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Lyu C, Meng Y, Zhang X, Yang J, Shen B. Two enzymes contribute to citrate production in the mitochondrion of Toxoplasma gondii. J Biol Chem 2024; 300:107565. [PMID: 39002675 PMCID: PMC11359734 DOI: 10.1016/j.jbc.2024.107565] [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: 02/07/2024] [Revised: 06/27/2024] [Accepted: 07/09/2024] [Indexed: 07/15/2024] Open
Abstract
Citrate synthase catalyzes the first and the rate-limiting reaction of the tricarboxylic acid (TCA) cycle, producing citrate from the condensation of oxaloacetate and acetyl-coenzyme A. The parasitic protozoan Toxoplasma gondii has full TCA cycle activity, but its physiological roles remain poorly understood. In this study, we identified three proteins with predicted citrate synthase (CS) activities two of which were localized in the mitochondrion, including the 2-methylcitrate synthase (PrpC) that was thought to be involved in the 2-methylcitrate cycle, an alternative pathway for propionyl-CoA detoxification. Further analyses of the two mitochondrial enzymes showed that both had citrate synthase activity, but the catalytic efficiency of CS1 was much higher than that of PrpC. Consistently, the deletion of CS1 resulted in a significantly reduced flux of glucose-derived carbons into TCA cycle intermediates, leading to decreased parasite growth. In contrast, disruption of PrpC had little effect. On the other hand, simultaneous disruption of both CS1 and PrpC resulted in more severe metabolic changes and growth defects than a single deletion of either gene, suggesting that PrpC does contribute to citrate production under physiological conditions. Interestingly, deleting Δcs1 and Δprpc individually or in combination only mildly or negligibly affected the virulence of parasites in mice, suggesting that both enzymes are dispensable in vivo. The dispensability of CS1 and PrpC suggests that either the TCA cycle is not essential for the asexual reproduction of tachyzoites or there are other routes of citrate supply in the parasite mitochondrion.
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Affiliation(s)
- Congcong Lyu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Yanan Meng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Xin Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Jichao Yang
- College of Life Sciences, Longyan University, Longyan, Fujian, PR China
| | - Bang Shen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China; Hubei Hongshan Laboratory, Wuhan, Hubei Province, PR China; Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Shenzhen, Guangdong Province, PR China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, Guangdong Province, PR China.
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2
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Ott LC, Mellata M. Short-chain fatty acids inhibit bacterial plasmid transfer through conjugation in vitro and in ex vivo chicken tissue explants. Front Microbiol 2024; 15:1414401. [PMID: 38903782 PMCID: PMC11187007 DOI: 10.3389/fmicb.2024.1414401] [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: 04/08/2024] [Accepted: 05/22/2024] [Indexed: 06/22/2024] Open
Abstract
The animal gut acts as a potent reservoir for spreading and maintaining conjugative plasmids that confer antimicrobial resistance (AMR), fitness, and virulence attributes. Interventions that inhibit the continued emergence and expansion of AMR and virulent strains in agricultural and clinical environments are greatly desired. This study aims to determine the presence and efficacy of short-chain fatty acids (SCFA) inhibitory effects on the conjugal transfer of AMR plasmids. In vitro broth conjugations were conducted between donor Escherichia coli strains carrying AMP plasmids and the plasmid-less Escherichia coli HS-4 recipient strain. Conjugations were supplemented with ddH2O or SCFAs at 1, 0.1, 0.01, or 0.001 molar final concentration. The addition of SCFAs completely inhibited plasmid transfer at 1 and 0.1 molar and significantly (p < 0.05) reduced transfer at 0.01 molar, regardless of SCFA tested. In explant models for the chicken ceca, either ddH2O or a final concentration of 0.025 M SCFAs were supplemented to the explants infected with donor and recipient E. coli. In every SCFA tested, significant decreases in transconjugant populations compared to ddH2O-treated control samples were observed with minimal effects on donor and recipient populations. Finally, significant reductions in transconjugants for plasmids of each incompatibility type (IncP1ε, IncFIβ, and IncI1) tested were detected. This study demonstrates for the first time the broad inhibition ability of SCFAs on bacterial plasmid transfer and eliminates AMR with minimal effect on bacteria. Implementing interventions that increase the concentrations of SCFAs in the gut may be a viable method to reduce the risk, incidence, and rate of AMR emergence in agricultural and human environments.
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Affiliation(s)
- Logan C. Ott
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
| | - Melha Mellata
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
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3
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Gong Z, Qu Z, Cai J. Gene cloning, expression, and enzyme kinetics analysis of Eimeria tenella 2- methylcitrate synthase. Vet Parasitol 2024; 328:110193. [PMID: 38704976 DOI: 10.1016/j.vetpar.2024.110193] [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: 01/16/2024] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/07/2024]
Abstract
In prokaryotes and lower eukaryotes, 2-methylcitrate cycle (2-MCC) is the main pathway for propionate decomposition and transformation, but little is known about the 2-MCC pathway of Eimeria tenella. The analysis of genomic data found that the coding gene of 2- methylcitrate synthase (EC 2.3.3.5, PrpC) exists in E. tenella, which is a key enzyme of 2-MCC pathway. Through the search analysis of the database (ToxoDB), it was found that ETH_ 00026655 contains the complete putative sequence of EtprpC. In this study, we amplified the ORF sequence of EtprpC based on putative sequence. Then, prokaryotic expression, enzyme activity and kinetic analysis was performed. The results showed that the EtprpC ORF sequence was 1272 bp, encoding a 46.3 kDa protein comprising 424 amino acids. Enzyme activity assays demonstrate linearity between the initial reaction rate (OD/min) and EtPrpC concentration (ranging from 1.5 to 9 µg/reaction), with optimal enzyme activity observed at 41°C and pH 8.0. The results of enzymatic kinetic analysis showed that the Km of EtPrpC for propionyl-CoA, oxaloacetic acid, and acetyl-CoA was 5.239 ± 0.17 mM, 1.102 ± 0.08 μM, and 5.999 ± 1.24 μM, respectively. The Vmax was 191.11 ± 19.1 nmol/min/mg, 225.48 ± 14.4 nmol/min/mg, and 370.02 ± 25.8 nmol/min/mg when EtPrpC concentration at 4, 6, and 8 μg, respectively. Although the ability of EtPrpC to catalyze acetyl-CoA is only 0.11% of its ability to catalyze propionyl-CoA, it indicates that the 2-MCC pathway in E. tenella is similar to that in bacteria and may have a bypass function in the TCA cycle. This study can provide the theoretical foundation for the new drug targets and the development of new anticoccidial drugs.
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Affiliation(s)
- Zhenxing Gong
- College of Animal Science and Technology, Ningxia University, Yinchuan, Ningxia Province 750021, People's Republic of China; State Key Laboratory of Veterinary Etiological Biology, Lanzhou, Gansu Province 730046, People's Republic of China; Key Laboratory of Veterinary Parasitology of Gansu Province, 730046, People's Republic of China; Innovation of Research Program of Gastrointestinal Infection and Mucosal Immunity of Poultry and Pig, 730046, People's Republic of China; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China.
| | - Zigang Qu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou, Gansu Province 730046, People's Republic of China; Key Laboratory of Veterinary Parasitology of Gansu Province, 730046, People's Republic of China; Innovation of Research Program of Gastrointestinal Infection and Mucosal Immunity of Poultry and Pig, 730046, People's Republic of China; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China.
| | - Jianping Cai
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou, Gansu Province 730046, People's Republic of China; Key Laboratory of Veterinary Parasitology of Gansu Province, 730046, People's Republic of China; Innovation of Research Program of Gastrointestinal Infection and Mucosal Immunity of Poultry and Pig, 730046, People's Republic of China; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China.
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4
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Santos-Oliveira PH, Silva JGP, Blank LM, Silva LF, Gomez JGC. Constant fed-batch cultivation with glucose and propionate as co-substrate: A strategy to fine-tune polyhydroxyalkanoates monomeric composition in Pseudomonas spp. Int J Biol Macromol 2024; 256:128287. [PMID: 37995793 DOI: 10.1016/j.ijbiomac.2023.128287] [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: 05/12/2023] [Revised: 11/14/2023] [Accepted: 11/18/2023] [Indexed: 11/25/2023]
Abstract
Pseudomonas sp. LFM693 is a 2-methylisocitrate lyase (prpB) disrupted mutant. This enzyme catalyzes a step in the 2-methylcitrate cycle, the only known and described pathway for propionate oxidation in this organism. The affected mutants can efficiently produce PHA containing even and odd-chain length hydroxyalkanoates (HAeven/odd) in the presence of propionate and glucose. In this study, a constant fed-batch configuration was utilized to control the composition of PHA and decrease the toxicity of propionate. The incorporation of HAodd into the copolymer was linear, ranging from 7 to approximately 30 %, and correlated directly with the propionate/glucose molar ratio in the feeding solution. This allowed for the molecular composition of the mclPHA to be fine-tuned with minimum process monitoring and control. The average PHA content was 52 % cell dry weight with a molar composition that favored 3-hydroxyalkanoates containing C8, C9, and C10. The conversion factor of propionate to HAodd varied between 0.36 and 0.53 mol·mol-1 (YHAodd/prop.), which are significantly lower than the theoretical maximum efficiency (1.0 mol·mol-1). These results along with the lack of 2-methylisocitrate as a byproduct provides further support for the evidence that the mutant prpB- is still capable of oxidizing propionate.
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Affiliation(s)
- Pedro Henrique Santos-Oliveira
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | | | - Lars Mathias Blank
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Luiziana Ferreira Silva
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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5
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Vinacour M, Moiana M, Forné I, Jung K, Bertea M, Calero Valdayo PM, Nikel PI, Imhof A, Palumbo MC, Fernández Do Porto D, Ruiz JA. Genetic dissection of the degradation pathways for the mycotoxin fusaric acid in Burkholderia ambifaria T16. Appl Environ Microbiol 2023; 89:e0063023. [PMID: 38054732 PMCID: PMC10734416 DOI: 10.1128/aem.00630-23] [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: 04/20/2023] [Accepted: 10/25/2023] [Indexed: 12/07/2023] Open
Abstract
IMPORTANCE Fusaric acid (FA) is an important virulence factor produced by several Fusarium species. These fungi are responsible for wilt and rot diseases in a diverse range of crops. FA is toxic for animals, humans and soil-borne microorganisms. This mycotoxin reduces the survival and competition abilities of bacterial species able to antagonize Fusarium spp., due to its negative effects on viability and the production of antibiotics effective against these fungi. FA biodegradation is not a common characteristic among bacteria, and the determinants of FA catabolism have not been identified so far in any microorganism. In this study, we identified genes, enzymes, and metabolic pathways involved in the degradation of FA in the soil bacterium Burkholderia ambifaria T16. Our results provide insights into the catabolism of a pyridine-derivative involved in plant pathogenesis by a rhizosphere bacterium.
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Affiliation(s)
- Matias Vinacour
- Instituto de Investigaciones en Biociencias Agrícolas y Ambientales (INBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mauro Moiana
- Instituto de Investigaciones en Biociencias Agrícolas y Ambientales (INBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ignasi Forné
- Protein Analysis Unit, BioMedical Center (BMC), Ludwig-Maximilians-Universität München, Martinsried, Germany
| | - Kirsten Jung
- Faculty Biology, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
| | - Micaela Bertea
- Instituto de Investigaciones en Biociencias Agrícolas y Ambientales (INBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Patricia M. Calero Valdayo
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Pablo I. Nikel
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Axel Imhof
- Protein Analysis Unit, BioMedical Center (BMC), Ludwig-Maximilians-Universität München, Martinsried, Germany
| | - Miranda C. Palumbo
- Instituto de Cálculo (IC), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Dario Fernández Do Porto
- Instituto de Cálculo (IC), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Jimena A. Ruiz
- Instituto de Investigaciones en Biociencias Agrícolas y Ambientales (INBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
- Faculty Biology, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
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6
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Cruz-Leite VRM, Moreira ALE, Silva LOS, Inácio MM, Parente-Rocha JA, Ruiz OH, Weber SS, Soares CMDA, Borges CL. Proteomics of Paracoccidioides lutzii: Overview of Changes Triggered by Nitrogen Catabolite Repression. J Fungi (Basel) 2023; 9:1102. [PMID: 37998907 PMCID: PMC10672198 DOI: 10.3390/jof9111102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/06/2023] [Accepted: 11/08/2023] [Indexed: 11/25/2023] Open
Abstract
Members of the Paracoccidioides complex are the causative agents of Paracoccidioidomycosis (PCM), a human systemic mycosis endemic in Latin America. Upon initial contact with the host, the pathogen needs to uptake micronutrients. Nitrogen is an essential source for biosynthetic pathways. Adaptation to nutritional stress is a key feature of fungi in host tissues. Fungi utilize nitrogen sources through Nitrogen Catabolite Repression (NCR). NCR ensures the scavenging, uptake and catabolism of alternative nitrogen sources, when preferential ones, such as glutamine or ammonium, are unavailable. The NanoUPLC-MSE proteomic approach was used to investigate the NCR response of Paracoccidioides lutzii after growth on proline or glutamine as a nitrogen source. A total of 338 differentially expressed proteins were identified. P. lutzii demonstrated that gluconeogenesis, β-oxidation, glyoxylate cycle, adhesin-like proteins, stress response and cell wall remodeling were triggered in NCR-proline conditions. In addition, within macrophages, yeast cells trained under NCR-proline conditions showed an increased ability to survive. In general, this study allows a comprehensive understanding of the NCR response employed by the fungus to overcome nutritional starvation, which in the human host is represented by nutritional immunity. In turn, the pathogen requires rapid adaptation to the changing microenvironment induced by macrophages to achieve successful infection.
