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Rajput A, Manna T, Husain SM. Anthrol reductases: discovery, role in biosynthesis and applications in natural product syntheses. Nat Prod Rep 2023; 40:1672-1686. [PMID: 37475701 DOI: 10.1039/d3np00027c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
Covering: up to 2023Short-chain dehydrogenase/reductases (SDR) are known to catalyze the regio- and stereoselective reduction of a variety of substrate types. Investigations of the deoxygenation of emodin to chrysophanol has led to the discovery of the anthrol reductase activity of an SDR, MdpC involved in monodictyphenone biosynthesis of Aspergillus nidulans and provided access to (R)-dihydroanthracenone, a putative biosynthetic intermediate. This facilitated the identification of several MdpC-related enzymes involved in the biosynthesis of aflatoxins B1, cladofulvin, neosartorin, agnestins and bisanthraquinones. Because of their ability to catalyze the reduction of hydroanthraquinone (anthrols) using NADPH, they were named anthrol reductases. This review provides a comprehensive summary of all the anthrol reductases that have been identified and characterized in the last decade along with their role in the biosynthesis of natural products. In addition, the applications of these enzymes towards the chemoenzymatic synthesis of flavoskyrins, modified bisanthraquinones, 3-deoxy anthraquinones, chiral cycloketones and β-halohydrins have been discussed.
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Affiliation(s)
- Anshul Rajput
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
| | - Tanaya Manna
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
| | - Syed Masood Husain
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
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2
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Fakhry H, Ghoniem AA, Al-Otibi FO, Helmy YA, El Hersh MS, Elattar KM, Saber WIA, Elsayed A. A Comparative Study of Cr(VI) Sorption by Aureobasidium pullulans AKW Biomass and Its Extracellular Melanin: Complementary Modeling with Equilibrium Isotherms, Kinetic Studies, and Decision Tree Modeling. Polymers (Basel) 2023; 15:3754. [PMID: 37765609 PMCID: PMC10537747 DOI: 10.3390/polym15183754] [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: 08/06/2023] [Revised: 08/27/2023] [Accepted: 08/29/2023] [Indexed: 09/29/2023] Open
Abstract
Melanin as a natural polymer is found in all living organisms, and plays an important role in protecting the body from harmful UV rays from the sun. The efficiency of fungal biomass (Aureobasidium pullulans) and its extracellular melanin as Cr(VI) biosorbents was comparatively considered. The efficiency of Cr(VI) biosorption by the two sorbents used was augmented up to 240 min. The maximum sorption capacities were 485.747 (fungus biomass) and 595.974 (melanin) mg/g. The practical data were merely fitted to both Langmuir and Freundlich isotherms. The kinetics of the biosorption process obeyed the pseudo-first-order. Melanin was superior in Cr(VI) sorption than fungal biomass. Furthermore, four independent variables (contact time, initial concentration of Cr(VI), biosorbent dosage, and pH,) were modeled by the two decision trees (DTs). Conversely, to equilibrium isotherms and kinetic studies, DT of fungal biomass had lower errors compared to DT of melanin. Lately, the DTs improved the efficacy of the Cr(VI) removal process, thus introducing complementary and alternative solutions to equilibrium isotherms and kinetic studies. The Cr(VI) biosorption onto the biosorbents was confirmed and elucidated through FTIR, SEM, and EDX investigations. Conclusively, this is the first report study attaining the biosorption of Cr(VI) by biomass of A. pullulans and its extracellular melanin among equilibrium isotherms, kinetic study, and algorithmic decision tree modeling.
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Affiliation(s)
- Hala Fakhry
- National Institute of Oceanography and Fisheries (NIOF), Cairo 11865, Egypt
- Department of Aquatic Environmental Science, Faculty of Fish Resources, Suez University, Suez 43518, Egypt
| | - Abeer A. Ghoniem
- Microbial Activity Unit, Department of Microbiology, Soils, Water and Environment Research Institute, Agricultural Research Center, Giza 12619, Egypt; (A.A.G.); (M.S.E.H.)
| | - Fatimah O. Al-Otibi
- Botany and Microbiology Department, Faculty of Science, King Saud University, Riyadh 11451, Saudi Arabia;
| | - Yosra A. Helmy
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food, and Environment, University of Kentucky, Lexington, KY 40546, USA;
| | - Mohammed S. El Hersh
- Microbial Activity Unit, Department of Microbiology, Soils, Water and Environment Research Institute, Agricultural Research Center, Giza 12619, Egypt; (A.A.G.); (M.S.E.H.)
| | - Khaled M. Elattar
- Unit of Genetic Engineering and Biotechnology, Faculty of Science, Mansoura University, Mansoura 35516, Egypt;
| | - WesamEldin I. A. Saber
- Microbial Activity Unit, Department of Microbiology, Soils, Water and Environment Research Institute, Agricultural Research Center, Giza 12619, Egypt; (A.A.G.); (M.S.E.H.)
| | - Ashraf Elsayed
- Botany Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt;
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Manna T, Rajput A, Saha N, Mondal A, Debnath SC, Husain SM. Chemoenzymatic total synthesis of nodulones C and D using a naphthol reductase of Magnaporthe grisea. Org Biomol Chem 2022; 20:3737-3741. [PMID: 35468177 DOI: 10.1039/d2ob00401a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Herein, the asymmetric and chemoenzymatic synthesis of (R)-nodulone C, cis-nodulone D and related (R)-dihydronaphthalenone is reported. It involves multistep chemical synthesis of putative biosynthetic substrates followed by regio- and stereoselective reduction using a NADPH-dependent tetrahydroxynaphthalene reductase of Magnaporthe grisea to obtain chiral nodulones in a biomimetic fashion.
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Affiliation(s)
- Tanaya Manna
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Anshul Rajput
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Nirmal Saha
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Amit Mondal
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | | | - Syed Masood Husain
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
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4
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Motoyama T, Kondoh Y, Shimizu T, Hayashi T, Honda K, Uchida M, Osada H. Identification of Scytalone Dehydratase Inhibitors Effective against Melanin Biosynthesis Dehydratase Inhibitor-Resistant Pyricularia oryzae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:3109-3116. [PMID: 35234040 DOI: 10.1021/acs.jafc.1c04984] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Melanin is a secondary metabolite required for the infection of the rice blast fungus Pyricularia oryzae. Melanin biosynthesis enzymes are targets for controlling rice blast disease, and three types of commercial melanin biosynthesis inhibitors (MBIs) including MBI-R, MBI-D, and MBI-P have been developed. However, the occurrence of MBI-D-resistant strains containing scytalone dehydratase (SDH1/RSY1) with V75M mutations has been recently reported. In this study, we aimed to identify inhibitors of SDH1-V75M. We screened the RIKEN Natural Products Depository chemical library using chemical array technology and evaluated the inhibition of SDH1-V75M by candidate compounds. NPD13731 strongly inhibited the activity of wild-type and mutant SDH1. The structure-activity relationship data were used to create a more potent inhibitor 16, which controlled rice blast disease in rice plants infected with MBI-D-resistant P. oryzae. Compound 16, which we named melabiostin, may be used to develop fungicides for controlling rice blast infections.
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Affiliation(s)
- Takayuki Motoyama
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yasumitsu Kondoh
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takeshi Shimizu
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Teruo Hayashi
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kaori Honda
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Motoko Uchida
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Hiroyuki Osada
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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5
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Motoyama T, Yun CS, Osada H. Biosynthesis and biological function of secondary metabolites of the rice blast fungus Pyricularia oryzae. J Ind Microbiol Biotechnol 2021; 48:kuab058. [PMID: 34379774 PMCID: PMC8788799 DOI: 10.1093/jimb/kuab058] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 08/05/2021] [Indexed: 11/18/2022]
Abstract
Filamentous fungi have many secondary metabolism genes and produce a wide variety of secondary metabolites with complex and unique structures. However, the role of most secondary metabolites remains unclear. Moreover, most fungal secondary metabolism genes are silent or poorly expressed under laboratory conditions and are difficult to utilize. Pyricularia oryzae, the causal pathogen of rice blast disease, is a well-characterized plant pathogenic fungus. P. oryzae also has a large number of secondary metabolism genes and appears to be a suitable organism for analyzing secondary metabolites. However, in case of this fungus, biosynthetic genes for only four groups of secondary metabolites have been well characterized. Among two of the four groups of secondary metabolites, biosynthetic genes were identified by activating secondary metabolism. These secondary metabolites include melanin, a polyketide compound required for rice infection; tenuazonic acid, a well-known mycotoxin produced by various plant pathogenic fungi and biosynthesized by a unique nonribosomal peptide synthetase-polyketide synthase hybrid enzyme; nectriapyrones, antibacterial polyketide compounds produced mainly by symbiotic fungi, including plant pathogens and endophytes, and pyriculols, phytotoxic polyketide compounds. This review mainly focuses on the biosynthesis and biological functions of the four groups of P. oryzae secondary metabolites.
