1
|
Tiwari P, Thakkar S, Dufossé L. Antimicrobials from endophytes as novel therapeutics to counter drug-resistant pathogens. Crit Rev Biotechnol 2024:1-27. [PMID: 38710617 DOI: 10.1080/07388551.2024.2342979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 01/29/2024] [Indexed: 05/08/2024]
Abstract
The rapid increase in antimicrobial resistance (AMR) projects a "global emergency" and necessitates a need to discover alternative resources for combating drug-resistant pathogens or "superbugs." One of the key themes in "One Health Concept" is based on the fact that the interconnected network of humans, the environment, and animal habitats majorly contribute to the rapid selection and spread of AMR. Moreover, the injudicious and overuse of antibiotics in healthcare, the environment, and associated disciplines, further aggravates the concern. The prevalence and persistence of AMR contribute to the global economic burden and are constantly witnessing an upsurge due to fewer therapeutic options, rising mortality statistics, and expensive healthcare. The present decade has witnessed the extensive exploration and utilization of bio-based resources in harnessing antibiotics of potential efficacies. The discovery and characterization of diverse chemical entities from endophytes as potent antimicrobials define an important yet less-explored area in natural product-mediated drug discovery. Endophytes-produced antimicrobials show potent efficacies in targeting microbial pathogens and synthetic biology (SB) mediated engineering of endophytes for yield enhancement, forms a prospective area of research. In keeping with the urgent requirements for new/novel antibiotics and growing concerns about pathogenic microbes and AMR, this paper comprehensively reviews emerging trends, prospects, and challenges of antimicrobials from endophytes and their effective production via SB. This literature review would serve as the platform for further exploration of novel bioactive entities from biological organisms as "novel therapeutics" to address AMR.
Collapse
Affiliation(s)
- Pragya Tiwari
- Department of Biotechnology, Yeungnam University, Gyeongsan, Republic of Korea
| | - Shreya Thakkar
- Department of Biotechnology and Bioengineering, Institute of Advanced Research, Gandhinagar, India
| | - Laurent Dufossé
- Laboratoire CHEMBIOPRO (Chimie et Biotechnologie des Produits Naturels), ESIROI Département agroalimentaire, Université de La Réunion, Saint-Denis, France
| |
Collapse
|
2
|
Sundar RDV, Arunachalam S. Xenomyrothecium tongaense PTS8: a rare endophyte of Polianthes tuberosa with salient antagonism against multidrug-resistant pathogens. Front Microbiol 2024; 15:1327190. [PMID: 38435697 PMCID: PMC10906109 DOI: 10.3389/fmicb.2024.1327190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 02/02/2024] [Indexed: 03/05/2024] Open
Abstract
Introduction Endophytes refer to microorganisms residing within the endosphere of plants, particularly perennials, without inflicting noticeable injury or inducing obvious morphological variations to their host plant or host organism. Endophytic fungi, although often overlooked microorganisms, have garnered interest due to their significant biological diversity and ability to produce novel pharmacological substances. Methods In this study, fourteen endophytic fungi retrieved were from the stem of the perennial plant Polianthes tuberosa of the Asparagaceae family. These fungal crude metabolites were tested for antagonistic susceptibility to Multi-Drug Resistant (MDR) pathogens using agar well diffusion, Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC) assays. The chequerboard test was used to assess the synergistic impact of active extract. Results and discussion In early antibacterial screening using the Agar plug diffusion test, three of fourteen endophytes demonstrated antagonism against Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant Enterococcus (VRE). Three isolates were grown in liquid medium and their secondary metabolites were recovered using various organic solvents. Eight extracts from three endophytic fungi displayed antagonism against one or more human pathogens with diameters ranging from 11 to 24 mm. The highest antagonistic effect was obtained in ethyl acetate extract for PTS8 isolate against two MRSA (ATCC 43300, 700699) with 20 ± 0.27 and 22 ± 0.47 mm zones of inhibition, respectively, among different solvent extracts. The extract had MICs of 3.12 ± 0.05 and 1.56 ± 0.05 μg/mL, and MBCs of 50 ± 0.01 and 12.5 ± 0.04 μg/mL, respectively. Antagonism against VRE was 18 ± 0.23 mm Zone of Inhibition (ZOI) with MIC and MBC of 6.25 ± 0.25 and 25 ± 0.01 μg/mL. When ethyl acetate extract was coupled with antibiotics, the chequerboard assay demonstrated a synergistic impact against MDR bacteria. In an antioxidant test, it had an inhibitory impact of 87 ± 0.5% and 88.5 ± 0.5% in 2,2-Diphenyl-1-Picrylhydrazyl and reducing power assay, respectively, at 150 μg/mL concentration. PTS8 was identified as a Xenomyrothecium tongaense strain by 18S rRNA internal transcribed spacer (ITS) sequencing. To our insight, it is the foremost study to demonstrate the presence of an X. tongaense endophyte in the stem of P. tuberosa and the first report to study the antibacterial efficacy of X. tongaense which might serve as a powerful antibacterial source against antibiotic-resistant human infections.