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Affiliation(s)
- Vanessa Rafaela Milhomem Cruz-Leite
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
| | - André Luís Elias Moreira
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
| | - Lana O’Hara Souza Silva
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
| | - Moises Morais Inácio
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
- Estácio de Goiás University Center—FESGO, Goiânia 74063-010, GO, Brazil
| | - Juliana Alves Parente-Rocha
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
| | - Orville Hernandez Ruiz
- MICROBA Research Group, Cellular and Molecular Biology Unit, Department of Microbiology, School of Microbiology, University of Antioquia, Medellín 050010, Colombia;
| | - Simone Schneider Weber
- Faculty of Pharmaceutical Sciences, Food and Nutrition, Federal University of Mato Grosso do Sul, Campo Grande 79304-902, MS, Brazil;
| | - Célia Maria de Almeida Soares
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
| | - Clayton Luiz Borges
- Department of Biochemistry and Molecular Biology, Institute of Biological Sciences II, Federal University of Goiás, Goiânia 74690-900, GO, Brazil; (A.L.E.M.); (L.O.S.S.); (M.M.I.); (J.A.P.-R.); (C.M.d.A.S.)
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7
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Huang Z, Wang Q, Khan IA, Li Y, Wang J, Wang J, Liu X, Lin F, Lu J. The Methylcitrate Cycle and Its Crosstalk with the Glyoxylate Cycle and Tricarboxylic Acid Cycle in Pathogenic Fungi. Molecules 2023; 28:6667. [PMID: 37764443 PMCID: PMC10534831 DOI: 10.3390/molecules28186667] [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: 08/01/2023] [Revised: 09/06/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
In fungi, the methylcitrate cycle converts cytotoxic propionyl-coenzyme A (CoA) to pyruvate, which enters gluconeogenesis. The glyoxylate cycle converts acetyl-CoA to succinate, which enters gluconeogenesis. The tricarboxylic acid cycle is a central carbon metabolic pathway that connects the methylcitrate cycle, the glyoxylate cycle, and other metabolisms for lipids, carbohydrates, and amino acids. Fungal citrate synthase and 2-methylcitrate synthase as well as isocitrate lyase and 2-methylisocitrate lyase, each evolved from a common ancestral protein. Impairment of the methylcitrate cycle leads to the accumulation of toxic intermediates such as propionyl-CoA, 2-methylcitrate, and 2-methylisocitrate in fungal cells, which in turn inhibits the activity of many enzymes such as dehydrogenases and remodels cellular carbon metabolic processes. The methylcitrate cycle and the glyoxylate cycle synergistically regulate carbon source utilization as well as fungal growth, development, and pathogenic process in pathogenic fungi.
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Affiliation(s)
- Zhicheng Huang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; (Z.H.); (Q.W.); (Y.L.)
| | - Qing Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; (Z.H.); (Q.W.); (Y.L.)
| | - Irshad Ali Khan
- Department of Agriculture, The University of Swabi, Khyber 29380, Pakistan;
| | - Yan Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; (Z.H.); (Q.W.); (Y.L.)
| | - Jing Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (J.W.); (J.W.); (F.L.)
| | - Jiaoyu Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (J.W.); (J.W.); (F.L.)
| | - Xiaohong Liu
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China;
| | - Fucheng Lin
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (J.W.); (J.W.); (F.L.)
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China;
| | - Jianping Lu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; (Z.H.); (Q.W.); (Y.L.)
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8
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de Amorim MR, Barbosa CDS, Paz TA, Ióca LP, Nicácio KJ, de Oliveira LFP, Goulart MO, Paulino JM, da Cruz MO, Ferreira AG, Furlan M, de Lira SP, Dos Santos RA, Rodrigues A, Guido RVC, Berlinck RGS. Polyketide- and Terpenoid-Derived Metabolites Produced by a Marine-Derived Fungus, Peroneutypa sp. JOURNAL OF NATURAL PRODUCTS 2023; 86:1476-1486. [PMID: 37289832 DOI: 10.1021/acs.jnatprod.3c00175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Bioassay-guided investigation of the EtOAc-soluble extract of a culture of the marine-derived fungus Peroneutypa sp. M16 led to the isolation of seven new polyketide- and terpenoid-derived metabolites (1, 2, 4-8), along with known polyketides (3, 9-13). Structures of compounds 1, 2, and 4-8 were established by analysis of spectroscopic data. Absolute configurations of compounds 1, 2, 4, 6, 7, and 8 were determined by the comparison of experimental ECD spectra with calculated CD data. Compound 5 exhibited moderate antiplasmodial activity against both chloroquine-sensitive and -resistant strains of Plasmodium falciparum.
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Affiliation(s)
- Marcelo R de Amorim
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brazil
| | - Camila de S Barbosa
- Instituto de Física de São Carlos, Universidade de São Paulo, CEP 13563-120, São Carlos, SP, Brazil
| | - Tiago A Paz
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, CEP 14040-903, Ribeirão Preto, SP, Brazil
| | - Laura P Ióca
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brazil
| | - Karen J Nicácio
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brazil
| | - Lucianne F P de Oliveira
- Departamento de Ciências Exatas, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, CEP 13418-900, Piracicaba, SP, Brazil
| | - Mirian O Goulart
- Centro de Pesquisa em Ciência e Tecnologia, Universidade de Franca, CEP 14404-600, Franca, SP, Brazil
| | - Julia M Paulino
- Centro de Pesquisa em Ciência e Tecnologia, Universidade de Franca, CEP 14404-600, Franca, SP, Brazil
| | - Mateus O da Cruz
- Departamento de Biologia Geral e Aplicada, Universidade Estadual Paulista "Júlio de Mesquita Filho", CEP 13506-900, Rio Claro, SP, Brazil
| | - Antonio G Ferreira
- Departamento de Química, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil
| | - Maysa Furlan
- Instituto de Química de Araraquara, Universidade Estadual Paulista "Júlio de Mesquita Filho", CEP 14800-900, Araraquara, SP, Brazil
| | - Simone P de Lira
- Departamento de Ciências Exatas, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, CEP 13418-900, Piracicaba, SP, Brazil
| | - Raquel A Dos Santos
- Centro de Pesquisa em Ciência e Tecnologia, Universidade de Franca, CEP 14404-600, Franca, SP, Brazil
| | - André Rodrigues
- Departamento de Biologia Geral e Aplicada, Universidade Estadual Paulista "Júlio de Mesquita Filho", CEP 13506-900, Rio Claro, SP, Brazil
| | - Rafael V C Guido
- Instituto de Física de São Carlos, Universidade de São Paulo, CEP 13563-120, São Carlos, SP, Brazil
| | - Roberto G S Berlinck
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brazil
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9
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Zhu C, Tang Y, Ren D, Ren W, Xue Y, Suthaparan A, Li J, Wang Y, Xu L, Zhu P. Propionate poses antivirulence activity against Botrytis cinerea via regulating its metabolism, infection cushion development and overall pathogenic factors. Food Chem 2023; 410:135443. [PMID: 36680882 DOI: 10.1016/j.foodchem.2023.135443] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 12/10/2022] [Accepted: 01/07/2023] [Indexed: 01/15/2023]
Abstract
Botrytis cinerea is a devastating pathogen causing gray mold in fruits and vegetables if not properly managed. Although the mechanisms remain unclear, we previously revealed that the safe food additive calcium propionate (CP) could suppress gray mold development on grapes. The present study reports that sub-lethal dose of CP (0.2 % w/v) could allow growth with substantial reprograming the genome-wide transcripts of B. cinerea. Upon CP treatment, the genes related to fungal methylcitrate cycle (responsible for catabolizing propionate) were upregulated. Meanwhile, CP treatment broadly downregulated the transcript levels of the virulence factors. Further comparative analysis of multiple transcriptomes confirmed that the CP treatment largely suppressed the expression of genes related to development and function of infection cushion. Collectively, these findings indicate that CP can not only reduce fungal growth, but also abrogate fungal virulence factors. Thus, CP has significant potential for the control of gray mold in fruit crops.
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Affiliation(s)
- Chuanxi Zhu
- School of Life Sciences, East China Normal University, 200241 Shanghai, China
| | - Yan Tang
- School of Life Sciences, East China Normal University, 200241 Shanghai, China
| | - Dandan Ren
- School of Life Sciences, East China Normal University, 200241 Shanghai, China
| | - Weiheng Ren
- School of Life Sciences, East China Normal University, 200241 Shanghai, China
| | - Yongjun Xue
- School of Life Sciences, East China Normal University, 200241 Shanghai, China
| | - Aruppillai Suthaparan
- Department of Plant Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, 1432 Ås, Norway
| | - Jufen Li
- Horticultural Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Protected Horticultural Technology, 201106 Shanghai, China
| | - Yiwen Wang
- School of Life Sciences, East China Normal University, 200241 Shanghai, China
| | - Ling Xu
- School of Life Sciences, East China Normal University, 200241 Shanghai, China.
| | - Pinkuan Zhu
- School of Life Sciences, East China Normal University, 200241 Shanghai, China.
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10
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New Methylcitrate Synthase Inhibitor Induces Proteolysis, Lipid Degradation and Pyruvate Excretion in Paracoccidioides brasiliensis. J Fungi (Basel) 2023; 9:jof9010108. [PMID: 36675929 PMCID: PMC9865517 DOI: 10.3390/jof9010108] [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: 12/20/2022] [Revised: 01/08/2023] [Accepted: 01/11/2023] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Paracoccidioidomycosis is a systemic mycosis caused by the inhalation of conidia of the genus Paracoccidioides. During the infectious process, fungal cells use several carbon sources, leading to the production of propionyl-CoA. The latter is metabolized by the methylcitrate synthase, a key enzyme of the methylcitrate cycle. We identified an inhibitor compound (ZINC08964784) that showed antifungal activity against P. brasiliensis. METHODS This work aimed to understand the fungal metabolic response of P. brasiliensis cells exposed to ZINC08964784 through a proteomics approach. We used a glucose-free medium supplemented with propionate in order to simulate the environment found by the pathogen during the infection. We performed pyruvate dosage, proteolytic assay, dosage of intracellular lipids and quantification of reactive oxygen species in order to validate the proteomic results. RESULTS The proteomic analysis indicated that the fungal cells undergo a metabolic shift due to the inhibition of the methylcitrate cycle and the generation of reactive species. Proteolytic enzymes were induced, driving amino acids into degradation for energy production. In addition, glycolysis and the citric acid cycle were down-regulated while ß-oxidation was up-regulated. The accumulation of pyruvate and propionyl-CoA led the cells to a state of oxidative stress in the presence of ZINC08964784. CONCLUSIONS The inhibition of methylcitrate synthase caused by the compound promoted a metabolic shift in P. brasiliensis damaging energy production and generating oxidative stress. Hence, the compound is a promising alternative for developing new strategies of therapies against paracoccidioidomycosis.
