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de Novaes MIC, Robertson C, Doyle VP, Burk D, Thomas-Sharma S. Distribution and Sequestration of Cercosporin by Cercospora cf. flagellaris. PHYTOPATHOLOGY 2024; 114:1822-1831. [PMID: 38700938 DOI: 10.1094/phyto-09-23-0310-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
Plant-pathogenic fungi produce toxins as virulence factors in many plant diseases. In Cercospora leaf blight of soybean caused by Cercospora cf. flagellaris, symptoms are a consequence of the production of a perylenequinone toxin, cercosporin, which is light-activated to produce damaging reactive oxygen species. Cercosporin is universally toxic to cells, except to the cells of the producer. The current model of self-resistance to cercosporin is largely attributed to the maintenance of cercosporin in a chemically reduced state inside hyphae, unassociated with cellular organelles. However, in another perylenequinone-producing fungus, Phaeosphaeria sp., the toxin was specifically sequestered inside lipid droplets (LDs) to prevent reactive oxygen species production. This study hypothesized that LD-based sequestration of cercosporin occurred in C. cf. flagellaris and that lipid-inhibiting fungicides could inhibit toxin production. Confocal microscopy using light-cultured C. cf. flagellaris indicated that 3-day-old hyphae contained two forms of cercosporin distributed in two types of hyphae. Reduced cercosporin was uniformly distributed in the cytoplasm of thick, primary hyphae, and, contrary to previous studies, active cercosporin was observed specifically in the LDs of thin, secondary hyphae. The production of hyphae of two different thicknesses, a characteristic of hemibiotrophic plant pathogens, has not been documented in C. cf. flagellaris. No correlation was observed between cercosporin production and total lipid extracted, and two lipid-inhibiting fungicides had little effect on fungal growth in growth-inhibition assays. This study lays a foundation for exploring the importance of pathogen lifestyle, toxin production, and LD content in the pathogenicity and symptomology of Cercospora.
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Affiliation(s)
- Maria Izabel Costa de Novaes
- Department of Plant Pathology & Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803
| | - Clark Robertson
- Louisiana State University Agricultural Center, 20140 Iowa Street, Livingston, LA 70754
| | - Vinson P Doyle
- Department of Plant Pathology & Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803
| | - David Burk
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA 70803
| | - Sara Thomas-Sharma
- Department of Plant Pathology & Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803
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Brunetti SC, Arseneault MKM, Gulick PJ. The caleosin RD20/CLO3 regulates lateral root development in response to abscisic acid and regulates flowering time in conjunction with the caleosin CLO7. JOURNAL OF PLANT PHYSIOLOGY 2023; 290:154102. [PMID: 37812854 DOI: 10.1016/j.jplph.2023.154102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/07/2023] [Accepted: 09/23/2023] [Indexed: 10/11/2023]
Abstract
The caleosins are encoded by multi-gene families in Arabidopsis thaliana and other plant species. This work investigates the role of two family members, RD20/CLO3 and CLO7, in flowering transition and in root development in response to ABA treatment. Gene expression of the caleosin RD20/CLO3 is induced by ABA in the root tissues and RD20/CLO3 has a negative affect on the total number of lateral roots as well as the length of the lateral roots in response to ABA treatment. The rd20/clo3 mutant has more and longer lateral roots in response to ABA treatment compared to the wild-type, showing that RD20/CLO3 plays a role in the ABA signaling pathway affecting this trait. In contrast, the caleosin CLO7 is not expressed in the roots and does not affect root architecture in response to ABA treatment. The disruption of both RD20/CLO3 and CLO7 together causes a dramatic early-flowering phenotype under long-day conditions, whereas single mutations in these genes do not affect flowering time under these conditions. Both yeast two-hybrid and bimolecular fluorescence complementation showed that both RD20/CLO3 and CLO7 interact with each other and can form homodimers and heterodimers. Taken together, these findings suggest that members of the caleosin gene family play both different and redundant roles in plant development.
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Affiliation(s)
- Sabrina C Brunetti
- Biology Department, Concordia University, 7141 Sherbrooke W, Montreal, Quebec, H4B 1R6, Canada
| | - Michelle K M Arseneault
- Biology Department, Concordia University, 7141 Sherbrooke W, Montreal, Quebec, H4B 1R6, Canada
| | - Patrick J Gulick
- Biology Department, Concordia University, 7141 Sherbrooke W, Montreal, Quebec, H4B 1R6, Canada.