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Affiliation(s)
- Takayuki Motoyama
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Choong-Soo Yun
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Hiroyuki Osada
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
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6
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Zaman NR, Chowdhury UF, Reza RN, Chowdhury FT, Sarker M, Hossain MM, Akbor MA, Amin A, Islam MR, Khan H. Plant growth promoting endophyte Burkholderia contaminans NZ antagonizes phytopathogen Macrophomina phaseolina through melanin synthesis and pyrrolnitrin inhibition. PLoS One 2021; 16:e0257863. [PMID: 34591915 PMCID: PMC8483353 DOI: 10.1371/journal.pone.0257863] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 09/14/2021] [Indexed: 11/23/2022] Open
Abstract
The endophytic bacterium Burkholderia contaminans NZ was isolated from jute, which is an important fiber-producing plant. This bacterium exhibits significant growth promotion activity in in vivo pot experiments, and like other plant growth-promoting (PGP) bacteria fixes nitrogen, produces indole acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. B. contaminans NZ is considered to exert a promising growth inhibitory effect on Macrophomina phaseolina, a phytopathogen responsible for infecting hundreds of crops worldwide. This study aimed to identify the possibility of B. contaminans NZ as a safe biocontrol agent and assess its effectiveness in suppressing phytopathogenic fungi, especially M. phaseolina. Co-culture of M. phaseolina with B. contaminans NZ on both solid and liquid media revealed appreciable growth suppression of M. phaseolina and its chromogenic aberration in liquid culture. Genome mining of B. contaminans NZ using NaPDoS and antiSMASH revealed gene clusters that displayed 100% similarity for cytotoxic and antifungal substances, such as pyrrolnitrin. GC-MS analysis of B. contaminans NZ culture extracts revealed various bioactive compounds, including catechol; 9,10-dihydro-12'-hydroxy-2'-methyl-5'-(phenylmethyl)- ergotaman 3',6',18-trione; 2,3-dihydro-3,5- dihydroxy-6-methyl-4H-pyran-4-one; 1-(1,6-Dioxooctadecyl)- pyrrolidine; 9-Octadecenamide; and 2- methoxy- phenol. These compounds reportedly exhibit tyrosinase inhibitory, antifungal, and antibiotic activities. Using a more targeted approach, an RP-HPLC purified fraction was analyzed by LC-MS, confirming the existence of pyrrolnitrin in the B. contaminans NZ extract. Secondary metabolites, such as catechol and ergotaman, have been predicted to inhibit melanin synthesis in M. phaseolina. Thus, B. contaminans NZ appears to inhibit phytopathogens by apparently impairing melanin synthesis and other potential biochemical pathways, exhibiting considerable fungistatic activity.
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Affiliation(s)
- Nazia R. Zaman
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
| | - Umar F. Chowdhury
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
| | - Rifath N. Reza
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
| | - Farhana T. Chowdhury
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
| | - Mrinmoy Sarker
- NSU Genome Research Institute (NGRI), Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | - Muhammad M. Hossain
- NSU Genome Research Institute (NGRI), Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | - Md. Ahedul Akbor
- Institute of National Analytical Research and Service (INARS), Bangladesh Council of Scientific and Industrial Research (BCSIR), Dhaka, Bangladesh
| | - Al Amin
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
| | - Mohammad Riazul Islam
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
| | - Haseena Khan
- Molecular Biology Laboratory, Department of Biochemistry and Molecular Biology, Faculty Biological Sciences, University of Dhaka, Dhaka, Bangladesh
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Motoyama T, Ishii T, Kamakura T, Osada H. Screening of tenuazonic acid production-inducing compounds and identification of NPD938 as a regulator of fungal secondary metabolism. Biosci Biotechnol Biochem 2021; 85:2200-2208. [PMID: 34379730 DOI: 10.1093/bbb/zbab143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/05/2021] [Indexed: 11/12/2022]
Abstract
The control of secondary metabolism in fungi is essential for the regulation of various cellular functions. In this study, we searched the RIKEN Natural Products Depository (NPDepo) chemical library for inducers of tenuazonic acid (TeA) production in the rice blast fungus Pyricularia oryzae and identified NPD938. NPD938 transcriptionally induced TeA production. We explored the mode of action of NPD938 and observed that this compound enhanced TeA production via LAE1, a global regulator of fungal secondary metabolism. NPD938 could also induce production of terpendoles and pyridoxatins in Tolypocladium album RK99-F33. Terpendole production was induced transcriptionally. We identified the pyridoxatin biosynthetic gene cluster among transcriptionally induced secondary metabolite biosynthetic gene clusters. Therefore, NPD938 is useful for the control of fungal secondary metabolism.
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Affiliation(s)
| | - Tomoaki Ishii
- Chemical Biology Research Group, RIKEN CSRS, Wako, Saitama, Japan
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Takashi Kamakura
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Hiroyuki Osada
- Chemical Biology Research Group, RIKEN CSRS, Wako, Saitama, Japan
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8
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Zhu J, Liu M, Deng J, Chen W, Zhu D, Duan J, Li Y, Wang H, Shen Y. The coupled reaction catalyzed by EchB and EchC lead to the formation of the common 2',3',5'-trihydroxy-benzene core in echosides biosynthesis. Biochem Biophys Res Commun 2021; 559:62-69. [PMID: 33932901 DOI: 10.1016/j.bbrc.2021.04.087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 04/21/2021] [Indexed: 11/15/2022]
Abstract
p-Terphenyls represent a unique family of aromatic natural products generated by nonribosomal peptide synthetase-like (NRPS-like) enzyme. After formation of p-terphenyl skeleton, tailoring modifications will give rise to structural diversity and various biological activities. Here we demonstrated a two-enzyme (EchB, a short-chain dehydrogenase/reductase (SDR), and EchC, a nuclear transport factor 2 (NTF2)-like dehydratase) participated transformation from dihydroxybenzoquinone core to 2',3',5'-trihydroxy-benzene in the biosynthesis of echosides. Beginning with polyporic acid as substrate, successive steps of reduction-dehydration-reduction cascade catalyzed by EchB-EchC-EchB were concluded after in vivo gene disruption and in vitro bioassay experiments. These findings demonstrated a conserved synthesis pathway of 2',3',5'-trihydroxy-p-terphenyls in bacteria, such as Actinomycetes and Burkholderia. The parallel pathway in fungi has yet to be explored.
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Affiliation(s)
- Jing Zhu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China
| | - Mengyujie Liu
- Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, PR China
| | - Jingjing Deng
- Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, PR China
| | - Wang Chen
- Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, PR China
| | - Deyu Zhu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, PR China
| | - Jing Duan
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China
| | - Yaoyao Li
- Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, PR China
| | - Haoxin Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China.
| | - Yuemao Shen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China; Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, PR China.
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9
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Yeh YC, Kim HJ, Liu HW. Mechanistic Investigation of 1,2-Diol Dehydration of Paromamine Catalyzed by the Radical S-Adenosyl-l-methionine Enzyme AprD4. J Am Chem Soc 2021; 143:5038-5043. [PMID: 33784078 DOI: 10.1021/jacs.1c00076] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AprD4 is a radical S-adenosyl-l-methionine (SAM) enzyme catalyzing C3'-deoxygenation of paromamine to form 4'-oxo-lividamine. It is the only 1,2-diol dehydratase in the radical SAM enzyme superfamily that has been identified and characterized in vitro. The AprD4 catalyzed 1,2-diol dehydration is a key step in the biosynthesis of several C3'-deoxy-aminoglycosides. While the regiochemistry of the hydrogen atom abstraction catalyzed by AprD4 has been established, the mechanism of the subsequent chemical transformation remains not fully understood. To investigate the mechanism, several substrate analogues were synthesized and their fates upon incubation with AprD4 were analyzed. The results support a mechanism involving formation of a ketyl radical intermediate followed by direct elimination of the C3'-hydroxyl group rather than that of a gem-diol intermediate generated via 1,2-migration of the C3'-hydroxyl group to C4'. The stereochemistry of hydrogen atom incorporation after radical-mediated dehydration was also established.
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Affiliation(s)
- Yu-Cheng Yeh
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Hak Joong Kim
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Hung-Wen Liu
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States.,Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712, United States
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10
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Dulal N, Rogers AM, Proko R, Bieger BD, Liyanage R, Krishnamurthi VR, Wang Y, Egan MJ. Turgor-dependent and coronin-mediated F-actin dynamics drive septin disc-to-ring remodeling in the blast fungus Magnaporthe oryzae. J Cell Sci 2021; 134:jcs.251298. [PMID: 33414165 DOI: 10.1242/jcs.251298] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 12/16/2020] [Indexed: 12/16/2022] Open
Abstract
The fungus Magnaporthe oryzae uses a specialized pressure-generating infection cell called an appressorium to break into rice leaves and initiate disease. Appressorium functionality is dependent on the formation of a cortical septin ring during its morphogenesis, but precisely how this structure assembles is unclear. Here, we show that F-actin rings are recruited to the circumference of incipient septin disc-like structures in a pressure-dependent manner, and that this is necessary for their contraction and remodeling into rings. We demonstrate that the structural integrity of these incipient septin discs requires both an intact F-actin and microtubule cytoskeleton and provide fundamental new insight into their functional organization within the appressorium. Lastly, using proximity-dependent labeling, we identify the actin modulator coronin as a septin-proximal protein and show that F-actin-mediated septin disc-to-ring remodeling is perturbed in the genetic absence of coronin. Taken together, our findings provide new insight into the dynamic remodeling of infection-specific higher-order septin structures in a globally significant fungal plant pathogen.