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11
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Chen X, Zhang D, Li Y, Li H, Lou J, Li X, Wei M. Changes in rhizospheric microbiome structure and soil metabolic function in response to continuous cucumber cultivation. FEMS Microbiol Ecol 2022; 98:6807410. [PMID: 36341539 DOI: 10.1093/femsec/fiac129] [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: 06/29/2022] [Revised: 09/26/2022] [Accepted: 11/03/2022] [Indexed: 11/09/2022] Open
Abstract
With the increasing reliance on intensive arable agriculture, analysis of the problems associated with continuous cropping has become a global research focus. Here, high-throughput sequencing and nontargeted metabolomics were used to evaluate the responses of soil microbial community structure and soil metabolic function to continuous cucumber cultivation (from 1 to 18 years of continuous cultivation) in greenhouses. Continuous cucumber cropping resulted in increased soil nutrient concentrations, but decreased concentrations of available nutrients. The abundance of several bacterial genera associated with nutrient cycling, such as Bacillus and Sphingomonas, was reduced by continuous cucumber cultivation. The abundance of several beneficial fungal genera, including pathogen antagonists (e.g. Chaetomium, Mortierella, Aspergillus, and Penicillium), were found to gradually decrease in response to the increased duration of continuous cropping. 3-amino-2-naphthoic acid and L-valine increased initially and then decreased as the cropping continued, which were related to fatty acid metabolism and amino acid biosynthesis. We also confirmed a close association between microbial community structure and soil metabolites. This study linked the changes in microbial community structure and metabolites in the rhizosphere soil and provided new insights into soil-microbial interactions in continuous cucumber culture systems.
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Affiliation(s)
- Xiaolu Chen
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China
| | - Dalong Zhang
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China.,Scientific Observing and Experimental Starion of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture and Rural Affairs, 271018 Tai'an, China
| | - Yiman Li
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China
| | - Hengyu Li
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China
| | - Jie Lou
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China
| | - Xiaotian Li
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China
| | - Min Wei
- State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, 271018 Tai'an, China.,Scientific Observing and Experimental Starion of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture and Rural Affairs, 271018 Tai'an, China
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12
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Wirth NT, Gurdo N, Krink N, Vidal-Verdú À, Donati S, Férnandez-Cabezón L, Wulff T, Nikel PI. A synthetic C2 auxotroph of Pseudomonas putida for evolutionary engineering of alternative sugar catabolic routes. Metab Eng 2022; 74:83-97. [PMID: 36155822 DOI: 10.1016/j.ymben.2022.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/17/2022] [Accepted: 09/17/2022] [Indexed: 11/30/2022]
Abstract
Acetyl-coenzyme A (AcCoA) is a metabolic hub in virtually all living cells, serving as both a key precursor of essential biomass components and a metabolic sink for catabolic pathways for a large variety of substrates. Owing to this dual role, tight growth-production coupling schemes can be implemented around the AcCoA node. Building on this concept, a synthetic C2 auxotrophy was implemented in the platform bacterium Pseudomonas putida through an in silico-informed engineering approach. A growth-coupling strategy, driven by AcCoA demand, allowed for direct selection of an alternative sugar assimilation route-the phosphoketolase (PKT) shunt from bifidobacteria. Adaptive laboratory evolution forced the synthetic P. putida auxotroph to rewire its metabolic network to restore C2 prototrophy via the PKT shunt. Large-scale structural chromosome rearrangements were identified as possible mechanisms for adjusting the network-wide proteome profile, resulting in improved PKT-dependent growth phenotypes. 13C-based metabolic flux analysis revealed an even split between the native Entner-Doudoroff pathway and the synthetic PKT bypass for glucose processing, leading to enhanced carbon conservation. These results demonstrate that the P. putida metabolism can be radically rewired to incorporate a synthetic C2 metabolism, creating novel network connectivities and highlighting the importance of unconventional engineering strategies to support efficient microbial production.
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Affiliation(s)
- Nicolas T Wirth
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark
| | - Nicolás Gurdo
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark
| | - Nicolas Krink
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark
| | - Àngela Vidal-Verdú
- Institute for Integrative Systems Biology I2SysBio (Universitat de València-CSIC), Calle del Catedràtic Agustin Escardino Benlloch 9, 46980, Paterna, Spain
| | - Stefano Donati
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark
| | - Lorena Férnandez-Cabezón
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark
| | - Tune Wulff
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark
| | - Pablo I Nikel
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 220 2800, Kongens Lyngby, Denmark.
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13
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Feng J, Hauser M, Cox RJ, Skellam E. Engineering Aspergillus oryzae for the Heterologous Expression of a Bacterial Modular Polyketide Synthase. J Fungi (Basel) 2021; 7:1085. [PMID: 34947068 PMCID: PMC8708903 DOI: 10.3390/jof7121085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 12/31/2022] Open
Abstract
Microbial natural products have had phenomenal success in drug discovery and development yet form distinct classes based on the origin of their native producer. Methods that enable metabolic engineers to combine the most useful features of the different classes of natural products may lead to molecules with enhanced biological activities. In this study, we modified the metabolism of the fungus Aspergillus oryzae to enable the synthesis of triketide lactone (TKL), the product of the modular polyketide synthase DEBS1-TE engineered from bacteria. We established (2S)-methylmalonyl-CoA biosynthesis via introducing a propionyl-CoA carboxylase complex (PCC); reassembled the 11.2 kb DEBS1-TE coding region from synthetic codon-optimized gene fragments using yeast recombination; introduced bacterial phosphopantetheinyltransferase SePptII; investigated propionyl-CoA synthesis and degradation pathways; and developed improved delivery of exogenous propionate. Depending on the conditions used titers of TKL ranged from <0.01-7.4 mg/L. In conclusion, we have demonstrated that A. oryzae can be used as an alternative host for the synthesis of polyketides from bacteria, even those that require toxic or non-native substrates. Our metabolically engineered A. oryzae may offer advantages over current heterologous platforms for producing valuable and complex natural products.
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Affiliation(s)
- Jin Feng
- Institute for Organic Chemistry and Biomolekular Wirkstoff Zentrum, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany; (J.F.); (M.H.)
| | - Maurice Hauser
- Institute for Organic Chemistry and Biomolekular Wirkstoff Zentrum, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany; (J.F.); (M.H.)
| | - Russell J. Cox
- Institute for Organic Chemistry and Biomolekular Wirkstoff Zentrum, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany; (J.F.); (M.H.)
| | - Elizabeth Skellam
- Institute for Organic Chemistry and Biomolekular Wirkstoff Zentrum, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany; (J.F.); (M.H.)
- Department of Chemistry, BioDiscovery Institute, University of North Texas, 1155 Union Circle, Denton, TX 76201, USA
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14
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Oliveira LN, Lima PDS, Araújo DS, Portis IG, Santos Júnior ADCMD, Coelho ASG, de Sousa MV, Ricart CAO, Fontes W, Soares CMDA. iTRAQ-based proteomic analysis of Paracoccidioides brasiliensis in response to hypoxia. Microbiol Res 2021; 247:126730. [PMID: 33662850 DOI: 10.1016/j.micres.2021.126730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 01/29/2021] [Accepted: 02/13/2021] [Indexed: 02/06/2023]
Abstract
Aerobic organisms require oxygen for energy. In the course of the infection, adaptation to hypoxia is crucial for survival of human pathogenic fungi. Members of the Paracoccidioides complex face decreased oxygen tensions during the life cycle stages. In Paracoccidioides brasiliensis proteomic responses to hypoxia have not been investigated and the regulation of the adaptive process is still unknown, and this approach allowed the identification of 216 differentially expressed proteins in hypoxia using iTRAQ-labelling. Data suggest that P. brasiliensis reprograms its metabolism when submitted to hypoxia. The fungus reduces its basal metabolism and general transport proteins. Energy and general metabolism were more representative and up regulated. Glucose is apparently directed towards glycolysis or the production of cell wall polymers. Plasma membrane/cell wall are modulated by increasing ergosterol and glucan, respectively. In addition, molecules such as ethanol and acetate are produced by this fungus indicating that alternative carbon sources probably are activated to obtain energy. Also, detoxification mechanisms are activated. The results were compared with label free proteomics data from Paracoccidioides lutzii. Biochemical pathways involved with acetyl-CoA, pyruvate and ergosterol synthesis were up-regulated in both fungi. On the other hand, proteins from TCA, transcription, protein fate/degradation, cellular transport, signal transduction and cell defense/virulence processes presented different profiles between species. Particularly, proteins related to methylcitrate cycle and those involved with acetate and ethanol synthesis were increased in P. brasiliensis proteome, whereas GABA shunt were accumulated only in P. lutzii. The results emphasize metabolic adaptation processes for distinct Paracoccidioides species.
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Affiliation(s)
- Lucas Nojosa Oliveira
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, 74001-970, Goiânia, Goiás, Brazil.
| | - Patrícia de Sousa Lima
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, 74001-970, Goiânia, Goiás, Brazil.
| | - Danielle Silva Araújo
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, 74001-970, Goiânia, Goiás, Brazil.
| | - Igor Godinho Portis
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, 74001-970, Goiânia, Goiás, Brazil.
| | | | | | - Marcelo Valle de Sousa
- Departmento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Campus Darcy Ribeiro, Asa Norte, 70910-900, Brasília, DF, Brazil.
| | - Carlos André Ornelas Ricart
- Departmento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Campus Darcy Ribeiro, Asa Norte, 70910-900, Brasília, DF, Brazil.
| | - Wagner Fontes
- Departmento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Campus Darcy Ribeiro, Asa Norte, 70910-900, Brasília, DF, Brazil.
| | - Célia Maria de Almeida Soares
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, 74001-970, Goiânia, Goiás, Brazil.
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15
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Feng J, He L, Xiao X, Chen Z, Chen C, Chu J, Lu S, Li X, Mylonakis E, Xi L. Methylcitrate cycle gene MCD is essential for the virulence of Talaromyces marneffei. Med Mycol 2020; 58:351-361. [PMID: 31290549 DOI: 10.1093/mmy/myz063] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 04/23/2019] [Accepted: 07/03/2019] [Indexed: 01/11/2023] Open
Abstract
Talaromyces marneffei (T. marneffei), which used to be known as Penicillium marneffei, is the causative agent of the fatal systemic mycosis known as talaromycosis. For the purpose of understanding the role of methylcitrate cycle in the virulence of T. marneffei, we generated MCD deletion (ΔMCD) and complementation (ΔMCD+) mutants of T. marneffei. Growth in different carbon sources showed that ΔMCD cannot grow on propionate media and grew slowly on the valerate, valine, methionine, isoleucine, cholesterol, and YNB (carbon free) media. The macrophage killing assay showed that ΔMCD was attenuated in macrophages of mice in vitro, especially at the presence of propionate. Finally, virulence studies in a murine infection experiment revealed attenuated virulence of the ΔMCD, which indicates MCD is essential for T. marneffei virulence in the host. This experiment laid the foundation for the further study of the specific mechanisms underlying the methylcitrate cycle of T. marneffei and may provide suitable targets for new antifungals.