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Hanano A, Blée E, Murphy DJ. Caleosin/peroxygenases: multifunctional proteins in plants. ANNALS OF BOTANY 2023; 131:387-409. [PMID: 36656070 PMCID: PMC10072107 DOI: 10.1093/aob/mcad001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 01/08/2023] [Indexed: 06/01/2023]
Abstract
BACKGROUND Caleosin/peroxygenases (CLO/PXGs) are a family of multifunctional proteins that are ubiquitous in land plants and are also found in some fungi and green algae. CLO/PXGs were initially described as a class of plant lipid-associated proteins with some similarities to the oleosins that stabilize lipid droplets (LDs) in storage tissues, such as seeds. However, we now know that CLO/PXGs have more complex structures, distributions and functions than oleosins. Structurally, CLO/PXGs share conserved domains that confer specific biochemical features, and they have diverse localizations and functions. SCOPE This review surveys the structural properties of CLO/PXGs and their biochemical roles. In addition to their highly conserved structures, CLO/PXGs have peroxygenase activities and are involved in several aspects of oxylipin metabolism in plants. The enzymatic activities and the spatiotemporal expression of CLO/PXGs are described and linked with their wider involvement in plant physiology. Plant CLO/PXGs have many roles in both biotic and abiotic stress responses in plants and in their responses to environmental toxins. Finally, some intriguing developments in the biotechnological uses of CLO/PXGs are addressed. CONCLUSIONS It is now two decades since CLO/PXGs were first recognized as a new class of lipid-associated proteins and only 15 years since their additional enzymatic functions as a new class of peroxygenases were discovered. There are many interesting research questions that remain to be addressed in future physiological studies of plant CLO/PXGs and in their recently discovered roles in the sequestration and, possibly, detoxification of a wide variety of lipidic xenobiotics that can challenge plant welfare.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), Damascus, Syria
| | - Elizabeth Blée
- Former Head of Phyto-oxylipins laboratory, Institute of Plant Molecular Biology, University of Strasbourg, France
| | - Denis J Murphy
- School of Applied Sciences, University of South Wales, Treforest, UK
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), Damascus, Syria
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Che L, Huang J, Lin JX, Xu CY, Wu XM, Du ZB, Wu JS, Lin ZN, Lin YC. Aflatoxin B1 exposure triggers hepatic lipotoxicity via p53 and perilipin 2 interaction-mediated mitochondria-lipid droplet contacts: An in vitro and in vivo assessment. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130584. [PMID: 37055989 DOI: 10.1016/j.jhazmat.2022.130584] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/17/2022] [Accepted: 12/07/2022] [Indexed: 06/19/2023]
Abstract
Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins widely found in food contaminants, and its target organ is the liver. It poses a major food security and public health threat worldwide. However, the lipotoxicity mechanism of AFB1 exposure-induced liver injury remains unclear and requires further elucidation. Herein, we investigated the potential hepatic lipotoxicity of AFB1 exposure using in vitro and in vivo models to assess the public health hazards of high dietary AFB1 exposure. We demonstrated that low-dose of AFB1 (1.25 μM for 48 h, about one-fifth of the IC50 in HepG2 and HepaRG cells, IC50 are 5.995 μM and 5.266 μM, respectively) exposure significantly induced hepatic lipotoxicity, including abnormal lipid droplets (LDs) growth, mitochondria-LDs contacts increase, lipophagy disruption, and lipid accumulation. Mechanistically, we showed that AFB1 exposure promoted the mitochondrial p53 (mito-p53) and LDs-associated protein perilipin 2 (PLIN2) interaction-mediated mitochondria-LDs contacts, resulting in lipid accumulation in hepatocytes. Mito-p53-targeted inhibition, knockdown of PLIN2, and rapamycin application efficiently promoted the lysosome-dependent lipophagy and alleviated the hepatic lipotoxicity and liver injury induced by AFB1 exposure. Overall, our study found that mito-p53 and PLIN2 interaction mediates three organelles-mitochondria, LDs, and lysosomal networks to regulate lipid homeostasis in AFB1 exposure-induced hepatotoxicity, revealing how this unique trio of organelles works together and provides a novel insight into the targeted intervention in inter-organelle lipid sensing and trafficking for alleviating hazardous materials-induced hepatic lipotoxicity.
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Affiliation(s)
- Lin Che
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jing Huang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jin-Xian Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Chi-Yu Xu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Xin-Mou Wu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Ze-Bang Du
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jia-Shen Wu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Zhong-Ning Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China.
| | - Yu-Chun Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China.
