1
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Anand R, Kashif M, Pandit A, Babu R, Singh AP. Reprogramming in Candida albicans Gene Expression Network under Butanol Stress Abrogates Hyphal Development. Int J Mol Sci 2023; 24:17227. [PMID: 38139056 PMCID: PMC10743114 DOI: 10.3390/ijms242417227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 12/24/2023] Open
Abstract
Candida albicans is the causative agent of invasive fungal infections. Its hyphae-forming ability is regarded as one of the important virulence factors. To unravel the impact of butanol on Candida albicans, it was placed in O+ve complete human serum with butanol (1% v/v). The Candida transcriptome under butanol stress was then identified by mRNA sequencing. Studies including electron microscopy demonstrated the inhibition of hyphae formation in Candida under the influence of butanol, without any significant alteration in growth rate. The numbers of genes upregulated in the butanol in comparison to the serum alone were 1061 (20 min), 804 (45 min), and 537 (120 min). Candida cells exhibited the downregulation of six hypha-specific transcription factors and the induction of four repressor/regulator genes. Many of the hypha-specific genes exhibited repression in the medium with butanol. The genes related to adhesion also exhibited repression, whereas, among the heat-shock genes, three showed inductions in the presence of butanol. The fungal-specific genes exhibited induction as well as repression in the butanol-treated Candida cells. Furthermore, ten upregulated genes formed the core stress gene set in the presence of butanol. In the gene ontology analysis, enrichment of the processes related to non-coding RNA, ribosome biosynthesis, and metabolism was observed in the induced gene set. On the other side, a few GO biological process terms, including biofilm formation and filamentous growth, were enriched in the repressed gene set. Taken together, under butanol stress, Candida albicans is unable to extend hyphae and shows growth by budding. Many of the genes with perturbed expression may have fitness or virulence attributes and may provide prospective sites of antifungal targets against C. albicans.
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Affiliation(s)
- Rajesh Anand
- Infectious Disease Laboratory, National Institute of Immunology, New Delhi 110067, India; (R.A.)
| | - Mohammad Kashif
- Infectious Disease Laboratory, National Institute of Immunology, New Delhi 110067, India; (R.A.)
| | - Awadhesh Pandit
- Next Generation Sequencing Facility, National Institute of Immunology, New Delhi 110067, India
| | - Ram Babu
- Department of Botany, Kirori Mal College, University of Delhi, Delhi 110007, India
| | - Agam P. Singh
- Infectious Disease Laboratory, National Institute of Immunology, New Delhi 110067, India; (R.A.)
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2
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Speer NO, Braun RJ, Reynolds E, Brudnicka A, Swanson J, Henne WM. Tld1 is a novel regulator of triglyceride lipolysis that demarcates a lipid droplet subpopulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.07.531595. [PMID: 36945645 PMCID: PMC10028886 DOI: 10.1101/2023.03.07.531595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Cells store lipids in the form of triglyceride (TG) and sterol-ester (SE) in lipid droplets (LDs). Distinct pools of LDs exist, but a pervasive question is how proteins localize to and convey functions to LD subsets. Here, we show the yeast protein YDR275W/Tld1 (for TG-associated LD protein 1) localizes to a subset of TG-containing LDs, and reveal it negatively regulates lipolysis. Mechanistically, Tld1 LD targeting requires TG, and is mediated by two distinct hydrophobic regions (HRs). Molecular dynamics simulations reveal Tld1 HRs interact with TG on LDs and adopt specific conformations on TG-rich LDs versus SE-rich LDs in yeast and human cells. Tld1-deficient yeast display no defect in LD biogenesis, but exhibit elevated TG lipolysis dependent on lipase Tgl3. Remarkably, over-expression of Tld1, but not LD protein Pln1/Pet10, promotes TG accumulation without altering SE pools. Finally, we find Tld1-deficient cells display altered LD mobilization during extended yeast starvation. We propose Tld1 senses TG-rich LDs and regulates lipolysis on LD subpopulations.
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3
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Wu S, Zhang YF, Gui Y, Jiang T, Zhou CM, Li JY, Suo JL, Li YN, Jin RL, Li SL, Cui JY, Tan BH, Li YC. A detection method for neuronal death indicates abnormalities in intracellular membranous components in neuronal cells that underwent delayed death. Prog Neurobiol 2023; 226:102461. [PMID: 37179048 DOI: 10.1016/j.pneurobio.2023.102461] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 03/20/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023]
Abstract
Acute neuronal degeneration is always preceded under the light and electron microscopes by a stage called microvacuolation, which is characterized by a finely vacuolar alteration in the cytoplasm of the neurons destined to death. In this study, we reported a method for detecting neuronal death using two membrane-bound dyes, rhodamine R6 and DiOC6(3), which may be associated with the so-called microvacuolation. This new method produced a spatiotemporally similar staining pattern to Fluoro-Jade B in kainic acid-damaged brains in mice. Further experiments showed that increased staining of rhodamine R6 and DiOC6(3) was observed only in degenerated neurons, but not in glia, erythrocytes, or meninges. Different from Fluoro-Jade-related dyes, rhodamine R6 and DiOC6(3) staining is highly sensitive to solvent extraction and detergent exposure. Staining with Nile red for phospholipids and filipin III for non-esterified cholesterol supports that the increased staining of rhodamine R6 and DiOC6(3) might be associated with increased levels of phospholipids and free cholesterol in the perinuclear cytoplasm of damaged neurons. In addition to kainic acid-injected neuronal death, rhodamine R6 and DiOC6(3) were similarly useful for detecting neuronal death in ischemic models either in vivo or in vitro. As far as we know, the staining with rhodamine R6 or DiOC6(3) is one of a few histochemical methods for detecting neuronal death whose target molecules have been well defined and therefore may be useful for explaining experimental results as well as exploring the mechanisms of neuronal death. (250 words).
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Affiliation(s)
- Shuang Wu
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Yan-Feng Zhang
- Department of Pediatric Neurology, First Hospital of Jilin University, Changchun, Jilin Province 130021, PR China
| | - Yue Gui
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Tian Jiang
- Department of Emergency and Critical Care Medicine, The Second Hospital of Jilin University, Jilin Province 130041, PR China
| | - Cheng-Mei Zhou
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Jing-Yi Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Jia-Le Suo
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Yong-Nan Li
- Department of Neurology, Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province 150001, PR China
| | - Rui-Lin Jin
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Shu-Lei Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Jia-Yue Cui
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Bai-Hong Tan
- Laboratory Teaching Center of Basic Medicine, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Yan-Chao Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China.
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4
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Peng G, Hu K, Shang X, Li W, Dou F. The phosphorylation status of Hsp82 regulates mitochondrial homeostasis during glucose sensing in Saccharomyces cerevisiae. J Mol Biol 2023; 435:168106. [PMID: 37068581 DOI: 10.1016/j.jmb.2023.168106] [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: 11/17/2022] [Revised: 04/11/2023] [Accepted: 04/11/2023] [Indexed: 04/19/2023]
Abstract
Sensing extracellular glucose, budding yeast switches from aerobic glycolysis to oxidative phosphorylation to adapt to environmental changes. During the conversion of metabolic mode, mitochondrial function and morphology change significantly. Mitochondria are the main supply factories of energy for various life activities in cells. However, the research on the signal pathways from glucose sensing to changes in mitochondrial function and morphology is still scarce and worthy of further exploration. In this study, we found that in addition to the known involvement of molecular chaperone Hsp82 in stress response during the conversion of metabolic mode, the phosphorylation status of Hsp82 at S485 residue regulates mitochondrial function and morphology to maintain mitochondrial homeostasis. The Hsp82S485A mutant that mimics dephosphorylation at S485 residue showed abnormal growth phenotypes related to mitochondrial defects, such as the petite phenotype, slow growth rates, and inability to use non-fermentable carbon sources. Further exploring the causes of growth defects, we found that the Hsp82S485A mutant caused mitochondrial dysfunction, including a decrease in cellular oxygen consumption rate, defects in mitochondrial electron transport chain, decreased mitochondrial membrane potential and complete loss of mtDNA. Furthermore, the Hsp82S485A mutant displayed fragmented or globular mitochondria, which may be responsible for its mitochondrial dysfunction. Our findings suggested that the phosphorylation status of Hsp82 at S485 residue might regulate mitochondrial function and morphology by affecting the stability of mitochondrial fission and fusion-related proteins. Thus, Hsp82 might be a key molecule in the signal pathway from glucose sensing to changes in mitochondrial function and morphology.
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Affiliation(s)
- Guanzu Peng
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Kaiyu Hu
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Xuan Shang
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Wanjie Li
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China.
| | - Fei Dou
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China.
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5
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Mrazova K, Bacovsky J, Sedrlova Z, Slaninova E, Obruca S, Fritz I, Krzyzanek V. Urany-Less Low Voltage Transmission Electron Microscopy: A Powerful Tool for Ultrastructural Studying of Cyanobacterial Cells. Microorganisms 2023; 11:888. [PMID: 37110311 PMCID: PMC10146862 DOI: 10.3390/microorganisms11040888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
Sample preparation protocols for conventional high voltage transmission electron microscopy (TEM) heavily rely on the usage of staining agents containing various heavy metals, most commonly uranyl acetate and lead citrate. However high toxicity, rising legal regulations, and problematic waste disposal of uranyl acetate have increased calls for the reduction or even complete replacement of this staining agent. One of the strategies for uranyless imaging is the employment of low-voltage transmission electron microscopy. To investigate the influence of different imaging and staining strategies on the final image of cyanobacterial cells, samples stained by uranyl acetate with lead citrate, as well as unstained samples, were observed using TEM and accelerating voltages of 200 kV or 25 kV. Moreover, to examine the possibilities of reducing chromatic aberration, which often causes issues when imaging using electrons of lower energies, samples were also imaged using a scanning transmission electron microscopy at 15 kV accelerating voltages. The results of this study demonstrate that low-voltage electron microscopy offers great potential for uranyless electron microscopy.
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Affiliation(s)
- Katerina Mrazova
- Institute of Scientific Instruments of the Czech Academy of Sciences, v.v.i., Kralovopolska 147, 612 64 Brno, Czech Republic;
| | - Jaromir Bacovsky
- Delong Instruments a.s., Palackeho Trida 3019/153 b, 612 00 Brno, Czech Republic;
| | - Zuzana Sedrlova
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (Z.S.); (E.S.); (S.O.)
| | - Eva Slaninova
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (Z.S.); (E.S.); (S.O.)
| | - Stanislav Obruca
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (Z.S.); (E.S.); (S.O.)
| | - Ines Fritz
- Institute of Environmental Biotechnology, Department of Agrobiotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Konrad-Lorenz-Strase 20, 3430 Tulln an der Donau, Austria;
| | - Vladislav Krzyzanek
- Institute of Scientific Instruments of the Czech Academy of Sciences, v.v.i., Kralovopolska 147, 612 64 Brno, Czech Republic;
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6
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Tan L, Liu X, Zhang Y. Glutaraldehyde fixation promotes palladium and gold nanoparticles formation in yeast and enhances their catalytic activity in 4-nitrophenol reduction. JOURNAL OF HAZARDOUS MATERIALS 2023; 446:130696. [PMID: 36603424 DOI: 10.1016/j.jhazmat.2022.130696] [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: 09/20/2022] [Revised: 11/26/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
When observing biosynthesized metal nanoparticles in microorganisms, glutaraldehyde is commonly used as a fixative to prepare TEM ultra-thin sections. However, as a chemical reagent with aldehyde groups, its reduction potential on metal ions has yet to be studied elaborately. Herein, we explored the influences of glutaraldehyde on yeast-synthesized gold nanoparticles (AuNPs), palladium nanoparticles (PdNPs) and their catalytic performance. A modified method for ultra-thin section preparation without glutaraldehyde fixation was developed to exclude its influence on AuNPs/PdNPs observation. It was confirmed that glutaraldehyde could promote the biosynthesis of AuNPs and PdNPs extra- and intracellularly, without altering their crystal structure and chemical state. The adsorption and reduction of Au(III)/Pd(II) were attributed to the different components of the yeast cell. Specifically, the amines and carboxyl groups in proteins and polysaccharides were involved in adsorption, while the reducing sugars hydrolyzed from polysaccharides were responsible for Au(III)/Pd(II) reduction. After glutaraldehyde fixation, the catalytic activities of Au/Pd-loaded yeast in 4-nitrophenol reduction were enhanced as well. Therefore, the influence of chemical fixatives in biosynthesized metal nanoparticles should be taken into consideration in regard to SEM, TEM observation and catalytic performance.