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Affiliation(s)
- Jiao Feng
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Dermatology Hospital of Southern Medical University, Guangzhou, China
| | - Liya He
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xing Xiao
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhiwen Chen
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Chunmei Chen
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jieming Chu
- Johns Hopkins University Bloomberg School of Public Health, Wolfe Street, Baltimore, MD, USA
| | - Sha Lu
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiqing Li
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Eleftherios Mylonakis
- Division of Infectious Diseases, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Liyan Xi
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Dermatology Hospital of Southern Medical University, Guangzhou, China
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16
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Zheng L, Yang Y, Wang H, Fan A, Zhang L, Li SM. Ustethylin Biosynthesis Implies Phenethyl Derivative Formation in Aspergillus ustus. Org Lett 2020; 22:7837-7841. [DOI: 10.1021/acs.orglett.0c02719] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Liujuan Zheng
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch Straße 4, 35037 Marburg, Germany
| | - Yiling Yang
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch Straße 4, 35037 Marburg, Germany
| | - Haowen Wang
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch Straße 4, 35037 Marburg, Germany
| | - Aili Fan
- College of Life Science and Technology, Beijing University of Chemical Technology, North Third Ring Road 15, Chaoyang District, 100029 Beijing, China
| | - Liping Zhang
- Key Laboratory of Tropical Marine Bio-resources, South China Sea Institute of Oceanology Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
| | - Shu-Ming Li
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch Straße 4, 35037 Marburg, Germany
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17
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Santos LPA, Assunção LDP, Lima PDS, Tristão GB, Brock M, Borges CL, Silva-Bailão MG, Soares CMDA, Bailão AM. Propionate metabolism in a human pathogenic fungus: proteomic and biochemical analyses. IMA Fungus 2020; 11:9. [PMID: 32617258 PMCID: PMC7324963 DOI: 10.1186/s43008-020-00029-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 03/11/2020] [Indexed: 01/06/2023] Open
Abstract
Fungi of the complex Paracoccidioides spp. are thermodimorphic organisms that cause Paracoccidioidomycosis, one of the most prevalent mycoses in Latin America. These fungi present metabolic mechanisms that contribute to the fungal survival in host tissues. Paracoccidioides lutzii activates glycolysis and fermentation while inactivates aerobic metabolism in iron deprivation, a condition found during infection. In lungs Paracoccidioides brasiliensis face a glucose poor environment and relies on the beta-oxidation to support energy requirement. During mycelium to yeast transition P. lutzii cells up-regulate transcripts related to lipid metabolism and cell wall remodeling in order to cope with the host body temperature. Paracoccidioides spp. cells also induce transcripts/enzymes of the methylcitrate cycle (MCC), a pathway responsible for propionyl-CoA metabolism. Propionyl-CoA is a toxic compound formed during the degradation of odd-chain fatty acids, branched chain amino acids and cholesterol. Therefore, fungi require a functional MCC for full virulence and the ability to metabolize propionyl-CoA is related to the virulence traits in Paracoccidioides spp. On this way we sought to characterize the propionate metabolism in Paracoccidioides spp. The data collected showed that P. lutzii grows in propionate and activates the MCC by accumulating transcripts and proteins of methylcitrate synthase (MCS), methylcitrate dehydratase (MCD) and methylisocitrate lyase (MCL). Biochemical characterization of MCS showed that the enzyme is regulated by phosphorylation, an event not yet described. Proteomic analyses further indicate that P. lutzii yeast cells degrades lipids and amino acids to support the carbon requirement for propionate metabolism. The induction of a putative propionate kinase suggests that fungal cells use propionyl-phosphate as an intermediate in the production of toxic propionyl-CoA. Concluding, the metabolism of propionate in P. lutzii is under regulation at transcriptional and phosphorylation levels and that survival on this carbon source requires additional mechanisms other than activation of MCC.
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Affiliation(s)
- Luiz Paulo Araújo Santos
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Leandro do Prado Assunção
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Patrícia de Souza Lima
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
- Universidade Estadual de Goiás, Itapuranga, Brazil
| | - Gabriel Brum Tristão
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Matthias Brock
- Fungal Biology and Genetics Group, University of Nottingham, Nottingham, UK
| | - Clayton Luiz Borges
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Mirelle Garcia Silva-Bailão
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | | | - Alexandre Melo Bailão
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
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18
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Zheng C, Yu Z, Du C, Gong Y, Yin W, Li X, Li Z, Römling U, Chou SH, He J. 2-Methylcitrate cycle: a well-regulated controller of Bacillus sporulation. Environ Microbiol 2019; 22:1125-1140. [PMID: 31858668 DOI: 10.1111/1462-2920.14901] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/26/2019] [Accepted: 12/16/2019] [Indexed: 12/23/2022]
Abstract
Bacillus thuringiensis is the most widely used eco-friendly biopesticide, containing two primary determinants of biocontrol, endospore and insecticidal crystal proteins (ICPs). The 2-methylcitrate cycle is a widespread carbon metabolic pathway playing a crucial role in channelling propionyl-CoA, but with poorly understood metabolic regulatory mechanisms. Here, we dissect the transcriptional regulation of the 2-methylcitrate cycle operon prpCDB and report its unprecedented role in controlling the sporulation process of B. thuringiensis. We found that the transcriptional activity of the prp operon encoding the three critical enzymes PrpC, PrpD, and PrpB in the 2-methylcitrate cycle was negatively regulated by the two global transcription factors CcpA and AbrB, while positively regulated by the LysR family regulator CcpC, which jointly account for the fact that the 2-methylcitrate cycle is specifically and highly active in the stationary phase of growth. We also found that the prpD mutant accumulated 2-methylcitrate, the intermediate metabolite of the 2-methylcitrate cycle, which delayed and inhibited sporulation at the early stage. Thus, our results not only revealed sophisticated transcriptional regulatory mechanisms for the metabolic 2-methylcitrate cycle but also identified 2-methylcitrate as a novel regulator of sporulation in B. thuringiensis.
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Affiliation(s)
- Cao Zheng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China.,Hubei Province Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hubei Key Laboratory of Quality Control of Characteristic Fruits and Vegetables, College of Life Science and Technology, Hubei Engineering University, Xiaogan, Hubei, 432000, People's Republic of China
| | - Zhaoqing Yu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Cuiying Du
- Hubei Province Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hubei Key Laboratory of Quality Control of Characteristic Fruits and Vegetables, College of Life Science and Technology, Hubei Engineering University, Xiaogan, Hubei, 432000, People's Republic of China
| | - Yujing Gong
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Wen Yin
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Xinfeng Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Zhou Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Shan-Ho Chou
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Jin He
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
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Schlachter CR, Klapper V, Radford T, Chruszcz M. Comparative studies of Aspergillus fumigatus 2-methylcitrate synthase and human citrate synthase. Biol Chem 2019; 400:1567-1581. [PMID: 31141475 DOI: 10.1515/hsz-2019-0106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 05/15/2019] [Indexed: 11/15/2022]
Abstract
Aspergillus fumigatus is a ubiquitous fungus that is not only a problem in agriculture, but also in healthcare. Aspergillus fumigatus drug resistance is becoming more prominent which is mainly attributed to the widespread use of fungicides in agriculture. The fungi-specific 2-methylcitrate cycle is responsible for detoxifying propionyl-CoA, a toxic metabolite produced as the fungus breaks down proteins and amino acids. The enzyme responsible for this detoxification is 2-methylcitrate synthase (mcsA) and is a potential candidate for the design of new anti-fungals. However, mcsA is very similar in structure to human citrate synthase (hCS) and catalyzes the same reaction. Therefore, both enzymes were studied in parallel to provide foundations for design of mcsA-specific inhibitors. The first crystal structures of citrate synthase from humans and 2-methylcitrate synthase from A. fumigatus are reported. The determined structures capture various conformational states of the enzymes and several inhibitors were identified and characterized. Despite a significant homology, mcsA and hCS display pronounced differences in substrate specificity and cooperativity. Considering that the active sites of the enzymes are almost identical, the differences in reactions catalyzed by enzymes are caused by residues that are in the vicinity of the active site and influence conformational changes of the enzymes.
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Affiliation(s)
- Caleb R Schlachter
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
| | - Vincent Klapper
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
| | - Taylor Radford
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA
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Yan Y, Wang H, Zhu S, Wang J, Liu X, Lin F, Lu J. The Methylcitrate Cycle is Required for Development and Virulence in the Rice Blast Fungus Pyricularia oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:1148-1161. [PMID: 30933666 DOI: 10.1094/mpmi-10-18-0292-r] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The methylcitrate cycle metabolizes propionyl-CoA, a toxic metabolite, into pyruvate. Pyricularia oryzae (syn. Magnaporthe oryzae) is a phytopathogenic fungus that causes a destructive blast disease in rice and wheat. We characterized the essential roles of the methylcitrate cycle in the development and virulence of P. oryzae using functional genomics. In P. oryzae, the transcript levels of MCS1 and MCL1, which encode a 2-methylcitrate synthase and a 2-methylisocitrate lyase, respectively, were upregulated during appressorium formation and when grown on propionyl-CoA-producing carbon sources. We found that deletion of MCS1 and MCL1 inhibited fungal growth on media containing both glucose and propionate, and media using propionate or propionyl-CoA-producing amino acids (valine, isoleucine, methionine, and threonine) as the sole carbon or nitrogen sources. The Δmcs1 mutant formed sparse aerial hyphae and did not produce conidia on complete medium (CM), while the Δmcl1 mutant showed decreased conidiation. The aerial mycelium of Δmcs1 displayed a lowered NAD+/NADH ratio, reduced nitric oxide content, and downregulated transcription of hydrophobin genes. Δmcl1 showed reduced appressorium turgor, severely delayed plant penetration, and weakened virulence. Addition of acetate recovered the growth of the wild type and Δmcs1 on medium containing both glucose and propionate and recovered the conidiation of both Δmcs1 and Δmcl1 on CM by reducing propionyl-CoA formation. Deletion of MCL1 together with ICL1, an isocitrate lyase gene in the glyoxylate cycle, greatly reduced the mutant's virulence as compared with the single-gene deletion mutants (Δicl1 and Δmcl1). This experimental evidence provides important information about the role of the methylcitrate cycle in development and virulence of P. oryzae by detoxification of propionyl-CoA and 2-methylisocitrate.
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Affiliation(s)
- Yuxin Yan
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
| | - Huan Wang
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
| | - Siyi Zhu
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
| | - Jing Wang
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
| | - Xiaohong Liu
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University
| | - Fucheng Lin
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University
| | - Jianping Lu
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
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The Nitrogen Regulator GlnR Directly Controls Transcription of the prpDBC Operon Involved in Methylcitrate Cycle in Mycobacterium smegmatis. J Bacteriol 2019; 201:JB.00099-19. [PMID: 30745367 DOI: 10.1128/jb.00099-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 02/03/2019] [Indexed: 12/13/2022] Open
Abstract
Mycobacterium tuberculosis utilizes fatty acids of the host as the carbon source. Metabolism of odd-chain fatty acids by Mycobacterium tuberculosis produces propionyl coenzyme A (propionyl-CoA). The methylcitrate cycle is essential for mycobacteria to utilize the propionyl-CoA to persist and grow on these fatty acids. In M. smegmatis, methylcitrate synthase, methylcitrate dehydratase, and methylisocitrate lyase involved in the methylcitrate cycle are encoded by prpC, prpD, and prpB, respectively, in operon prpDBC In this study, we found that the nitrogen regulator GlnR directly binds to the promoter region of the prpDBC operon and inhibits its transcription. The binding motif of GlnR was identified by bioinformatic analysis and validated using DNase I footprinting and electrophoretic mobility shift assays. The GlnR-binding motif is separated by a 164-bp sequence from the binding site of PrpR, a pathway-specific transcriptional activator of methylcitrate cycle, but the binding affinity of GlnR to prpDBC is much stronger than that of PrpR. Deletion of glnR resulted in faster growth in propionate or cholesterol medium compared with the wild-type strain. The ΔglnR mutant strain also showed a higher survival rate in macrophages. These results illustrated that the nitrogen regulator GlnR regulates the methylcitrate cycle through direct repression of the transcription of the prpDBC operon. This finding not only suggests an unprecedented link between nitrogen metabolism and the methylcitrate pathway but also reveals a potential target for controlling the growth of pathogenic mycobacteria.IMPORTANCE The success of mycobacteria survival in macrophage depends on its ability to assimilate fatty acids and cholesterol from the host. The cholesterol and fatty acids are catabolized via β-oxidation to generate propionyl coenzyme A (propionyl-CoA), which is then primarily metabolized via the methylcitrate cycle. Here, we found a typical GlnR binding box in the prp operon, and the affinity is much stronger than that of PrpR, a transcriptional activator of methylcitrate cycle. Furthermore, GlnR repressed the transcription of the prp operon. Deletion of glnR significantly enhanced the growth of Mycobacterium tuberculosis in propionate or cholesterol medium, as well as viability in macrophages. These findings provide new insights into the regulatory mechanisms underlying the cross talk of nitrogen and carbon metabolisms in mycobacteria.