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Tran AD, Cho K, Han O. Rice peroxygenase catalyzes lipoxygenase-dependent regiospecific epoxidation of lipid peroxides in the response to abiotic stressors. Bioorg Chem 2023; 131:106285. [PMID: 36450198 DOI: 10.1016/j.bioorg.2022.106285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 11/15/2022] [Accepted: 11/17/2022] [Indexed: 11/25/2022]
Abstract
The peroxygenase pathway plays pivotal roles in plant responses to oxidative stress and other environmental stressors. Analysis of a network of co-expressed stress-regulated rice genes demonstrated that expression of OsPXG9 is negatively correlated with expression of genes involved in jasmonic acid biosynthesis. DNA sequence analysis and structure/function studies reveal that OsPXG9 is a caleosin-like peroxygenase with amphipathic α-helices that localizes to lipid droplets in rice cells. Enzymatic studies demonstrate that 12-epoxidation is slightly more favorable with 9(S)-hydroperoxyoctadecatrienoic acid than with 9(S)-hydroperoxyoctadecadienoic acid as substrate. The products of 12-epoxidation are labile, and the epoxide ring is hydrolytically cleaved into corresponding trihydroxy compounds. On the other hand, OsPXG9 catalyzed 15-epoxidation of 13(S)-hydroperoxyoctadecatrienoic acid generates a relatively stable epoxide product. Therefore, the regiospecific 12- or 15-epoxidation catalyzed by OsPXG9 strongly depends on activation of the 9- or 13- peroxygenase reaction pathways, with their respective preferred substrates. The relative abundance of products in the 9-PXG and 13-PXG pathways suggest that the 12-epoxidation involves intramolecular oxygen transfer while the 15-epoxidation can proceed via intramolecular or intermolecular oxygen transfer. Expression of OsPXG9 is up-regulated by abiotic stimuli such as drought and salt stress, but it is down-regulated by biotic stimuli such as flagellin 22 and salicylic acid. The results suggest that the primary function of OsPXG9 is to modulate the level of lipid peroxides to facilitate effective defense responses to abiotic and biotic stressors.
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Affiliation(s)
- Anh Duc Tran
- Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Kyoungwon Cho
- Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Oksoo Han
- Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea.
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Perez-Matas E, Hanano A, Moyano E, Bonfill M, Cusido RM, Palazon J. Insights into the control of taxane metabolism: Molecular, cellular, and metabolic changes induced by elicitation in Taxus baccata cell suspensions. FRONTIERS IN PLANT SCIENCE 2022; 13:942433. [PMID: 35968149 PMCID: PMC9372332 DOI: 10.3389/fpls.2022.942433] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
More knowledge is needed about the molecular/cellular control of paclitaxel (PTX) production in Taxus spp. cell cultures. In this study, the yield of this anticancer agent in Taxus baccata cell suspensions was improved 11-fold after elicitation with coronatine (COR) compared to the untreated cells, and 18-fold when co-supplemented with methyl-β-cyclodextrins (β-CDs). In the dual treatment, the release of taxanes from the producer cells was greatly enhanced, with 81.6% of the total taxane content being found in the medium at the end of the experiment. The experimental conditions that caused the highest PTX production also induced its maximum excretion, and increased the expression of taxane biosynthetic genes, especially the flux-limiting BAPT and DBTNBT. The application of COR, which activates PTX biosynthesis, together with β - CDs, which form inclusion complexes with PTX and related taxanes, is evidently an efficient strategy for enhancing PTX production and release to the culture medium. Due to the recently described role of lipid droplets (LDs) in the trafficking and accumulation of hydrophobic taxanes in Taxus spp. cell cultures, the structure, number and taxane storage capacity of these organelles was also studied. In elicited cultures, the number of LDs increased and they mainly accumulated taxanes with a side chain, especially PTX. Thus, PTX constituted up to 50-70% of the total taxanes found in LDs throughout the experiment in the COR + β - CD-treated cultures. These results confirm that LDs can store taxanes and distribute them inside and outside cells.
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Affiliation(s)
- Edgar Perez-Matas
- Secció de Fisiologia Vegetal, Facultat de Farmacia i Ciències de l’Alimentació, Universitat de Barcelona, Barcelona, Spain
| | - Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria, Damascus, Syria
| | - Elisabeth Moyano
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Mercedes Bonfill
- Secció de Fisiologia Vegetal, Facultat de Farmacia i Ciències de l’Alimentació, Universitat de Barcelona, Barcelona, Spain
| | - Rosa M. Cusido
- Secció de Fisiologia Vegetal, Facultat de Farmacia i Ciències de l’Alimentació, Universitat de Barcelona, Barcelona, Spain
| | - Javier Palazon
- Secció de Fisiologia Vegetal, Facultat de Farmacia i Ciències de l’Alimentació, Universitat de Barcelona, Barcelona, Spain
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Liu X, Yang Z, Wang Y, Shen Y, Jia Q, Zhao C, Zhang M. Multiple caleosins have overlapping functions in oil accumulation and embryo development. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:3946-3962. [PMID: 35419601 DOI: 10.1093/jxb/erac153] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
Caleosins are lipid droplet- and endoplasmic reticulum-associated proteins. To investigate their functions in oil accumulation, expression levels of caleosins in developing seeds of Arabidopsis thaliana were examined and four seed-expressed caleosins (CLO1, CLO2, CLO4, and CLO6) were identified. The four single mutants showed similar minor changes of fatty acid composition in seeds. Two double mutants (clo1 clo2 and clo1×clo2) demonstrated distinct changes of fatty acid composition, a 16-23% decrease of oil content, and a 10-13% decrease of seed weight. Moreover, a 40% decrease of oil content, further fatty acid changes, and misshapen membranes of smaller lipid droplets were found in seeds of quadruple CLO RNAi lines. Notably, ~40% of quadruple CLO RNAi T1 seeds failed to germinate, and deformed embryos and seedlings were also observed. Complementation experiments showed that CLO1 rescued the phenotype of clo1 clo2. Overexpression of CLO1 in seedlings and BY2 cells increased triacylglycerol content up to 73.6%. Transcriptome analysis of clo1 clo2 developing seeds showed that expression levels of some genes related to lipid, embryo development, calcium signaling, and stress responses were affected. Together, these results suggest that the major seed-expressed caleosins have overlapping functions in oil accumulation and show pleiotropic effects on embryo development.