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Affiliation(s)
- Ling Tan
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China
| | - Xindi Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China
| | - Yanfei Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China.
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7
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Milholland KL, AbdelKhalek A, Baker KM, Hoda S, DeMarco AG, Naughton NH, Koeberlein AN, Lorenz GR, Anandasothy K, Esperilla-Muñoz A, Narayanan SK, Correa-Bordes J, Briggs SD, Hall MC. Cdc14 phosphatase contributes to cell wall integrity and pathogenesis in Candida albicans. Front Microbiol 2023; 14:1129155. [PMID: 36876065 PMCID: PMC9977832 DOI: 10.3389/fmicb.2023.1129155] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 01/26/2023] [Indexed: 02/18/2023] Open
Abstract
The Cdc14 phosphatase family is highly conserved in fungi. In Saccharomyces cerevisiae, Cdc14 is essential for down-regulation of cyclin-dependent kinase activity at mitotic exit. However, this essential function is not broadly conserved and requires only a small fraction of normal Cdc14 activity. Here, we identified an invariant motif in the disordered C-terminal tail of fungal Cdc14 enzymes that is required for full enzyme activity. Mutation of this motif reduced Cdc14 catalytic rate and provided a tool for studying the biological significance of high Cdc14 activity. A S. cerevisiae strain expressing the reduced-activity hypomorphic mutant allele (cdc14hm ) as the sole source of Cdc14 proliferated like the wild-type parent strain but exhibited an unexpected sensitivity to cell wall stresses, including chitin-binding compounds and echinocandin antifungal drugs. Sensitivity to echinocandins was also observed in Schizosaccharomyces pombe and Candida albicans strains lacking CDC14, suggesting this phenotype reflects a novel and conserved function of Cdc14 orthologs in mediating fungal cell wall integrity. In C. albicans, the orthologous cdc14hm allele was sufficient to elicit echinocandin hypersensitivity and perturb cell wall integrity signaling. It also caused striking abnormalities in septum structure and the same cell separation and hyphal differentiation defects previously observed with cdc14 gene deletions. Since hyphal differentiation is important for C. albicans pathogenesis, we assessed the effect of reduced Cdc14 activity on virulence in Galleria mellonella and mouse models of invasive candidiasis. Partial reduction in Cdc14 activity via cdc14hm mutation severely impaired C. albicans virulence in both assays. Our results reveal that high Cdc14 activity is important for C. albicans cell wall integrity and pathogenesis and suggest that Cdc14 may be worth future exploration as an antifungal drug target.
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Affiliation(s)
- Kedric L Milholland
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Ahmed AbdelKhalek
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, United States
| | - Kortany M Baker
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Smriti Hoda
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Andrew G DeMarco
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Noelle H Naughton
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Angela N Koeberlein
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Gabrielle R Lorenz
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Kartikan Anandasothy
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | | | - Sanjeev K Narayanan
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, United States
| | - Jaime Correa-Bordes
- Department of Biomedical Sciences, Universidad de Extremadura, Badajoz, Spain
| | - Scott D Briggs
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States.,Institute for Cancer Research, Purdue University, West Lafayette, IN, United States
| | - Mark C Hall
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States.,Institute for Cancer Research, Purdue University, West Lafayette, IN, United States
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8
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Ochoa-Gutiérrez D, Reyes-Torres AM, de la Fuente-Colmenares I, Escobar-Sánchez V, González J, Ortiz-Hernández R, Torres-Ramírez N, Segal-Kischinevzky C. Alternative CUG Codon Usage in the Halotolerant Yeast Debaryomyces hansenii: Gene Expression Profiles Provide New Insights into Ambiguous Translation. J Fungi (Basel) 2022; 8:jof8090970. [PMID: 36135695 PMCID: PMC9502446 DOI: 10.3390/jof8090970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/10/2022] [Accepted: 09/12/2022] [Indexed: 12/04/2022] Open
Abstract
The halotolerant yeast Debaryomyces hansenii belongs to the CTG-Ser1 clade of fungal species that use the CUG codon to translate as leucine or serine. The ambiguous decoding of the CUG codon is relevant for expanding protein diversity, but little is known about the role of leucine–serine ambiguity in cellular adaptations to extreme environments. Here, we examine sequences and structures of tRNACAG from the CTG-Ser1 clade yeasts, finding that D. hansenii conserves the elements to translate ambiguously. Then, we show that D. hansenii has tolerance to conditions of salinity, acidity, alkalinity, and oxidative stress associated with phenotypic and ultrastructural changes. In these conditions, we found differential expression in both the logarithmic and stationary growth phases of tRNASer, tRNALeu, tRNACAG, LeuRS, and SerRS genes that could be involved in the adaptive process of this yeast. Finally, we compare the proteomic isoelectric points and hydropathy profiles, detecting that the most important variations among the physicochemical characteristics of D. hansenii proteins are in their hydrophobic and hydrophilic interactions with the medium. We propose that the ambiguous translation, i.e., leucylation or serynation, on translation of the CUG-encoded residues, could be linked to adaptation processes in extreme environments.
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Affiliation(s)
- Daniel Ochoa-Gutiérrez
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Anya M. Reyes-Torres
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Ileana de la Fuente-Colmenares
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Viviana Escobar-Sánchez
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - James González
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Rosario Ortiz-Hernández
- Laboratorio de Microscopía Electrónica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Nayeli Torres-Ramírez
- Laboratorio de Microscopía Electrónica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Claudia Segal-Kischinevzky
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
- Correspondence:
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9
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Yue H, Xu X, He S, Cui X, Guo Y, Zhao J, Peng B, Liu Q. Antifungal Mechanisms of a Chinese Herbal Medicine, Cao Huang Gui Xiang, Against Candida Species. Front Pharmacol 2022; 13:813818. [PMID: 35355715 PMCID: PMC8959912 DOI: 10.3389/fphar.2022.813818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/07/2022] [Indexed: 11/13/2022] Open
Abstract
Cao Huang Gui Xiang (CHGX) formula, a Chinese herbal medicine, has been empirically used for the treatment of Candida infections. In the present study, we discovered that the CHGX showed potent antifungal activities against the major human fungal pathogen Candida albicans and other clinical Candida species. Besides, we indicated that CHGX had in vivo efficacy on treating C. albicans infection in mice without noticeable toxicity at the clinical therapeutic concentration. We then set out to investigate the antifungal mechanisms of CHGX against C. albicans. We found that CHGX played an important role in inhibiting biofilm formation and filament development, two critical virulence factors of C. albicans. We further demonstrated that CHGX disrupted cell membrane integrity, triggered the accumulation of reactive oxygen species (ROS) and consumption of adenosine triphosphate (ATP), followed by a rapid fungal cell death in C. albicans. Multiple pathways, including the conserved Ras1-cAMP pathway and mitochondrial protein Mcu1 are involved in CHGX-induced cell death. Our finding expands the understanding of antifungal mechanism of CHGX against C. albicans, and provides new insights in treating patients with Candida infections in clinical practice.
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Affiliation(s)
- Huizhen Yue
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
| | - Xiaolong Xu
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
| | - Shasha He
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
| | - Xuran Cui
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
| | - Yuhong Guo
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
| | - Jingxia Zhao
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
| | - Bing Peng
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China
| | - Qingquan Liu
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.,Beijing Institute of Chinese Medicine, Beijing, China.,Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases, Beijing, China
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10
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Wang Y, Li J, Zhao F, Zhang Y, Yang X, Lin Y, Han S. Methanol oxidase from Hansenula polymorpha shows activity in peroxisome-deficient Pichia pastoris. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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11
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Schauflinger M, Bergner T, Neusser G, Kranz C, Read C. Potassium permanganate is an excellent alternative to osmium tetroxide in freeze-substitution. Histochem Cell Biol 2022; 157:481-489. [PMID: 34984524 PMCID: PMC9001235 DOI: 10.1007/s00418-021-02070-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/24/2021] [Indexed: 11/06/2022]
Abstract
High-pressure freezing followed by freeze-substitution is a valuable method for ultrastructural analyses of resin-embedded biological samples. The visualization of lipid membranes is one of the most critical aspects of any ultrastructural study and can be especially challenging in high-pressure frozen specimens. Historically, osmium tetroxide has been the preferred fixative and staining agent for lipid-containing structures in freeze-substitution solutions. However, osmium tetroxide is not only a rare and expensive material, but also volatile and toxic. Here, we introduce the use of a combination of potassium permanganate, uranyl acetate, and water in acetone as complementing reagents during the freeze-substitution process. This mix imparts an intense en bloc stain to cellular ultrastructure and membranes, which makes poststaining superfluous and is well suited for block-face imaging. Thus, potassium permanganate can effectively replace osmium tetroxide in the freeze-substitution solution without sacrificing the quality of ultrastructural preservation.
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Affiliation(s)
- Martin Schauflinger
- Institute of Virology, Philipps University Marburg, Hans-Meerwein-Straße 2, 35037, Marburg, Germany. .,Electron Microscopy Core Facility, University of Missouri, 1600 East Rollins Street, Columbia, MO, 65211, USA.
| | - Tim Bergner
- Central Facility for Electron Microscopy, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Gregor Neusser
- FIB Center UUlm, Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Christine Kranz
- FIB Center UUlm, Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Clarissa Read
- Central Facility for Electron Microscopy, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.,Institute of Virology, Ulm University Medical Center, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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12
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Gok MO, Speer NO, Henne WM, Friedman JR. ER-localized phosphatidylethanolamine synthase plays a conserved role in lipid droplet formation. Mol Biol Cell 2022; 33:ar11. [PMID: 34818062 PMCID: PMC8886813 DOI: 10.1091/mbc.e21-11-0558-t] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The asymmetric distribution of phospholipids in membranes is a fundamental principle of cellular compartmentalization and organization. Phosphatidylethanolamine (PE), a nonbilayer phospholipid that contributes to organelle shape and function, is synthesized at several subcellular localizations via semiredundant pathways. Previously, we demonstrated in budding yeast that the PE synthase Psd1, which primarily operates on the mitochondrial inner membrane, is additionally targeted to the ER. While ER-localized Psd1 is required to support cellular growth in the absence of redundant pathways, its physiological function is unclear. We now demonstrate that ER-localized Psd1 sublocalizes on the ER to lipid droplet (LD) attachment sites and show it is specifically required for normal LD formation. We also find that the role of phosphatidylserine decarboxylase (PSD) enzymes in LD formation is conserved in other organisms. Thus we have identified PSD enzymes as novel regulators of LDs and demonstrate that both mitochondria and LDs in yeast are organized and shaped by the spatial positioning of a single PE synthesis enzyme.
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Affiliation(s)
- Mehmet Oguz Gok
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Natalie Ortiz Speer
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - W Mike Henne
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jonathan R Friedman
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
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13
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Fiołka MJ, Czaplewska P, Wójcik-Mieszawska S, Lewandowska A, Lewtak K, Sofińska-Chmiel W, Buchwald T. Metabolic, structural, and proteomic changes in Candida albicans cells induced by the protein-carbohydrate fraction of Dendrobaena veneta coelomic fluid. Sci Rep 2021; 11:16711. [PMID: 34408181 PMCID: PMC8373886 DOI: 10.1038/s41598-021-96093-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/02/2021] [Indexed: 01/14/2023] Open
Abstract
The isolated protein-polysaccharide fraction (AAF) from the coelomic fluid of Dendrobaena veneta earthworm shows effective activity against Candida albicans yeast. Fungal cells of the clinical strain after incubation with the active fraction were characterized by disturbed cell division and different morphological forms due to the inability to separate the cells from each other. Staining of the cells with acridine orange revealed a change in the pH of the AAF-treated cells. It was observed that, after the AAF treatment, the mitochondrial DNA migrated towards the nuclear DNA, whereupon both merged into a single nuclear structure, which preceded the apoptotic process. Cells with a large nucleus were imaged with the scanning electron cryomicroscopy (Cryo-SEM) technique, while enlarged mitochondria and the degeneration of cell structures were shown by transmission electron microscopy (TEM). The loss of the correct cell shape and cell wall integrity was visualized by both the TEM and SEM techniques. Mass spectrometry and relative quantitative SWATH MS analysis were used to determine the reaction of the C. albicans proteome to the components of the AAF fraction. AAF was observed to influence the expression of mitochondrial and oxidative stress proteins. The oxidative stress in C. albicans cells caused by the action of AAF was demonstrated by fluorescence microscopy, proteomic methods, and XPS spectroscopy. The secondary structure of AAF proteins was characterized by Raman spectroscopy. Analysis of the elemental composition of AAF confirmed the homogeneity of the preparation. The observed action of AAF, which targets not only the cell wall but also the mitochondria, makes the preparation a potential antifungal drug killing the cells of the C. albicans pathogen through apoptosis.