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Affiliation(s)
- Nawaraj Dulal
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA
| | - Audra Mae Rogers
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA
| | - Rinalda Proko
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA.,Cell and Molecular Biology graduate program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Baronger Dowell Bieger
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA.,Cell and Molecular Biology graduate program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Rohana Liyanage
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | | | - Yong Wang
- Cell and Molecular Biology graduate program, University of Arkansas, Fayetteville, AR 72701, USA.,Department of Physics, University of Arkansas, Fayetteville, AR 72701, USA.,Microelectronics-Photonics graduate program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Martin John Egan
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA .,Cell and Molecular Biology graduate program, University of Arkansas, Fayetteville, AR 72701, USA
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11
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Motoyama T. Secondary Metabolites of the Rice Blast Fungus Pyricularia oryzae: Biosynthesis and Biological Function. Int J Mol Sci 2020; 21:E8698. [PMID: 33218033 PMCID: PMC7698770 DOI: 10.3390/ijms21228698] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/10/2020] [Accepted: 11/17/2020] [Indexed: 02/07/2023] Open
Abstract
Plant pathogenic fungi produce a wide variety of secondary metabolites with unique and complex structures. However, most fungal secondary metabolism genes are poorly expressed under laboratory conditions. Moreover, the relationship between pathogenicity and secondary metabolites remains unclear. To activate silent gene clusters in fungi, successful approaches such as epigenetic control, promoter exchange, and heterologous expression have been reported. Pyricularia oryzae, a well-characterized plant pathogenic fungus, is the causal pathogen of rice blast disease. P. oryzae is also rich in secondary metabolism genes. However, biosynthetic genes for only four groups of secondary metabolites have been well characterized in this fungus. Biosynthetic genes for two of the four groups of secondary metabolites have been identified by activating secondary metabolism. This review focuses on the biosynthesis and roles of the four groups of secondary metabolites produced by P. oryzae. These secondary metabolites include melanin, a polyketide compound required for rice infection; pyriculols, phytotoxic polyketide compounds; nectriapyrones, antibacterial polyketide compounds produced mainly by symbiotic fungi including endophytes and plant pathogens; and tenuazonic acid, a well-known mycotoxin produced by various plant pathogenic fungi and biosynthesized by a unique NRPS-PKS enzyme.
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Affiliation(s)
- Takayuki Motoyama
- Chemical Biology Research Group, RIKEN CSRS, Wako, Saitama 351-0198, Japan
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12
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Sugahara A, Yoshimi A, Shoji F, Fujioka T, Kawai K, Umeyama H, Komatsu K, Enomoto M, Kuwahara S, Hagiwara D, Katayama T, Horiuchi H, Miyazawa K, Nakayama M, Abe K. Novel Antifungal Compound Z-705 Specifically Inhibits Protein Kinase C of Filamentous Fungi. Appl Environ Microbiol 2019; 85:e02923-18. [PMID: 30902853 PMCID: PMC6498157 DOI: 10.1128/aem.02923-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/04/2019] [Indexed: 01/17/2023] Open
Abstract
The cell wall integrity signaling (CWIS) pathway is involved in fungal cell wall biogenesis. This pathway is composed of sensor proteins, protein kinase C (PKC), and the mitogen-activated protein kinase (MAPK) pathway, and it controls the transcription of many cell wall-related genes. PKC plays a pivotal role in this pathway; deficiencies in PkcA in the model filamentous fungus Aspergillus nidulans and in MgPkc1p in the rice blast fungus Magnaporthe grisea are lethal. This suggests that PKC in filamentous fungi is a potential target for antifungal agents. In the present study, to search for MgPkc1p inhibitors, we carried out in silico screening by three-dimensional (3D) structural modeling and performed growth inhibition tests for M. grisea on agar plates. From approximately 800,000 candidate compounds, we selected Z-705 and evaluated its inhibitory activity against chimeric PKC expressed in Saccharomyces cerevisiae cells in which the kinase domain of native S. cerevisiae PKC was replaced with those of PKCs of filamentous fungi. Transcriptional analysis of MLP1, which encodes a downstream factor of PKC in S. cerevisiae, and phosphorylation analysis of the mitogen-activated protein kinase (MAPK) Mpk1p, which is activated downstream of PKC, revealed that Z-705 specifically inhibited PKCs of filamentous fungi. Moreover, the inhibitory activity of Z-705 was similar to that of a well-known PKC inhibitor, staurosporine. Interestingly, Z-705 inhibited melanization induced by cell wall stress in M. grisea We discuss the relationships between PKC and melanin biosynthesis.IMPORTANCE A candidate inhibitor of filamentous fungal protein kinase C (PKC), Z-705, was identified by in silico screening. A screening system to evaluate the effects of fungal PKC inhibitors was constructed in Saccharomyces cerevisiae Using this system, we found that Z-705 is highly selective for filamentous fungal PKC in comparison with S. cerevisiae PKC. Analysis of the AGS1 mRNA level, which is regulated by Mps1p mitogen-activated protein kinase (MAPK) via PKC, in the rice blast fungus Magnaporthe grisea revealed that Z-705 had a PKC inhibitory effect comparable to that of staurosporine. Micafungin induced hyphal melanization in M. grisea, and this melanization, which is required for pathogenicity of M. grisea, was inhibited by PKC inhibition by both Z-705 and staurosporine. The mRNA levels of 4HNR, 3HNR, and SCD1, which are essential for melanization in M. grisea, were suppressed by both PKC inhibitors.
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Affiliation(s)
- Asumi Sugahara
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Akira Yoshimi
- ABE-project, New Industry Creation Hatchery Center, Tohoku University, Sendai, Miyagi, Japan
| | - Fumio Shoji
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
| | | | | | - Hideaki Umeyama
- School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan
| | | | - Masaru Enomoto
- Laboratory of Applied Bioorganic Chemistry, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Shigefumi Kuwahara
- Laboratory of Applied Bioorganic Chemistry, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Daisuke Hagiwara
- ABE-project, New Industry Creation Hatchery Center, Tohoku University, Sendai, Miyagi, Japan
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
- Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Takuya Katayama
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Horiuchi
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan
| | - Ken Miyazawa
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Mayumi Nakayama
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
- Department of Microbial Resources, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Keietsu Abe
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, Sendai, Miyagi, Japan
- ABE-project, New Industry Creation Hatchery Center, Tohoku University, Sendai, Miyagi, Japan
- Department of Microbial Resources, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
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Motoyama T, Nogawa T, Hayashi T, Hirota H, Osada H. Induction of Nectriapyrone Biosynthesis in the Rice Blast Fungus Pyricularia oryzae
by Disturbance of the Two-Component Signal Transduction System. Chembiochem 2019; 20:693-700. [DOI: 10.1002/cbic.201800620] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Indexed: 12/12/2022]
Affiliation(s)
| | | | | | - Hiroshi Hirota
- CSRS; RIKEN; 2-1 Hirosawa Wako-shi Saitama 351-0198 Japan
| | - Hiroyuki Osada
- CSRS; RIKEN; 2-1 Hirosawa Wako-shi Saitama 351-0198 Japan
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14
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Aamir M, Singh VK, Dubey MK, Meena M, Kashyap SP, Katari SK, Upadhyay RS, Umamaheswari A, Singh S. In silico Prediction, Characterization, Molecular Docking, and Dynamic Studies on Fungal SDRs as Novel Targets for Searching Potential Fungicides Against Fusarium Wilt in Tomato. Front Pharmacol 2018; 9:1038. [PMID: 30405403 PMCID: PMC6204350 DOI: 10.3389/fphar.2018.01038] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 08/27/2018] [Indexed: 12/31/2022] Open
Abstract
Vascular wilt of tomato caused by Fusarium oxysporum f.sp. lycopersici (FOL) is one of the most devastating diseases, that delimits the tomato production worldwide. Fungal short-chain dehydrogenases/reductases (SDRs) are NADP(H) dependent oxidoreductases, having shared motifs and common functional mechanism, have been demonstrated as biochemical targets for commercial fungicides. The 1,3,6,8 tetra hydroxynaphthalene reductase (T4HNR) protein, a member of SDRs family, catalyzes the naphthol reduction reaction in fungal melanin biosynthesis. We retrieved an orthologous member of T4HNR, (complexed with NADP(H) and pyroquilon from Magnaporthe grisea) in the FOL (namely; FOXG_04696) based on homology search, percent identity and sequence similarity (93% query cover; 49% identity). The hypothetical protein FOXG_04696 (T4HNR like) had conserved T-G-X-X-X-G-X-G motif (cofactor binding site) at N-terminus, similar to M. grisea (1JA9) and Y-X-X-X-K motif, as a part of the active site, bearing homologies with two fungal keto reductases T4HNR (M. grisea) and 17-β-hydroxysteroid dehydrogenase from Curvularia lunata (teleomorph: Cochliobolus lunatus PDB ID: 3IS3). The catalytic tetrad of T4HNR was replaced with ASN115, SER141, TYR154, and LYS158 in the FOXG_04696. The structural alignment and superposition of FOXG_04696 over the template proteins (3IS3 and 1JA9) revealed minimum RMSD deviations of the C alpha atomic coordinates, and therefore, had structural conservation. The best protein model (FOXG_04696) was docked with 37 fungicides, to evaluate their binding affinities. The Glide XP and YASARA docked complexes showed discrepancies in results, for scoring and ranking the binding affinities of fungicides. The docked complexes were further refined and rescored from their docked poses through 50 ns long MD simulations, and binding free energies (ΔGbind) calculations, using MM/GBSA analysis, revealed Oxathiapiprolin and Famoxadone as better fungicides among the selected one. However, Famoxadone had better interaction of the docked residues, with best protein ligand contacts, minimum RMSD (high accuracy of the docking pose) and RMSF (structural integrity and conformational flexibility of docking) at the specified docking site. The Famoxadone was found to be acceptable based on in silico toxicity and in vitro growth inhibition assessment. We conclude that the FOXG_04696, could be employed as a novel candidate protein, for structure-based design, and screening of target fungicides against the FOL pathogen.