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Affiliation(s)
- Xiangling Liu
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | | | - Yun Wang
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | | | - Qingli Jia
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Cuizhu Zhao
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Meng Zhang
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
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Breuer MR, Dasgupta A, Vasselli JG, Lin X, Shaw BD, Sachs MS. The Antidepressant Sertraline Induces the Formation of Supersized Lipid Droplets in the Human Pathogen Cryptococcus neoformans. J Fungi (Basel) 2022; 8:jof8060642. [PMID: 35736125 PMCID: PMC9224953 DOI: 10.3390/jof8060642] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/13/2022] [Accepted: 06/15/2022] [Indexed: 01/11/2023] Open
Abstract
The prevalence and increasing incidence of fungal infections globally is a significant worldwide health problem. Cryptococcosis, primarily caused by the pathogenic yeast Cryptococcus neoformans, is responsible for approximately 181,000 estimated deaths annually. The scarcity of treatments and the increasing resistance to current therapeutics highlight the need for the development of antifungal agents which have novel mechanisms of action and are suitable for clinical use. Repurposing existing FDA-approved compounds as antimycotic therapeutics is a promising strategy for the rapid development of such new treatments. Sertraline (SRT), a commonly prescribed antidepressant, is a broad-spectrum antifungal agent with particular efficacy against C. neoformans. However, the effect of SRT on fungal physiology is not understood. Here, we report that SRT induces the formation of supersized lipid droplets (SLDs) in C. neoformans, and in Candida albicans, Saccharomyces cerevisiae, and Aspergillus fumigatus. SLDs were not induced in C. neoformans by treatment with the antifungal fluconazole (FLC), consistent with SRT and FLC acting differently to perturb C. neoformans physiology. The formation of SLDs in response to SRT indicates that this compound alters the lipid metabolism of C. neoformans. Moreover, the SRT-induced enlargement of LDs in other fungal species may indicate a common fungal response to SRT.
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Affiliation(s)
- Matthew R. Breuer
- Department of Biology, Texas A&M University, College Station, TX 77843, USA; (M.R.B.); (A.D.)
| | - Ananya Dasgupta
- Department of Biology, Texas A&M University, College Station, TX 77843, USA; (M.R.B.); (A.D.)
| | - Joseph G. Vasselli
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843, USA; (J.G.V.); (B.D.S.)
| | - Xiaorong Lin
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA;
| | - Brian D. Shaw
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843, USA; (J.G.V.); (B.D.S.)
| | - Matthew S. Sachs
- Department of Biology, Texas A&M University, College Station, TX 77843, USA; (M.R.B.); (A.D.)
- Correspondence: ; Tel.: +1-(979)-845-5930
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9
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Yaseen S, Hanano A. Quantitative PCR (qPCR) Reveals that the Aflatoxin-Free Pistachio Samples Can Be Potentially Contaminated with Fungal Materials. FOOD ANAL METHOD 2022. [DOI: 10.1007/s12161-022-02327-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Hanano A, Perez-Matas E, Shaban M, Cusido RM, Murphy DJ. Characterization of lipid droplets from a Taxus media cell suspension and their potential involvement in trafficking and secretion of paclitaxel. PLANT CELL REPORTS 2022; 41:853-871. [PMID: 34984531 DOI: 10.1007/s00299-021-02823-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
Our paper describes the potential roles of lipid droplets of Taxus media cell suspension in the biosynthesis and secretion of paclitaxel and, therefore, highlights their involvement in improving its production. Paclitaxel (PTX) is a highly potent anticancer drug that is mainly produced using Taxus sp. cell suspension cultures. The main purpose of the current study is to characterize cellular LDs from T. media cell suspension with a particular focus on the biological connection of their associated proteins, the caleosins (CLOs), with the biosynthesis and secretion of PTX. A pure LD fraction obtained from T. media cells and characterized in terms of their proteome. Interestingly, the cellular LD in T. media sequester the PTX. This was confirmed in vitro, where about 96% of PTX (C0PTX,aq [mg L-1]) in the aqueous solution was partitioned into the isolated LDs. Furthermore, silencing of CLO-encoding genes in the T. media cells led to a net decrease in the number and size of LDs. This coincided with a significant reduction in expression levels of TXS, DBAT and DBTNBT, key genes in the PTX biosynthesis pathway. Subsequently, the biosynthesis of PTX was declined in cell culture. In contrast, treatment of cells with 13-hydroperoxide C18:3, a substrate of the peroxygenase activity, induced the expression of CLOs, and, therefore, the accumulation of cellular LDs in the T. media cells cultures, thus increasing the PTX secretion. The accumulation of stable LDs is critically important for effective secretion of PTX. This is modulated by the expression of caleosins, a class of LD-associated proteins with a dual role conferring the structural stability of LDs as well as regulating lipidic bioactive metabolites via their enzymatic activity, thus enhancing the biosynthesis of PTX.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria.