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Affiliation(s)
- Marta J Fiołka
- Department of Immunobiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033, Lublin, Poland.
| | - Paulina Czaplewska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Sylwia Wójcik-Mieszawska
- Department of Immunobiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033, Lublin, Poland
| | - Aleksandra Lewandowska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Kinga Lewtak
- Department of Cell Biology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Weronika Sofińska-Chmiel
- Analytical Laboratory, Institute of Chemical Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Tomasz Buchwald
- Faculty of Materials Science and Technical Physics, Institute of Materials Research and Quantum Engineering, Poznan University of Technology, Poznań, Poland
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14
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Molenaar MR, Yadav KK, Toulmay A, Wassenaar TA, Mari MC, Caillon L, Chorlay A, Lukmantara IE, Haaker MW, Wubbolts RW, Houweling M, Vaandrager AB, Prieur X, Reggiori F, Choudhary V, Yang H, Schneiter R, Thiam AR, Prinz WA, Helms JB. Retinyl esters form lipid droplets independently of triacylglycerol and seipin. J Cell Biol 2021; 220:212517. [PMID: 34323918 PMCID: PMC8327380 DOI: 10.1083/jcb.202011071] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 05/21/2021] [Accepted: 07/07/2021] [Indexed: 11/23/2022] Open
Abstract
Lipid droplets store neutral lipids, primarily triacylglycerol and steryl esters. Seipin plays a role in lipid droplet biogenesis and is thought to determine the site of lipid droplet biogenesis and the size of newly formed lipid droplets. Here we show a seipin-independent pathway of lipid droplet biogenesis. In silico and in vitro experiments reveal that retinyl esters have the intrinsic propensity to sequester and nucleate in lipid bilayers. Production of retinyl esters in mammalian and yeast cells that do not normally produce retinyl esters causes the formation of lipid droplets, even in a yeast strain that produces only retinyl esters and no other neutral lipids. Seipin does not determine the size or biogenesis site of lipid droplets composed of only retinyl esters or steryl esters. These findings indicate that the role of seipin in lipid droplet biogenesis depends on the type of neutral lipid stored in forming droplets.
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Affiliation(s)
- Martijn R Molenaar
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Kamlesh K Yadav
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Alexandre Toulmay
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Tsjerk A Wassenaar
- Groningen Biomolecular Sciences and Biotechnology Institute, Zernike Institute for Advanced Materials, University of Groningen, Groningen, Netherlands
| | - Muriel C Mari
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Lucie Caillon
- Laboratoire de Physique Statistique, Ecole Normale Supérieure, Paris Sciences et Lettres Research University, Sorbonne Université, Université Pierre-et-Marie-Curie Université Paris 06, Université Paris Diderot, Centre national de la recherche scientifique, Paris, France
| | - Aymeric Chorlay
- Laboratoire de Physique Statistique, Ecole Normale Supérieure, Paris Sciences et Lettres Research University, Sorbonne Université, Université Pierre-et-Marie-Curie Université Paris 06, Université Paris Diderot, Centre national de la recherche scientifique, Paris, France
| | - Ivan E Lukmantara
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Maya W Haaker
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Richard W Wubbolts
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Martin Houweling
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Arie Bas Vaandrager
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Xavier Prieur
- Université de Nantes, Centre national de la recherche scientifique, Institut national de la santé et de la recherche médicale, l'institut du thorax, Nantes, France
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Vineet Choudhary
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Roger Schneiter
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Abdou Rachid Thiam
- Laboratoire de Physique Statistique, Ecole Normale Supérieure, Paris Sciences et Lettres Research University, Sorbonne Université, Université Pierre-et-Marie-Curie Université Paris 06, Université Paris Diderot, Centre national de la recherche scientifique, Paris, France
| | - William A Prinz
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - J Bernd Helms
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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15
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Steele E, Alebous HD, Vickers M, Harris ME, Johnson MD. Co-culturing experiments reveal the uptake of myo-inositol phosphate synthase (EC 5.5.1.4) in an inositol auxotroph of Saccharomyces cerevisiae. Microb Cell Fact 2021; 20:138. [PMID: 34281557 PMCID: PMC8287684 DOI: 10.1186/s12934-021-01610-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 06/08/2021] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Myo-Inositol Phosphate Synthase (MIP) catalyzes the conversion of glucose 6- phosphate into inositol phosphate, an essential nutrient and cell signaling molecule. Data obtained, first in bovine brain and later in plants, established MIP expression in organelles and in extracellular environments. A physiological role for secreted MIP has remained elusive since its first detection in intercellular space. To provide further insight into the role of MIP in intercellular milieus, we tested the hypothesis that MIP may function as a growth factor, synthesizing inositol phosphate in intercellular locations requiring, but lacking ability to produce or transport adequate quantities of the cell-cell communicator. This idea was experimentally challenged, utilizing a Saccharomyces cerevisiae inositol auxotroph with no MIP enzyme, permeable membranes with a 0.4 µm pore size, and cellular supernatants as external sources of inositol isolated from S. cerevisiae cells containing either wild-type enzyme (Wt-MIP), no MIP enzyme, auxotroph (Aux), or a green fluorescent protein (GFP) tagged reporter enzyme (MIP- GFP) in co- culturing experiments. RESULTS Resulting cell densities and microscopic studies with corroborating biochemical and molecular analyses, documented sustained growth of Aux cells in cellular supernatant, concomitant with the uptakeof MIP, detected as MIP-GFP reporter enzyme. These findings revealed previously unknown functions, suggesting that the enzyme can: (1) move into and out of intercellular space, (2) traverse cell walls, and (3) act as a growth factor to promote cellular proliferation of an inositol requiring cell. CONCLUSIONS Co-culturing experiments, designed to test a probable function for MIP secreted in extracellular vesicles, uncovered previously unknown functions for the enzyme and advanced current knowledge concerning spatial control of inositol phosphate biosynthesis. Most importantly, resulting data identified an extracellular vesicle (a non-viral vector) that is capable of synthesizing and transporting inositol phosphate, a biological activity that can be used to enhance specificity of current inositol phosphate therapeutics.
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Affiliation(s)
- Erika Steele
- The University of Alabama, The Institute of Social Science Research, PO Box 8702161, Tuscaloosa, AL 35487 USA
| | - Hana D. Alebous
- Department of Biological Sciences, School of Science, The University of Jordan, PO Box 11942, Amman-Jordan, Jordan
| | - Macy Vickers
- Department of Biological Sciences, The University of Alabama, PO Box 870344, Tuscaloosa, AL 35487 USA
| | - Mary E. Harris
- Department of Biological Sciences, The University of Alabama, PO Box 870344, Tuscaloosa, AL 35487 USA
| | - Margaret D. Johnson
- Department of Biological Sciences, The University of Alabama, PO Box 870344, Tuscaloosa, AL 35487 USA
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16
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Ren Q, Brenner R, Boothby TC, Zhang Z. Membrane and lipid metabolism plays an important role in desiccation resistance in the yeast Saccharomyces cerevisiae. BMC Microbiol 2020; 20:338. [PMID: 33167888 PMCID: PMC7653879 DOI: 10.1186/s12866-020-02025-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/28/2020] [Indexed: 12/23/2022] Open
Abstract
Background Anhydrobiotes, such as the yeast Saccharomyces cerevisiae, are capable of surviving almost total loss of water. Desiccation tolerance requires an interplay of multiple events, including preserving the protein function and membrane integrity, preventing and mitigating oxidative stress, maintaining certain level of energy required for cellular activities in the desiccated state. Many of these crucial processes can be controlled and modulated at the level of organelle morphology and dynamics. However, little is understood about what organelle perturbations manifest in desiccation-sensitive cells as a consequence of drying or how this differs from organelle biology in desiccation-tolerant organisms undergoing anhydrobiosis. Results In this study, electron and optical microscopy was used to examine the dynamic changes of yeast cells during the desiccation process. Dramatic structural changes were observed during the desiccation process, including the diminishing of vacuoles, decrease of lipid droplets, decrease in mitochondrial cristae and increase of ER membrane, which is likely caused by ER stress and unfolded protein response. The survival rate was significantly decreased in mutants that are defective in lipid droplet biosynthesis, or cells treated with cerulenin, an inhibitor of fatty acid synthesis. Conclusion Our study suggests that the metabolism of lipid droplets and membrane may play an important role in yeast desiccation tolerance by providing cells with energy and possibly metabolic water. Additionally, the decrease in mitochondrial cristae coupled with a decrease in lipid droplets is indicative of a cellular response to reduce the production of reactive oxygen species.
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Affiliation(s)
- Qun Ren
- Department of Zoology and Physiology, University of Wyoming, 1000 E. University Ave, Laramie, WY, 82071, USA
| | - Rebecca Brenner
- Department of Zoology and Physiology, University of Wyoming, 1000 E. University Ave, Laramie, WY, 82071, USA
| | - Thomas C Boothby
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA
| | - Zhaojie Zhang
- Department of Zoology and Physiology, University of Wyoming, 1000 E. University Ave, Laramie, WY, 82071, USA.
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17
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Yap WS, Shyu P, Gaspar ML, Jesch SA, Marvalim C, Prinz WA, Henry SA, Thibault G. The yeast FIT2 homologs are necessary to maintain cellular proteostasis and membrane lipid homeostasis. J Cell Sci 2020; 133:jcs248526. [PMID: 33033181 PMCID: PMC7657468 DOI: 10.1242/jcs.248526] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 10/01/2020] [Indexed: 12/12/2022] Open
Abstract
Lipid droplets (LDs) are implicated in conditions of lipid and protein dysregulation. The fat storage-inducing transmembrane (FIT; also known as FITM) family induces LD formation. Here, we establish a model system to study the role of the Saccharomyces cerevisiae FIT homologues (ScFIT), SCS3 and YFT2, in the proteostasis and stress response pathways. While LD biogenesis and basal endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) remain unaltered in ScFIT mutants, SCS3 was found to be essential for proper stress-induced UPR activation and for viability in the absence of the sole yeast UPR transducer IRE1 Owing to not having a functional UPR, cells with mutated SCS3 exhibited an accumulation of triacylglycerol within the ER along with aberrant LD morphology, suggesting that there is a UPR-dependent compensatory mechanism that acts to mitigate lack of SCS3 Additionally, SCS3 was necessary to maintain phospholipid homeostasis. Strikingly, global protein ubiquitylation and the turnover of both ER and cytoplasmic misfolded proteins is impaired in ScFITΔ cells, while a screen for interacting partners of Scs3 identifies components of the proteostatic machinery as putative targets. Together, our data support a model where ScFITs play an important role in lipid metabolism and proteostasis beyond their defined roles in LD biogenesis.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Wei Sheng Yap
- School of Biological Sciences Nanyang Technological University, Singapore, 637551
| | - Peter Shyu
- School of Biological Sciences Nanyang Technological University, Singapore, 637551
| | - Maria Laura Gaspar
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Stephen A Jesch
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Charlie Marvalim
- School of Biological Sciences Nanyang Technological University, Singapore, 637551
| | - William A Prinz
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Susan A Henry
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Guillaume Thibault
- School of Biological Sciences Nanyang Technological University, Singapore, 637551
- Institute of Molecular and Cell Biology, A*STAR, Singapore, 138673
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18
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Yang X, Zhang W, Wen X, Bulinski PJ, Chomchai DA, Arines FM, Liu YY, Sprenger S, Teis D, Klionsky DJ, Li M. TORC1 regulates vacuole membrane composition through ubiquitin- and ESCRT-dependent microautophagy. J Cell Biol 2020; 219:133713. [PMID: 32045480 PMCID: PMC7055007 DOI: 10.1083/jcb.201902127] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 11/22/2019] [Accepted: 01/07/2020] [Indexed: 01/12/2023] Open
Abstract
Cellular adaptation in response to nutrient limitation requires the induction of autophagy and lysosome biogenesis for the efficient recycling of macromolecules. Here, we discovered that starvation and TORC1 inactivation not only lead to the up-regulation of autophagy and vacuole proteins involved in recycling but also result in the down-regulation of many vacuole membrane proteins to supply amino acids as part of a vacuole remodeling process. Down-regulation of vacuole membrane proteins is initiated by ubiquitination, which is accomplished by the coordination of multiple E3 ubiquitin ligases, including Rsp5, the Dsc complex, and a newly characterized E3 ligase, Pib1. The Dsc complex is negatively regulated by TORC1 through the Rim15-Ume6 signaling cascade. After ubiquitination, vacuole membrane proteins are sorted into the lumen for degradation by ESCRT-dependent microautophagy. Thus, our study uncovered a complex relationship between TORC1 inactivation and vacuole biogenesis.