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Affiliation(s)
- Mohd Aamir
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Vinay Kumar Singh
- Centre for Bioinformatics, School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Manish Kumar Dubey
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Mukesh Meena
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India.,Department of Botany, University College of Science, Mohanlal Sukhadia University, Udaipur, India
| | - Sarvesh Pratap Kashyap
- Division of Crop Improvement and Biotechnology, Indian Institute of Vegetable Research, Indian Council of Agricultural Research (ICAR), Varanasi, India
| | - Sudheer Kumar Katari
- Bioinformatics Centre, Department of Bioinformatics, Sri Venkateswara Institute of Medical Sciences University, Tirupati, India
| | - Ram Sanmukh Upadhyay
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Amineni Umamaheswari
- Bioinformatics Centre, Department of Bioinformatics, Sri Venkateswara Institute of Medical Sciences University, Tirupati, India
| | - Surendra Singh
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
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Kaverinathan K, Scindiya M, Malathi P, Viswanathan R, Ramesh Sundar A. Role of Melanin in Colletotrichum falcatum Pathogenesis Causing Sugarcane Red Rot. SUGAR TECH 2017. [DOI: 10.1007/s12355-017-0519-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Lǚ Z, Kang X, Xiang Z, He N. Laccase Gene Sh-lac Is Involved in the Growth and Melanin Biosynthesis of Scleromitrula shiraiana. PHYTOPATHOLOGY 2017; 107:353-361. [PMID: 27870600 DOI: 10.1094/phyto-04-16-0180-r] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Scleromitrula shiraiana causes the popcorn disease in mulberry trees resulting in severe economic losses. Previous studies have shown that melanin may play a vital role in establishing the pathogenicity of fungi. In the present study, we identified the melanin produced in S. shiraiana belongs to DHN melanin by gas chromatography-mass spectrometry, and cloned the laccase Sh-lac, a potential DHN melanin biosynthesis gene from S. shiraiana. We obtained two stable Sh-lac silenced transformants using RNAi, ilac-4 and 8 to elucidate the DHN melanin biosynthetic pathway in S. shiraiana. The melanin production of ilac-4 and ilac-8 was significantly reduced, and their vegetative growth was also suppressed. Results such as these led to a proposal that Sh-lac played a key role in DHN melanin formation in S. shiraiana and may function differentially with other melanin biosynthetic genes. The inhibition of melanin was accompanied by the decrease of oxalic acid and the adhesion of hyphae was impaired. Our results indicated that laccase was an important enzyme in the synthesis of melanin and might play a critical role in the pathogenicity of S. shiraiana.
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Affiliation(s)
- Zhiyuan Lǚ
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Xin Kang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Zhonghuai Xiang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Ningjia He
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
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17
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Fürtges L, Conradt D, Schätzle MA, Singh SK, Kraševec N, Rižner TL, Müller M, Husain SM. Phylogenetic Studies, Gene Cluster Analysis, and Enzymatic Reaction Support Anthrahydroquinone Reduction as the Physiological Function of Fungal 17β-Hydroxysteroid Dehydrogenase. Chembiochem 2016; 18:77-80. [DOI: 10.1002/cbic.201600489] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Leon Fürtges
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
| | - David Conradt
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
| | - Michael A. Schätzle
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
- Roche Pharma AG; Emil-Barell-Strasse 1 79639 Grenzach-Wyhlen Germany
| | - Shailesh Kumar Singh
- Centre of Biomedical Research; SGPGIMS Campus; Raebareli Road, Lucknow 226014 Uttar Pradesh India
| | - Nada Kraševec
- National Institute of Chemistry; Hajdrihova 19 1000 Ljubljana Slovenia
| | - Tea Lanišnik Rižner
- Institute of Biochemistry; Faculty of Medicine; University of Ljubljana; Vrazov trg 2 1000 Ljubljana Slovenia
| | - Michael Müller
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
| | - Syed Masood Husain
- Centre of Biomedical Research; SGPGIMS Campus; Raebareli Road, Lucknow 226014 Uttar Pradesh India
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18
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Liu XH, Xu F, Snyder JH, Shi HB, Lu JP, Lin FC. Autophagy in plant pathogenic fungi. Semin Cell Dev Biol 2016; 57:128-137. [PMID: 27072489 DOI: 10.1016/j.semcdb.2016.03.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/24/2016] [Accepted: 03/29/2016] [Indexed: 11/25/2022]
Abstract
Autophagy is a conserved cellular process that degrades cytoplasmic constituents in vacuoles. Plant pathogenic fungi develop special infection structures and/or secrete a range of enzymes to invade their plant hosts. It has been demonstrated that monitoring autophagy processes can be extremely useful in visualizing the sequence of events leading to pathogenicity of plant pathogenic fungi. In this review, we introduce the molecular mechanisms involved in autophagy. In addition, we explore the relationship between autophagy and pathogenicity in plant pathogenic fungi. Finally, we discuss the various experimental strategies available for use in the study of autophagy in plant pathogenic fungi.
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Affiliation(s)
- Xiao-Hong Liu
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Fei Xu
- Institute of Digital Agriculture, Zhejiang Academy of Agricultural Science, Hangzhou, China
| | - John Hugh Snyder
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Huan-Bin Shi
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Jian-Ping Lu
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Fu-Cheng Lin
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China.
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19
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Conradt D, Schätzle MA, Husain SM, Müller M. Diversity in Reduction with Short-Chain Dehydrogenases: Tetrahydroxynaphthalene Reductase, Trihydroxynaphthalene Reductase, and Glucose Dehydrogenase. ChemCatChem 2015. [DOI: 10.1002/cctc.201500605] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- David Conradt
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
| | - Michael A. Schätzle
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
- Roche Pharma AG; Emil-Barell-Str. 1 79639 Grenzach-Wyhlen (Germany
| | - Syed Masood Husain
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
- Centre of Biomedical Research; Raebareli Road, Lucknow 226 014 Uttar Pradesh India
| | - Michael Müller
- Institut für Pharmazeutische Wissenschaften; Albert-Ludwigs-Universität Freiburg; Albertstrasse 25 79104 Freiburg Germany
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20
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Franck WL, Gokce E, Oh Y, Muddiman DC, Dean RA. Temporal analysis of the magnaporthe oryzae proteome during conidial germination and cyclic AMP (cAMP)-mediated appressorium formation. Mol Cell Proteomics 2013; 12:2249-65. [PMID: 23665591 PMCID: PMC3734583 DOI: 10.1074/mcp.m112.025874] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 04/09/2013] [Indexed: 11/06/2022] Open
Abstract
Rice blast disease caused by Magnaporthe oryzae is one of the most serious threats to global rice production. During the earliest stages of rice infection, M. oryzae conidia germinate on the leaf surface and form a specialized infection structure termed the appressorium. The development of the appressorium represents the first critical stage of infectious development. A total of 3200 unique proteins were identified by nanoLC-MS/MS in a temporal study of conidial germination and cAMP-induced appressorium formation in M. oryzae. Using spectral counting based label free quantification, observed changes in relative protein abundance during the developmental process revealed changes in the cell wall biosynthetic machinery, transport functions, and production of extracellular proteins in developing appressoria. One hundred and sixty-six up-regulated and 208 down-regulated proteins were identified in response to cAMP treatment. Proteomic analysis of a cAMP-dependent protein kinase A mutant that is compromised in the ability to form appressoria identified proteins whose developmental regulation is dependent on cAMP signaling. Selected reaction monitoring was used for absolute quantification of four regulated proteins to validate the global proteomics data and confirmed the germination or appressorium specific regulation of these proteins. Finally, a comparison of the proteome and transcriptome was performed and revealed little correlation between transcript and protein regulation. A subset of regulated proteins were identified whose transcripts show similar regulation patterns and include many of the most strongly regulated proteins indicating a central role in appressorium formation. A temporal quantitative RT-PCR analysis confirmed a strong correlation between transcript and protein abundance for some but not all genes. Collectively, the data presented here provide the first comprehensive view of the M. oryzae proteome during early infection-related development and highlight biological processes important for pathogenicity.