| | - Edgar Perez-Matas
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII Sn., 08028, Barcelona, Spain
| | - Mouhnad Shaban
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria
| | - Rosa M Cusido
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII Sn., 08028, Barcelona, Spain
| | - Denis J Murphy
- Genomics and Computational Biology Group, University of South Wales, Pontypridd, Wales, UK
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Mahfouz S, Mansour G, Murphy DJ, Hanano A. Dioxin impacts on lipid metabolism of soil microbes: towards effective detection and bioassessment strategies. BIORESOUR BIOPROCESS 2020. [DOI: 10.1186/s40643-020-00347-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AbstractDioxins are the most toxic known environmental pollutants and are mainly formed by human activities. Due to their structural stability, dioxins persist for extended periods and can be transported over long distances from their emission sources. Thus, dioxins can be accumulated to considerable levels in both human and animal food chains. Along with sediments, soils are considered the most important reservoirs of dioxins. Soil microorganisms are therefore highly exposed to dioxins, leading to a range of biological responses that can impact the diversity, genetics and functional of such microbial communities. Dioxins are very hydrophobic with a high affinity to lipidic macromolecules in exposed organisms, including microbes. This review summarizes the genetic, molecular and biochemical impacts of dioxins on the lipid metabolism of soil microbial communities and especially examines modifications in the composition and architecture of cell membranes. This will provide a useful scientific benchmark for future attempts at soil ecological risk assessment, as well as in identifying potential dioxin-specific-responsive lipid biomarkers. Finally, potential uses of lipid-sequestering microorganisms as a part of biotechnological approaches to the bio-management of environmental contamination with dioxins are discussed.
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12
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Guo H, Ji J, Wang JS, Sun X. Co-contamination and interaction of fungal toxins and other environmental toxins. Trends Food Sci Technol 2020. [DOI: 10.1016/j.tifs.2020.06.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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13
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Li X, Jiang Y, Ma L, Ma X, Liu Y, Shan J, Ma K, Xing F. Comprehensive Transcriptome and Proteome Analyses Reveal the Modulation of Aflatoxin Production by Aspergillus flavus on Different Crop Substrates. Front Microbiol 2020; 11:1497. [PMID: 32760360 PMCID: PMC7371938 DOI: 10.3389/fmicb.2020.01497] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/09/2020] [Indexed: 01/26/2023] Open
Abstract
As a natural severe contaminant of stored grains and other crops worldwide, Aspergillus flavus can produce aflatoxins (AFs), the most powerful naturally producing toxic and hepatocarcinogenic compounds. AFs production is regulated by diverse factors including AFs cluster genes, transcription factors, regulators, and environmental factors. Among them, crop substrate is one of the most important factors. Here, we found that AFB1 production was significantly higher in maize and rice broth than in peanut broth. To clarify the mechanisms involved, complementary transcriptomic and proteomic analyses were performed to identify changes in A. flavus incubated in the three crop substrates. The results indicated that fewer genes and proteins were differentially expressed between maize and rice substrates, whereas more differentially expressed genes were observed between maize/rice broth and peanut broth. In particular, the genes involved in the initial step of AFs biosynthesis (aflA, aflB, and aflC) and the ACCase-encoding gene accA were significantly upregulated on the maize and rice substrates. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses indicated that carbon-metabolism-related genes were obviously enriched in the maize broth, and the genes involved in acetyl-CoA accumulation and consumption were up- and downregulated, respectively. Several genes involved in the regulation of AFs biosynthesis, including veA, ppoB, snf1, and the G-protein-coupled receptor (GPCR) genes, were differentially expressed on the three substrates, suggesting that these genes may be also involved in sugar signal sensing, transfer, and regulation. Interestingly, by the correlation analyses of transcriptome and proteome, trehalose metabolism genes, aldehyde dehydrogenase gene, and tryptophan synthase gene were found to be relevant with the regulation of AFs production on different crop substrates. Taken together, the differential expressions of the AFs cluster genes, several regulatory genes, and carbon metabolism genes were involved in the comprehensive modulation of AFs production on different crop substrates.
