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Li W, Li P, Zhou X, Situ J, Lin Y, Qiu J, Yuan Y, Xi P, Jiang Z, Kong G. A Cytochrome B 5-Like Heme/Steroid Binding Domain Protein, PlCB5L1, Regulates Mycelial Growth, Pathogenicity and Oxidative Stress Tolerance in Peronophythora litchii. FRONTIERS IN PLANT SCIENCE 2021; 12:783438. [PMID: 34899811 PMCID: PMC8655872 DOI: 10.3389/fpls.2021.783438] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 11/01/2021] [Indexed: 06/14/2023]
Abstract
As an electron transport component, cytochrome b5 is an essential component of the Class II cytochrome P450 monooxygenation system and widely present in animals, plants, and fungi. However, the roles of Cyt-b5 domain proteins in pathogenic oomycetes remain unknown. Peronophythora litchii is an oomycete pathogen that causes litchi downy blight, the most destructive disease of litchi. In this study, we identified a gene, designated PlCB5L1, that encodes a Cyt-b5 domain protein in P. litchii, and characterized its function. PlCB5L1 is highly expressed in the zoospores, cysts, germinated cysts, and during early stages of infection. PlCB5L1 knockout mutants showed reduced growth rate and β-sitosterol utilization. Importantly, we also found that PlCB5L1 is required for the full pathogenicity of P. litchii. Compared with the wild-type strain, the PlCB5L1 mutants exhibited significantly higher tolerance to SDS and sorbitol, but impaired tolerance to cell wall stress, osmotic stress, and oxidative stress. Further, the expression of genes involved in oxidative stress tolerance, including peroxidase, cytochrome P450, and laccase genes, were down-regulated in PlCB5L1 mutants under oxidative stress. This is the first report that a Cyt-b5 domain protein contributes to the development, stress response, and pathogenicity in plant pathogenic oomycetes.
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Affiliation(s)
- Wen Li
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Peng Li
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Xiaofan Zhou
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Junjian Situ
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Yiming Lin
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Jiahui Qiu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Yuling Yuan
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Pinggen Xi
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Zide Jiang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
| | - Guanghui Kong
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou, China
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Sphingolipids in foodstuff: Compositions, distribution, digestion, metabolism and health effects - A comprehensive review. Food Res Int 2021; 147:110566. [PMID: 34399542 DOI: 10.1016/j.foodres.2021.110566] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 12/26/2022]
Abstract
Sphingolipids (SLs) are common in all eukaryotes, prokaryotes, and viruses, and played a vital role in human health. They are involved in physiological processes, including intracellular transport, cell division, and signal transduction. However, there are limited reviews on dietary effects on endogenous SLs metabolism and further on human health. Various dietary conditions, including the SLs-enriched diet, high-fat diet, and vitamins, can change the level of endogenous SLs metabolites and even affect human health. This review systematically summarizes the main known SLs in foods concerning their variety and contents, as well as their isolation and identification approaches. Moreover, the present review discusses the role of dietary (particularly SLs-enriched diet, high-fat diet, and vitamins) in endogenous SLs metabolism, highlighting how exogenous SLs are digested and absorbed. The role of SLs family in the pathogenesis of diseases, including cancers, neurological disorders, infectious and inflammatory diseases, and cardiovascular diseases, and in recently coronavirus disease-19 outbreak was also discussed. In the post-epidemic era, we believe that the concern for health and the need for plant-based products will increase. Therefore, a need for research on the absorption and metabolism pathway of SLs (especially plant-derived SLs) and their bioavailability is necessary. Moreover, the effects of storage treatment and processing on the content and composition of SLs in food are worth exploring. Further studies should also be conducted on the dose-response of SLs on human health to support the development of SLs supplements. More importantly, new approaches, such as, making SLs based hydrogels can effectively achieve sustained release and targeted therapies.