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Affiliation(s)
| | - Emine Gokce
- §W.M. Keck Fourier Transform-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, 27606
| | - Yeonyee Oh
- From the ‡Center for Integrated Fungal Research
| | - David C. Muddiman
- §W.M. Keck Fourier Transform-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, 27606
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Gokce E, Franck WL, Oh Y, Dean RA, Muddiman DC. In-depth analysis of the Magnaporthe oryzae conidial proteome. J Proteome Res 2012; 11:5827-35. [PMID: 23039028 PMCID: PMC3690190 DOI: 10.1021/pr300604s] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The filamentous fungus Magnaporthe oryzae (M. oryzae) is the causative agent of rice blast disease and presents a significant threat to worldwide rice production. To establish the groundwork for future research on the pathogenic development of M. oryzae, a global proteomic study of conidia was performed. The filter aided sample preparation method (FASP) and anion StageTip fractionation combined with long, optimized shallow 210 min nanoLC gradients prior to mass spectrometry analysis on an Orbitrap XL was applied, which resulted in a doubling of protein identifications in comparison to our previous GeLC analysis. Herein, we report the identification of 2912 conidial proteins at a 1% protein false discovery rate (FDR) and we present the most extensive study performed on M. oryzae conidia to date. A similar distribution between identified proteins and the predicted proteome was observed when subcellular localization analysis was performed, suggesting the detected proteins build a representative portion of the predicted proteome. A higher percentage of cytoplasmic proteins (associated with translation, energy, and metabolism) were observed in the conidial proteome relative to the whole predicted proteome. Conversely, nuclear and extracellular proteins were less well represented in the conidial proteome. Further analysis by gene ontology revealed biological insights into identified proteins important for central metabolic processes and the physiology of conidia.
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Affiliation(s)
- Emine Gokce
- W.M. Keck FT-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, 27695
| | - William L. Franck
- Center for Integrated Fungal Research, North Carolina State University, Raleigh, North Carolina, 27695
| | - Yeonyee Oh
- Center for Integrated Fungal Research, North Carolina State University, Raleigh, North Carolina, 27695
| | - Ralph A. Dean
- Center for Integrated Fungal Research, North Carolina State University, Raleigh, North Carolina, 27695
| | - David C. Muddiman
- W.M. Keck FT-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, 27695
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22
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Liu XH, Gao HM, Xu F, Lu JP, Devenish RJ, Lin FC. Autophagy vitalizes the pathogenicity of pathogenic fungi. Autophagy 2012; 8:1415-25. [PMID: 22935638 DOI: 10.4161/auto.21274] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Plant pathogenic fungi utilize a series of complex infection structures, in particular the appressorium, to gain entry to and colonize plant tissue. As a consequence of the accumulation of huge quantities of glycerol in the cell the appressorium generates immense intracellular turgor pressure allowing the penetration peg of the appressorium to penetrate the leaf cuticle. Autophagic processes are ubiquitous in eukaryotic cells and facilitate the bulk degradation of macromolecules and organelles. The study of autophagic processes has been extended from the model yeast Saccharomyces cerevisiae to pathogenic fungi such as the rice blast fungus Magnaporthe oryzae. Significantly, null mutants for the expression of M. oryzae autophagy gene homologs lose their pathogenicity for infection of host plants. Clarification of the functions and network of interactions between the proteins expressed by M. oryzae autophagy genes will lead to a better understanding of the role of autophagy in fungal pathogenesis and help in the development of new strategies for disease control.
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Affiliation(s)
- Xiao-Hong Liu
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
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23
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Schätzle MA, Husain SM, Ferlaino S, Müller M. Tautomers of Anthrahydroquinones: Enzymatic Reduction and Implications for Chrysophanol, Monodictyphenone, and Related Xanthone Biosyntheses. J Am Chem Soc 2012; 134:14742-5. [DOI: 10.1021/ja307151x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Michael A. Schätzle
- Institut
für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstr.
25, 79104 Freiburg, Germany
| | - Syed Masood Husain
- Institut
für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstr.
25, 79104 Freiburg, Germany
| | - Sascha Ferlaino
- Institut
für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstr.
25, 79104 Freiburg, Germany
| | - Michael Müller
- Institut
für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstr.
25, 79104 Freiburg, Germany
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24
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Husain SM, Schätzle MA, Röhr C, Lüdeke S, Müller M. Biomimetic Asymmetric Synthesis of (R)-GTRI-02 and (3S,4R)-3,4-Dihydroxy-3,4-dihydronaphthalen-1(2H)-ones. Org Lett 2012; 14:3600-3. [DOI: 10.1021/ol301305p] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Syed Masood Husain
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University of Freiburg, Albertstrasse 25, 79104 Freiburg, Germany, and Institute for Inorganic and Analytical Chemistry, Albert-Ludwigs-University of Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Michael A. Schätzle
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University of Freiburg, Albertstrasse 25, 79104 Freiburg, Germany, and Institute for Inorganic and Analytical Chemistry, Albert-Ludwigs-University of Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Caroline Röhr
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University of Freiburg, Albertstrasse 25, 79104 Freiburg, Germany, and Institute for Inorganic and Analytical Chemistry, Albert-Ludwigs-University of Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Steffen Lüdeke
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University of Freiburg, Albertstrasse 25, 79104 Freiburg, Germany, and Institute for Inorganic and Analytical Chemistry, Albert-Ludwigs-University of Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Michael Müller
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University of Freiburg, Albertstrasse 25, 79104 Freiburg, Germany, and Institute for Inorganic and Analytical Chemistry, Albert-Ludwigs-University of Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
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25
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Schätzle MA, Flemming S, Husain SM, Richter M, Günther S, Müller M. Tetrahydroxynaphthalene Reductase: Catalytic Properties of an Enzyme Involved in Reductive Asymmetric Naphthol Dearomatization. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201107695] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Schätzle MA, Flemming S, Husain SM, Richter M, Günther S, Müller M. Tetrahydroxynaphthalene Reductase: Catalytic Properties of an Enzyme Involved in Reductive Asymmetric Naphthol Dearomatization. Angew Chem Int Ed Engl 2012; 51:2643-6. [DOI: 10.1002/anie.201107695] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Indexed: 11/08/2022]
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Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses. BMC Genomics 2011; 12:49. [PMID: 21247492 PMCID: PMC3037901 DOI: 10.1186/1471-2164-12-49] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 01/19/2011] [Indexed: 01/13/2023] Open
Abstract
Background Rice blast is the most threatening disease to cultivated rice. Magnaporthe oryzae, its causal agent, is likely to encounter environmental challenges during invasive growth in its host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that gene expression patterns during in planta invasive growth are similar to in vitro stress conditions, such as nutrient limitation, temperature up shift and oxidative stress, and determined which condition most closely mimicked that of in planta invasive growth. Gene expression data were collected from these in vitro experiments and compared to fungal gene expression during the invasive growth phase at 72 hours post-inoculation in compatible interactions on two grass hosts, rice and barley. Results We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference. From those genes, 1,909 showed similar expression patterns between at least one of the in vitro stresses and rice and/or barley. Hierarchical clustering of these 1,909 genes showed three major clusters in which in planta conditions closely grouped with the nutrient starvation conditions. Out of these 1,909 genes, 55 genes and 129 genes were induced and repressed in all treatments, respectively. Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions. The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport. Conclusions These findings suggest that M. oryzae is likely primarily coping with nutrient-limited environments at the invasive growth stage 72 hours post-inoculation, and not with oxidative or temperature stresses.
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Takano Y, Kubo Y, Kuroda I, Furusawa I. Temporal Transcriptional Pattern of Three Melanin Biosynthesis Genes, PKS1, SCD1, and THR1, in Appressorium-Differentiating and Nondifferentiating Conidia of Colletotrichum lagenarium. Appl Environ Microbiol 2010; 63:351-4. [PMID: 16535499 PMCID: PMC1389113 DOI: 10.1128/aem.63.1.351-354.1997] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A phytopathogenic fungus, Colletotrichum lagenarium, produces melanized appressoria that display temperature-sensitive differentiation. Conidia incubated in water at 24(deg)C germinated, and germ tubes differentiated into melanized appressoria. On the other hand, conidia incubated in water at 32(deg)C germinated and produced germ tubes that elongated without appressorium differentiation. Conidia in 0.1% yeast extract solution at 32(deg)C germinated and developed into vegetative hyphae. In this study, we investigated the temporal transcriptional pattern of cloned melanin biosynthesis genes, PKS1, SCD1, and THR1, in these differentiating and nondifferentiating conidia. During appressorium differentiation, de novo transcripts of the three melanin biosynthesis genes accumulated 1 to 2 h after the start of conidial incubation at 24(deg)C, and the amount of transcripts began to decrease at 6 h. In conidia germinating in water at 32(deg)C, the transcriptional pattern of the PKS1, SCD1, and THR1 genes was similar to that of these genes in appressorium-forming conidia, although no appressoria were formed. However, in conidia in 0.1% yeast extract solution at 32(deg)C, transcripts of the three melanin biosynthesis genes hardly accumulated.