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Affiliation(s)
- Xu Li
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yiran Jiang
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Longxue Ma
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaoyun Ma
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yang Liu
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China.,School of Food Science and Engineering, Foshan University, Foshan, China
| | - Jihao Shan
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kang Ma
- Division of Chemical Metrology and Analytical Science, National Institute of Metrology, Beijing, China
| | - Fuguo Xing
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
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Hammoudeh N, Soukkarieh C, Murphy DJ, Hanano A. Involvement of hepatic lipid droplets and their associated proteins in the detoxification of aflatoxin B 1 in aflatoxin-resistance BALB/C mouse. Toxicol Rep 2020; 7:795-804. [PMID: 32642446 PMCID: PMC7334552 DOI: 10.1016/j.toxrep.2020.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 06/04/2020] [Accepted: 06/11/2020] [Indexed: 12/14/2022] Open
Abstract
The highly potent carcinogen, Aflatoxin B1, induces liver cancer in many animals including humans but some mice strains are highly resistant. This murine resistance is due to a rapid detoxification of AFB1. Hepatic lipid droplets (LDs) ultimately impact the liver functions but their potential role in AFB1 detoxification has not been addressed. This study describes the structural and functional impacts on hepatic LDs in BALB/C mice after exposure to 44 (low dose) or 663 (high dose) μg AFB1/kg of body weight. After 7 days, the liver of AFB1-dosed mice did not accumulate any detectable AFB1 or its metabolites and this was associated with a net increase in gene transcripts of the AhR-mediating pathway. Of particular interest, the livers of high-dose mice accumulated many more LDs than those of low-dose mice. This was accompanied with a net increase in transcript levels of LD-associated protein-encoding genes including Plin2, Plin3 and Cideb and an alteration in the LDs lipid profiles that could be likely due to the induction of lipoxygenase and cyclooxygenase genes. Interestingly, our data suggest that hepatic LDs catalyze the in vitro activation of AFB1 into AFB1-exo-8,9-epoxide and subsequent hydrolysis of this epoxide into its corresponding dihydrodiol. Finally, transcript levels of CYP1A2, CYP1B1, GSTA3 and EH1 genes were elevated in livers of high-dose mice. These data suggest new roles for hepatic LDs in the trapping and detoxifying of aflatoxins.
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Affiliation(s)
- Nour Hammoudeh
- Department of Animal Biology, Damascus University, Damascus, Syria
| | - Chadi Soukkarieh
- Department of Animal Biology, Damascus University, Damascus, Syria
| | - Denis J Murphy
- Genomics and Computational Biology Group, University of South Wales, Wales, United Kingdom
| | - Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria
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Lamberti C, Nebbia S, Balestrini R, Marengo E, Manfredi M, Pavese V, Cirrincione S, Giuffrida MG, Cavallarin L, Acquadro A, Abbà S. Identification of a caleosin associated with hazelnut (Corylus avellana L.) oil bodies. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:404-409. [PMID: 32027456 DOI: 10.1111/plb.13096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 01/30/2020] [Indexed: 06/10/2023]
Abstract
Caleosins are involved in several cellular and biological processes that are closely associated with the synthesis, degradation and stability of oil bodies (OB). Because of the importance and the multiple roles of these OB-associated proteins, in silico identification of sequences corresponding to putative caleosins in the hazelnut genome has been performed, and the association with seed OB was verified using a proteomic approach. Five full-length sequences (CavCLO-H1, CavCLO-H2, CavCLO-H3, CavCLO-L1, CavCLO-L2), belonging to the two groups of caleosins (H and L), have been identified in the hazelnut genome. The number of identified caleosins is in agreement with that previously observed in other plant species, confirming that caleosins comprise small gene families in plants. A proteomic approach allowed us to verify only the presence of CavCLO-H1 in hazelnut OB, suggesting that several members inside this family could have different roles during plant growth and development. In silico analysis also suggests that CavCLO-H1 may act as a peroxygenase.