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Affiliation(s)
- Xi Yang
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Weichao Zhang
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Xin Wen
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI.,Life Sciences Institute, University of Michigan, Ann Arbor, MI
| | - Patrick J Bulinski
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Dominic A Chomchai
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Felichi Mae Arines
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Yun-Yu Liu
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Simon Sprenger
- Institute for Cell Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - David Teis
- Institute for Cell Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Daniel J Klionsky
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI.,Life Sciences Institute, University of Michigan, Ann Arbor, MI
| | - Ming Li
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
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19
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Lord CL, Wente SR. Nuclear envelope-vacuole contacts mitigate nuclear pore complex assembly stress. J Cell Biol 2020; 219:211463. [PMID: 33053148 PMCID: PMC7563749 DOI: 10.1083/jcb.202001165] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 08/10/2020] [Accepted: 09/23/2020] [Indexed: 01/04/2023] Open
Abstract
The intricacy of nuclear pore complex (NPC) biogenesis imposes risks of failure that can cause defects in nuclear transport and nuclear envelope (NE) morphology; however, cellular mechanisms used to alleviate NPC assembly stress are not well defined. In the budding yeast Saccharomyces cerevisiae, we demonstrate that NVJ1- and MDM1-enriched NE-vacuole contacts increase when NPC assembly is compromised in several nup mutants, including nup116ΔGLFG cells. These interorganelle nucleus-vacuole junctions (NVJs) cooperate with lipid droplets to maintain viability and enhance NPC formation in assembly mutants. Additionally, NVJs function with ATG1 to remodel the NE and promote vacuole-dependent degradation of specific nucleoporins in nup116ΔGLFG cells. Importantly, NVJs significantly improve the physiology of NPC assembly mutants, despite having only negligible effects when NPC biogenesis is unperturbed. These results therefore define how NE-vacuole interorganelle contacts coordinate responses to mitigate deleterious cellular effects caused by disrupted NPC assembly.
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20
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Rangarajan N, Kapoor I, Li S, Drossopoulos P, White KK, Madden VJ, Dohlman HG. Potassium starvation induces autophagy in yeast. J Biol Chem 2020; 295:14189-14202. [PMID: 32788210 DOI: 10.1074/jbc.ra120.014687] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/02/2020] [Indexed: 01/04/2023] Open
Abstract
Autophagy is a conserved process that recycles cellular contents to promote survival. Although nitrogen limitation is the canonical inducer of autophagy, recent studies have revealed several other nutrients important to this process. In this study, we used a quantitative, high-throughput assay to identify potassium starvation as a new and potent inducer of autophagy in the yeast Saccharomyces cerevisiae We found that potassium-dependent autophagy requires the core pathway kinases Atg1, Atg5, and Vps34, and other components of the phosphatidylinositol 3-kinase complex. Transmission EM revealed abundant autophagosome formation in response to both stimuli. RNA-Seq indicated distinct transcriptional responses: nitrogen affects transport of ions such as copper, whereas potassium targets the organization of other cellular components. Thus, nitrogen and potassium share the ability to influence molecular supply and demand but do so in different ways. Both inputs promote catabolism through bulk autophagy, but result in distinct mechanisms of cellular remodeling and synthesis.
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Affiliation(s)
- Nambirajan Rangarajan
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ishani Kapoor
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Shuang Li
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Peter Drossopoulos
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Kristen K White
- Microscopy Services Laboratory, Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Victoria J Madden
- Microscopy Services Laboratory, Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Henrik G Dohlman
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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21
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Abstract
AbstractEntamoeba histolytica infection causes amoebiasis, which is a global public health problem. The major route of infection is oral ingestion of E. histolytica cysts, cysts being the sole form responsible for host-to-host transmission. Cysts are produced by cell differentiation from proliferative trophozoites in a process termed ‘encystation’. Therefore, encystation is an important process from a medical as well as a biological perspective. Previous electron microscopy studies have shown the ultrastructure of precysts and mature cysts; however, the dynamics of ultrastructural changes during encystation were ambiguous. Here, we analysed a series of Entamoeba invadens encysting cells by transmission electron microscopy. Entamoeba invadens is a model for encystation and the cells were prepared by short interval time course sampling from in vitro encystation-inducing cultures. We related sampled cells to stage conversion, which was monitored in the overall population by flow cytometry. The present approach revealed the dynamics of ultrastructure changes during E. invadens encystation. Importantly, the results indicate a functional linkage of processes that are crucial in encystation, such as glycogen accumulation and cyst wall formation. Hence, this study provides a reference for studying sequential molecular events during Entamoeba encystation.
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22
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Li TT, Zhang JD, Tang JQ, Liu ZC, Li YQ, Chen J, Zou LW. Combined Use of Trichoderma atroviride CCTCCSBW0199 and Brassinolide to Control Botrytis cinerea Infection in Tomato. PLANT DISEASE 2020; 104:1298-1304. [PMID: 32196417 DOI: 10.1094/pdis-07-19-1568-re] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Tomato gray mold caused by Botrytis cinerea is one of the main diseases of tomato and significantly impacts the yield and quality of tomato fruit. The overuse of chemical fungicides has resulted in the development of fungicide-resistant strains. Biological control is becoming an alternative method for the control of plant diseases to replace or decrease the application of traditional synthetic chemical fungicides and genus Trichoderma is widely used as a biological agent for controlling tomato gray mold. Brassinolide (BR) is a plant-growth-promoting steroid. To enhance the efficiency and stability of Trichoderma activity against B. cinerea, an optimal combination of Trichoderma atroviride CCTCCSBW0199 and BR that controls B. cinerea infection in tomato was identified. Strain CCTCCSBW0199 was found to have antagonistic activity against B. cinerea both in vitro and in vivo. In addition, a fermented culture of chlamydospores and metabolites, or metabolites only of strain CCTCCSBW0199 also reduced growth of B. cinerea. BR reduced growth of B. cinerea and had no effect on the sporulation and growth of Trichoderma spp. An application of metabolites of a Trichoderma sp. + BR reduced gray mold on tomato leaves by approximately 70.0%. Furthermore, the activities of induced defense response-related enzyme, such as peroxidase, superoxide dismutase, catalase, and phenylalanine ammonia-lyase were increased in tomato plants treated with a Trichoderma sp. + BR. Our data suggested that applying a mix of metabolites of T. atroviride CCTCCSBW0199 + BR was effective at reducing gray mold of tomato and may lay a theoretical foundation for the development of novel biofungicides.
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Affiliation(s)
- Ting-Ting Li
- School of Agriculture and Biology, Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolism/Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, Shanghai 200240, P.R. China
| | - Jing-di Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolism/Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, Shanghai 200240, P.R. China
| | - Jia-Quan Tang
- School of Agriculture and Biology, Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolism/Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, Shanghai 200240, P.R. China
| | - Zhi-Cheng Liu
- School of Agriculture and Biology, Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolism/Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, Shanghai 200240, P.R. China
| | - Ya-Qian Li
- School of Agriculture and Biology, Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolism/Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, Shanghai 200240, P.R. China
| | - Jie Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolism/Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, Shanghai 200240, P.R. China
| | - Li-Wen Zou
- Dalian Wafangdian Agricultural Technology Extension Service Center, Dalian 116300, P.R. China
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23
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Changes in the Ultrastructure of Candida albicans Treated with Cationic Peptides. Microorganisms 2020; 8:microorganisms8040582. [PMID: 32316565 PMCID: PMC7232200 DOI: 10.3390/microorganisms8040582] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/07/2020] [Accepted: 04/15/2020] [Indexed: 01/12/2023] Open
Abstract
Candida albicans is becoming increasingly harmful for humans, which determines the need for new effective antifungal preparations. Currently, when testing antifungals, various morphological methods are used, among which transmission electron microscopy (TEM) is not the leading one. In this work, we used TEM to study the submicroscopic changes in C. albicans cells induced by cationic peptides R9F2 and (KFF)3K. Studies were performed on C. albicans-34 strain from the Collection of EMTC of ICBFM SB RAS in logarithmic phase. R9F2 and (KFF)3K showed an antifungal effect (MIC 10 and 20 μM) and suppressed fungal hyphal growth. Semithin and ultrathin sections of fungal suspensions incubated with 10 μM of peptides were studied at regular intervals from 15 min to 24 h. The first target of both peptides was plasmalemma, and its “alignment” was the only common morphological manifestation of their effect. Other changes in the plasmalemma and alteration of the vacuole and cell wall ultrastructure distinctly differed in cells treated with R9F2 and (KFF)3K peptides. In general, our work has shown pronounced differences of the temporal and morphologic characteristics of the effect of peptides, evidently related to their physicochemical properties. The benefit of TEM studies of ultrathin sections for understanding the mechanisms of action of antifungal drugs is shown.
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24
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Mazheika I, Voronko O, Kudryavtseva O, Novoselova D, Pozdnyakov L, Mukhin V, Kolomiets O, Kamzolkina O. Nitrogen-obtaining and -conserving strategies in xylotrophic basidiomycetes. Mycologia 2020; 112:455-473. [PMID: 32238121 DOI: 10.1080/00275514.2020.1716567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Nitrogen in sufficient quantities is strictly necessary for all living organisms. In this study, the ability of some xylotrophic basidiomycetes to grow extremely long on a solid growth medium full of carbon nutrition but lacking a nitrogen source in its composition was discovered. The nitrogen oligotrophy of wood-decaying fungi is associated with their adaptation to live in a wood substrate, which is also deficient in nitrogen content. This nitrogen-depleted cultural growth is called "pseudo-foraging" and can be used as a simplified model of wood-decaying growth. Four main nitrogen-obtaining and -conserving strategies (nitrogen concentration, using alternative sources of nitrogen, economy of growth, and nutritional recycling), which are attributed to wood-colonizing xylotrophs in the literature, were revised studying the pseudo-foraging model. Based on the results, some aspects of the behavior of xylotrophs deep in undecomposed wood were predicted. For example, one of the results is that for pseudo-foraging xylotrophs, the main way to obtain nitrogen is its concentration in their mycelium from the nutrient medium in which nitrogen is contained in the impurities of the components of the medium. The result suggests that in bulk solid wood, the nitrogen concentration strategy also dominates the strategy of using diazotrophic and other alternative nitrogen. In addition, three individual unprecedented mechanisms, which supposedly help the xylotrophic fungi to colonize wood in nature (generation of fine mycelium, macrovesicular endocytosis, formation and conversion of super-elongated mitochondria), were investigated in the laboratory.
