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Rząd K, Kuplińska A, Gabriel I. Fungal L-Methionine Biosynthesis Pathway Enzymes and Their Applications in Various Scientific and Commercial Fields. Biomolecules 2024; 14:1315. [PMID: 39456248 PMCID: PMC11506715 DOI: 10.3390/biom14101315] [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: 08/31/2024] [Revised: 10/08/2024] [Accepted: 10/15/2024] [Indexed: 10/28/2024] Open
Abstract
L-methionine (L-Met) is one of the nine proteinogenic amino acids essential for humans since, in human cells, there are no complete pathways for its biosynthesis from simple precursors. L-Met plays a crucial role in cellular function as it is required for proper protein synthesis, acting as an initiator. Additionally, this amino acid participates in various metabolic processes and serves as a precursor for the synthesis of S-adenosylmethionine (AdoMet), which is involved in the methylation of DNA molecules and phospholipids, as well as in maintaining genome stability. Due to its importance, fungal L-methionine biosynthesis pathway enzymes are being intensively studied. This review presents the current state of the art in terms of their cellular function, usefulness as molecular markers, antifungal targets, or industrial approaches.
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Affiliation(s)
| | | | - Iwona Gabriel
- Department of Pharmaceutical Technology and Biochemistry, Gdansk University of Technology, 80-233 Gdansk, Poland; (K.R.); (A.K.)
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Subash Chandra Bose K, Shah MI, Krishna J, Sankaranarayanan M. Genome-scale metabolic model analysis of Pichia pastoris for enhancing the production of S-adenosyl-L-methionine. Bioprocess Biosyst Eng 2023; 46:1471-1482. [PMID: 37597025 DOI: 10.1007/s00449-023-02913-1] [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: 08/22/2022] [Accepted: 07/21/2023] [Indexed: 08/21/2023]
Abstract
Komagataella phaffii, formerly Pichia pastoris (P. pastoris), is a promising methylotrophic yeast used in industry to produce recombinant protein and valuable metabolites. In this study, a genome-scale metabolic model (GEMs) was reconstructed and used to assess P. pastoris' metabolic capabilities for the production of S-adenosyl-L-methionine (AdoMet or SAM or SAMe) from individual carbon sources along with the addition of L-methionine. In a model-driven P. pastoris strain, the well-established genome-scale metabolic model iAUKM can be implemented to predict high valuable metabolite production. The model, iAUKM, was created by merging the previously published iMT1026 model and the draught model generated using Raven toolbox from the KEGG database which covered 2309 enzymatic reactions associated with 1033 metabolic genes and 1750 metabolites. The highly curated model was successful in capturing P. pastoris growth on various carbon sources, as well as AdoMet production under various growth conditions. Many overexpression gene targets for increasing AdoMet accumulation in the cell have been predicted for various carbon sources. Inorganic phosphatase (IPP) was one of the predicted overexpression targets as revealed from simulations using iAUKM. When IPP gene was integrated into P. pastoris, we found that AdoMet accumulation increased by 16% and 14% using glucose and glycerol as carbon sources, respectively. Our in silico results shed light on the factors limiting AdoMet production, as well as key pathways for rationalized engineering to increase AdoMet yield.
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Affiliation(s)
| | - Mohd Imran Shah
- Department of Biotechnology, Anna University, Chennai, Tamil Nadu, India
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Yu F, Zhao X, Zhou J, Lu W, Li J, Chen J, Du G. Biosynthesis of High-Active Hemoproteins by the Efficient Heme-Supply Pichia Pastoris Chassis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2302826. [PMID: 37649147 PMCID: PMC10602571 DOI: 10.1002/advs.202302826] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/17/2023] [Indexed: 09/01/2023]
Abstract
Microbial synthesis of valuable hemoproteins has become a popular research topic, and Pichia pastoris is a versatile platform for the industrial production of recombinant proteins. However, the inadequate supply of heme limits the synthesis of high-active hemoproteins. Here a strategy for enhancing intracellular heme biosynthesis to improve the titers and functional activities of hemoproteins is reported. After selecting a suitable expressional strategy for globins, the efficient heme-supply P. pastoris chassis is established by removing the spatial segregation during heme biosynthesis, optimizing precursor synthesis, assembling rate-limiting enzymes using protein scaffolds, and inhibiting heme degradation. This robust chassis produces several highly active hemoproteins, including porcine myoglobin, soy hemoglobin, Vitreoscilla hemoglobin, and P450-BM3, which can be used in the development of artificial meat, high-cell-density fermentation, and whole-cell catalytic synthesis of high-value-added compounds. Furthermore, the engineered chassis strain has great potential for producing and applying other hemoproteins with high activities in various fields.