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Affiliation(s)
- C Lamberti
- Istituto di Scienze delle Produzioni Alimentari, CNR, Grugliasco, Italy
| | - S Nebbia
- Istituto di Scienze delle Produzioni Alimentari, CNR, Grugliasco, Italy
| | - R Balestrini
- Istituto per la Protezione Sostenibile delle Piante, CNR, Torino, Italy
| | - E Marengo
- DiSIT, Università del Piemonte Orientale, Alessandria, Italy
| | - M Manfredi
- DiSIT, Università del Piemonte Orientale, Alessandria, Italy
| | - V Pavese
- DiSAFA, Università di Torino, Grugliasco, Italy
| | - S Cirrincione
- Istituto di Scienze delle Produzioni Alimentari, CNR, Grugliasco, Italy
| | - M G Giuffrida
- Istituto di Scienze delle Produzioni Alimentari, CNR, Grugliasco, Italy
| | - L Cavallarin
- Istituto di Scienze delle Produzioni Alimentari, CNR, Grugliasco, Italy
| | - A Acquadro
- DiSAFA, Università di Torino, Grugliasco, Italy
| | - S Abbà
- Istituto per la Protezione Sostenibile delle Piante, CNR, Torino, Italy
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Hanano A, Almousally I, Shaban M. Exposure of Aspergillus flavus NRRL 3357 to the Environmental Toxin, 2,3,7,8-Tetrachlorinated Dibenzo- p-Dioxin, Results in a Hyper Aflatoxicogenic Phenotype: A Possible Role for Caleosin/Peroxygenase (AfPXG). Front Microbiol 2019; 10:2338. [PMID: 31681203 PMCID: PMC6803392 DOI: 10.3389/fmicb.2019.02338] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 09/25/2019] [Indexed: 12/19/2022] Open
Abstract
Aflatoxins (AFs) as potent food contaminants are highly detrimental to human and animal health. The production of such biological toxins is influenced by environmental factors including pollutants, such as dioxins. Here, we report the biological feedback of an active AF-producer strain of A. flavus upon in vitro exposure to the most toxic congener of dioxins, the 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (TCDD). The phenotype of TCDD-exposed A. flavus was typified by a severe limitation in vegetative growth, activation of conidia formation and a significant boost in AF production. Furthermore, the level of reactive oxygen species (ROS) in fungal protoplast was increased (3.1- to 3.8-fold) in response to TCDD exposure at 10 and 50 ng mL-1, respectively. In parallel, superoxide dismutase (SOD) and catalase (CAT) activities were, respectively, increased by a factor of 2 and 3. In contrast to controls, transcript, protein and enzymatic activity of caleosin/peroxygenase (AfPXG) was also significantly induced in TCDD-exposed fungi. Subsequently, fungal cells accumulated fivefold more lipid droplets (LDs) than controls. Moreover, the TCDD-exposed fungi exhibited twofold higher levels of AFB1. Interestingly, TCDD-induced hyperaflatoxicogenicity was drastically abolished in the AfPXG-silencing strain of A. flavus, suggesting a role for AfPXG in fungal response to TCDD. Finally, TCDD-exposed fungi showed an increased in vitro virulence in terms of sporulation and AF production. The data highlight the possible effects of dioxin on aflatoxicogenicity of A. flavus and suggest therefore that attention should be paid in particular to the potential consequences of climate change on global food safety.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria, Damascus, Syria
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17
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Hanano A, Shaban M, Almutlk D, Almousally I. The cytochrome P450 BM-1 of Bacillus megaterium A14K is induced by 2,3,7,8-Tetrachlorinated dibenzo-p-dioxin: Biophysical, molecular and biochemical determinants. CHEMOSPHERE 2019; 216:258-270. [PMID: 30384294 DOI: 10.1016/j.chemosphere.2018.10.103] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 10/10/2018] [Accepted: 10/16/2018] [Indexed: 06/08/2023]
Abstract
The current study describes biological changes in Bacillus megaterium A14K cells growing in the presence of 2,3,7,8-Tetrachlorinated dibenzo-p-dioxin (TCDD), the most potent congener of dioxins. The results indicate that the metabolizing of 2,3,7,8-TCDD by BmA14K was accompanied with a novel morphological and biophysical profile typified by the growth of single cells with high levels of biosurfactant production, surface hydrophobicity and cell membrane permeability. Moreover, the TCDD-grown bacteria exhibited a specific fatty acid profile characterized by low ratios of branched/straight chain fatty acids (BCFAs/SCFAs) and saturated/unsaturated fatty acids (SFAs/USFAs) with a specific "signature" due to the presence of branched chain unsaturated fatty acids (BCUFAs). This was synchronized with a significant induction of P450BM-1, an unsaturated fatty acid-metabolizing enzyme in B. megaterium. Subsequently, the profile of oxygenated fatty acids in the TCDD-grown bacteria was typified by the presence of 5,6-epoxy derived from unsaturated C15, C16 and C17 fatty acids, that were absent in control bacteria. A net increase was also detected in both hydroxylated and epoxidized fatty acids, especially those derived from C15:0 and C16:1, respectively, suggesting a specific TCDD-induced "signature" of oxygenated fatty acids in BmA14K. Overall, this study sheds light on the use of B. megaterium A14K as a promising bioindicator/biodegrader of dioxins.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria.
