDa halocin band. A novel halocin that we termed halocin S14 was found in the 14 kDa band. It exhibits amino acid sequence identities with the N-terminally truncated region of the archaeal Mn-superoxide dismutase. These results show that Hbt. salinarum ETD5 produces multiple halocins, a feature that had not been described until now in the domain Archaea.
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Affiliation(s)
- Fadoua Ghanmi
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France; Laboratory of Biodiversity and Aquatic Ecosystems, Ecology and Planktonology, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Alyssa Carré-Mlouka
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France.
| | - Zied Zarai
- Laboratory of Plant Biotechnology, Sfax Faculty of Sciences, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Hafedh Mejdoub
- Laboratory of Plant Biotechnology, Sfax Faculty of Sciences, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Jean Peduzzi
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France.
| | - Sami Maalej
- Laboratory of Biodiversity and Aquatic Ecosystems, Ecology and Planktonology, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Sylvie Rebuffat
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France.
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Wang S, Zheng Z, Zou H, Li N, Wu M. Characterization of the secondary metabolite biosynthetic gene clusters in archaea. Comput Biol Chem 2018; 78:165-169. [PMID: 30530297 DOI: 10.1016/j.compbiolchem.2018.11.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 11/20/2018] [Indexed: 10/27/2022]
Abstract
Secondary metabolites are a range of bioactive compounds yielded by bacteria, fungi and plants, etc. The published archaea genomic data provide the opportunity for efficient identification of secondary metabolite biosynthetic gene clusters (BGCs) by genome mining. However, the study of secondary metabolites in archaea is still rare. By using the antiSMASH, we found two main putative secondary metabolite BGCs, bacteriocin and terpene in 203 Archaea genomes. Compared with the genomes of Euryarchaeota that usually lives in less complexity of environment, the genomes of Crenarchaeota usually contained more abundant bacteriocin. In these archaea genomes, we also found the positive correlation between the abundance of bacteriocin and the abundance of CRISPR spacer, suggesting the bacteriocin might be a crucial component of the innate immune system that defense the microbe living in the common environment. The structure analysis of the bacteriocin gene clusters gave a clue that the assisted genes located at the edge of clusters evolved faster than the core biosynthetic genes. To the best of our knowledge, we are the first to systematically explore the distribution of secondary metabolites in archaea, and the investigation of the relationship between BGC and CRISPR spacer expands our understanding of the evolutionary dynamic of these functional molecules.
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Affiliation(s)
- Shengqin Wang
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Zhihong Zheng
- Translational Medicine Research Institute, Zhejiang University, Hangzhou, China
| | - Huixi Zou
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Nan Li
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Mingjiang Wu
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China.
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Mazguene S, Rossi M, Gogliettino M, Palmieri G, Cocca E, Mirino S, Imadalou-Idres N, Benallaoua S. Isolation and characterization from solar salterns of North Algeria of a haloarchaeon producing a new halocin. Extremophiles 2017; 22:259-270. [PMID: 29288279 DOI: 10.1007/s00792-017-0994-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 12/18/2017] [Indexed: 10/18/2022]
Abstract
Halophilic archaea, thriving in hypersaline environments, synthesize antimicrobial substances with an unknown role, called halocins. It has been suggested that halocin production gives transient competitive advantages to the producer strains and represents one of the environmental factors influencing the microbial community composition. Herein, we report on the antibacterial activity of a new haloarchaeon selected from solar salterns of the northern coast of Algeria. A total of 81 halophilic strains, isolated from the microbial consortia, were screened for the production of antimicrobial compounds by interspecies competition test and against a collection of commercial haloarchaea. On the basis of the partial 16S rRNA sequencing, the most efficient halocin producer was recognized as belonging to Haloferax (Hfx) sp., while the best indicator microorganism, showing high sensitivity toward halocin, was related to Haloarcula genus. The main morphological, physiological and biochemical properties of Hfx were investigated and a partial purification of the produced halocin was allowed to identify it as a surface membrane protein with a molecular mass between 30 and 40 kDa. Therefore, in this study, we isolated a new strain belonging to Haloferax genus and producing a promising antimicrobial compound useful for applications in health and food industries.
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Affiliation(s)
- Souhila Mazguene
- Laboratory of Applied Microbiology (LMA), Faculty of Natural and Life Sciences, University Abderrahmane Mira of Bejaia, Targa Ouzemour, 06000, Bejaïa, Algeria
| | - Mosè Rossi
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino, 80131, Naples, Italy
| | - Marta Gogliettino
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino, 80131, Naples, Italy
| | - Gianna Palmieri
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino, 80131, Naples, Italy.
| | - Ennio Cocca
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino, 80131, Naples, Italy
| | - Sara Mirino
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino, 80131, Naples, Italy
| | - Nacera Imadalou-Idres
- Laboratory of Applied Microbiology (LMA), Faculty of Natural and Life Sciences, University Abderrahmane Mira of Bejaia, Targa Ouzemour, 06000, Bejaïa, Algeria
| | - Said Benallaoua
- Laboratory of Applied Microbiology (LMA), Faculty of Natural and Life Sciences, University Abderrahmane Mira of Bejaia, Targa Ouzemour, 06000, Bejaïa, Algeria
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