Collapse
Affiliation(s)
- Ranjitha Dhevi V. Sundar
- Laboratory of Microbiology, Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India
- Laboratory of Microbiology, Department of Agriculture Microbiology, VIT School of Agricultural Innovations and Advanced Learning, Vellore Institute of Technology, Vellore, India
| | - Sathiavelu Arunachalam
- Laboratory of Microbiology, Department of Agriculture Microbiology, VIT School of Agricultural Innovations and Advanced Learning, Vellore Institute of Technology, Vellore, India
| |
Collapse
|
3
|
Liu X, Wang Z, You Z, Wang W, Wang Y, Wu W, Peng Y, Zhang S, Yun Y, Zhang J. Transcriptomic analysis of cell envelope inhibition by prodigiosin in methicillin-resistant Staphylococcus aureus. Front Microbiol 2024; 15:1333526. [PMID: 38318338 PMCID: PMC10839101 DOI: 10.3389/fmicb.2024.1333526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Accepted: 01/03/2024] [Indexed: 02/07/2024] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading threat to public health as it is resistant to most currently available antibiotics. Prodigiosin is a secondary metabolite of microorganisms with broad-spectrum antibacterial activity. This study identified a significant antibacterial effect of prodigiosin against MRSA with a minimum inhibitory concentration as low as 2.5 mg/L. The results of scanning electron microscopy, crystal violet staining, and confocal laser scanning microscopy indicated that prodigiosin inhibited biofilm formation in S. aureus USA300, while also destroying the structure of the cell wall and cell membrane, which was confirmed by transmission electron microscopy. At a prodigiosin concentration of 1.25 mg/L, biofilm formation was inhibited by 76.24%, while 2.5 mg/L prodigiosin significantly reduced the vitality of MRSA cells in the biofilm. Furthermore, the transcriptomic results obtained at 1/8 MIC of prodigiosin indicated that 235and 387 genes of S. aureus USA300 were significantly up- and downregulated, respectively. The downregulated genes were related to two-component systems, including the transcriptional regulator LytS, quorum sensing histidine kinases SrrB, NreA and NreB, peptidoglycan biosynthesis enzymes (MurQ and GlmU), iron-sulfur cluster repair protein ScdA, microbial surface components recognizing adaptive matrix molecules, as well as the key arginine synthesis enzymes ArcC and ArgF. The upregulated genes were mainly related to cell wall biosynthesis, as well as two-component systems including vancomycin resistance-associated regulator, lipoteichoic acid biosynthesis related proteins DltD and DltB, as well as the 9 capsular polysaccharide biosynthesis proteins. This study elucidated the molecular mechanisms through which prodigiosin affects the cell envelope of MRSA from the perspectives of cell wall synthesis, cell membrane and biofilm formation, providing new potential targets for the development of antimicrobials for the treatment of MRSA.
Collapse
Affiliation(s)
- Xiaoxia Liu
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| | - Zonglin Wang
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, China
| | - Zhongyu You
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| | - Wei Wang
- Clinical Laboratory of First Hospital of Jiaxing, Jiaxing, China
| | - Yujie Wang
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| | - Wenjing Wu
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| | - Yongjia Peng
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| | - Suping Zhang
- College of Advanced Materials Engineering, Jiaxing Nanhu University, Jiaxing, China
| | - Yinan Yun
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| | - Jin Zhang
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, China
| |
Collapse
|
4
|
Chua RW, Song KP, Ting ASY. Comparative analysis of antimicrobial compounds from endophytic Buergenerula spartinae from orchid. Antonie Van Leeuwenhoek 2023; 116:1057-1072. [PMID: 37597137 DOI: 10.1007/s10482-023-01870-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/08/2023] [Indexed: 08/21/2023]
Abstract
A rare fungal endophyte, identified as Buergenerula spartinae (C28), was isolated from the roots of Cymbidium orchids and was characterised and evaluated for its antimicrobial activities. Bio-guided fractionation revealed 4 fractions from B. spartinae (C28) having antibacterial activities against at least one bacterial pathogen tested (Bacillus cereus and Staphylococcus aureus). However, inhibitory activities were absent against pathogenic fungi (Ganoderma boninense, Pythium ultimum and Fusarium solani). Fraction 2 and fraction 4 of B. spartinae (C28) exhibited potent antibacterial activities against S. aureus (MIC: 0.078 mg/mL) and B. cereus (MIC: 0.313 mg/mL), respectively. LCMS analysis revealed the presence of antibacterial agents and antibiotics in fraction 2 (benoxinate, pyropheophorbide A, (-)-ormosanine and N-undecylbenzenesulfonic acid) and fraction 4 (kaempferol 3-p-coumarate, 6-methoxy naphthalene acetic acid, levofuraltadone, hinokitiol glucoside, 3-α(S)-strictosidine, pyropheophorbide A, 5'-hydroxystreptomycin, kanzonol N and 3-butylidene-7-hydroxyphthalide), which may be responsible for the antibacterial activities observed. Most of the bioactive compounds profiled from the antibacterial fractions were discovered for the first time from endophytic isolates (i.e. from B. spartinae (C28)). Buergenerula spartinae (C28) from Cymbidium sp. is therefore, an untapped resource of bioactive compounds for potential applications in healthcare and commercial industries.