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Hartmann DO, Piontkivska D, Moreira CJS, Silva Pereira C. Ionic Liquids Chemical Stress Triggers Sphingoid Base Accumulation in Aspergillus nidulans. Front Microbiol 2019; 10:864. [PMID: 31105664 PMCID: PMC6491925 DOI: 10.3389/fmicb.2019.00864] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 04/04/2019] [Indexed: 11/30/2022] Open
Abstract
Understanding stress responses and signaling pathways in fungi became a fundamental need for the discovery of new specific antifungal targets for fighting emerging life-threatening pathogens and drug resistance. Ionic liquids constitute a unique class of chemicals, which structural diversity and tunable physical and chemical properties can provide a great diversity of stimuli. In this study, we propose the use of ionic liquids as tools to unravel signaling of stress responses in the filamentous fungus Aspergillus nidulans. We assessed how three ionic liquids with distinct effects over the cell wall and plasma membrane affect the biosynthesis of sphingolipids and accumulation of free sphingoid bases in this fungus. The stress imposed by each ionic liquid triggered the sphingolipid biosynthetic pathway and led to distinct profiles of sphingoid bases accumulation. Dodecyltributylphosphonium chloride and 1-decyl-3-methylimidazolium chloride induced the accumulation of sphingosine and of a yet unknown sphingoid base, respectively, while cholinium decanoate did not seem to accumulate any of these intermediates. This study brings further light to the roles of sphingoid bases in A. nidulans. In particular, sphingosine as a possible response mediator to cell wall damage induced by dodecyltributylphosphonium chloride, and involvement of an unknown sphingoid base in the response to plasma membrane permeabilization caused by 1-decyl-3-methylimidazolium chloride. In addition, we completed the genetic assignment of the glucosylceramide pathway in A. nidulans through the identification of the sphingolipid Δ4-desaturase gene (AN4405). The knowledge established reinforces the idea of targeting sphingolipids biosynthesis in the search of improved antifungal compounds.
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Affiliation(s)
- Diego O Hartmann
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Daryna Piontkivska
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Carlos J S Moreira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Cristina Silva Pereira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
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Wilding M, Nachtschatt M, Speight R, Scott C. An improved and general streamlined phylogenetic protocol applied to the fatty acid desaturase family. Mol Phylogenet Evol 2017; 115:50-57. [PMID: 28739372 DOI: 10.1016/j.ympev.2017.07.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/13/2017] [Accepted: 07/19/2017] [Indexed: 11/16/2022]
Abstract
Numerous tools to generate phylogenetic estimates are available, but there is no single protocol that will produce an accurate phylogenetic tree for any dataset. Here, we investigated some of those tools, paying particular attention to different alignment algorithms, in order to produce a phylogeny for the integral membrane fatty acid desaturase (FAD) family. Herein, we report a novel streamlined protocol which utilises peptide pattern recognition (PPR). This protocol can theoretically be applied universally to generate accurate multiple sequence alignments and improve downstream phylogenetic analyses. Applied to the desaturases, the protocol generated the first detailed phylogenetic estimates for the family since 2003, which suggested they may have evolved from three functionally distinct desaturases and further, that desaturases evolved first in cyanobacteria. In addition to the phylogenetic outputs, we mapped PPR sequence motifs onto an X-ray protein structure to provide insights into biochemical function and demonstrate the complementarity of PPR and phylogenetics.
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Affiliation(s)
- Matthew Wilding
- CSIRO Land and Water, Black Mountain, Canberra, ACT 2601, Australia.
| | - Matthias Nachtschatt
- CSIRO Land and Water, Black Mountain, Canberra, ACT 2601, Australia; Queensland University of Technology (QUT), Brisbane, QLD 4001, Australia
| | - Robert Speight
- Queensland University of Technology (QUT), Brisbane, QLD 4001, Australia
| | - Colin Scott
- CSIRO Land and Water, Black Mountain, Canberra, ACT 2601, Australia
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Li Y, Lou Y, Mu T, Ke A, Ran Z, Xu J, Chen J, Zhou C, Yan X, Xu Q, Tan Y. Sphingolipids in marine microalgae: Development and application of a mass spectrometric method for global structural characterization of ceramides and glycosphingolipids in three major phyla. Anal Chim Acta 2017; 986:82-94. [PMID: 28870328 DOI: 10.1016/j.aca.2017.07.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/14/2017] [Accepted: 07/16/2017] [Indexed: 01/01/2023]
Abstract
Sphingolipid compositions are crucial for the structural and physiological properties of microalgae membranes. In the present study, we developed a quadrupole time-of-flight (Q-TOF) mass spectrometric method based on MSE data collection for the identification of sphingolipids with high efficiency, selectivity, sensitivity and mass accuracy and applied this method for precise structural identification and quantitative profiling of ceramides and glycosphingolipids in total lipid extracts from 17 strains of microalgae, including 11 strains of diatom, 3 strains of dinoflagellate and 3 strains of haptophyta. Using this method, four species of sphingolipids including 27 ceramides, 13 monosaccharide ceramides, 18 disaccharide ceramides and 18 trisaccharide ceramides were identified. The compositions of sphingolipid-included glycosyl moieties, long chain bases and N-acyl chains showed a significant difference among different microalgae categories. Some long chain bases including d19:2, d19:3 and d19:4, glycosyl moieties including disaccharide and trisaccharide, and N-acyl chains such as 14:0, 14:1, 24:0, 24:1, h18:1, h19:1 and h22:0-2 can be chosen as the molecular signature for microalgae from three major phyla. This methodology will be useful for a wide range of physiological and pathological studies of sphingolipids. Furthermore, the diversity of sphingolipid structure could provide a new criterion for microalgae chemotaxonomy.