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Affiliation(s)
- Igor Mazheika
- Lomonosov Moscow State University , Moscow, Russia, 119991.,Vavilov Institute of General Genetics, Russian Academy of Sciences , Moscow, Russia, 117971
| | - Oxana Voronko
- Lomonosov Moscow State University , Moscow, Russia, 119991
| | | | | | - Lev Pozdnyakov
- Lomonosov Moscow State University , Moscow, Russia, 119991
| | - Viktor Mukhin
- Institute of Plant and Animal Ecology, Ural Branch Russian Academy of Sciences , Yekaterinburg, Russia, 620144
| | - Oxana Kolomiets
- Vavilov Institute of General Genetics, Russian Academy of Sciences , Moscow, Russia, 117971
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25
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Huddleston ME, Xiao N, Both AP, Gordon DM. Single amino acid mutations in the Saccharomyces cerevisiae rhomboid peptidase, Pcp1p, alter mitochondrial morphology. Cell Biol Int 2020; 44:200-215. [PMID: 31441130 PMCID: PMC6972574 DOI: 10.1002/cbin.11219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 08/18/2019] [Indexed: 01/24/2023]
Abstract
Key to mitochondrial activities is the maintenance of mitochondrial morphology, specifically cristae structures formed by the invagination of the inner membrane that are enriched in proteins of the electron transport chain. In Saccharomyces cerevisiae , these cristae folds are a result of the membrane fusion activities of Mgm1p and the membrane-bending properties of adenosine triphosphate (ATP) synthase oligomerization. An additional protein linked to mitochondrial morphology is Pcp1p, a serine protease responsible for the proteolytic processing of Mgm1p. Here, we have used hydroxylamine-based random mutagenesis to identify amino acids important for Pcp1p peptidase activity. Using this approach we have isolated five single amino acid mutants that exhibit respiratory growth defects that correlate with loss of mitochondrial genome stability. Reduced Pcp1p protease activity was confirmed by immunoblotting with the accumulation of improperly processed Mgm1p. Ultra-structural analysis of mitochondrial morphology in these mutants found a varying degree of defects in cristae organization. However, not all of the mutants presented with decreased ATP synthase complex assembly as determined by blue native polyacrylamide gel electrophoresis. Together, these data suggest that there is a threshold level of processed Mgm1p required to maintain ATP synthase super-complex assembly and mitochondrial cristae organization.
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Affiliation(s)
| | - Ningyu Xiao
- Department of Biological SciencesMississippi State UniversityMississippi StateMississippi39762USA
| | - Andries Pieter Both
- Department of Biological SciencesMississippi State UniversityMississippi StateMississippi39762USA
| | - Donna M. Gordon
- Department of Biological SciencesMississippi State UniversityMississippi StateMississippi39762USA
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26
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Appadurai D, Gay L, Moharir A, Lang MJ, Duncan MC, Schmidt O, Teis D, Vu TN, Silva M, Jorgensen EM, Babst M. Plasma membrane tension regulates eisosome structure and function. Mol Biol Cell 2019; 31:287-303. [PMID: 31851579 PMCID: PMC7183764 DOI: 10.1091/mbc.e19-04-0218] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Eisosomes are membrane furrows at the cell surface of yeast that have been shown to function in two seemingly distinct pathways, membrane stress response and regulation of nutrient transporters. We found that many stress conditions affect both of these pathways by changing plasma membrane tension and thus the morphology and composition of eisosomes. For example, alkaline stress causes swelling of the cell and an endocytic response, which together increase membrane tension, thereby flattening the eisosomes. The flattened eisosomes affect membrane stress pathways and release nutrient transporters, which aids in their down-regulation. In contrast, glucose starvation or hyperosmotic shock causes cell shrinking, which results in membrane slack and the deepening of eisosomes. Deepened eisosomes are able to trap nutrient transporters and protect them from rapid endocytosis. Therefore, eisosomes seem to coordinate the regulation of both membrane tension and nutrient transporter stability.
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Affiliation(s)
- Daniel Appadurai
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112
| | - Lincoln Gay
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112
| | - Akshay Moharir
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112
| | - Michael J Lang
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
| | - Mara C Duncan
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
| | - Oliver Schmidt
- Division of Cell Biology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - David Teis
- Division of Cell Biology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Thien N Vu
- School of Biological Sciences, Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT 84112
| | - Malan Silva
- School of Biological Sciences, Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT 84112
| | - Erik M Jorgensen
- School of Biological Sciences, Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT 84112
| | - Markus Babst
- Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112
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27
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Membrane Fluidity of Saccharomyces cerevisiae from Huangjiu (Chinese Rice Wine) Is Variably Regulated by OLE1 To Offset the Disruptive Effect of Ethanol. Appl Environ Microbiol 2019; 85:AEM.01620-19. [PMID: 31540996 DOI: 10.1128/aem.01620-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 09/19/2019] [Indexed: 11/20/2022] Open
Abstract
An evolution and resequencing strategy was used to research the genetic basis of Saccharomyces cerevisiae BR20 (with 18 vol% ethanol tolerance) and the evolved strain F23 (with 25 vol% ethanol tolerance). Whole-genome sequencing and RNA sequencing (RNA-seq) indicated that the enhanced ethanol tolerance under 10 vol% ethanol could be attributed to amino acid metabolism, whereas 18 vol% ethanol tolerance was due to fatty acid metabolism. Ultrastructural analysis indicated that F23 exhibited better membrane integrity than did BR20 under ethanol stress. At low concentrations (<5 vol%), the partition of ethanol into the membrane increased the membrane fluidity, which had little effect on cell growth. However, the toxic effects of medium and high ethanol concentrations (5 to 20 vol%) tended to decrease the membrane fluidity. Under high ethanol stress (>10 vol%), the highly tolerant strain was able to maintain a relatively constant fluidity by increasing the content of unsaturated fatty acid (UFA), whereas less-tolerant strains show a continuous decrease in fluidity and UFA content. OLE1, which was identified as the only gene with a differential single-nucleotide polymorphism (SNP) mutation site related to fatty acid metabolism, was significantly changed in response to ethanol. The role of OLE1 in membrane fluidity was positively validated in its overexpressed transformants. Therefore, OLE1 lowered the rate of decline in membrane fluidity and thus enabled the yeast to better fight the deleterious effects of ethanol.IMPORTANCE Yeasts with superior ethanol tolerance are desirable for winemakers and wine industries. In our previous work, strain F23 was evolved with superior ethanol tolerance and fermentation activity to improve the flavor profiles of Chinese rice wine. Therefore, exploring the genomic variations and ethanol tolerance mechanism of strain F23 could contribute to an understanding of its effect on the flavor characteristics in the resulting Chinese rice wine. The cellular membrane plays a vital role in the ethanol tolerance of yeasts; however, how the membrane is regulated to fight the toxic effect of ethanol remains to be elucidated. This study suggests that the membrane fluidity is variably regulated by OLE1 to offset the disruptive effect of ethanol. Current work will help develop more ethanol-tolerant yeast strains for wine industries and contribute to a deep understanding of its high flavor-producing ability.
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28
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Lu H, Shu Q, Lou H, Chen Q. Mitochondria-Mediated Programmed Cell Death in Saccharomyces cerevisiae Induced by Betulinic Acid Is Accelerated by the Deletion of PEP4 Gene. Microorganisms 2019; 7:microorganisms7110538. [PMID: 31703462 PMCID: PMC6920885 DOI: 10.3390/microorganisms7110538] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 10/27/2019] [Accepted: 11/05/2019] [Indexed: 11/22/2022] Open
Abstract
In this work, using Saccharomyces cerevisiae as a model, we showed that BetA could inhibit cell proliferation and lead to lethal cytotoxicity accompanying programmed cell death (PCD). Interestingly, it was found that vacuolar protease Pep4p played a pivotal role in BetA-induced S. cerevisiae PCD. The presence of Pep4p reduced the damage of BetA-induced cells. This work implied that BetA may induce cell death of S. cerevisiae through mitochondria-mediated PCD, and the deletion of Pep4 gene possibly accelerated the effect of PCD. The present investigation provided the preliminary research for the complicated mechanism of BetA-induced cell PCD regulated by vacular protease Pep4p and lay the foundation for understanding of the Pep4p protein in an animal model.
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Affiliation(s)
| | | | | | - Qihe Chen
- Correspondence: ; Tel.: +86-0571-8698-4316
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29
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Hariri H, Speer N, Bowerman J, Rogers S, Fu G, Reetz E, Datta S, Feathers JR, Ugrankar R, Nicastro D, Henne WM. Mdm1 maintains endoplasmic reticulum homeostasis by spatially regulating lipid droplet biogenesis. J Cell Biol 2019; 218:1319-1334. [PMID: 30808705 PMCID: PMC6446837 DOI: 10.1083/jcb.201808119] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 01/10/2019] [Accepted: 01/22/2019] [Indexed: 12/13/2022] Open
Abstract
Excess fatty acids are toxic to cells but can be sequestered as triacylglycerides in lipid droplets. Hariri et al. show that the tethering protein Mdm1 spatially regulates this process at the junction between the endoplasmic reticulum and the yeast vacuole. These findings suggest that Mdm1 can drive spatially defined lipid droplet production to maintain cell homeostasis and protect against lipotoxicity. Lipid droplets (LDs) serve as cytoplasmic reservoirs for energy-rich fatty acids (FAs) stored in the form of triacylglycerides (TAGs). During nutrient stress, yeast LDs cluster adjacent to the vacuole/lysosome, but how this LD accumulation is coordinated remains poorly understood. The ER protein Mdm1 is a molecular tether that plays a role in clustering LDs during nutrient depletion, but its mechanism of function remains unknown. Here, we show that Mdm1 associates with LDs through its hydrophobic N-terminal region, which is sufficient to demarcate sites for LD budding. Mdm1 binds FAs via its Phox-associated domain and coenriches with fatty acyl–coenzyme A ligase Faa1 at LD bud sites. Consistent with this, loss of MDM1 perturbs free FA activation and Dga1-dependent synthesis of TAGs, elevating the cellular FA level, which perturbs ER morphology and sensitizes yeast to FA-induced lipotoxicity. We propose that Mdm1 coordinates FA activation adjacent to the vacuole to promote LD production in response to stress, thus maintaining ER homeostasis.
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Affiliation(s)
- Hanaa Hariri
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Natalie Speer
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Jade Bowerman
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Sean Rogers
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Gang Fu
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Evan Reetz
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Sanchari Datta
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - J Ryan Feathers
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Rupali Ugrankar
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Daniela Nicastro
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
| | - W Mike Henne
- Department of Cell Biology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX
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30
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Yang X, Dong Y, Liu G, Zhang C, Cao Y, Wang C. Effects of nonionic surfactants on pigment excretion and cell morphology in extractive fermentation of Monascus sp. NJ1. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:1233-1239. [PMID: 30066423 DOI: 10.1002/jsfa.9295] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 07/26/2018] [Accepted: 07/29/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Different nonionic surfactants in submerged fermentation of Monascus sp. demonstrate significant differences regarding increasing pigment yield. In this study, 15 surfactants from five series were analyzed to investigate the influence of nonionic surfactants on Monascus pigments, with the aim of simultaneously obtaining a novel nonionic surfactant. RESULTS Addition of the novel surfactant Brij 35 greatly enhanced pigment excretion and demonstrated good biocompatibility. Extracellular red, orange and yellow pigments increased by 1.47-, 1.71- and 2.07-fold respectively. Production of extracellular pigments was not only related to the hydrophile-lipophile balance value (HLB) but also affected by the cloud point temperature (CP) of the fermentation medium. It was found that nonionic surfactants can improve cell membrane permeability and cell storage capacity by modifying the cell walls of Monascus mycelium and by increasing lipid droplet levels, enhancing pigment excretion. Different nonionic surfactants modify Monascus mycelium to different degrees. CONCLUSION The novel surfactant Brij 35, which has good capacity for pigment extraction and biocompatibility, was identified in the analysis. The effects of nonionic surfactants on the secretion of pigments are related to not only the modification of the cell wall and internal structure but also the CP and HLB. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Xuelian Yang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing, China
- School of Food and Chemical Engineering, Beijing Technology & Business University, Beijing, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing, China
| | - Ye Dong
- School of Food and Chemical Engineering, Beijing Technology & Business University, Beijing, China
| | - Guorong Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing, China
- School of Food and Chemical Engineering, Beijing Technology & Business University, Beijing, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing, China
| | - Chan Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing, China
- School of Food and Chemical Engineering, Beijing Technology & Business University, Beijing, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing, China
| | - YanPing Cao
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing, China
- School of Food and Chemical Engineering, Beijing Technology & Business University, Beijing, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing, China
| | - Chengtao Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing, China
- School of Food and Chemical Engineering, Beijing Technology & Business University, Beijing, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing, China
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31
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Abstract
The investigation of autophagy particularly when observed during programmed cell death (PCD) is strongly based on the morphological features recorded with transmission electron microscope (TEM). Here we describe methods to induce and to inhibit autophagy in plants. Also some tips for obtaining better preservation of biological membranes, crucial for the investigation of autophagy, are provided together with information about plant autophagic mutants, use of antibodies and methods for 3D reconstruction of large membrane-bound objects that are commonly formed during autophagic processes leading to PCD in plants.