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Reddick JJ, Sirkisoon S, Dahal RA, Hardesty G, Hage NE, Booth WT, Quattlebaum AL, Mills SN, Meadows VG, Adams SLH, Doyle JS, Kiel BE. First Biochemical Characterization of a Methylcitric Acid Cycle from Bacillus subtilis Strain 168. Biochemistry 2017; 56:5698-5711. [DOI: 10.1021/acs.biochem.7b00778] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jason J. Reddick
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Sherona Sirkisoon
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Rejwi Acharya Dahal
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Grant Hardesty
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Natalie E. Hage
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - William T. Booth
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Amy L. Quattlebaum
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Suzette N. Mills
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Victoria G. Meadows
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Sydney L. H. Adams
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Jennifer S. Doyle
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Brittany E. Kiel
- Department of Chemistry and
Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
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Casein phosphopeptides and CaCl2 increase penicillin production and cause an increment in microbody/peroxisome proteins in Penicillium chrysogenum. J Proteomics 2017; 156:52-62. [DOI: 10.1016/j.jprot.2016.12.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/15/2016] [Accepted: 12/31/2016] [Indexed: 12/11/2022]
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Abuhammad A. Cholesterol metabolism: a potential therapeutic target in Mycobacteria. Br J Pharmacol 2017; 174:2194-2208. [PMID: 28002883 DOI: 10.1111/bph.13694] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 11/06/2016] [Accepted: 12/16/2016] [Indexed: 12/14/2022] Open
Abstract
Tuberculosis (TB), although a curable disease, is still one of the most difficult infections to treat. Mycobacterium tuberculosis infects 10 million people worldwide and kills 1.5 million people each year. Reactivation of a latent infection is the major cause of TB. Cholesterol is a critical carbon source during latent infection. Catabolism of cholesterol contributes to the pool of propionyl-CoA, a precursor that is incorporated into lipid virulence factors. The M. tuberculosis genome contains a large regulon of cholesterol catabolic genes suggesting that the microorganism can utilize host sterol for infection and persistence. The protein products of these genes present ideal targets for rational drug discovery programmes. This review summarizes the development of enzyme inhibitors targeting the cholesterol pathway in M. tuberculosis. This knowledge is essential for the discovery of novel agents to treat M. tuberculosis infection. LINKED ARTICLES This article is part of a themed section on Drug Metabolism and Antibiotic Resistance in Micro-organisms. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.14/issuetoc.
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Homologues of xenobiotic metabolizing N-acetyltransferases in plant-associated fungi: Novel functions for an old enzyme family. Sci Rep 2015; 5:12900. [PMID: 26245863 PMCID: PMC4542470 DOI: 10.1038/srep12900] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 07/06/2015] [Indexed: 12/23/2022] Open
Abstract
Plant-pathogenic fungi and their hosts engage in chemical warfare, attacking each other with toxic products of secondary metabolism and defending themselves via an arsenal of xenobiotic metabolizing enzymes. One such enzyme is homologous to arylamine N-acetyltransferase (NAT) and has been identified in Fusarium infecting cereal plants as responsible for detoxification of host defence compound 2-benzoxazolinone. Here we investigate functional diversification of NAT enzymes in crop-compromising species of Fusarium and Aspergillus, identifying three groups of homologues: Isoenzymes of the first group are found in all species and catalyse reactions with acetyl-CoA or propionyl-CoA. The second group is restricted to the plant pathogens and is active with malonyl-CoA in Fusarium species infecting cereals. The third group generates minimal activity with acyl-CoA compounds that bind non-selectively to the proteins. We propose that fungal NAT isoenzymes may have evolved to perform diverse functions, potentially relevant to pathogen fitness, acetyl-CoA/propionyl-CoA intracellular balance and secondary metabolism.
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Gene Identification and Functional Analysis of Methylcitrate Synthase in Citric Acid-ProducingAspergillus nigerWU-2223L. Biosci Biotechnol Biochem 2014; 77:1492-8. [DOI: 10.1271/bbb.130139] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Otzen C, Bardl B, Jacobsen ID, Nett M, Brock M. Candida albicans utilizes a modified β-oxidation pathway for the degradation of toxic propionyl-CoA. J Biol Chem 2014; 289:8151-69. [PMID: 24497638 DOI: 10.1074/jbc.m113.517672] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Propionyl-CoA arises as a metabolic intermediate from the degradation of propionate, odd-chain fatty acids, and some amino acids. Thus, pathways for catabolism of this intermediate have evolved in all kingdoms of life, preventing the accumulation of toxic propionyl-CoA concentrations. Previous studies have shown that fungi generally use the methyl citrate cycle for propionyl-CoA degradation. Here, we show that this is not the case for the pathogenic fungus Candida albicans despite its ability to use propionate and valerate as carbon sources. Comparative proteome analyses suggested the presence of a modified β-oxidation pathway with the key intermediate 3-hydroxypropionate. Gene deletion analyses confirmed that the enoyl-CoA hydratase/dehydrogenase Fox2p, the putative 3-hydroxypropionyl-CoA hydrolase Ehd3p, the 3-hydroxypropionate dehydrogenase Hpd1p, and the putative malonate semialdehyde dehydrogenase Ald6p essentially contribute to propionyl-CoA degradation and its conversion to acetyl-CoA. The function of Hpd1p was further supported by the detection of accumulating 3-hydroxypropionate in the hpd1 mutant on propionyl-CoA-generating nutrients. Substrate specificity of Hpd1p was determined from recombinant purified enzyme, which revealed a preference for 3-hydroxypropionate, although serine and 3-hydroxyisobutyrate could also serve as substrates. Finally, virulence studies in a murine sepsis model revealed attenuated virulence of the hpd1 mutant, which indicates generation of propionyl-CoA from host-provided nutrients during infection.
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28
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Limenitakis J, Oppenheim RD, Creek DJ, Foth BJ, Barrett MP, Soldati-Favre D. The 2-methylcitrate cycle is implicated in the detoxification of propionate in Toxoplasma gondii. Mol Microbiol 2013; 87:894-908. [PMID: 23279335 PMCID: PMC3593168 DOI: 10.1111/mmi.12139] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2012] [Indexed: 12/22/2022]
Abstract
Toxoplasma gondii belongs to the coccidian subgroup of the Apicomplexa phylum. The Coccidia are obligate intracellular pathogens that establish infection in their mammalian host via the enteric route. These parasites lack a mitochondrial pyruvate dehydrogenase complex but have preserved the degradation of branched-chain amino acids (BCAA) as a possible pathway to generate acetyl-CoA. Importantly, degradation of leucine, isoleucine and valine could lead to concomitant accumulation of propionyl-CoA, a toxic metabolite that inhibits cell growth. Like fungi and bacteria, the Coccidia possess the complete set of enzymes necessary to metabolize and detoxify propionate by oxidation to pyruvate via the 2-methylcitrate cycle (2-MCC). Phylogenetic analysis provides evidence that the 2-MCC was acquired via horizontal gene transfer. In T. gondii tachyzoites, this pathway is split between the cytosol and the mitochondrion. Although the rate-limiting enzyme 2-methylisocitrate lyase is dispensable for parasite survival, its substrates accumulate in parasites deficient in the enzyme and its absence confers increased sensitivity to propionic acid. BCAA is also dispensable in tachyzoites, leaving unresolved the source of mitochondrial acetyl-CoA.
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Affiliation(s)
- Julien Limenitakis
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, CMU 1 Rue Michel Servet, 1211 Geneva, Switzerland
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Soanes DM, Chakrabarti A, Paszkiewicz KH, Dawe AL, Talbot NJ. Genome-wide transcriptional profiling of appressorium development by the rice blast fungus Magnaporthe oryzae. PLoS Pathog 2012; 8:e1002514. [PMID: 22346750 PMCID: PMC3276559 DOI: 10.1371/journal.ppat.1002514] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 12/16/2011] [Indexed: 11/19/2022] Open
Abstract
The rice blast fungus Magnaporthe oryzae is one of the most significant pathogens affecting global food security. To cause rice blast disease the fungus elaborates a specialised infection structure called an appressorium. Here, we report genome wide transcriptional profile analysis of appressorium development using next generation sequencing (NGS). We performed both RNA-Seq and High-Throughput SuperSAGE analysis to compare the utility of these procedures for identifying differential gene expression in M. oryzae. We then analysed global patterns of gene expression during appressorium development. We show evidence for large-scale gene expression changes, highlighting the role of autophagy, lipid metabolism and melanin biosynthesis in appressorium differentiation. We reveal the role of the Pmk1 MAP kinase as a key global regulator of appressorium-associated gene expression. We also provide evidence for differential expression of transporter-encoding gene families and specific high level expression of genes involved in quinate uptake and utilization, consistent with pathogen-mediated perturbation of host metabolism during plant infection. When considered together, these data provide a comprehensive high-resolution analysis of gene expression changes associated with cellular differentiation that will provide a key resource for understanding the biology of rice blast disease.
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Affiliation(s)
- Darren M. Soanes
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Apratim Chakrabarti
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Konrad H. Paszkiewicz
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Angus L. Dawe
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
- Department of Biology, New Mexico State University, Las Cruces, New Mexico, United States of America
| | - Nicholas J. Talbot
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
- * E-mail:
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Park JM, Kim TY, Lee SY. Genome-scale reconstruction and in silico analysis of the Ralstonia eutropha H16 for polyhydroxyalkanoate synthesis, lithoautotrophic growth, and 2-methyl citric acid production. BMC SYSTEMS BIOLOGY 2011; 5:101. [PMID: 21711532 PMCID: PMC3154180 DOI: 10.1186/1752-0509-5-101] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Accepted: 06/28/2011] [Indexed: 11/28/2022]
Abstract
Background Ralstonia eutropha H16, found in both soil and water, is a Gram-negative lithoautotrophic bacterium that can utillize CO2 and H2 as its sources of carbon and energy in the absence of organic substrates. R. eutropha H16 can reach high cell densities either under lithoautotrophic or heterotrophic conditions, which makes it suitable for a number of biotechnological applications. It is the best known and most promising producer of polyhydroxyalkanoates (PHAs) from various carbon substrates and is an environmentally important bacterium that can degrade aromatic compounds. In order to make R. eutropha H16 a more efficient and robust biofactory, system-wide metabolic engineering to improve its metabolic performance is essential. Thus, it is necessary to analyze its metabolic characteristics systematically and optimize the entire metabolic network at systems level. Results We present the lithoautotrophic genome-scale metabolic model of R. eutropha H16 based on the annotated genome with biochemical and physiological information. The stoichiometic model, RehMBEL1391, is composed of 1391 reactions including 229 transport reactions and 1171 metabolites. Constraints-based flux analyses were performed to refine and validate the genome-scale metabolic model under environmental and genetic perturbations. First, the lithoautotrophic growth characteristics of R. eutropha H16 were investigated under varying feeding ratios of gas mixture. Second, the genome-scale metabolic model was used to design the strategies for the production of poly[R-(-)-3hydroxybutyrate] (PHB) under different pH values and carbon/nitrogen source uptake ratios. It was also used to analyze the metabolic characteristics of R. eutropha when the phosphofructokinase gene was expressed. Finally, in silico gene knockout simulations were performed to identify targets for metabolic engineering essential for the production of 2-methylcitric acid in R. eutropha H16. Conclusion The genome-scale metabolic model, RehMBEL1391, successfully represented metabolic characteristics of R. eutropha H16 at systems level. The reconstructed genome-scale metabolic model can be employed as an useful tool for understanding its metabolic capabilities, predicting its physiological consequences in response to various environmental and genetic changes, and developing strategies for systems metabolic engineering to improve its metabolic performance.
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Affiliation(s)
- Jong Myoung Park
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Müller S, Fleck CB, Wilson D, Hummert C, Hube B, Brock M. Gene acquisition, duplication and metabolic specification: the evolution of fungal methylisocitrate lyases. Environ Microbiol 2011; 13:1534-48. [PMID: 21453403 DOI: 10.1111/j.1462-2920.2011.02458.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Gene duplication represents an evolutionary mechanism for expanding metabolic potential. Here we analysed the evolutionary relatedness of isocitrate and methylisocitrate lyases, which are key enzymes of the glyoxylate and methylcitrate cycle respectively. Phylogenetic analyses imply that ancient eukaryotes acquired an isocitrate lyase gene from a prokaryotic source, but it was lost in some eukaryotic lineages. However, protists, oomycetes and most fungi maintained this gene and successfully integrated the corresponding enzyme into the glyoxylate cycle. A second gene, encoding a highly related enzyme, is present in fungi, but absent from other eukaryotes. This methylisocitrate lyase is specifically involved in propionyl-CoA degradation via the methylcitrate cycle. Although bacteria possess methylisocitrate lyases with a structural fold similar to that of isocitrate lyases, their sequence identity to fungal methylisocitrate lyases is low. Phylogenetic analyses imply that fungal methylisocitrate lyases arose from gene duplication of an ancient isocitrate lyase gene from the basidiomycete lineage. Mutagenesis of active-site residues of a bacterial and fungal isocitrate lyase, which have been predicted to direct the substrate specificity of iso- and methylisocitrate lyases, experimentally confirmed the possibility of direct evolution of methylisocitrate lyases from isocitrate lyases. Thus, gene duplication has increased the metabolic capacity of fungi.