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Affiliation(s)
- Yanrong Li
- Key Laboratory of Applied Marine Biotechnology, Ningbo University, Chinese Ministry of Education, Ningbo, Zhejiang 315211, China; Ningbo Institute of Oceanography, Ningbo, Zhejiang 315832, China
| | - Yamin Lou
- Key Laboratory of Applied Marine Biotechnology, Ningbo University, Chinese Ministry of Education, Ningbo, Zhejiang 315211, China
| | - Tong Mu
- Ningbo Institute of Oceanography, Ningbo, Zhejiang 315832, China
| | - Aiying Ke
- Zhejiang Mariculture Research Institute, Wenzhou 325000, China
| | - Zhaoshou Ran
- Key Laboratory of Applied Marine Biotechnology, Ningbo University, Chinese Ministry of Education, Ningbo, Zhejiang 315211, China
| | - Jilin Xu
- Key Laboratory of Applied Marine Biotechnology, Ningbo University, Chinese Ministry of Education, Ningbo, Zhejiang 315211, China.
| | - Juanjuan Chen
- Key Laboratory of Applied Marine Biotechnology, Ningbo University, Chinese Ministry of Education, Ningbo, Zhejiang 315211, China
| | - Chengxu Zhou
- Key Laboratory of Applied Marine Biotechnology, Ningbo University, Chinese Ministry of Education, Ningbo, Zhejiang 315211, China
| | - Xiaojun Yan
- Ningbo Institute of Oceanography, Ningbo, Zhejiang 315832, China.
| | - Qingshan Xu
- Lijing Chenhai Baoer Bio. Ltd., Lijiang, Yunnan 674100, China
| | - Yinghong Tan
- Lijing Chenhai Baoer Bio. Ltd., Lijiang, Yunnan 674100, China
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6
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Bhatt MR, Khatri Y, Rodgers RJ, Martin LL. Role of cytochrome b5 in the modulation of the enzymatic activities of cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1). J Steroid Biochem Mol Biol 2017; 170:2-18. [PMID: 26976652 DOI: 10.1016/j.jsbmb.2016.02.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 02/25/2016] [Accepted: 02/27/2016] [Indexed: 12/13/2022]
Abstract
Cytochrome b5 (cyt b5) is a small hemoprotein that plays a significant role in the modulation of activities of an important steroidogenic enzyme, cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1, CYP17A1). Located in the zona fasciculata and zona reticularis of the adrenal cortex and in the gonads, P450 17A1 catalyzes two different reactions in the steroidogenic pathway; the 17α-hydroxylation and 17,20-lyase, in the endoplasmic reticulum of these respective tissues. The activities of P450 17A1 are regulated by cyt b5 that enhances the 17,20-lyase reaction by promoting the coupling of P450 17A1 and cytochrome P450 reductase (CPR), allosterically. Cyt b5 can also act as an electron donor to enhance the 16-ene-synthase activity of human P450 17A1. In this review, we discuss the many roles of cyt b5 and focus on the modulation of CYP17A1 activities by cyt b5 and the mechanisms involved.
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Affiliation(s)
- Megh Raj Bhatt
- Everest Biotech Pvt. Ltd., Khumaltar, Lalitpur, P.O. Box 21608, Kathmandu 44600, Nepal
| | - Yogan Khatri
- Institute of Biochemistry, Saarland University, 66123 Saarbrücken, Germany
| | - Raymond J Rodgers
- School of Medicine, Robinson Research Institute, University of Adelaide, Adelaide SA 5005, Australia
| | - Lisandra L Martin
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia.