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Cary JW, Ehrlich KC. Aflatoxigenicity in Aspergillus: molecular genetics, phylogenetic relationships and evolutionary implications. Mycopathologia 2006; 162:167-77. [PMID: 16944284 DOI: 10.1007/s11046-006-0051-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Aflatoxins (AFs) are toxic and carcinogenic secondary metabolites produced by isolates of Aspergillus section Flavi as well as a number of Aspergillus isolates that are classified outside of section Flavi. Characterization of the AF and sterigmatocystin (ST) gene clusters and analysis of factors governing regulation of their biosynthesis has resulted in these two mycotoxins being the most extensively studied of fungal secondary metabolites. This wealth of information has allowed the determination of the molecular basis for non-production of AF in natural isolates of A. flavus and domesticated strains of A. oryzae. This review provides an overview of the molecular analysis of the AF and ST gene clusters as well as new information on an AF gene cluster identified in the non-section Flavi isolate, Aspergillus ochraceoroseus. Additionally, molecular phylogenetic analysis using AF biosynthetic gene sequences as well as ribosomal DNA internal transcribed spacer (ITS) sequences between various section Flavi and non-section Flavi species has enabled determination of the probable evolutionary history of the AF and ST gene clusters. A model for the evolution of the AF and ST gene clusters as well as possible biological roles for AF are discussed.
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Affiliation(s)
- Jeffrey W Cary
- USDA, ARS, Southern Regional Research Center, 1100 Robert E. Lee Blvd., New Orleans, LA 70124, USA.
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Hadj-Hamdri A, Vidal-Cros A, Gaudry M, Sobrio F, Rousseau B. Synthesis of high specific radioactivity [3H]emodin. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580360811] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Cary JW, Ehrlich KC, Bland JM, Montalbano BG. The aflatoxin biosynthesis cluster gene, aflX, encodes an oxidoreductase involved in conversion of versicolorin A to demethylsterigmatocystin. Appl Environ Microbiol 2006; 72:1096-101. [PMID: 16461654 PMCID: PMC1392920 DOI: 10.1128/aem.72.2.1096-1101.2006] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biosynthesis of the toxic and carcinogenic aflatoxins by the fungus Aspergillus flavus is a complicated process involving more that 27 enzymes and regulatory factors encoded by a clustered group of genes. Previous studies found that three enzymes, encoded by verA, ver-1, and aflY, are required for conversion of versicolorin A (VA), to demethylsterigmatocystin. We now show that a fourth enzyme, encoded by the previously uncharacterized gene, aflX (ordB), is also required for this conversion. A homolog of this gene, stcQ, is present in the A. nidulans sterigmatocystin (ST) biosynthesis cluster. Disruption of aflX in Aspergillus flavus gave transformants that accumulated approximately 4-fold more VA and fourfold less aflatoxin than the untransformed strain. Southern and Northern blot analyses confirmed that aflX was the only gene disrupted in these transformants. Feeding ST or O-methylsterigmatocystin, but not VA or earlier precursor metabolites, restored normal levels of AF production. The protein encoded by aflX is predicted to have domains typical of an NADH-dependent oxidoreductase. It has 27% amino acid identity to a protein encoded by the aflatoxin cluster gene, aflO (avfA). Some of domains in the protein are similar to those of epoxide hydrolases.
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Affiliation(s)
- Jeffrey W Cary
- Southern Regional Research Center/ARS/USDA, P.O. Box 19687, New Orleans, LA 70179, USA.
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Abstract
AIMS To compare the biosynthetic gene cluster sequences of the main aflatoxin (AF)-producing Aspergillus species. METHODS AND RESULTS Sequencing was on fosmid clones selected by homology to Aspergillus parasiticus sequence. Alignments revealed that gene order is conserved among AF gene clusters of Aspergillus nomius, A. parasiticus, two sclerotial morphotypes of Aspergillus flavus, and an unnamed Aspergillus sp. Phylogenetic relationships were established using the maximum likelihood method implemented in PAUP. Based on the Eurotiomycete/Sordariomycete divergence time, the A. flavus-type cluster has been maintained for at least 25 million years. Such conservation of the genes and gene order reflects strong selective constraints on rearrangement. Phylogenetic comparison of individual genes in the cluster indicated that ver-1, which has homology to a melanin biosynthesis gene, experienced selective forces distinct from the other pathway genes. Sequences upstream of the polyketide synthase-encoding gene vary among the species, but a four-gene sugar utilization cluster at the distal end is conserved, indicating a functional relationship between the two adjacent clusters. CONCLUSIONS The high conservation of cluster components needed for AF production suggests there is an adaptive value for AFs in character-shaping niches important to those taxa. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first comparison of the complete nucleotide sequences of gene clusters harbouring the AF biosynthesis genes of the main AF-producing species. Such a comparison will aid in understanding how AF biosynthesis is regulated in experimental and natural environments.
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Affiliation(s)
- K C Ehrlich
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, 1100 Robert E. Lee Boulevard, PO Box 19687, New Orleans, LA 70179, USA.
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Ehrlich KC, Montalbano B, Boué SM, Bhatnagar D. An aflatoxin biosynthesis cluster gene encodes a novel oxidase required for conversion of versicolorin a to sterigmatocystin. Appl Environ Microbiol 2006; 71:8963-5. [PMID: 16332900 PMCID: PMC1317430 DOI: 10.1128/aem.71.12.8963-8965.2005] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Disruption of the aflatoxin biosynthesis cluster gene aflY (hypA) gave Aspergillus parasiticus transformants that accumulated versicolorin A. This gene is predicted to encode the Baeyer-Villiger oxidase necessary for formation of the xanthone ring of the aflatoxin precursor demethylsterigmatocystin.
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Affiliation(s)
- Kenneth C Ehrlich
- SRRC/ARS/USDA, 1100 R. E. Lee Blvd., P.O. Box 19687, New Orleans, LA 70179, USA.
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Brakhage AA, Liebmann B. Aspergillus fumigatus conidial pigment and cAMP signal transduction: significance for virulence. Med Mycol 2005; 43 Suppl 1:S75-82. [PMID: 16110796 DOI: 10.1080/13693780400028967] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The conidial pigment of Aspergillus fumigatus contains 1,8-dihydroxynaphthalene (DHN)-like pentaketide melanin. It plays a major role in the protection of the fungus against immune effector cells; for example, it is able to scavenge reactive oxygen species generated by alveolar macrophages and neutrophiles. The polyketide synthase PKSP (ALB1) is a key-enzyme of the biosynthesis pathway; its structural gene is part of a gene cluster. Furthermore, the presence of a functional pksP (albl) gene in A. fumigatus conidia is associated with an inhibition of phagolysosome fusion in human monocyte-derived macrophages. Moreover, the analysis of mutants that are defective in elements of the cAMP signaling pathway found that they are almost avirulent in an optimized low dose murine inhalation model. Taken together, our results indicate that the cAMP/PKA signal transduction pathway is required for A. fumigatus pathogenicity. In addition, we showed that the expression of the pksP gene is, at least in part, controlled by the cAMP/ PKA signal transduction pathway. Currently, we hypothesize that pentaketide melanin is important for defence against ROS. However, besides its contribution to the biosynthesis of DHN-like melanin, PKSP also appears to be involved in the formation of another compound which is immunosuppressive.
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Affiliation(s)
- A A Brakhage
- Leibniz-lnstitute for Natural Products Research and Infection Biology-Hans-Knoell-lnstitute, Department of Molecular and Applied Microbiology, Jena, Germany.
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Lu JP, Liu TB, Lin FC. Identification of mature appressorium-enriched transcripts in Magnaporthe grisea, the rice blast fungus, using suppression subtractive hybridization. FEMS Microbiol Lett 2005; 245:131-7. [PMID: 15796990 DOI: 10.1016/j.femsle.2005.02.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2004] [Revised: 01/07/2005] [Accepted: 02/28/2005] [Indexed: 10/25/2022] Open
Abstract
We have constructed a fungal subtractive suppressive library enriched in genes expressed during appressorium maturation in Magnaporthe grisea. Sequencing of 250 clones from the subtracted appressorium cDNA library revealed 142 unique genes, represented by 155 non-redundant ESTs (expressed sequence tags). Of these ESTs, 72 have not been previously isolated in M. grisea. RT-PCR analysis of 105 of the genes discovered found transcripts corresponding to 71 of the ESTs only in mature appressoria while transcripts corresponding to a further 34 of the isolated ESTs were expressed both in appressoria and conidia/mycelia. Genes specifically expressed in appressorium identified by SSH included a number that have been previously implicated in appressorium formation or function including GAS1, GAS3, and PTH11.
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Affiliation(s)
- Jian-Ping Lu
- College of Life Sciences, Zhejiang University, Kaixuan Road 268, Hangzhou 310029, PR China
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36
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Fitzgerald A, Van Kan JAL, Plummer KM. Simultaneous silencing of multiple genes in the apple scab fungus, Venturia inaequalis, by expression of RNA with chimeric inverted repeats. Fungal Genet Biol 2004; 41:963-71. [PMID: 15341918 DOI: 10.1016/j.fgb.2004.06.006] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2004] [Accepted: 06/28/2004] [Indexed: 11/24/2022]
Abstract
RNA-mediated gene silencing has been demonstrated in plants, animals, and more recently in filamentous fungi. Here, we report high frequency, RNA-mediated gene silencing in the apple scab fungus, Venturia inaequalis. The green fluorescent protein (GFP) transgene was silenced in a GFP-expressing transformant. An endogenous gene, trihydroxynaphthalene reductase (THN), involved in melanin biosynthesis, was also silenced. Silencing of these two genes resulted in obvious phenotypes in vitro. High frequency gene silencing was achieved using hairpin constructs for the GFP or the THN genes transferred by Agrobacterium (71 and 61%, respectively). THN-silenced transformants exhibited a distinctive light brown phenotype and maintained the ability to infect apple. Of significance was the simultaneous silencing of the two genes from a single chimeric, inverted repeat hairpin construct. Silencing of both genes with this construct occurred at a frequency of 51% of all the transformants. All 125 colonies silenced for the GFP gene were also silenced for THN. As THN and GFP silenced transformants have readily detectable phenotypes, the genes have utility as markers for gene silencing. Simultaneous, multiple gene silencing, utilising such marker genes, will enable the development of high through-put screening for functional genomics. This chimeric technology will be particularly valuable when linked with silenced genes that have no obvious phenotype in vitro.