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Affiliation(s)
- Fei Yu
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Xinrui Zhao
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jingwen Zhou
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Wei Lu
- Dongsheng Biotech Co., Ltd.91–92 Junmin RoadTaixingJiangsu225432China
| | - Jianghua Li
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jian Chen
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Guocheng Du
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University1800 Lihu RoadWuxiJiangsu214122China
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Scott J, Amich J. The role of methionine synthases in fungal metabolism and virulence. Essays Biochem 2023; 67:853-863. [PMID: 37449444 DOI: 10.1042/ebc20230007] [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: 05/25/2023] [Revised: 06/20/2023] [Accepted: 06/20/2023] [Indexed: 07/18/2023]
Abstract
Methionine synthases (MetH) catalyse the methylation of homocysteine (Hcy) with 5-methyl-tetrahydrofolate (5, methyl-THF) acting as methyl donor, to form methionine (Met) and tetrahydrofolate (THF). This function is performed by two unrelated classes of enzymes that differ significantly in both their structures and mechanisms of action. The genomes of plants and many fungi exclusively encode cobalamin-independent enzymes (EC.2.1.1.14), while some fungi also possess proteins from the cobalamin-dependent (EC.2.1.1.13) family utilised by humans. Methionine synthase's function connects the methionine and folate cycles, making it a crucial node in primary metabolism, with impacts on important cellular processes such as anabolism, growth and synthesis of proteins, polyamines, nucleotides and lipids. As a result, MetHs are vital for the viability or virulence of numerous prominent human and plant pathogenic fungi and have been proposed as promising broad-spectrum antifungal drug targets. This review provides a summary of the relevance of methionine synthases to fungal metabolism, their potential as antifungal drug targets and insights into the structures of both classes of MetH.
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Affiliation(s)
- Jennifer Scott
- Manchester Fungal Infection Group, Division of Evolution, Infection, and Genomics, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Jorge Amich
- Manchester Fungal Infection Group, Division of Evolution, Infection, and Genomics, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Mycology Reference Laboratory (Laboratorio de Referencia e Investigación en Micología [LRIM]), National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
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Sun X, Liu N, Sun C, Xu Y, Ding D, Kong J. The inhibitory effect of vitamin D on myocardial homocysteine levels involves activation of Nrf2-mediated methionine synthase. J Steroid Biochem Mol Biol 2023; 231:106303. [PMID: 36990164 DOI: 10.1016/j.jsbmb.2023.106303] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 02/18/2023] [Accepted: 03/26/2023] [Indexed: 03/30/2023]
Abstract
BACKGROUND Homocysteine (Hcy) is a synthetic amino acid containing sulfhydryl group, which is an intermediate product of the deep metabolic pathway of methionine and cysteine. The abnormal increase in fasting plasma total Hcy concentration caused by various factors is called hyperhomocysteine (HHcy). HHcy is closely relevant to the occurrence and progression of diverse cardiovascular and cerebrovascular diseases, such as coronary heart disease, hypertension and diabetes, etc. Vitamin D/vitamin D receptor (VDR) pathway is pointed out that prevent cardiovascular disease by reducing serum homocysteine levels. Our research is designed to explore the potential mechanism of vitamin D in the prevention and treatment of HHcy. METHODS AND RESULTS The Hcy and 25(OH)D3 levels in mouse myocardial tissue, serum or myocardial cells were detected using ELISA kits. The expression levels of VDR, Nrf2 and methionine synthase (MTR) were observed using Western blotting, immunohistochemistry and real time polymerase chain reaction (PCR). General information of the mice, including diet, water intake and body weight, was recorded. Vitamin D up-regulated the mRNA and protein expression of Nrf2 and MTR in mouse myocardial tissue and cells. CHIP assay determined that the combination of Nrf2 binding to the S1 site of the MTR promoter in cardiomyocytes using traditional PCR and real time PCR. Dual Luciferase Assay was applied to detect the transcriptional control of Nrf2 on MTR. The up-regulation effect of Nrf2 on MTR was verified by Nrf2 knockout and overexpression in cardiomyocytes. The role of Nrf2 in vitamin D inhibition of Hcy was revealed using Nrf2-knockdown HL-1 cells and Nrf2 heterozygous mice. Western blotting, real time PCR, IHC staining and ELISA showed that Nrf2 deficiency could restrain the increase in MTR expression and the decrease in Hcy level induced by vitamin D. The transcriptional activities of Nrf2/MTR were activated by vitamin D/VDR with a decrease in Hcy. CONCLUSION Vitamin D/VDR upregulates MTR in an Nrf2-dependent manner, thereby reducing the risk of HHcy.