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7
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Michaelson LV, Napier JA, Molino D, Faure JD. Plant sphingolipids: Their importance in cellular organization and adaption. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1861:1329-1335. [PMID: 27086144 PMCID: PMC4970446 DOI: 10.1016/j.bbalip.2016.04.003] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 12/22/2022]
Abstract
Sphingolipids and their phosphorylated derivatives are ubiquitous bio-active components of cells. They are structural elements in the lipid bilayer and contribute to the dynamic nature of the membrane. They have been implicated in many cellular processes in yeast and animal cells, including aspects of signaling, apoptosis, and senescence. Although sphingolipids have a better defined role in animal systems, they have been shown to be central to many essential processes in plants including but not limited to, pollen development, signal transduction and in the response to biotic and abiotic stress. A fuller understanding of the roles of sphingolipids within plants has been facilitated by classical biochemical studies and the identification of mutants of model species. Recently the development of powerful mass spectrometry techniques hailed the advent of the emerging field of lipidomics enabling more accurate sphingolipid detection and quantitation. This review will consider plant sphingolipid biosynthesis and function in the context of these new developments. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
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Affiliation(s)
- Louise V Michaelson
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, UK.
| | - Johnathan A Napier
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, UK.
| | - Diana Molino
- Ecole Normale Supérieure-PSL Research University, Département de Chimie, Sorbonne Universités - UPMC Univ Paris 06, CNRS UMR 8640 PASTEUR, Paris, France.
| | - Jean-Denis Faure
- INRA, Institut Jean-Pierre Bourgin, UMR 1318, ERL CNRS3559, Saclay Plant Sciences, Versailles, France; Agro Paris Tech, Institut Jean-Pierre Bourgin, UMR 1318, ERL CNRS3559, Saclay Plant Sciences, Versailles, France.
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Derbyshire MC, Michaelson L, Parker J, Kelly S, Thacker U, Powers SJ, Bailey A, Hammond-Kosack K, Courbot M, Rudd J. Analysis of cytochrome b(5) reductase-mediated metabolism in the phytopathogenic fungus Zymoseptoria tritici reveals novel functionalities implicated in virulence. Fungal Genet Biol 2015; 82:69-84. [PMID: 26074495 PMCID: PMC4557397 DOI: 10.1016/j.fgb.2015.05.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 12/15/2022]
Abstract
Septoria tritici blotch (STB) caused by the Ascomycete fungus Zymoseptoria tritici is one of the most economically damaging diseases of wheat worldwide. Z. tritici is currently a major target for agricultural fungicides, especially in temperate regions where it is most prevalent. Many fungicides target electron transfer enzymes because these are often important for cell function. Therefore characterisation of genes encoding such enzymes may be important for the development of novel disease intervention strategies. Microsomal cytochrome b5 reductases (CBRs) are an important family of electron transfer proteins which in eukaryotes are involved in the biosynthesis of fatty acids and complex lipids including sphingolipids and sterols. Unlike the model yeast Saccharomyces cerevisiae which possesses only one microsomal CBR, the fully sequenced genome of Z. tritici bears three possible microsomal CBRs. RNA sequencing analysis revealed that ZtCBR1 is the most highly expressed of these genes under all in vitro and in planta conditions tested, therefore ΔZtCBR1 mutant strains were generated through targeted gene disruption. These strains exhibited delayed disease symptoms on wheat leaves and severely limited asexual sporulation. ΔZtCBR1 strains also exhibited aberrant spore morphology and hyphal growth in vitro. These defects coincided with alterations in fatty acid, sphingolipid and sterol biosynthesis observed through GC-MS and HPLC analyses. Data is presented which suggests that Z. tritici may use ZtCBR1 as an additional electron donor for key steps in ergosterol biosynthesis, one of which is targeted by azole fungicides. Our study reports the first functional characterisation of CBR gene family members in a plant pathogenic filamentous fungus. This also represents the first direct observation of CBR functional ablation impacting upon fungal sterol biosynthesis.