| | - Mouhnad Shaban
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria
| | - Douaa Almutlk
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria
| | - Ibrahem Almousally
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria
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18
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Rahman F, Hassan M, Hanano A, Fitzpatrick DA, McCarthy CGP, Murphy DJ. Evolutionary, structural and functional analysis of the caleosin/peroxygenase gene family in the Fungi. BMC Genomics 2018; 19:976. [PMID: 30593269 PMCID: PMC6309107 DOI: 10.1186/s12864-018-5334-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 11/29/2018] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Caleosin/peroxygenases, CLO/PXG, (designated PF05042 in Pfam) are a group of genes/proteins with anomalous distributions in eukaryotic taxa. We have previously characterised CLO/PXGs in the Viridiplantae. The aim of this study was to investigate the evolution and functions of the CLO/PXGs in the Fungi and other non-plant clades and to elucidate the overall origin of this gene family. RESULTS CLO/PXG-like genes are distributed across the full range of fungal groups from the basal clades, Cryptomycota and Microsporidia, to the largest and most complex Dikarya species. However, the genes were only present in 243 out of 844 analysed fungal genomes. CLO/PXG-like genes have been retained in many pathogenic or parasitic fungi that have undergone considerable genomic and structural simplification, indicating that they have important functions in these species. Structural and functional analyses demonstrate that CLO/PXGs are multifunctional proteins closely related to similar proteins found in all major taxa of the Chlorophyte Division of the Viridiplantae. Transcriptome and physiological data show that fungal CLO/PXG-like genes have complex patterns of developmental and tissue-specific expression and are upregulated in response to a range of biotic and abiotic stresses as well as participating in key metabolic and developmental processes such as lipid metabolism, signalling, reproduction and pathogenesis. Biochemical data also reveal that the Aspergillus flavus CLO/PXG has specific functions in sporulation and aflatoxin production as well as playing roles in lipid droplet function. CONCLUSIONS In contrast to plants, CLO/PXGs only occur in about 30% of sequenced fungal genomes but are present in all major taxa. Fungal CLO/PXGs have similar but not identical roles to those in plants, including stress-related oxylipin signalling, lipid metabolism, reproduction and pathogenesis. While the presence of CLO/PXG orthologs in all plant genomes sequenced to date would suggest that they have core housekeeping functions in plants, the selective loss of CLO/PXGs in many fungal genomes suggests more restricted functions in fungi as accessory genes useful in particular environments or niches. We suggest an ancient origin of CLO/PXG-like genes in the 'last eukaryotic common ancestor' (LECA) and their subsequent loss in ancestors of the Metazoa, after the latter had diverged from the ancestral fungal lineage.
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Affiliation(s)
- Farzana Rahman
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, CF37 1DL UK
| | - Mehedi Hassan
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, CF37 1DL UK
| | - Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus, Syria
| | | | | | - Denis J. Murphy
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, CF37 1DL UK
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19
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Lv C, Wang P, Ma L, Zheng M, Liu Y, Xing F. Large-Scale Comparative Analysis of Eugenol-Induced/Repressed Genes Expression in Aspergillus flavus Using RNA-seq. Front Microbiol 2018; 9:1116. [PMID: 29899734 PMCID: PMC5988903 DOI: 10.3389/fmicb.2018.01116] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/11/2018] [Indexed: 11/24/2022] Open
Abstract
Aflatoxin B1 (AFB1), which is mainly produced by Aspergillus flavus and Aspergillus parasiticus, is the most toxic and hepatocarcinogenic polyketide known. Chemical fungicides are currently utilized to reduce this fungal contaminant, but they are potentially harmful to human health and the environment. Therefore, natural anti-aflatoxigenic products are used as sustainable alternatives to control food and feed contamination. For example, eugenol, presents in many essential oils, has been identified as an aflatoxin inhibitor. However, its exact mechanism of inhibition is yet to be clarified. In this study, the anti-aflatoxigenic mechanism of eugenol in A. flavus was determined using a comparative transcriptomic approach. Twenty of twenty-nine genes in the aflatoxin biosynthetic pathway were down-regulated by eugenol. The most strongly down-regulated gene was aflMa, followed by aflI, aflJ, aflCa, aflH, aflNa, aflE, aflG, aflM, aflD, and aflP. However, the expression of the regulator gene aflR did not change significantly and the expression of aflS was slightly up-regulated. The down-regulation of the global regulator gene veA resulted in the up-regulation of srrA, and the down-regulation of ap-1 and mtfA. The early developmental regulator brlA was profoundly up-regulated in A. flavus after eugenol treatment. These results suggested a model in which eugenol improves fungal development by up-regulating the expression of brlA by the suppression of veA expression and inhibits aflatoxin production through the suppression of veA expression. Exposure to eugenol also caused dysregulated transcript levels of the G protein-coupled receptors (GPCRs) and oxylipins genes. A Gene Ontology analysis indicated that the genes that were highly responsive to eugenol were mainly enriched in RNA-binding functions, suggesting that post-transcriptional modification plays a pivotal role in aflatoxin biosynthesis. KEGG analysis showed that ribosome biogenesis was the most dysregulated pathway, suggesting that eugenol dysregulates ribosome biogenesis, which then interrupts the biosynthesis of Nor-1, Ver-1, and OmtA, and prevents aflatoxisomes performing their normal function in aflatoxin production. In conclusion, our results indicated that eugenol inhibited AFB1 production by modulating the expression of structural genes in aflatoxin pathway, fungal antioxidant status, post-transcriptional modifications and biosynthesis of backbone enzymes in A. flavus.
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Affiliation(s)
- Cong Lv
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing, China
| | - Ping Wang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing, China
| | - Longxue Ma
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing, China
| | - Mumin Zheng
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing, China
| | - Yang Liu
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing, China
| | - Fuguo Xing
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing, China
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