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Affiliation(s)
- Xiaoqi Sun
- Department of Clinical Nutrition, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Ning Liu
- Department of Clinical Nutrition, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Can Sun
- Department of Clinical Nutrition, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Yingxi Xu
- Department of Clinical Nutrition, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Ding Ding
- Department of Clinical Nutrition, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Juan Kong
- Department of Clinical Nutrition, Shengjing Hospital of China Medical University, Shenyang 110004, China.
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Kwolek-Mirek M, Dubicka-Lisowska A, Bednarska S, Zadrag-Tecza R, Kaszycki P. Changes in a Protein Profile Can Account for the Altered Phenotype of the Yeast Saccharomyces cerevisiae Mutant Lacking the Copper-Zinc Superoxide Dismutase. Metabolites 2023; 13:metabo13030459. [PMID: 36984899 PMCID: PMC10056615 DOI: 10.3390/metabo13030459] [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: 02/20/2023] [Revised: 03/14/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Copper-zinc superoxide dismutase (SOD1) is an antioxidant enzyme that catalyzes the disproportionation of superoxide anion to hydrogen peroxide and molecular oxygen (dioxygen). The yeast Saccharomyces cerevisiae lacking SOD1 (Δsod1) is hypersensitive to the superoxide anion and displays a number of oxidative stress-related alterations in its phenotype. We compared proteomes of the wild-type strain and the Δsod1 mutant employing two-dimensional gel electrophoresis and detected eighteen spots representing differentially expressed proteins, of which fourteen were downregulated and four upregulated. Mass spectrometry-based identification enabled the division of these proteins into functional classes related to carbon metabolism, amino acid and protein biosynthesis, nucleotide biosynthesis, and metabolism, as well as antioxidant processes. Detailed analysis of the proteomic data made it possible to account for several important morphological, biochemical, and physiological changes earlier observed for the SOD1 mutation. An example may be the proposed additional explanation for methionine auxotrophy. It is concluded that protein comparative profiling of the Δsod1 yeast may serve as an efficient tool in the elucidation of the mutation-based systemic alterations in the resultant S. cerevisiae phenotype.
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Affiliation(s)
- Magdalena Kwolek-Mirek
- Department of Biology, Institute of Biology and Biotechnology, College of Natural Sciences, University of Rzeszow, 35-601 Rzeszow, Poland
| | - Aleksandra Dubicka-Lisowska
- Department of Plant Biology and Biotechnology, Faculty of Biotechnology and Horticulture, University of Agriculture in Krakow, 31-425 Krakow, Poland
| | - Sabina Bednarska
- Department of Biology, Institute of Biology and Biotechnology, College of Natural Sciences, University of Rzeszow, 35-601 Rzeszow, Poland
| | - Renata Zadrag-Tecza
- Department of Biology, Institute of Biology and Biotechnology, College of Natural Sciences, University of Rzeszow, 35-601 Rzeszow, Poland
| | - Pawel Kaszycki
- Department of Plant Biology and Biotechnology, Faculty of Biotechnology and Horticulture, University of Agriculture in Krakow, 31-425 Krakow, Poland
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Fiołka MJ, Czaplewska P, Wójcik-Mieszawska S, Lewandowska A, Lewtak K, Sofińska-Chmiel W, Buchwald T. Metabolic, structural, and proteomic changes in Candida albicans cells induced by the protein-carbohydrate fraction of Dendrobaena veneta coelomic fluid. Sci Rep 2021; 11:16711. [PMID: 34408181 PMCID: PMC8373886 DOI: 10.1038/s41598-021-96093-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/02/2021] [Indexed: 01/14/2023] Open
Abstract
The isolated protein-polysaccharide fraction (AAF) from the coelomic fluid of Dendrobaena veneta earthworm shows effective activity against Candida albicans yeast. Fungal cells of the clinical strain after incubation with the active fraction were characterized by disturbed cell division and different morphological forms due to the inability to separate the cells from each other. Staining of the cells with acridine orange revealed a change in the pH of the AAF-treated cells. It was observed that, after the AAF treatment, the mitochondrial DNA migrated towards the nuclear DNA, whereupon both merged into a single nuclear structure, which preceded the apoptotic process. Cells with a large nucleus were imaged with the scanning electron cryomicroscopy (Cryo-SEM) technique, while enlarged mitochondria and the degeneration of cell structures were shown by transmission electron microscopy (TEM). The loss of the correct cell shape and cell wall integrity was visualized by both the TEM and SEM techniques. Mass spectrometry and relative quantitative SWATH MS analysis were used to determine the reaction of the C. albicans proteome to the components of the AAF fraction. AAF was observed to influence the expression of mitochondrial and oxidative stress proteins. The oxidative stress in C. albicans cells caused by the action of AAF was demonstrated by fluorescence microscopy, proteomic methods, and XPS spectroscopy. The secondary structure of AAF proteins was characterized by Raman spectroscopy. Analysis of the elemental composition of AAF confirmed the homogeneity of the preparation. The observed action of AAF, which targets not only the cell wall but also the mitochondria, makes the preparation a potential antifungal drug killing the cells of the C. albicans pathogen through apoptosis.