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Affiliation(s)
- Mark C Derbyshire
- Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK.
| | - Louise Michaelson
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Josie Parker
- Centre for Cytochrome P450 Diversity, Institute of Life Science, College of Medicine, Swansea University Singleton Park, Swansea SA2 8PP, Wales, UK
| | - Steven Kelly
- Centre for Cytochrome P450 Diversity, Institute of Life Science, College of Medicine, Swansea University Singleton Park, Swansea SA2 8PP, Wales, UK
| | | | - Stephen J Powers
- Department of Computational and Systems Biology, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Andy Bailey
- Bristol University, Senate House, Tyndall Avenue, Bristol BS8 1TH, UK
| | - Kim Hammond-Kosack
- Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Mikael Courbot
- Syngenta, Syngenta AG, Schaffhauserstrasse, CH-4332 Stein, Switzerland
| | - Jason Rudd
- Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK.
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Tian Y, Zhao GY, Fang W, Xu Q, Tan RX. Δ10(E)-Sphingolipid Desaturase Involved in Fusaruside Mycosynthesis and Stress Adaptation in Fusarium graminearum. Sci Rep 2015; 5:10486. [PMID: 25994332 PMCID: PMC4440215 DOI: 10.1038/srep10486] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 04/15/2015] [Indexed: 12/20/2022] Open
Abstract
Sphingolipids are biologically important and structurally distinct cell membrane components. Fusaruside (1) is a 10,11-unsaturated immunosuppressive fungal sphingolipid with medical potentials for treating liver injury and colitis, but its poor natural abundance bottlenecks its druggability. Here, fusaruside is clarified biosynthetically, and its efficacy-related 10,11-double bond can be generated under the regioselective catalysis of an unprecedented Δ10(E)-sphingolipid desaturase (Δ10(E)-SD). Δ10(E)-SD shares 17.7% amino acid sequence similarity with a C9-unmethylated Δ10-sphingolipid desaturase derived from a marine diatom, and 55.7% with Δ8(E)-SD from Fusarium graminearum. Heterologous expression of Δ10(E)-SD in Pichia pastoris has been established to facilitate a reliable generation of 1 through the Δ10(E)-SD catalyzed desaturation of cerebroside B (2), an abundant fungal sphingolipid. Site directed mutageneses show that the conserved histidines of Δ10(E)-SD are essential for the 10,11-desaturation catalysis, which is also preconditioned by the C9-methylation of the substrate. Moreover, Δ10(E)-SD confers improved survival and faster growth to fungal strains at low temperature and high salinity, in parallel with to higher contents of 1 in the mycelia. Collectively, the investigation describes a new Δ10(E)-sphingolipid desaturase with its heterologous expression fundamentalizing a biotechnological supply of 1, and eases the follow-up clarification of the immunosuppression and stress-tolerance mechanism.
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Affiliation(s)
- Yuan Tian
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Guo Y. Zhao
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Wei Fang
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Qiang Xu
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Ren X. Tan
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
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Ma YH, Wang X, Niu YF, Yang ZK, Zhang MH, Wang ZM, Yang WD, Liu JS, Li HY. Antisense knockdown of pyruvate dehydrogenase kinase promotes the neutral lipid accumulation in the diatom Phaeodactylum tricornutum. Microb Cell Fact 2014; 13:100. [PMID: 25106441 DOI: 10.1007/978-94-007-7864-1_127-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/03/2014] [Indexed: 05/26/2023] Open
Abstract
BACKGROUND Microalgae have been an emerging biofuel resource; however, the germplasm improvement has been slow due to the lack of molecular tools. Pyruvate dehydrogenase kinase (PDK) deactivates the pyruvate dehydrogenase complex (PDC) which catalyzes the oxidative decarboxylation of pyruvate. Acetyl-CoA production via PDC is important in plant tissues that are active in fatty acid synthesis. RESULTS A 1261-bp cDNA of a putative PDK gene (PtPDK) was cloned from a diatom Phaeodactylum tricornutum, and PtPDK antisense knockdown transgenic diatoms were generated. Both PtPDK transcript abundance and enzyme activity were reduced significantly due to antisense knockdown of PtPDK. Neutral lipid content of transgenic diatom cells increased up to 82% as determined by Nile red staining, and fatty acid composition was not altered. Transgenic cells showed slightly lower growth rate but similar cell size with the wild type, hence retaining similar biomass productivity. CONCLUSIONS This work first obtained a successful engineered diatom regulating a key gene involved in lipid metabolism. Our findings also provide powerful indications in enhancing microalgal lipid production by metabolic engineering for biofuel industry.
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