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32
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Weiner A, Orange F, Lacas‐Gervais S, Rechav K, Ghugtyal V, Bassilana M, Arkowitz RA. On‐site secretory vesicle delivery drives filamentous growth in the fungal pathogenCandida albicans. Cell Microbiol 2018; 21:e12963. [DOI: 10.1111/cmi.12963] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 10/02/2018] [Accepted: 10/04/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Allon Weiner
- Université Côte d'AzurCNRS, Inserm, Institute of Biology Valrose Parc Valrose Nice France
| | | | | | - Katya Rechav
- Chemical Research SupportWeizmann Institute of Science Rehovot Israel
| | - Vikram Ghugtyal
- Université Côte d'AzurCNRS, Inserm, Institute of Biology Valrose Parc Valrose Nice France
| | - Martine Bassilana
- Université Côte d'AzurCNRS, Inserm, Institute of Biology Valrose Parc Valrose Nice France
| | - Robert A. Arkowitz
- Université Côte d'AzurCNRS, Inserm, Institute of Biology Valrose Parc Valrose Nice France
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33
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Zhu X, Cai J, Zhou F, Wu Z, Li D, Li Y, Xie Z, Zhou Y, Liang Y. Genome-wide screening of budding yeast with honokiol to associate mitochondrial function with lipid metabolism. Traffic 2018; 19:867-878. [PMID: 30120820 DOI: 10.1111/tra.12611] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 08/11/2018] [Accepted: 08/13/2018] [Indexed: 12/24/2022]
Abstract
Honokiol (HNK), an important medicinal component of Magnolia officinalis, is reported to possess pharmacological activities against a variety of diseases. However, the molecular mechanisms of HNK medicinal functions are not fully clear. To systematically study the mechanisms of HNK action, we screened a yeast mutant library based on the conserved nature of its genes among eukaryotes. We identified genes associated with increased resistance or sensitivity to HNK after mutation. After functional classification of these genes, we found that most HNK-resistant strains in the largest functional category were petites with mutations in mitochondrial genes, indicating that mitochondria were related to HNK resistance. Additional analysis showed that resistance of petite mutants to HNK was associated with upregulation of the ATP-binding cassette transporter Pdr5, which pumps out HNK. We also found that several HNK-sensitive mitochondria mutants were not petites, and had larger lipid droplets (LDs). Furthermore, HNK treatment on wild-type yeast cells seemed to disrupt mitochondrial morphology, induced triacylglycerol synthesis, and generated supersized LDs surrounded by mitochondria and endoplasmic reticulum (ER). These changes are also applied to atp7Δ mutant if no carbon resource was available. These results suggested that HNK treatment partly impaired normal mitochondrial function to form larger LDs by altering lipid metabolism.
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Affiliation(s)
- Xiaolong Zhu
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China.,Central Laboratory of Yijishan Hospital, Wannan Medical College, Wuhu, China
| | - Juan Cai
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Fan Zhou
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Zulin Wu
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Dan Li
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Technology, Shanghai Jiao Tong University, Shanghai, China
| | - Youbin Li
- School of Pharmacy, Hainan Medical University, Haikou, China
| | - Zhiping Xie
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Technology, Shanghai Jiao Tong University, Shanghai, China
| | - Yiting Zhou
- Department of Biochemistry and Molecular Biology, Dr. Li Dak Sam & Yap Yio Chin Center for Stem Cell and Regenerative Medicine, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yongheng Liang
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
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34
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Wang J, Li M, Zheng F, Niu C, Liu C, Li Q, Sun J. Cell wall polysaccharides: before and after autolysis of brewer's yeast. World J Microbiol Biotechnol 2018; 34:137. [PMID: 30128783 DOI: 10.1007/s11274-018-2508-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 07/20/2018] [Indexed: 12/11/2022]
Abstract
Brewer's yeast is used in production of beer since millennia, and it is receiving increased attention because of its distinct fermentation ability and other biological properties. During fermentation, autolysis occurs naturally at the end of growth cycle of yeast. Yeast cell wall provides yeast with osmotic integrity and holds the cell shape upon the cell wall stresses. The cell wall of yeast consists of β-glucans, chitin, mannoproteins, and proteins that cross linked with glycans and a glycolipid anchor. The variation in composition and amount of cell wall polysaccharides during autolysis in response to cell wall stress, laying significant impacts on the autolysis ability of yeast, either benefiting or destroying the flavor of final products. On the other hand, polysaccharides from yeast cell wall show outstanding health effects and are recommended to be used in functional foods. This article reviews the influence of cell wall polysaccharides on yeast autolysis, covering cell wall structure changings during autolysis, and functions and possible applications of cell wall components derived from yeast autolysis.
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Affiliation(s)
- Jinjing Wang
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China.,Lab of Brewing Science and Engineering of Jiangnan University, China, Wuxi, 214122, Jiangsu, China
| | - Mengqi Li
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China.,Lab of Brewing Science and Engineering of Jiangnan University, China, Wuxi, 214122, Jiangsu, China
| | - Feiyun Zheng
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China.,Lab of Brewing Science and Engineering of Jiangnan University, China, Wuxi, 214122, Jiangsu, China
| | - Chengtuo Niu
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China.,Lab of Brewing Science and Engineering of Jiangnan University, China, Wuxi, 214122, Jiangsu, China
| | - Chunfeng Liu
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China.,Lab of Brewing Science and Engineering of Jiangnan University, China, Wuxi, 214122, Jiangsu, China
| | - Qi Li
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China. .,Lab of Brewing Science and Engineering of Jiangnan University, China, Wuxi, 214122, Jiangsu, China.
| | - Jinyuan Sun
- Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University (BTBU), Beijing, 100048, China.
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Esher SK, Ost KS, Kohlbrenner MA, Pianalto KM, Telzrow CL, Campuzano A, Nichols CB, Munro C, Wormley FL, Alspaugh JA. Defects in intracellular trafficking of fungal cell wall synthases lead to aberrant host immune recognition. PLoS Pathog 2018; 14:e1007126. [PMID: 29864141 PMCID: PMC6002136 DOI: 10.1371/journal.ppat.1007126] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 06/14/2018] [Accepted: 05/29/2018] [Indexed: 11/19/2022] Open
Abstract
The human fungal pathogen, Cryptococcus neoformans, dramatically alters its cell wall, both in size and composition, upon entering the host. This cell wall remodeling is essential for host immune avoidance by this pathogen. In a genetic screen for mutants with changes in their cell wall, we identified a novel protein, Mar1, that controls cell wall organization and immune evasion. Through phenotypic studies of a loss-of-function strain, we have demonstrated that the mar1Δ mutant has an aberrant cell surface and a defect in polysaccharide capsule attachment, resulting in attenuated virulence. Furthermore, the mar1Δ mutant displays increased staining for exposed cell wall chitin and chitosan when the cells are grown in host-like tissue culture conditions. However, HPLC analysis of whole cell walls and RT-PCR analysis of cell wall synthase genes demonstrated that this increased chitin exposure is likely due to decreased levels of glucans and mannans in the outer cell wall layers. We observed that the Mar1 protein differentially localizes to cellular membranes in a condition dependent manner, and we have further shown that the mar1Δ mutant displays defects in intracellular trafficking, resulting in a mislocalization of the β-glucan synthase catalytic subunit, Fks1. These cell surface changes influence the host-pathogen interaction, resulting in increased macrophage activation to microbial challenge in vitro. We established that several host innate immune signaling proteins are required for the observed macrophage activation, including the Card9 and MyD88 adaptor proteins, as well as the Dectin-1 and TLR2 pattern recognition receptors. These studies explore novel mechanisms by which a microbial pathogen regulates its cell surface in response to the host, as well as how dysregulation of this adaptive response leads to defective immune avoidance.
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Affiliation(s)
- Shannon K. Esher
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
| | - Kyla S. Ost
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
| | - Maria A. Kohlbrenner
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
| | - Kaila M. Pianalto
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
| | - Calla L. Telzrow
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
| | - Althea Campuzano
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Connie B. Nichols
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
| | - Carol Munro
- MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Floyd L. Wormley
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - J. Andrew Alspaugh
- Departments of Molecular Genetics and Microbiology/Medicine, Duke University School of Medicine, Durham, NC, United States of America
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36
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Quon E, Sere YY, Chauhan N, Johansen J, Sullivan DP, Dittman JS, Rice WJ, Chan RB, Di Paolo G, Beh CT, Menon AK. Endoplasmic reticulum-plasma membrane contact sites integrate sterol and phospholipid regulation. PLoS Biol 2018; 16:e2003864. [PMID: 29782498 PMCID: PMC5983861 DOI: 10.1371/journal.pbio.2003864] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 06/01/2018] [Accepted: 04/20/2018] [Indexed: 01/21/2023] Open
Abstract
Tether proteins attach the endoplasmic reticulum (ER) to other cellular membranes, thereby creating contact sites that are proposed to form platforms for regulating lipid homeostasis and facilitating non-vesicular lipid exchange. Sterols are synthesized in the ER and transported by non-vesicular mechanisms to the plasma membrane (PM), where they represent almost half of all PM lipids and contribute critically to the barrier function of the PM. To determine whether contact sites are important for both sterol exchange between the ER and PM and intermembrane regulation of lipid metabolism, we generated Δ-super-tether (Δ-s-tether) yeast cells that lack six previously identified tethering proteins (yeast extended synatotagmin [E-Syt], vesicle-associated membrane protein [VAMP]-associated protein [VAP], and TMEM16-anoctamin homologues) as well as the presumptive tether Ice2. Despite the lack of ER-PM contacts in these cells, ER-PM sterol exchange is robust, indicating that the sterol transport machinery is either absent from or not uniquely located at contact sites. Unexpectedly, we found that the transport of exogenously supplied sterol to the ER occurs more slowly in Δ-s-tether cells than in wild-type (WT) cells. We pinpointed this defect to changes in sterol organization and transbilayer movement within the PM bilayer caused by phospholipid dysregulation, evinced by changes in the abundance and organization of PM lipids. Indeed, deletion of either OSH4, which encodes a sterol/phosphatidylinositol-4-phosphate (PI4P) exchange protein, or SAC1, which encodes a PI4P phosphatase, caused synthetic lethality in Δ-s-tether cells due to disruptions in redundant PI4P and phospholipid regulatory pathways. The growth defect of Δ-s-tether cells was rescued with an artificial "ER-PM staple," a tether assembled from unrelated non-yeast protein domains, indicating that endogenous tether proteins have nonspecific bridging functions. Finally, we discovered that sterols play a role in regulating ER-PM contact site formation. In sterol-depleted cells, levels of the yeast E-Syt tether Tcb3 were induced and ER-PM contact increased dramatically. These results support a model in which ER-PM contact sites provide a nexus for coordinating the complex interrelationship between sterols, sphingolipids, and phospholipids that maintain PM composition and integrity. Almost half of the inner surface area of the yeast plasma membrane (PM) is covered with closely associated cortical endoplasmic reticulum (ER). In yeast and human cells, it has been proposed that ER-anchored tether proteins staple the ER to the PM, creating membrane contact sites at which lipid transport between the ER and PM and membrane lipid synthesis are coordinately regulated, but the potential mechanisms are unclear. Here, we test this idea by creating yeast cells that lack all ER-PM tethers. We find that whereas the bidirectional transport of sterols between the ER and PM is unaffected in these cells, sterols within the PM are disorganized due to disruptions in phospholipid biosynthesis that alter PM lipid composition. In particular, we show that phosphatidylinositol-4-phosphate, a phospholipid needed for intracellular signaling and membrane trafficking, accumulates within the PM. Some of these defects can be rescued by reinstating membrane contacts via expression of an artificial tether. However, correction is also achieved without the creation of contacts by supplementing the growth medium with a precursor of membrane phospholipids. Based on these results, we propose that ER-PM contacts do not play a major role as physical conduits for lipid exchange but rather serve as regulatory interfaces to integrate lipid synthesis pathways.