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Affiliation(s)
- Sebastian Müller
- Leibniz Institute for Natural Product Research and Infection Biology e.V., -Hans Knoell Institute-, Jena, Germany
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Role of carnitine acetyltransferases in acetyl coenzyme A metabolism in Aspergillus nidulans. EUKARYOTIC CELL 2011; 10:547-55. [PMID: 21296915 DOI: 10.1128/ec.00295-10] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The flow of carbon metabolites between cellular compartments is an essential feature of fungal metabolism. During growth on ethanol, acetate, or fatty acids, acetyl units must enter the mitochondrion for metabolism via the tricarboxylic acid cycle, and acetyl coenzyme A (acetyl-CoA) in the cytoplasm is essential for the biosynthetic reactions and for protein acetylation. Acetyl-CoA is produced in the cytoplasm by acetyl-CoA synthetase during growth on acetate and ethanol while β-oxidation of fatty acids generates acetyl-CoA in peroxisomes. The acetyl-carnitine shuttle in which acetyl-CoA is reversibly converted to acetyl-carnitine by carnitine acetyltransferase (CAT) enzymes is important for intracellular transport of acetyl units. In the filamentous ascomycete Aspergillus nidulans, a cytoplasmic CAT, encoded by facC, is essential for growth on sources of cytoplasmic acetyl-CoA while a second CAT, encoded by the acuJ gene, is essential for growth on fatty acids as well as acetate. We have shown that AcuJ contains an N-terminal mitochondrial targeting sequence and a C-terminal peroxisomal targeting sequence (PTS) and is localized to both peroxisomes and mitochondria, independent of the carbon source. Mislocalization of AcuJ to the cytoplasm does not result in loss of growth on acetate but prevents growth on fatty acids. Therefore, while mitochondrial AcuJ is essential for the transfer of acetyl units to mitochondria, peroxisomal localization is required only for transfer from peroxisomes to mitochondria. Peroxisomal AcuJ was not required for the import of acetyl-CoA into peroxisomes for conversion to malate by malate synthase (MLS), and export of acetyl-CoA from peroxisomes to the cytoplasm was found to be independent of FacC when MLS was mislocalized to the cytoplasm.
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Ceccaroli P, Buffalini M, Saltarelli R, Barbieri E, Polidori E, Ottonello S, Kohler A, Tisserant E, Martin F, Stocchi V. Genomic profiling of carbohydrate metabolism in the ectomycorrhizal fungus Tuber melanosporum. THE NEW PHYTOLOGIST 2011; 189:751-764. [PMID: 21039570 DOI: 10.1111/j.1469-8137.2010.03520.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
• Primary carbohydrate metabolism plays a special role related to carbon/nitrogen exchange, as well as metabolic support of fruiting body development, in ectomycorrhizal macrofungi. In this study, we used information retrieved from the recently sequenced Tuber melanosporum genome, together with transcriptome analysis data and targeted validation experiments, to construct the first genome-wide catalogue of the proteins supporting carbohydrate metabolism in a plant-symbiotic ascomycete. • More than 100 genes coding for enzymes of the glycolysis, pentose phosphate, tricarboxylic acid, glyoxylate and methylcitrate pathways, glycogen, trehalose and mannitol metabolism and cell wall precursor were annotated. Transcriptional regulation of these pathways in different stages of the T. melanosporum lifecycle was investigated using whole-genome oligoarray expression data together with real-time reverse transcription-polymerase chain reaction analysis of selected genes. • The most significant results were the identification of methylcitrate cycle genes and of an acid invertase, the first enzyme of this kind to be described in a plant-symbiotic filamentous fungus. • A subset of transcripts coding for trehalose, glyoxylate and methylcitrate enzymes was up-regulated in fruiting bodies, whereas genes involved in mannitol and glycogen metabolism were preferentially expressed in mycelia and ectomycorrhizas, respectively. These data indicate a high degree of lifecycle stage specialization for particular branches of carbohydrate metabolism in T. melanosporum.
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Affiliation(s)
- P Ceccaroli
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino 'Carlo Bo', via Saffi, 2, 61029 Urbino, Italy
| | - M Buffalini
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino 'Carlo Bo', via Saffi, 2, 61029 Urbino, Italy
| | - R Saltarelli
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino 'Carlo Bo', via Saffi, 2, 61029 Urbino, Italy
| | - E Barbieri
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino 'Carlo Bo', via Saffi, 2, 61029 Urbino, Italy
| | - E Polidori
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino 'Carlo Bo', via Saffi, 2, 61029 Urbino, Italy
| | - S Ottonello
- Dipartimento di Biochimica e Biologia Molecolare, Università degli Studi di Parma, Viale G.P. Usberti 23/A, 43100 Parma, Italy
| | - A Kohler
- INRA, UMR 1136, INRA-Nancy Université, Interactions Arbres/Microorganismes, 54280 Champenoux, France
| | - E Tisserant
- INRA, UMR 1136, INRA-Nancy Université, Interactions Arbres/Microorganismes, 54280 Champenoux, France
| | - F Martin
- INRA, UMR 1136, INRA-Nancy Université, Interactions Arbres/Microorganismes, 54280 Champenoux, France
| | - V Stocchi
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino 'Carlo Bo', via Saffi, 2, 61029 Urbino, Italy
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Peplinski K, Ehrenreich A, Döring C, Bömeke M, Steinbüchel A. Investigations on the microbial catabolism of the organic sulfur compounds TDP and DTDP in Ralstonia eutropha H16 employing DNA microarrays. Appl Microbiol Biotechnol 2010; 88:1145-59. [PMID: 20924576 PMCID: PMC3128720 DOI: 10.1007/s00253-010-2915-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 09/05/2010] [Accepted: 09/08/2010] [Indexed: 11/27/2022]
Abstract
In this study, we have investigated the transcriptome of Ralstonia eutropha H16 during cultivation with gluconate in presence of 3,3′-thiodipropionic acid (TDP) or 3,3′-dithiodipropionic acid (DTDP) during biosynthesis of poly(3-hydroxybutyrate-co-3-mercaptopropionate). Genome-wide transcriptome analyses revealed several genes which were upregulated during cultivation in presence of the above-mentioned compounds. Obtained data strongly suggest that two ABC-type transport system and three probable extracytoplasmic solute receptors mediate the uptake of TDP and DTDP, respectively. In addition, genes encoding the hydrolase S-adenosylhomocysteinase AhcY and the thiol-disulfide interchange proteins DsbA, DsbD, and FrnE were upregulated during cultivation on DTDP and, in case of AhcY and FrnE, on TDP as well. It is assumed that the corresponding enzymes are involved in the cleavage of TDP and DTDP. Several genes of the fatty acid metabolism exhibited increased expression levels: genes encoding two acetyltransferases, a predicted acyltransferase, the acetoacetyl-CoA reductase phaB3, an enoyl-CoA hydratase as well as an acyl dehydratase, an acetyl-CoA synthetase, two acyl-CoA dehydrogenases, the methylmalonyl-CoA mutase encoded by sbm1 and sbm2 and phaY1 were detected. Furthermore, ORF H16_A0217 encoding a hypothetical protein and exhibiting 54% amino acids identical to an acyl-CoA thioesterase from Saccharomonospora viridis was found to be highly upregulated. As the 2-methylcitrate synthase PrpC exhibited a three- to fourfold increased activity in cells grown in presence of TDP or DTDP as compared to gluconate, metabolization of the cleavage products 3MP and 3-hydroxypropionate to propionyl-CoA is proposed.
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Affiliation(s)
- Katja Peplinski
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 3, 48149 Münster, Germany
| | - Armin Ehrenreich
- Institut für Mikrobiologie, Technische Universität München, Am Hochanger 4, 85354 Freising, Germany
| | - Christina Döring
- Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Mechthild Bömeke
- Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Alexander Steinbüchel
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 3, 48149 Münster, Germany
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Roze LV, Chanda A, Laivenieks M, Beaudry RM, Artymovich KA, Koptina AV, Awad DW, Valeeva D, Jones AD, Linz JE. Volatile profiling reveals intracellular metabolic changes in Aspergillus parasiticus: veA regulates branched chain amino acid and ethanol metabolism. BMC BIOCHEMISTRY 2010; 11:33. [PMID: 20735852 PMCID: PMC2939540 DOI: 10.1186/1471-2091-11-33] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Accepted: 08/24/2010] [Indexed: 01/17/2023]
Abstract
Background Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. Results Volatile compounds were examined using solid phase microextraction - gas chromatography/mass spectrometry. In the wild type strain Aspergillus parasiticus SU-1, the largest group of volatiles included compounds derived from catabolism of branched chain amino acids (leucine, isoleucine, and valine); we also identified alcohols, esters, aldehydes, and lipid-derived volatiles. The number and quantity of the volatiles produced depended on media composition, time of incubation, and light-dark status. A block in aflatoxin biosynthesis or disruption of the global regulator veA affected the volatile profile. In addition to its multiple functions in secondary metabolism and development, VeA negatively regulated catabolism of branched chain amino acids and synthesis of ethanol at the transcriptional level thus playing a role in controlling carbon flow within the cell. Finally, we demonstrated that volatiles generated by a veA disruption mutant are part of the complex regulatory machinery that mediates the effects of VeA on asexual conidiation and sclerotia formation. Conclusions 1) Volatile profiling provides a rapid, effective, and powerful approach to identify changes in intracellular metabolic networks in filamentous fungi. 2) VeA coordinates the biosynthesis of secondary metabolites with catabolism of branched chain amino acids, alcohol biosynthesis, and β-oxidation of fatty acids. 3) Intracellular chemical development in A. parasiticus is linked to morphological development. 4) Understanding carbon flow through secondary metabolic pathways and catabolism of branched chain amino acids is essential for controlling and customizing production of natural products.
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Affiliation(s)
- Ludmila V Roze
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI, USA.
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Differential expression of citA gene encoding the mitochondrial citrate synthase of Aspergillus nidulans in response to developmental status and carbon sources. J Microbiol 2010; 48:188-98. [PMID: 20437151 DOI: 10.1007/s12275-010-0096-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 04/19/2010] [Indexed: 10/19/2022]
Abstract
As an extension of our previous studies on the mitochondrial citrate synthase of Aspergillus nidulans and cloning of its coding gene (citA), we analyzed differential expression of citA in response to the progress of development and change of carbon source. The cDNA consisted of 1,700 nucleotides and was predicted to encode a 474-amino acid protein. By comparing the cDNA sequence with the corresponding genomic sequence, we confirmed that citA gene contains 7 introns and that its transcription starts at position -26 (26-nucleotide upstream from the initiation codon). Four putative CreA binding motifs and three putative stress-response elements (STREs) were found within the 1.45-kb citA promoter region. The mode of citA expression was examined by both Northern blot and confocal microscopy using green fluorescent protein (sGFP) as a vital reporter. During vegetative growth and asexual development, the expression of citA was ubiquitous throughout the whole fungal body including mycelia and conidiophores. During sexual development, the expression of citA was quite strong in cleistothecial shells, but significantly weak in the content of cleistothecia including ascospores. Acetate showed a strong inductive effect on citA expression, which is subjected to carbon catabolite repression (CCR) caused by glucose. The recombinant fusion protein CitA(40)::sGFP (sGFP containing the 40-amino acid N-terminal segment of CitA) was localized into mitochondria, which supports that a mitochondrial targeting signal is included within the 40-amino acid N-terminal segment of CitA.
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Metabolic and developmental effects resulting from deletion of the citA gene encoding citrate synthase in Aspergillus nidulans. EUKARYOTIC CELL 2010; 9:656-66. [PMID: 20173036 DOI: 10.1128/ec.00373-09] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Citrate synthase is a central activity in carbon metabolism. It is required for the tricarboxylic acid (TCA) cycle, respiration, and the glyoxylate cycle. In Saccharomyces cerevisiae and Arabidopsis thaliana, there are mitochondrial and peroxisomal isoforms encoded by separate genes, while in Aspergillus nidulans, a single gene, citA, encodes a protein with predicted mitochondrial and peroxisomal targeting sequences (PTS). Deletion of citA results in poor growth on glucose but not on derepressing carbon sources, including those requiring the glyoxylate cycle. Growth on glucose is restored by a mutation in the creA carbon catabolite repressor gene. Methylcitrate synthase, required for propionyl-coenzyme A (CoA) metabolism, has previously been shown to have citrate synthase activity. We have been unable to construct the mcsADelta citADelta double mutant, and the expression of mcsA is subject to CreA-mediated carbon repression. Therefore, McsA can substitute for the loss of CitA activity. Deletion of citA does not affect conidiation or sexual development but results in delayed conidial germination as well as a complete loss of ascospores in fruiting bodies, which can be attributed to loss of meiosis. These defects are suppressed by the creA204 mutation, indicating that McsA activity can substitute for the loss of CitA. A mutation of the putative PTS1-encoding sequence in citA had no effect on carbon source utilization or development but did result in slower colony extension arising from single conidia or ascospores. CitA-green fluorescent protein (GFP) studies showed mitochondrial localization in conidia, ascospores, and hyphae. Peroxisomal localization was not detected. However, a very low and variable detection of punctate GFP fluorescence was sometimes observed in conidia germinated for 5 h when the mitochondrial targeting sequence was deleted.