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Affiliation(s)
- Anna Fitzgerald
- Plant Health and Development, Horticulture and Food Research Institute of New Zealand Ltd., Auckland, New Zealand
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Kihara J, Moriwaki A, Ito M, Arase S, Honda Y. Expression of THR1, a 1,3,8-Trihydroxynaphthalene Reductase Gene Involved in Melanin Biosynthesis in the Phytopathogenic Fungus Bipolaris oryzae, is Enhanced by Near-Ultraviolet Radiation. ACTA ACUST UNITED AC 2004; 17:15-23. [PMID: 14717841 DOI: 10.1046/j.1600-0749.2003.00102.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1,3,8-Trihydroxynaphthalene (1,3,8-THN) reductase is involved in the production of fungal dihydroxynaphthalene (DHN) melanin. We isolated and characterized THR1, a gene encoding 1,3,8-THN reductase, from the phytopathogenic fungus Bipolaris oryzae. Sequence analysis showed that THR1 encodes a putative protein of 267 amino acids having a molecular weight of 28.5 kDa and 68-98% sequence identity to other fungal 1,3,8-THN reductases. Targeted disruption of the THR1 gene showed that it is essential for melanin biosynthesis in B. oryzae. Northern blot analysis showed that THR1 transcripts are constitutively expressed during normal growth but are specifically enhanced by near-ultraviolet (NUV) radiation in a dose-dependent manner. These results indicate that THR1 expression is transcriptionally enhanced by NUV radiation in B. oryzae.
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Affiliation(s)
- Junichi Kihara
- Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan.
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Irie T, Matsumura H, Terauchi R, Saitoh H. Serial Analysis of Gene Expression (SAGE) of Magnaporthe grisea: genes involved in appressorium formation. Mol Genet Genomics 2003; 270:181-9. [PMID: 12955499 DOI: 10.1007/s00438-003-0911-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2003] [Accepted: 07/28/2003] [Indexed: 11/27/2022]
Abstract
Treatment with cyclic AMP (cAMP) induces appressorium formation in the phytopathogenic fungus Magnaporthe grisea, the causative agent of rice blast disease. In a search for the M. grisea genes responsible for appressorium formation and host invasion, SAGE (Serial Analysis of Gene Expression) was carried out using mRNA isolated from fungal conidia germinating in the presence and absence of cAMP. From cAMP-treated conidia 5087 tags including 2889 unique tags were isolated, whereas untreated conidia yielded 2342 unique tags out of total of 3938. cAMP treatment resulted in up- and down-regulation of genes corresponding to 57 and 53 unique tags, respectively. Upon consultation of EST/cDNA databases, 22 tags with higher representation in cAMP-treated conidia were annotated with putative gene names. Furthermore, 28 tags corresponding to cAMP-induced genes could be annotated with the help of the recently published genome sequence of M. grisea. cAMP-induced genes identified by SAGE included many genes that have not been described so far, as well as a number of genes known to be involved in pathogenicity, e.g. MPG1, MAS1 and MAC1. RT-PCR of 13 randomly selected genes confirmed the SAGE results, verifying the fidelity of the SAGE data.
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Affiliation(s)
- T Irie
- Department of Environmental Science, University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga 522-8533, Japan
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Tsuji G, Sugahara T, Fujii I, Mori Y, Ebizuka Y, Shiraishi T, Kubo Y. Evidence for involvement of two naphthol reductases in the first reduction step of melanin biosynthesis pathway of Colletotrichum lagenarium. MYCOLOGICAL RESEARCH 2003; 107:854-60. [PMID: 12967213 DOI: 10.1017/s0953756203008001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Colletotrichum lagenarium is a plant pathogenic fungus, and produces melanin that is an essential factor for appressorial penetration into host tissues. The melanin biosynthesis pathway of C. lagenarium starts with pentaketide synthesis catalyzed by polyketide synthase Pks1p. We previously confirmed that the direct product of Pks1p is 1,3,6,8-tetrahydroxynaphthalene. Thus, melanin biosynthesis in this fungus requires the reduction of 1,3,6,8-tetrahydroxynaphthalene to scytalone. We made a double mutant 9141-144 from the thr1 mutant 9141 that lacks the ability to metabolize 1,3,8-trihydroxynaphthalene. The double mutant 9141-144 could metabolize neither 1,3,6,8-tetrahydroxynaphthalene nor 1,3,8-trihydroxynaphthalene. However melanin production by the double mutant was restored by THR1, indicating that Thr1p can metabolize both compounds in vivo. These results demonstrate that two enzymes, Thr1p and a deduced 1,3,6,8-tetrahydroxynaphthalene-specific reductase, are involved in the first reduction step of the melanin biosynthesis pathway of C. lagenarium.
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Affiliation(s)
- Gento Tsuji
- Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto Prefectural University, Kyoto 606-8522, Japan
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Langfelder K, Streibel M, Jahn B, Haase G, Brakhage AA. Biosynthesis of fungal melanins and their importance for human pathogenic fungi. Fungal Genet Biol 2003; 38:143-58. [PMID: 12620252 DOI: 10.1016/s1087-1845(02)00526-1] [Citation(s) in RCA: 409] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
For more than 40 years fungi have been known to produce pigments known as melanins. Predominantly these have been dihydroxyphenylalanine (DOPA)-melanin and dihydroxynaphthalene (DHN)-melanin. The biochemical and genetical analysis of the biosynthesis pathways have led to the identification of the genes and corresponding enzymes of the pathways. Only recently have both these types of melanin been linked to virulence in some human pathogenic and phytopathogenic fungi. The absence of melanin in human pathogenic and phytopathogenic fungi often leads to a decrease in virulence. In phytopathogenic fungi such as Magnaporthe grisea and Colletotrichum lagenarium, besides other possible functions in pathogenicity, DHN-melanin plays an essential role in generating turgor for plant appressoria to penetrate plant leaves. While the function of melanin in human pathogenic fungi such as Cryptococcus neoformans, Wangiella dermatitidis, Sporothrix schenckii, and Aspergillus fumigatus is less well defined, its role in protecting fungal cells has clearly been shown. Specifically, the ability of both DOPA- and DHN-melanins to quench free radicals is thought to be an important factor in virulence. In addition, in several fungi the production of fungal virulence factors, such as melanin, has been linked to a cAMP-dependent signaling pathway. Many of the components involved in the signaling pathway have been identified.
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Affiliation(s)
- Kim Langfelder
- Institut für Mikrobiologie, Universität Hannover, Schneiderberg 50, 30167, Hannover, Germany
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Inhibitors and genetic analysis of scytalone dehydratase confirm the presence of DHN-melanin pathway in sapstain fungi. ACTA ACUST UNITED AC 2002. [DOI: 10.1017/s0953756202006664] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Chang PK, Bennett JW, Cotty PJ. Association of aflatoxin biosynthesis and sclerotial development in Aspergillus parasiticus. Mycopathologia 2002; 153:41-8. [PMID: 11913765 DOI: 10.1023/a:1015211915310] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Secondary metabolism in fungi is frequently associated with asexual and sexual development. Aspergillus parasiticus produces aflatoxins known to contaminate a variety of agricultural commodities. This strictly mitotic fungus. besides producing conidia asexually, produces sclerotia, structures resistant to harsh conditions and for propagation. Sclerotia are considered to be derived from the sexual structure, cleistothecia. and may represent a vestige of ascospore production. Introduction of the aflatoxin pathway-specific regulatory gene, aflR, and aflJ, which encoded a putative co-activator, into an O-methylsterigmatocystin (OMST)-accumulating strain, A. parasiticus SRRC 2043, resulted in elevated levels of accumulation of major aflatoxin precursors, including norsolorinic acid (NOR), averantin (AVN), versicolorin A (VERA) and OMST. The total amount of these aflatoxin precursors, NOR, VERA, AVN and OMST, produced by the aflR plus aflJ transformants was two to three-fold that produced by the aflR transformants. This increase indicated a synergistic effect of aflR and aflJ on the synthesis of aflatoxin precursors. Increased production of the aflatoxin precursors was associated with progressive decrease in sclerotial size, alteration in sclerotial shape and weakening in the sclerotial structure of the transformants. The results showed that sclerotial development and aflatoxin biosynthesis are closely related. We proposed that competition for a common substrate, such as acetate, by the aflatoxin biosynthetic pathway could adversely affect sclerotial development in A. parasiticus.
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Affiliation(s)
- Perng-Kuang Chang
- Southern Regional Research Center, Agricultural Research Service, US Department of Agriculture, New Orleans, Louisiana 70124, USA.