Collapse
Affiliation(s)
- Ru Wei Chua
- School of Science, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Keang Peng Song
- School of Science, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Adeline Su Yien Ting
- School of Science, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor Darul Ehsan, Malaysia.
| |
Collapse
|
5
|
Cadelis MM, Li SA, van de Pas SJ, Grey A, Mulholland D, Weir BS, Copp BR, Wiles S. Antimicrobial Natural Products from Plant Pathogenic Fungi. Molecules 2023; 28:1142. [PMID: 36770808 PMCID: PMC9920077 DOI: 10.3390/molecules28031142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 01/26/2023] Open
Abstract
Isolates of a variety of fungal plant pathogens (Alternaria radicina ICMP 5619, Cercospora beticola ICMP 15907, Dactylonectria macrodidyma ICMP 16789, D. torresensis ICMP 20542, Ilyonectria europaea ICMP 16794, and I. liriodendra ICMP 16795) were screened for antimicrobial activity against the human pathogenic bacteria Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, Mycobacterium abscessus, and M. marinum and were found to have some activity. Investigation of the secondary metabolites of these fungal isolates led to the isolation of ten natural products (1-10) of which one was novel, (E)-4,7-dihydroxyoct-2-enoic acid (1). Structure elucidation of all natural products was achieved by a combination of NMR spectroscopy and mass spectrometry. We also investigated the antimicrobial activity of a number of the isolated natural products. While we did not find (E)-4,7-dihydroxyoct-2-enoic acid (1) to have any activity against the bacteria and fungi in our assays, we did find that cercosporin (7) exhibited potent activity against Methicillin resistant Staphylococcus aureus (MRSA), dehydro-curvularin (6) and radicicol (10) exhibited antimycobacterial activity against M. marinum, and brefeldin A (8) and radicicol (10) exhibited antifungal activity against Candida albicans. Investigation of the cytotoxicity and haemolytic activities of these natural products (6-8 and 10) found that only one of the four active compounds, radicicol (10), was non-cytotoxic and non-haemolytic.
Collapse
Affiliation(s)
- Melissa M. Cadelis
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Bioluminescent Superbugs Lab, School of Medical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Steven A. Li
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Shara J. van de Pas
- Bioluminescent Superbugs Lab, School of Medical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Alex Grey
- Bioluminescent Superbugs Lab, School of Medical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Daniel Mulholland
- Bioluminescent Superbugs Lab, School of Medical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Bevan S. Weir
- Manaaki Whenua—Landcare Research, Private Bag 92170, Auckland 1142, New Zealand
| | - Brent R. Copp
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Siouxsie Wiles
- Bioluminescent Superbugs Lab, School of Medical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Te Pūnaha Matatini Centre of Research Excellence in Complex Systems, Auckland 1142, New Zealand
| |
Collapse
|
6
|
Cadelis M, Grey A, van de Pas S, Geese S, Weir BS, Copp B, Wiles S. Terrien, a metabolite made by Aspergillus terreus, has activity against Cryptococcus neoformans. PeerJ 2022; 10:e14239. [PMID: 36275475 PMCID: PMC9586122 DOI: 10.7717/peerj.14239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 09/23/2022] [Indexed: 01/24/2023] Open
Abstract
Antimicrobial compounds, including antibiotics, have been a cornerstone of modern medicine being able to both treat infections and prevent infections in at-risk people, including those who are immune-compromised and those undergoing routine surgical procedures. Their intense use, including in people, animals, and plants, has led to an increase in the incidence of resistant bacteria and fungi, resulting in a desperate need for novel antimicrobial compounds with new mechanisms of action. Many antimicrobial compounds in current use originate from microbial sources, such as penicillin from the fungus Penicillium chrysogenum (renamed by some as P. rubens). Through a collaboration with Aotearoa New Zealand Crown Research Institute Manaaki Whenua-Landcare Research we have access to a collection of thousands of fungal cultures known as the International Collection of Microorganisms from Plants (ICMP). The ICMP contains both known and novel species which have not been extensively tested for their antimicrobial activity. Initial screening of ICMP isolates for activity against Escherichia coli and Staphylococcus aureus directed our interest towards ICMP 477, an isolate of the soil-inhabiting fungus, Aspergillus terreus. In our investigation of the secondary metabolites of A. terreus, through extraction, fractionation, and purification, we isolated nine known natural products. We evaluated the biological activity of selected compounds against various bacteria and fungi and discovered that terrein (1) has potent activity against the important human pathogen Cryptococcus neoformans.
Collapse
Affiliation(s)
- Melissa Cadelis
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand,Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Alex Grey
- Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Shara van de Pas
- Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Soeren Geese
- Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Bevan S. Weir
- Manaaki Whenua – Landcare Research, Auckland, New Zealand
| | - Brent Copp
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Siouxsie Wiles
- Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| |
Collapse
|