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Domin N, Wilson D, Brock M. Methylcitrate cycle activation during adaptation of Fusarium solani and Fusarium verticillioides to propionyl-CoA-generating carbon sources. MICROBIOLOGY-SGM 2009; 155:3903-3912. [PMID: 19661181 DOI: 10.1099/mic.0.031781-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Propionyl-CoA is an inhibitor of both primary and secondary metabolism in Aspergillus species and a functional methylcitrate cycle is essential for the efficient removal of this potentially toxic metabolite. Although the genomes of most sequenced fungal species appear to contain genes coding for enzymes of the methylcitrate cycle, experimental confirmation of pathway activity in filamentous fungi has only been provided for Aspergillus nidulans and Aspergillus fumigatus. In this study we demonstrate that pathogenic Fusarium species also possess a functional methylcitrate cycle. Fusarium solani appears highly adapted to saprophytic growth as it utilized propionate with high efficiency, whereas Fusarium verticillioides grew poorly on this carbon source. In order to elucidate the mechanisms of propionyl-CoA detoxification, we first identified the genes coding for methylcitrate synthase from both species. Despite sharing 96 % amino acid sequence identity, analysis of the two purified enzymes demonstrated that their biochemical properties differed in several respects. Both methylcitrate synthases exhibited low K(m) values for propionyl-CoA, but that of F. verticillioides displayed significantly higher citrate synthase activity and greater thermal stability. Activity determinations from cell-free extracts of F. solani revealed a strong methylcitrate synthase activity during growth on propionate and to a lesser extent on Casamino acids, whereas activity by F. verticillioides was highest on Casamino acids. Further phenotypic analysis confirmed that these biochemical differences were reflected in the different growth behaviour of the two species on propionyl-CoA-generating carbon sources.
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Affiliation(s)
- Nicole Domin
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Beutenbergstr. 11a, 07745 Jena, Germany
| | - Duncan Wilson
- Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Beutenbergstr. 11a, 07745 Jena, Germany
| | - Matthias Brock
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Beutenbergstr. 11a, 07745 Jena, Germany
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Lee SH, Han YK, Yun SH, Lee YW. Roles of the glyoxylate and methylcitrate cycles in sexual development and virulence in the cereal pathogen Gibberella zeae. EUKARYOTIC CELL 2009; 8:1155-64. [PMID: 19525419 PMCID: PMC2725564 DOI: 10.1128/ec.00335-08] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2008] [Accepted: 06/01/2009] [Indexed: 11/20/2022]
Abstract
The glyoxylate and methylcitrate cycles are involved in the metabolism of two- or three-carbon compounds in fungi. To elucidate the role(s) of these pathways in Gibberella zeae, which causes head blight in cereal crops, we focused on the functions of G. zeae orthologs (GzICL1 and GzMCL1) of the genes that encode isocitrate lyase (ICL) and methylisocitrate lyase (MCL), respectively, key enzymes in each cycle. The deletion of GzICL1 (DeltaGzICL1) caused defects in growth on acetate and in perithecium (sexual fruiting body) formation but not in virulence on barley and wheat, indicating that GzICL1 acts as the ICL of the glyoxylate cycle and is essential for self-fertility in G. zeae. In contrast, the DeltaGzMCL1 strains failed to grow on propionate but exhibited no major changes in other traits, suggesting that GzMCL1 is required for the methylcitrate cycle in G. zeae. Interestingly, double deletion of both GzICL1 and GzMCL1 caused significantly reduced virulence on host plants, indicating that both GzICL1 and GzMCL1 have redundant functions for plant infection in G. zeae. Thus, both GzICL1 and GzMCL1 may play important roles in determining major mycological and pathological traits of G. zeae by participating in different metabolic pathways for the use of fatty acids.
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Affiliation(s)
- Seung-Ho Lee
- Department of Agricultural Biotechnology, Centers for Fungal Pathogenesis and Agricultural Biomaterials, Seoul National University, South Korea
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Crystal structure and putative mechanism of 3-methylitaconate-delta-isomerase from Eubacterium barkeri. J Mol Biol 2009; 391:609-20. [PMID: 19559030 DOI: 10.1016/j.jmb.2009.06.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 06/17/2009] [Accepted: 06/17/2009] [Indexed: 11/22/2022]
Abstract
3-Methylitaconate-Delta-isomerase (Mii) participates in the nicotinate fermentation pathway of the anaerobic soil bacterium Eubacterium barkeri (order Clostridiales) by catalyzing the reversible conversion of (R)-3-methylitaconate (2-methylene-3-methylsuccinate) to 2,3-dimethylmaleate. The enzyme is also able to catalyze the isomerization of itaconate (methylenesuccinate) to citraconate (methylmaleate) with ca 10-fold higher K(m) but > 1000-fold lower k(cat). The gene mii from E. barkeri was cloned and expressed in Escherichia coli. The protein produced with a C-terminal Strep-tag exhibited the same specific activity as the wild-type enzyme. The crystal structure of Mii from E. barkeri has been solved at a resolution of 2.70 A. The asymmetric unit of the P2(1)2(1)2(1) unit cell with parameters a = 53.1 A, b = 142.3 A, and c = 228.4 A contains four molecules of Mii. The enzyme belongs to a group of isomerases with a common structural feature, the so-called diaminopimelate epimerase fold. The monomer of 380 amino acid residues has two topologically similar domains exhibiting an alpha/beta-fold. The active site is situated in a cleft between these domains. The four Mii molecules are arranged as a tetramer with 222 symmetry for the N-terminal domains. The C-terminal domains have different relative positions with respect to the N-terminal domains resulting in a closed conformation for molecule A and two distinct open conformations for molecules B and D. The C-terminal domain of molecule C is disordered. The Mii active site contains the putative catalytic residues Lys62 and Cys96, for which mechanistic roles are proposed based on a docking experiment of the Mii substrate complex. The active sites of Mii and the closely related PrpF, most likely a methylaconitate Delta-isomerase, have been compared. The overall architecture including the active-site Lys62, Cys96, His300, and Ser17 (Mii numbering) is similar. This positioning of (R)-3-methylitaconate allows Cys96 (as thiolate) to deprotonate C-3 and (as thiol) to donate a proton to the methylene carbon atom of the resulting allylic carbanion. Interestingly, the active site of isopentenyl diphosphate isomerase type I also contains a cysteine that cooperates with glutamate rather than lysine. It has been proposed that the initial step in this enzyme is a protonation generating a tertiary carbocation intermediate.
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Fleck CB, Brock M. Re-characterisation of Saccharomyces cerevisiae Ach1p: fungal CoA-transferases are involved in acetic acid detoxification. Fungal Genet Biol 2009; 46:473-85. [PMID: 19298859 DOI: 10.1016/j.fgb.2009.03.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 03/06/2009] [Accepted: 03/07/2009] [Indexed: 11/16/2022]
Abstract
Saccharomyces cerevisiae and Neurospora crassa mutants defective in the so-called acetyl-CoA hydrolases Ach1p and Acu-8, respectively, display a severe growth defect on acetate, which is most strongly pronounced under acidic conditions. Acetyl-CoA hydrolysis is an energy wasting process and therefore denoted as a biochemical conundrum. Acetyl-CoA hydrolases show high sequence identity to the CoA-transferase CoaT from Aspergillus nidulans. Therefore, we extensively re-characterised the yeast enzyme. Ach1p showed highest specific activity for the CoASH transfer from succinyl-CoA to acetate and only a minor acetyl-CoA-hydrolase activity. Complementation of an ach1 mutant with the coaT gene reversed the growth defect on acetate confirming the in vivo function of Ach1p as a CoA-transferase. Our results imply that Ach1p is involved in mitochondrial acetate detoxification by a CoASH transfer from succinyl-CoA to acetate. Thereby, Ach1p does not perform the energy wasting hydrolysis of acetyl-CoA but conserves energy by the detoxification of mitochondrial acetate.
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Affiliation(s)
- Christian B Fleck
- Leibniz Institute for Natural Product Research and Infection Biology e.V., -Hans Knoell Institute-, Research Group Microbial Biochemistry and Physiology, Jena, Germany
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Fleck CB, Brock M. Characterization of an acyl-CoA: carboxylate CoA-transferase from Aspergillus nidulans involved in propionyl-CoA detoxification. Mol Microbiol 2008; 68:642-56. [PMID: 18331473 DOI: 10.1111/j.1365-2958.2008.06180.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Filamentous fungi metabolize toxic propionyl-CoA via the methylcitrate cycle. Disruption of the methylcitrate synthase gene leads to an accumulation of propionyl-CoA and attenuates virulence of Aspergillus fumigatus. However, addition of acetate, but not ethanol, to propionate-containing medium strongly reduces the accumulation of propionyl-CoA and restores growth of the methylcitrate synthase mutant. Therefore, the existence of a CoA-transferase was postulated, which transfers the CoASH moiety from propionyl-CoA to acetate and, thereby, detoxifying the cell. In this study, we purified the responsible protein from Aspergillus nidulans and characterized its biochemical properties. The enzyme used succinyl-, propionyl- and acetyl-CoA as CoASH donors and the corresponding acids as acceptor molecules. Although the protein displayed high sequence similarity to acetyl-CoA hydrolases this activity was hardly detectable. We additionally identified and deleted the coding DNA sequence of the CoA-transferase. The mutant displayed weak phenotypes in the presence of propionate and behaved like the wild type when no propionate was present. However, when a double-deletion mutant defective in both methylcitrate synthase and CoA-transferase was constructed, the resulting strain was unable to grow on media containing acetate and propionate as sole carbon sources, which confirmed the in vivo activity of the CoA-transferase.
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Affiliation(s)
- Christian B Fleck
- Leibniz Institute for Natural Product Research and Infection Biology e.V., Hans Knoell Institute, Beutenbergstr. 11a, D-07745 Jena, Germany
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Upton AM, McKinney JD. Role of the methylcitrate cycle in propionate metabolism and detoxification in Mycobacterium smegmatis. MICROBIOLOGY-SGM 2008; 153:3973-3982. [PMID: 18048912 DOI: 10.1099/mic.0.2007/011726-0] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Catabolism of odd-chain-length fatty acids yields acetyl-CoA and propionyl-CoA. A common pathway of propionyl-CoA metabolism in micro-organisms is the methylcitrate cycle, which includes the dedicated enzymes methylcitrate synthase (MCS), methylcitrate dehydratase (MCD) and methylisocitrate lyase (MCL). The methylcitrate cycle is essential for propionate metabolism in Mycobacterium tuberculosis. Unusually, M. tuberculosis lacks an MCL orthologue and this activity is provided instead by two isoforms of the glyoxylate cycle enzyme isocitrate lyase (ICL1 and ICL2). These bifunctional (ICL/MCL) enzymes are jointly required for propionate metabolism and for growth and survival in mice. In contrast, the non-pathogenic species Mycobacterium smegmatis encodes a canonical MCL enzyme in addition to ICL1 and ICL2. The M. smegmatis gene encoding MCL (prpB) is clustered with genes encoding MCS (prpC) and MCD (prpD). Here we show that deletion of the M. smegmatis prpDBC locus reduced but did not eliminate MCL activity in cell-free extracts. The residual MCL activity was abolished by deletion of icl1 and icl2 in the DeltaprpDBC background, suggesting that these genes encode bifunctional ICL/MCL enzymes. A DeltaprpB Deltaicl1 Deltaicl2 mutant was unable to grow on propionate or mixtures of propionate and glucose. We hypothesize that incomplete propionyl-CoA metabolism might cause toxic metabolites to accumulate. Consistent with this idea, deletion of prpC and prpD in the DeltaprpB Deltaicl1 Deltaicl2 background paradoxically restored growth on propionate-containing media. These observations suggest that the marked attenuation of ICL1/ICL2-deficient M. tuberculosis in mice could be due to the accumulation of toxic propionyl-CoA metabolites, rather than inability to utilize fatty acids per se.