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Farman ML. Meiotic deletion at the BUF1 locus of the fungus Magnaporthe grisea is controlled by interaction with the homologous chromosome. Genetics 2002; 160:137-48. [PMID: 11805051 PMCID: PMC1461934 DOI: 10.1093/genetics/160.1.137] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Magnaporthe grisea BUF1 gene suffers high-frequency mutation in certain genetic crosses, resulting in buff-colored progeny. Analysis of 16 buf1 mutants arising from a cross with a mutation frequency of 25% revealed that, in every case, the BUF1 gene was deleted. The deletions occurred in only one of the parental chromosomes and were due to intrachromosomal recombination. Tetrad analysis revealed that deletions occurred in 44% of meioses and usually affected both chromatids of the mutable chromosome. This suggests that they happen before the premeiotic round of DNA synthesis. However, they were also almost entirely restricted to heteroallelic crosses. This, together with the discovery of numerous repetitive elements that were present only in the mutable BUF1 locus, suggests that the deletion process is sensitive to pairing interactions between homologous chromosomes, such that only unpaired loci are subject to deletion. Given that karyogamy is not supposed to occur until after premeiotic DNA replication in Pyrenomycetous fungi such as M. grisea, this latter observation would place the time of deletion during, or after, DNA synthesis. These conflicting results suggest that karyogamy might actually precede DNA replication in Pyrenomycetous fungi or that parts of the genome remain unreplicated until after karyogamy and subsequent chromosome pairing have taken place.
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Affiliation(s)
- Mark L Farman
- Department of Plant Pathology, University of Kentucky, Lexington, Kentucky 40546, USA.
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Su JH, Chuang YC, Tsai YC, Chang MC. Cloning and characterization of a blue fluorescent protein from Vibrio vulnificus. Biochem Biophys Res Commun 2001; 287:359-65. [PMID: 11554735 DOI: 10.1006/bbrc.2001.5590] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The blue fluorescent protein (BFPVV) gene bfpvv from Vibrio vulnificus CKM-1 was cloned and sequenced. The transformants exhibited blue fluorescence when irradiated by UV source. Nucleotide sequence analysis predicted an ORF of 717 bp encoding a 239-amino-acid polypeptide with a calculated molecular mass of 25.8 kDa. The nucleotide sequence of the bfpvv gene and its deduced amino acid sequence showed significant homology to those of the short-chain dehydrogenase/reductase (SDR) family proteins from various organisms. Some functionally important residues in SDR were strictly conserved in BFPVV, such as an active-site Tyr145, a catalytic site Lys149, and a common GlyXXXGlyXGly pattern in the N-terminal part of the molecule. By changing three amino acid residues, Tyr145, Lys149, and Gly9 to Phe, Ile, and Val, respectively, it was found that the G9V mutant did not generate blue fluorescence, while mutants Y145F and K149I have 126 and 68.5% fluorescence compared with the wild-type BFPVV.
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Affiliation(s)
- J H Su
- Department of Industrial Safety and Hygiene, Chia-Nan University of Pharmacy and Science, Tainan, Republic of China
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Abstract
Summary Recently many fungal genes have been identified that, when disrupted, result in strains with a reduction or total loss of disease symptoms. Such pathogenicity genes are the subject of this review. The large number of pathogenicity genes identified is due to the application of tagged mutagenesis techniques (random or targeted). Genes have been identified with roles in the formation of infection structures, cell wall degradation, overcoming or avoiding plant defences, responding to the host environment, production of toxins, and in signal cascades. Additionally, genes with no database matches and with 'novel' functions have also been found. Improved technologies for mutation analysis and for sequencing and analysing fungal genomes hold promise for identifying many more pathogenicity genes.
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Affiliation(s)
- A Idnurm
- School of Botany, The University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
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46
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An hydroxynaphtalene reductase gene from the wood-staining fungus Ophiostoma floccosum complements the buff phenotype in Magnaporthe grisea. ACTA ACUST UNITED AC 2001. [DOI: 10.1017/s0953756201003744] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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47
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Feng B, Wang X, Hauser M, Kaufmann S, Jentsch S, Haase G, Becker JM, Szaniszlo PJ. Molecular cloning and characterization of WdPKS1, a gene involved in dihydroxynaphthalene melanin biosynthesis and virulence in Wangiella (Exophiala) dermatitidis. Infect Immun 2001; 69:1781-94. [PMID: 11179356 PMCID: PMC98085 DOI: 10.1128/iai.69.3.1781-1794.2001] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
1,8-Dihydroxynaphthalene (1,8-DHN) is a fungal polyketide that contributes to virulence when polymerized to 1,8-DHN melanin in the cell walls of Wangiella dermatitidis, an agent of phaeohyphomycosis in humans. To begin a genetic analysis of the initial synthetic steps leading to 1,8-DHN melanin biosynthesis, a 772-bp PCR product was amplified from genomic DNA using primers based on conserved regions of fungal polyketide synthases (Pks) known to produce the first cyclized 1,8-DHN-melanin pathway intermediate, 1,3,6,8-tetrahydroxynaphthalene. The cloned PCR product was then used as a targeting sequence to disrupt the putative polyketide synthase gene, WdPKS1, in W. dermatitidis. The resulting wdpks1Delta disruptants showed no morphological defects other than an albino phenotype and grew at the same rate as their black wild-type parent. Using a marker rescue approach, the intact WdPKS1 gene was then successfully recovered from two plasmids. The WdPKS1 gene was also isolated independently by complementation of the mel3 mutation in an albino mutant of W. dermatitidis using a cosmid library. Sequence analysis substantiated that WdPKS1 encoded a putative polyketide synthase (WdPks1p) in a single open reading frame consisting of three exons separated by two short introns. This conclusion was supported by the identification of highly conserved Pks domains for a beta-ketoacyl synthase, an acetyl-malonyl transferase, two acyl carrier proteins, and a thioesterase in the deduced amino acid sequence. Studies using a neutrophil killing assay and a mouse acute-infection model confirmed that all wdpks1Delta strains were less resistant to killing and less virulent, respectively, than their wild-type parent. Reconstitution of 1,8-DHN melanin biosynthesis in a wdpks1Delta strain reestablished its resistance to killing by neutrophils and its ability to cause fatal mouse infections.
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Affiliation(s)
- B Feng
- Section of Molecular Genetics and Microbiology, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
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48
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Ichinose K, Ebizuka Y, Sankawa U. Mechanistic studies on the biomimetic reduction of tetrahydroxynaphthalene, a key intermediate in melanin biosynthesis. Chem Pharm Bull (Tokyo) 2001; 49:192-6. [PMID: 11217108 DOI: 10.1248/cpb.49.192] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
1,3,6,8-Tetrahydroxynaphthalene (T4HN) is an aromatic polyketide, serving as a general precursor of fungal melanin. Melanin biosynthesis involves two consecutive deoxygenations of T4HN, consisting of the reduction of a phenolic carbon followed by dehydration. The first reduction to produce scytalone was studied in a biomimetic reduction with sodium borohydride. The reduction required a strong alkaline condition, leading to the tautomerization of T4HN to a reactive species whose structure was clarified by NMR spectroscopy.
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Affiliation(s)
- K Ichinose
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan
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49
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Clustered metabolic pathway genes in filamentous fungi. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s1874-5334(01)80009-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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50
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Thompson JE, Fahnestock S, Farrall L, Liao DI, Valent B, Jordan DB. The second naphthol reductase of fungal melanin biosynthesis in Magnaporthe grisea: tetrahydroxynaphthalene reductase. J Biol Chem 2000; 275:34867-72. [PMID: 10956664 DOI: 10.1074/jbc.m006659200] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutants of Magnaporthe grisea harboring a defective gene for 1,3, 8-trihydroxynaphthalene reductase retain the capability to produce scytalone, thus suggesting the existence of a second naphthol reductase that can catalyze the reduction of 1,3,6, 8-tetrahydroxynaphthalene to scytalone within the fungal melanin biosynthetic pathway. The second naphthol reductase gene was cloned from M. grisea by identification of cDNA fragments with weak homology to the cDNA of trihydroxynaphthalene reductase. The amino acid sequence for the second naphthol reductase is 46% identical to that of trihydroxynaphthalene reductase. The second naphthol reductase was produced in Esherichia coli and purified to homogeneity. Substrate competition experiments indicate that the second reductase prefers tetrahydroxynaphthalene over trihydroxynaphthalene by a factor of 310; trihydroxynaphthalene reductase prefers trihydroxynaphthalene over tetrahydroxynaphthalene by a factor of 4.2. On the basis of the 1300-fold difference in substrate specificities between the two reductases, the second reductase is designated tetrahydroxynaphthalene reductase. Tetrahydroxynaphthalene reductase has a 200-fold larger K(i) for the fungicide tricyclazole than that of trihydroxynaphthalene reductase, and this accounts for the latter enzyme being the primary physiological target of the fungicide. M. grisea mutants lacking activities for both trihydroxynaphthalene and tetrahydroxynaphthalene reductases do not produce scytalone, indicating that there are no other metabolic routes to scytalone.
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Affiliation(s)
- J E Thompson
- DuPont Agricultural Products, Stine-Haskell Research Center, Newark, Delaware 19714, USA
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