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Affiliation(s)
- Marta J Fiołka
- Department of Immunobiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033, Lublin, Poland.
| | - Paulina Czaplewska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Sylwia Wójcik-Mieszawska
- Department of Immunobiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033, Lublin, Poland
| | - Aleksandra Lewandowska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Kinga Lewtak
- Department of Cell Biology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Weronika Sofińska-Chmiel
- Analytical Laboratory, Institute of Chemical Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Tomasz Buchwald
- Faculty of Materials Science and Technical Physics, Institute of Materials Research and Quantum Engineering, Poznan University of Technology, Poznań, Poland
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Molecular targets for antifungals in amino acid and protein biosynthetic pathways. Amino Acids 2021; 53:961-991. [PMID: 34081205 PMCID: PMC8241756 DOI: 10.1007/s00726-021-03007-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/17/2021] [Indexed: 01/22/2023]
Abstract
Fungi cause death of over 1.5 million people every year, while cutaneous mycoses are among the most common infections in the world. Mycoses vary greatly in severity, there are long-term skin (ringworm), nail or hair infections (tinea capitis), recurrent like vaginal candidiasis or severe, life-threatening systemic, multiorgan infections. In the last few years, increasing importance is attached to the health and economic problems caused by fungal pathogens. There is a growing need for improvement of the availability of antifungal drugs, decreasing their prices and reducing side effects. Searching for novel approaches in this respect, amino acid and protein biosynthesis pathways appear to be competitive. The route that leads from amino acid biosynthesis to protein folding and its activation is rich in enzymes that are descriptive of fungi. Blocking the action of those enzymes often leads to avirulence or growth inhibition. In this review, we want to trace the principal processes of fungi vitality. We present the data of genes encoding enzymes involved in amino acid and protein biosynthesis, potential molecular targets in antifungal chemotherapy, and describe the impact of inhibitors on fungal organisms.
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Targeting Methionine Synthase in a Fungal Pathogen Causes a Metabolic Imbalance That Impacts Cell Energetics, Growth, and Virulence. mBio 2020; 11:mBio.01985-20. [PMID: 33051366 PMCID: PMC7554668 DOI: 10.1128/mbio.01985-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Fungal pathogens are responsible for millions of life-threatening infections on an annual basis worldwide. The current repertoire of antifungal drugs is very limited and, worryingly, resistance has emerged and already become a serious threat to our capacity to treat fungal diseases. The first step to develop new drugs is often to identify molecular targets in the pathogen whose inhibition during infection can prevent its growth. However, the current models are not suitable to validate targets in established infections. Here, we have characterized the promising antifungal target methionine synthase in great detail, using the prominent fungal pathogen Aspergillus fumigatus as a model. We have uncovered the underlying reason for its essentiality and confirmed its druggability. Furthermore, we have optimized the use of a genetic system to show a beneficial effect of targeting methionine synthase in established infections. Therefore, we believe that antifungal drugs to target methionine synthase should be pursued and additionally, we provide a model that permits gaining information about the validity of antifungal targets in established infections. There is an urgent need to develop novel antifungals to tackle the threat fungal pathogens pose to human health. Here, we have performed a comprehensive characterization and validation of the promising target methionine synthase (MetH). We show that in Aspergillus fumigatus the absence of this enzymatic activity triggers a metabolic imbalance that causes a reduction in intracellular ATP, which prevents fungal growth even in the presence of methionine. Interestingly, growth can be recovered in the presence of certain metabolites, which shows that metH is a conditionally essential gene and consequently should be targeted in established infections for a more comprehensive validation. Accordingly, we have validated the use of the tetOFF genetic model in fungal research and improved its performance in vivo to achieve initial validation of targets in models of established infection. We show that repression of metH in growing hyphae halts growth in vitro, which translates into a beneficial effect when targeting established infections using this model in vivo. Finally, a structure-based virtual screening of methionine synthases reveals key differences between the human and fungal structures and unravels features in the fungal enzyme that can guide the design of novel specific inhibitors. Therefore, methionine synthase is a valuable target for the development of new antifungals.
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