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Affiliation(s)
- Evan Quon
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Yves Y. Sere
- Department of Biochemistry, Weill Cornell Medical College, New York, New York, United States of America
| | - Neha Chauhan
- Department of Biochemistry, Weill Cornell Medical College, New York, New York, United States of America
| | - Jesper Johansen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - David P. Sullivan
- Department of Biochemistry, Weill Cornell Medical College, New York, New York, United States of America
| | - Jeremy S. Dittman
- Department of Biochemistry, Weill Cornell Medical College, New York, New York, United States of America
| | - William J. Rice
- Simons Electron Microscopy Center at the New York Structural Biology Center, New York, New York, United States of America
| | - Robin B. Chan
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- Denali Therapeutics, South San Francisco, California, United States of America
| | - Christopher T. Beh
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
- Centre for Cell Biology, Development, and Disease, Simon Fraser University, Burnaby, British Columbia, Canada
- * E-mail: (AKM); (CTB)
| | - Anant K. Menon
- Department of Biochemistry, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (AKM); (CTB)
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37
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Cell permeability and nuclear DNA staining by propidium iodide in basidiomycetous yeasts. Appl Microbiol Biotechnol 2018; 102:4183-4191. [DOI: 10.1007/s00253-018-8906-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 02/26/2018] [Accepted: 02/28/2018] [Indexed: 10/17/2022]
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38
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Abstract
The methylotropic yeast Pichia pastoris is a model organism for the study of autophagy and peroxisome biogenesis. Being able to look at the organism via transmission electron microscopy (TEM) can yield valuable data on the morphology of the secretory pathway and many other organelles of interest. However, preparing the yeast for TEM work can be very arduous and costly. One of the reasons P. pastoris is so hard to prepare for visualization is because its cell wall is very thick and tough compared to the membrane of a mammalian cell. Thus, P. pastoris is notoriously difficult to infiltrate with fixatives, a step necessary to maintain its ultrastructure. This article outlines an efficient and cost effective way to prepare P. pastoris for TEM without the need for certain specialized equipment. With this protocol, excellent pictures can be obtained by using the buffers, KMnO4, sorbitol, and PIPES, along with glutaraldehyde. These components preserve the ultrastructure of the yeast without any apparent artifactual change in morphology.
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39
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M NK, V B S C T, B CS, J S B. Saccharomyces cerevisiae lipid droplet associated enzyme Ypr147cp shows both TAG lipase and ester hydrolase activities. J GEN APPL MICROBIOL 2018; 64:76-83. [PMID: 29491250 DOI: 10.2323/jgam.2017.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Saccharomyces cerevisiae Ypr147cp was found localized to lipid droplets but the physiological role of Ypr147cp remains unknown. Sequence analysis of Ypr147cp revealed an α/β hydrolase domain along with the conserved GXSXG lipase motif. Recombinant Ypr147cp showed both triacylglycerol lipase and ester hydrolase activities. Knock out of YPR147C led to accumulation of TAG in ypr147cΔ when compared to wild type (WT). In addition, transmission electron microscopic analysis of ypr147cΔ cells revealed a greater number of lipid bodies, justifying the increase in TAG content, and the phenotype was rescued upon overexpression of YPR147C in ypr147cΔ. Moreover, the lipid profiling confirmed the accumulation of fatty acids derived from neutral and phospholipids in ypr147cΔ cells. Based on these results, Ypr147cp is identified as a lipid droplet associated triacylglycerol lipase along with an ester hydrolyzing capacity.
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40
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Piva RH, Rocha MC, Piva DH, Montedo ORK, Imasato H, Malavazi I, Rodrigues-Filho UP. Combating pathogens with Cs 2.5H 0.5PW 12O 40 nanoparticles: a new proton-regulated antimicrobial agent. J Mater Chem B 2018; 6:143-152. [PMID: 32254202 DOI: 10.1039/c7tb02763j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The transfer of pathogens from contaminated surfaces to patients is one of the main causes of health care-associated infections (HCAIs). Cases of HCAIs due to multidrug-resistant organisms have been growing worldwide, whereas inorganic nano-antimicrobials are valuable today for the prevention and control of HCAIs. Here, we present a cesium salt of phosphotungstic heteropolyacid (Cs2.5H0.5PW12O40) as a promising nanomaterial for use in antimicrobial product technologies. This water-insoluble Keggin salt exhibits a broad biocide spectrum against Gram-positive and Gram-negative bacteria, yeasts, and filamentous fungi even under dark conditions. The Cs2.5H0.5PW12O40 nanoparticles (NPs) act as a proton-regulated antimicrobial whose activity is mediated on the release of hydronium ions (H3O+), yielding an in situ acidic pH several units below those tolerable by most of the fungal and bacterial nosocomial pathogens.
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Affiliation(s)
- Roger Honorato Piva
- Grupo de Química de Materiais Híbridos e Inorgânicos, Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos - SP, Brazil.
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41
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Hariri H, Rogers S, Ugrankar R, Liu YL, Feathers JR, Henne WM. Lipid droplet biogenesis is spatially coordinated at ER-vacuole contacts under nutritional stress. EMBO Rep 2017; 19:57-72. [PMID: 29146766 DOI: 10.15252/embr.201744815] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 10/12/2017] [Accepted: 10/23/2017] [Indexed: 12/20/2022] Open
Abstract
Eukaryotic cells store lipids in cytosolic organelles known as lipid droplets (LDs). Lipid droplet bud from the endoplasmic reticulum (ER), and may be harvested by the vacuole for energy during prolonged periods of starvation. How cells spatially coordinate LD production is poorly understood. Here, we demonstrate that yeast ER-vacuole contact sites (NVJs) physically expand in response to metabolic stress, and serve as sites for LD production. NVJ tether Mdm1 demarcates sites of LD budding, and interacts with fatty acyl-CoA synthases at the NVJ periphery. Artificially expanding the NVJ through over-expressing Mdm1 is sufficient to drive NVJ-associated LD production, whereas ablating the NVJ induces defects in fatty acid-to-triglyceride production. Collectively, our data suggest a tight metabolic link between nutritional stress and LD biogenesis that is spatially coordinated at ER-vacuole contact sites.
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Affiliation(s)
- Hanaa Hariri
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Sean Rogers
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Rupali Ugrankar
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yang Lydia Liu
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - J Ryan Feathers
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - W Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
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42
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Polonelli L, Ciociola T, Sperindè M, Giovati L, D'Adda T, Galati S, Travassos LR, Magliani W, Conti S. Fungicidal activity of peptides encoded by immunoglobulin genes. Sci Rep 2017; 7:10896. [PMID: 28883642 PMCID: PMC5589769 DOI: 10.1038/s41598-017-11396-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/23/2017] [Indexed: 11/30/2022] Open
Abstract
Evidence from previous works disclosed the antimicrobial, antiviral, anti-tumour and/or immunomodulatory activity exerted, through different mechanisms of action, by peptides expressed in the complementarity-determining regions or even in the constant region of antibodies, independently from their specificity and isotype. Presently, we report the selection, from available databases, of peptide sequences encoded by immunoglobulin genes for the evaluation of their potential biological activities. Synthetic peptides representing the translated products of J lambda and J heavy genes proved to act in vitro against pathogenic fungi, entering yeast cells and causing their death, and exerted a therapeutic effect in a Galleria mellonella model of infection by Candida albicans. No haemolytic, cytotoxic and genotoxic effects were observed on mammalian cells. These findings raise the hypothesis that antibodies could be the evolutionary result of the adaptive combination of gene products ancestrally devoted to innate antimicrobial immunity.
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Affiliation(s)
- Luciano Polonelli
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Tecla Ciociola
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Martina Sperindè
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Laura Giovati
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Tiziana D'Adda
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Serena Galati
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Luiz R Travassos
- Experimental Oncology Unit, Federal University of São Paulo (UNIFESP), São Paulo, Brazil
| | - Walter Magliani
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Stefania Conti
- Department of Medicine and Surgery, University of Parma, Parma, Italy.
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43
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Oku M, Maeda Y, Kagohashi Y, Kondo T, Yamada M, Fujimoto T, Sakai Y. Evidence for ESCRT- and clathrin-dependent microautophagy. J Cell Biol 2017; 216:3263-3274. [PMID: 28838958 PMCID: PMC5626533 DOI: 10.1083/jcb.201611029] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 04/27/2017] [Accepted: 07/24/2017] [Indexed: 12/20/2022] Open
Abstract
Microautophagy is a mode of autophagy in which the lysosomal or vacuolar membrane invaginates and engulfs target components. Oku et al. show that, upon a diauxic shift, yeast microautophagy involves recruitment of ESCRT proteins to the vacuolar membrane, including clathrin-interacting Vps27, and uptake of lipid droplets by the vacuole. Microautophagy refers to a mode of autophagy in which the lysosomal or vacuolar membrane invaginates and directly engulfs target components. The molecular machinery of membrane dynamics driving microautophagy is still elusive. Using immunochemical monitoring of yeast vacuolar transmembrane proteins, Vph1 and Pho8, fused to fluorescent proteins, we obtained evidence showing an induction of microautophagy after a diauxic shift in the yeast Saccharomyces cerevisiae. Components of the endosomal sorting complex required for transport machinery were found to be required for this process, and the gateway protein of the machinery, Vps27, was observed to change its localization onto the vacuolar membrane after a diauxic shift. We revealed the functional importance of Vps27’s interaction with clathrin in this microautophagy that also contributed to uptake of lipid droplets into the vacuole. This study sheds light on the molecular mechanism of microautophagy, which does not require the core Atg proteins.
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Affiliation(s)
- Masahide Oku
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Yuichiro Maeda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Yoko Kagohashi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takeshi Kondo
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Mai Yamada
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Toyoshi Fujimoto
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yasuyoshi Sakai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan .,Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan
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44
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Mehlomakulu NN, Prior KJ, Setati ME, Divol B. Candida pyralidae killer toxin disrupts the cell wall of Brettanomyces bruxellensis in red grape juice. J Appl Microbiol 2017; 122:747-758. [PMID: 27992098 DOI: 10.1111/jam.13383] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 12/14/2016] [Accepted: 12/14/2016] [Indexed: 11/27/2022]
Abstract
AIMS The control of the wine spoilage yeast Brettanomyces bruxellensis using biological methods such as killer toxins (instead of the traditional chemical methods, e.g. SO2 ) has been the focus of several studies within the last decade. Our previous research demonstrated that the killer toxins CpKT1 and CpKT2 isolated from the wine yeast Candida pyralidae were active and stable under winemaking conditions. In this study, we report the possible mode of action of CpKT1 on B. bruxellensis cells in red grape juice. METHODS AND RESULTS Brettanomyces bruxellensis cells were exposed to CpKT1 either directly or through co-inoculation with C. pyralidae. This exposure yielded a temporary or permanent decline of the spoilage yeast population depending on the initial cell concentration. Scanning electron microscopy revealed cell surface abrasion while propidium iodide viability staining showed that CpKT1 caused plasma membrane damage on B. bruxellensis cells. Our data show that the exposure to CpKT1 resulted in increased levels of β-glucan, suggesting a compensatory response of the sensitive cells. CONCLUSIONS The toxin CpKT1 causes cell membrane and cell wall damage in B. bruxellensis. SIGNIFICANCE AND IMPACT OF THE STUDY Candida pyralidae shows potential to be used as a biocontrol agent against B. bruxellensis in grape juice/wine.