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Affiliation(s)
- Anna M Upton
- Laboratory of Infection Biology, The Rockefeller University, New York, NY 10021, USA
| | - John D McKinney
- Laboratory of Infection Biology, The Rockefeller University, New York, NY 10021, USA
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Ibrahim-Granet O, Dubourdeau M, Latgé JP, Ave P, Huerre M, Brakhage AA, Brock M. Methylcitrate synthase from Aspergillus fumigatus is essential for manifestation of invasive aspergillosis. Cell Microbiol 2008; 10:134-48. [PMID: 17973657 DOI: 10.1111/j.1462-5822.2007.01025.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Invasive aspergillosis is a life-threatening disease mainly caused by the fungus Aspergillus fumigatus. In immunocompromised individuals conidia are not efficiently inactivated, which can end in invasive fungal growth. However, the metabolic requirements of the fungus are hardly known. Earlier investigations revealed an accumulation of toxic propionyl-CoA in a methylcitrate synthase mutant, when grown on propionyl-CoA-generating carbon sources. During invasive growth propionyl-CoA could derive from proteins, which are released from infected host tissues. We therefore assumed that a methylcitrate synthase mutant might display an attenuated virulence. Here we show that the addition of propionate to cell culture medium enhanced the ability of alveolar macrophages to kill methylcitrate synthase mutant but not wild-type conidia. When tested in a murine infection model, the methylcitrate synthase mutant displayed attenuated virulence and, furthermore, was cleared from tissues when mice survived the first phase of acute infection. The amplification of cDNA from infected mouse lungs confirmed the transcription of the methylcitrate synthase gene during invasion, which leads to the suggestion that amino acids indeed serve as growth-supporting nutrients during invasive growth of A. fumigatus. Thus, blocking of methylcitrate synthase activity abrogates fungal growth and provides a suitable target for new antifungals.
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Genetic analysis of the role of peroxisomes in the utilization of acetate and fatty acids in Aspergillus nidulans. Genetics 2008; 178:1355-69. [PMID: 18245820 DOI: 10.1534/genetics.107.085795] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Peroxisomes are organelles containing a diverse array of enzymes. In fungi they are important for carbon source utilization, pathogenesis, development, and secondary metabolism. We have studied Aspergillus nidulans peroxin (pex) mutants isolated by virtue of their inability to grow on butyrate or by the inactivation of specific pex genes. While all pex mutants are able to form colonies, those unable to import PTS1 proteins are partially defective in asexual and sexual development. The pex mutants are able to grow on acetate but are affected in growth on fatty acids, indicating a requirement for the peroxisomal localization of beta-oxidation enzymes. However, mislocalization of malate synthase does not prevent growth on either fatty acids or acetate, showing that the glyoxylate cycle does not require peroxisomal localization. Proliferation of peroxisomes is dependent on fatty acids, but not on acetate, and on PexK (Pex11), expression of which is activated by the FarA transcription factor. Proliferation was greatly reduced in a farADelta strain. A mutation affecting a mitochodrial ketoacyl-CoA thiolase and disruption of a mitochondrial hydroxy-acyl-CoA dehydrogenase gene prevented growth on short-chain but not long-chain fatty acids. Together with previous results, this is consistent with growth on even-numbered short-chain fatty acids requiring a mitochondrial as well as a peroxisomal beta-oxidation pathway. The mitochondrial pathway is not required for growth on valerate or for long-chain fatty acid utilization.
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Plassmeier J, Barsch A, Persicke M, Niehaus K, Kalinowski J. Investigation of central carbon metabolism and the 2-methylcitrate cycle in Corynebacterium glutamicum by metabolic profiling using gas chromatography–mass spectrometry. J Biotechnol 2007; 130:354-63. [PMID: 17586079 DOI: 10.1016/j.jbiotec.2007.04.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Revised: 04/18/2007] [Accepted: 04/25/2007] [Indexed: 10/23/2022]
Abstract
The 2-methylcitrate cycle as the primary way to metabolize propionate was investigated using metabolic profiling. For this purpose, a fast harvesting procedure was applied in which cells growing in liquid minimal medium were harvested by a short centrifugation and freeze-dried. Subsequently, gas chromatography-mass spectrometry of polar extracts derivatized by MSTFA was employed for metabolite characterization. Routinely more than 300 different peaks were obtained in the chromatograms, and 74 substances were identified unequivocally by using pure standards. The procedure provided reliable data which closely relate to prior knowledge on flux distributions during growth on glucose and acetate as carbon sources. Propionate degradation via the 2-methylcitrate cycle was demonstrated on the metabolite level by the detection of the intermediates 2-methylcitrate and 2-methylisocitrate. Further characterization of the 2-methylcitrate cycle was carried out by comparing different mutant strains of this pathway. The growth deficit of a prpD2-mutant strain observed when propionate is added to a culture growing on acetate indicates that the toxic effect of propionate is based on the accumulation of 2-methylcitrate. It could also be shown that the 2-methylcitrate cycle is active in the absence of propionate and might fulfill house-keeping functions in the degradation of fatty acids or branched-chain amino acids.
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Affiliation(s)
- Jens Plassmeier
- Institut für Genomforschung und Systembiologie, Centrum für Biotechnologie, Universität Bielefeld, D-33594 Bielefeld, Germany
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Bailão AM, Shrank A, Borges CL, Parente JA, Dutra V, Felipe MSS, Fiúza RB, Pereira M, de Almeida Soares CM. The transcriptional profile of Paracoccidioides brasiliensis yeast cells is influenced by human plasma. ACTA ACUST UNITED AC 2007; 51:43-57. [PMID: 17608708 DOI: 10.1111/j.1574-695x.2007.00277.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Paracoccidioides brasiliensis causes infection through host inhalation of airborne propagules of the mycelial phase of the fungus, which reach the lungs, and then disseminate to virtually all parts of the human body. Here we describe the identification of differentially expressed genes in P. brasiliensis yeast cells, by analyzing cDNA populations from the fungus treated with human plasma, mimicking superficial infection sites with inflammation. Our analysis identified transcripts that are differentially represented. The transcripts upregulated in yeast cells during incubation in human plasma were predominantly related to fatty acid degradation, protein synthesis, sensing of osmolarity changes, cell wall remodeling and cell defense. The expression pattern of genes was independently confirmed.
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Affiliation(s)
- Alexandre Melo Bailão
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
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48
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Maggio-Hall LA, Lyne P, Wolff JA, Keller NP. A single acyl-CoA dehydrogenase is required for catabolism of isoleucine, valine and short-chain fatty acids in Aspergillus nidulans. Fungal Genet Biol 2007; 45:180-9. [PMID: 17656140 PMCID: PMC2905684 DOI: 10.1016/j.fgb.2007.06.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2007] [Revised: 06/01/2007] [Accepted: 06/04/2007] [Indexed: 01/04/2023]
Abstract
An acyl-CoA dehydrogenase has been identified as part of the mitochondrial beta-oxidation pathway in the ascomycete fungus Aspergillus nidulans. Disruption of the scdA gene prevented use of butyric acid (C(4)) and hexanoic acid (C(6)) as carbon sources and reduced cellular butyryl-CoA dehydrogenase activity by 7.5-fold. While the mutant strain exhibited wild-type levels of growth on erucic acid (C(22:1)) and oleic acid (C(18:1)), some reduction in growth was observed with myristic acid (C(14)). The DeltascdA mutation was found to be epistatic to a mutation downstream in the beta-oxidation pathway (disruption of enoyl-CoA hydratase). The DeltascdA mutant was also unable to use isoleucine or valine as a carbon source. Transcription of scdA was observed in the presence of either fatty acids or amino acids. When the mutant was grown in medium containing either isoleucine or valine, organic acid analysis of culture supernatants showed accumulation of 2-oxo acid intermediates of branched chain amino acid catabolism, suggesting feedback inhibition of the upstream branched-chain alpha-keto acid dehydrogenase.
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Affiliation(s)
- Lori A. Maggio-Hall
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Paul Lyne
- Department of Pediatrics, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Jon A. Wolff
- Department of Pediatrics, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Nancy P. Keller
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin 53706
- Corresponding author: 882 Russell Labs, 1630 Linden Drive, Madison, Wisconsin 53706; Telephone: 608-262-9795; Fax: 608-263-2626;
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Graybill ER, Rouhier MF, Kirby CE, Hawes JW. Functional comparison of citrate synthase isoforms from S. cerevisiae. Arch Biochem Biophys 2007; 465:26-37. [PMID: 17570335 DOI: 10.1016/j.abb.2007.04.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 04/27/2007] [Accepted: 04/30/2007] [Indexed: 10/23/2022]
Abstract
In this study, the product of the CIT3 gene has been identified as a dual specificity mitochondrial citrate and methylcitrate synthase and that of the CIT1 gene as a specific citrate synthase. Recombinant Cit1p had catalytic activity only with acetyl-CoA whereas Cit3p had similar catalytic efficiency with both acetyl-CoA and propionyl-CoA. Deletion of CIT1 dramatically shifted the ratio of these two activities in whole cell extracts towards greater methylcitrate synthase. Deletion of CIT3 had little effect on either citrate or methylcitrate synthase activities. A Deltacit2Deltacit3 strain showed no methylcitrate synthase activity, suggesting that Cit2p, a peroxisomal isoform, may also have methylcitrate synthase activity. Although wild-type strains of Saccharomyces cerevisiae did not grow with propionate as a sole carbon source, deletion of CIT2 allowed growth on propionate, suggesting a toxic production of methylcitrate in the peroxisomes of wild-type cells. The Deltacit2Deltacit3 double mutant did not grow on propionate, providing further evidence for the role of Cit3p in propionate metabolism. (13)C NMR analysis showed the metabolism of 2-(13)C-propionate to acetate, pyruvate, and alanine in wild-type, Deltacit1 and Deltacit2 cells, but not in the Deltacit3 mutant. (13)C NMR and GC-MS analysis of pyruvate metabolism revealed an accumulation of acetate and of isobutanol in the Deltacit3 mutant, suggesting a metabolic alteration possibly resulting from inhibition of the lipoamide acetyltransferase subunit of the pyruvate dehydrogenase complex by propionyl-CoA. In contrast to Deltacit3, pyruvate metabolism in a Deltapda1 (pyruvate dehydrogenase E1 alpha subunit) mutant strain was only shifted towards accumulation of acetate.
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Affiliation(s)
- Eric R Graybill
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
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Hynes MJ, Szewczyk E, Murray SL, Suzuki Y, Davis MA, Sealy-Lewis HM. Transcriptional control of gluconeogenesis in Aspergillus nidulans. Genetics 2007; 176:139-50. [PMID: 17339216 PMCID: PMC1893031 DOI: 10.1534/genetics.107.070904] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2007] [Accepted: 02/16/2007] [Indexed: 11/18/2022] Open
Abstract
Aspergillus nidulans can utilize carbon sources that result in the production of TCA cycle intermediates, thereby requiring gluconeogenesis. We have cloned the acuG gene encoding fructose-1,6 bisphosphatase and found that expression of this gene is regulated by carbon catabolite repression as well as by induction by a TCA cycle intermediate similar to the induction of the previously studied acuF gene encoding phosphoenolpyruvate carboxykinase. The acuN356 mutation results in loss of growth on gluconeogenic carbon sources. Cloning of acuN has shown that it encodes enolase, an enzyme involved in both glycolysis and gluconeogenesis. The acuN356 mutation is a translocation with a breakpoint in the 5' untranslated region resulting in loss of expression in response to gluconeogenic but not glycolytic carbon sources. Mutations in the acuK and acuM genes affect growth on carbon sources requiring gluconeogenesis and result in loss of induction of the acuF, acuN, and acuG genes by sources of TCA cycle intermediates. Isolation and sequencing of these genes has shown that they encode proteins with similar but distinct Zn(2) Cys(6) DNA-binding domains, suggesting a direct role in transcriptional control of gluconeogenic genes. These genes are conserved in other filamentous ascomycetes, indicating their significance for the regulation of carbon source utilization.
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Affiliation(s)
- Michael J Hynes
- Department of Genetics, University of Melbourne, Victoria, Australia.
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