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Affiliation(s)
- N N Mehlomakulu
- Institute for Wine Biotechnology, Department of Oenology and Viticulture, Stellenbosch University, Matieland, South Africa
| | - K J Prior
- Institute for Wine Biotechnology, Department of Oenology and Viticulture, Stellenbosch University, Matieland, South Africa
| | - M E Setati
- Institute for Wine Biotechnology, Department of Oenology and Viticulture, Stellenbosch University, Matieland, South Africa
| | - B Divol
- Institute for Wine Biotechnology, Department of Oenology and Viticulture, Stellenbosch University, Matieland, South Africa
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45
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Fazal Z, Pelowitz J, Johnson PE, Harper JC, Brinker CJ, Jakobsson E. Three-Dimensional Encapsulation of Saccharomyces cerevisiae in Silicate Matrices Creates Distinct Metabolic States as Revealed by Gene Chip Analysis. ACS NANO 2017; 11:3560-3575. [PMID: 28287261 DOI: 10.1021/acsnano.6b06385] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In order to design hybrid cellular/synthetic devices such as sensors and vaccines, it is important to understand how the metabolic state of living cells changes upon physical confinement within three-dimensional (3D) matrices. We analyze the gene expression patterns of stationary phase Saccharomyces cerevisiae (S. cerevisiae) cells encapsulated within three distinct nanostructured silica matrices and relate those patterns to known naturally occurring metabolic states. Silica encapsulation methods employed were lipid-templated mesophase silica thin films formed by cell-directed assembly (CDA), lipid-templated mesophase silica particles formed by spray drying (SD), and glycerol-doped silica gel monoliths prepared from an aqueous silicate (AqS+g) precursor solution. It was found that the cells for all three-encapsulated methods enter quiescent states characteristic of response to stress, albeit to different degrees and with differences in detail. By the measure of enrichment of stress-related gene ontology categories, we find that the AqS+g encapsulation is more amenable to the cells than CDA and SD encapsulation. We hypothesize that this differential response in the AqS+g encapsulation is related to four properties of the encapsulating gel: (1) oxygen permeability, (2) relative softness of the material, (3) development of a protective sheath around individual cells (visible in TEM micrographs vide infra), and (4) the presence of glycerol in the gel, which has been previously noted to serve as a protectant for encapsulated cells and can serve as the sole carbon source for S. cerevisiae under aerobic conditions. This work represents a combination of experiment and analysis aimed at the design and development of 3D encapsulation procedures to induce, and perhaps control, well-defined physiological behaviors.
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Affiliation(s)
- Zeeshan Fazal
- Department of Biosciences, COMSATS Institute of Information Technology , Park Road, Tarlai Kalan, Islamabad 45550, Pakistan
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46
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Zienkiewicz K, Zienkiewicz A, Poliner E, Du ZY, Vollheyde K, Herrfurth C, Marmon S, Farré EM, Feussner I, Benning C. Nannochloropsis, a rich source of diacylglycerol acyltransferases for engineering of triacylglycerol content in different hosts. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:8. [PMID: 28070221 PMCID: PMC5210179 DOI: 10.1186/s13068-016-0686-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 12/10/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Photosynthetic microalgae are considered a viable and sustainable resource for biofuel feedstocks, because they can produce higher biomass per land area than plants and can be grown on non-arable land. Among many microalgae considered for biofuel production, Nannochloropsis oceanica (CCMP1779) is particularly promising, because following nutrient deprivation it produces very high amounts of triacylglycerols (TAG). The committed step in TAG synthesis is catalyzed by acyl-CoA:diacylglycerol acyltransferase (DGAT). Remarkably, a total of 13 putative DGAT-encoding genes have been previously identified in CCMP1779 but most have not yet been studied in detail. RESULTS Based on their expression profile, six out of 12 type-2 DGAT-encoding genes (NoDGTT1-NoDGTT6) were chosen for their possible role in TAG biosynthesis and the respective cDNAs were expressed in a TAG synthesis-deficient mutant of yeast. Yeast expressing NoDGTT5 accumulated TAG to the highest level. Over-expression of NoDGTT5 in CCMP1779 grown in N-replete medium resulted in levels of TAG normally observed only after N deprivation. Reduced growth rates accompanied NoDGTT5 over-expression in CCMP1779. Constitutive expression of NoDGTT5 in Arabidopsis thaliana was accompanied by increased TAG content in seeds and leaves. A broad substrate specificity for NoDGTT5 was revealed, with preference for unsaturated acyl groups. Furthermore, NoDGTT5 was able to successfully rescue the Arabidopsis tag1-1 mutant by restoring the TAG content in seeds. CONCLUSIONS Taken together, our results identified NoDGTT5 as the most promising gene for the engineering of TAG synthesis in multiple hosts among the 13 DGAT-encoding genes of N. oceanica CCMP1779. Consequently, this study demonstrates the potential of NoDGTT5 as a tool for enhancing the energy density in biomass by increasing TAG content in transgenic crops used for biofuel production.
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Affiliation(s)
- Krzysztof Zienkiewicz
- Michigan State University-US Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
| | - Agnieszka Zienkiewicz
- Michigan State University-US Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
- Great Lakes Bioenergy Center, Michigan State University, East Lansing, MI 48824 USA
| | - Eric Poliner
- Cell and Molecular Biology Program, Michigan State University, East Lansing, MI 48824 USA
| | - Zhi-Yan Du
- Michigan State University-US Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
| | - Katharina Vollheyde
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
| | - Cornelia Herrfurth
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
| | - Sofia Marmon
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
- Dept. of Plant Breeding, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Eva M. Farré
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
- Department of Plant Biochemistry, Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University, 37073 Göttingen, Germany
- Department of Plant Biochemistry, International Center for Advanced Studies of Energy Conversion (ICASEC), Georg-August-University, 37073 Göttingen, Germany
| | - Christoph Benning
- Michigan State University-US Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
- Great Lakes Bioenergy Center, Michigan State University, East Lansing, MI 48824 USA
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
- Department Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824 USA
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47
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Cristobal-Sarramian A, Radulovic M, Kohlwein S. Methods to Measure Lipophagy in Yeast. Methods Enzymol 2017; 588:395-412. [DOI: 10.1016/bs.mie.2016.09.087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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48
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Feng Y, Backues SK, Baba M, Heo JM, Harper JW, Klionsky DJ. Phosphorylation of Atg9 regulates movement to the phagophore assembly site and the rate of autophagosome formation. Autophagy 2016; 12:648-58. [PMID: 27050455 DOI: 10.1080/15548627.2016.1157237] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Macroautophagy is primarily a degradative process that cells use to break down their own components to recycle macromolecules and provide energy under stress conditions, and defects in macroautophagy lead to a wide range of diseases. Atg9, conserved from yeast to mammals, is the only identified transmembrane protein in the yeast core macroautophagy machinery required for formation of the sequestering compartment termed the autophagosome. This protein undergoes dynamic movement between the phagophore assembly site (PAS), where the autophagosome precursor is nucleated, and peripheral sites that may provide donor membrane for expansion of the phagophore. Atg9 is a phosphoprotein that is regulated by the Atg1 kinase. We used stable isotope labeling by amino acids in cell culture (SILAC) to identify phosphorylation sites on this protein and identified an Atg1-independent phosphorylation site at serine 122. A nonphosphorylatable Atg9 mutant showed decreased autophagy activity, whereas the phosphomimetic mutant enhanced activity. Electron microscopy analysis suggests that the different levels of autophagy activity reflect differences in autophagosome formation, correlating with the delivery of Atg9 to the PAS. Finally, this phosphorylation regulates Atg9 interaction with Atg23 and Atg27.
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Affiliation(s)
- Yuchen Feng
- a Life Sciences Institute and the Department of Molecular, Cellular and Developmental Biology, University of Michigan , Ann Arbor , MI , USA
| | - Steven K Backues
- a Life Sciences Institute and the Department of Molecular, Cellular and Developmental Biology, University of Michigan , Ann Arbor , MI , USA
| | - Misuzu Baba
- b Research Institute for Science and Technology, Kogakuin University , Tokyo , Japan
| | - Jin-mi Heo
- c Department of Cell Biology , Harvard Medical School , Boston , MA USA
| | - J Wade Harper
- c Department of Cell Biology , Harvard Medical School , Boston , MA USA
| | - Daniel J Klionsky
- a Life Sciences Institute and the Department of Molecular, Cellular and Developmental Biology, University of Michigan , Ann Arbor , MI , USA
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Yamashita SI, Jin X, Furukawa K, Hamasaki M, Nezu A, Otera H, Saigusa T, Yoshimori T, Sakai Y, Mihara K, Kanki T. Mitochondrial division occurs concurrently with autophagosome formation but independently of Drp1 during mitophagy. J Cell Biol 2016; 215:649-665. [PMID: 27903607 PMCID: PMC5147001 DOI: 10.1083/jcb.201605093] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/02/2016] [Accepted: 10/26/2016] [Indexed: 01/14/2023] Open
Abstract
Mitophagy is thought to play an important role in mitochondrial quality control. Mitochondrial division is believed to occur first, and autophagosome formation subsequently occurs to enwrap mitochondria as a process of mitophagy. However, there has not been any temporal analysis of mitochondrial division and autophagosome formation in mitophagy. Therefore, the relationships among these processes remain unclear. We show that the mitochondrial division factor Dnm1 in yeast or Drp1 in mammalian cells is dispensable for mitophagy. Autophagosome formation factors, such as FIP200, ATG14, and WIPIs, were essential for the mitochondrial division for mitophagy. Live-cell imaging showed that isolation membranes formed on the mitochondria. A small portion of the mitochondria then divided from parental mitochondria simultaneously with the extension of isolation membranes and autophagosome formation. These findings suggest the presence of a mitophagy process in which mitochondrial division for mitophagy is accomplished together with autophagosome formation.
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Affiliation(s)
- Shun-Ichi Yamashita
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Xiulian Jin
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Kentaro Furukawa
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Maho Hamasaki
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Akiko Nezu
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Hidenori Otera
- Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Tetsu Saigusa
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Tamotsu Yoshimori
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Yasuyoshi Sakai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Katsuyoshi Mihara
- Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Tomotake Kanki
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
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50
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Bona E, Cantamessa S, Pavan M, Novello G, Massa N, Rocchetti A, Berta G, Gamalero E. Sensitivity of Candida albicans to essential oils: are they an alternative to antifungal agents? J Appl Microbiol 2016; 121:1530-1545. [PMID: 27568869 DOI: 10.1111/jam.13282] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/14/2016] [Accepted: 08/25/2016] [Indexed: 11/30/2022]
Abstract
AIMS Candida albicans is an important opportunistic pathogen, responsible for the majority of yeast infections in humans. Essential oils, extracted from aromatic plants, are well-known antimicrobial agents, characterized by a broad spectrum of activities, including antifungal properties. The aim of this work was to assess the sensitivity of 30 different vaginal isolated strains of C. albicans to 12 essential oils, compared to the three main used drugs (clotrimazole, fluconazole and itraconazole). METHODS AND RESULTS Thirty strains of C. albicans were isolated from vaginal swab on CHROMagar™ Candida. The agar disc diffusion method was employed to determine the sensitivity to the essential oils. The antifungal activity of the essential oils and antifungal drugs (clotrimazole, itraconazole and fluconazole) were investigated using a microdilution method. Transmission and scanning electron microscopy analyses were performed to get a deep inside on cellular damages. Mint, basil, lavender, tea tree oil, winter savory and oregano essential oils inhibited both the growth and the activity of C. albicans more efficiently than clotrimazole. Damages induced by essential oils at the cellular level were stronger than those caused by clotrimazole. CONCLUSIONS Candida albicans is more sensitive to different essential oils compared to the main used drugs. Moreover, the essential oil affected mainly the cell wall and the membranes of the yeast. SIGNIFICANCE AND IMPACT OF THE STUDY The results of this work support the research for new alternatives or complementary therapies against vaginal candidiasis.
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Affiliation(s)
- E Bona
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
| | - S Cantamessa
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
| | - M Pavan
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
| | - G Novello
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
| | - N Massa
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
| | - A Rocchetti
- Azienda Sanitaria Santi Antonio, Biagio e Cesare Arrigo, Alessandria, Italy
| | - G Berta
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
| | - E Gamalero
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Alessandria, Italy
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