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Ostroumova OS, Efimova SS. Lipid-Centric Approaches in Combating Infectious Diseases: Antibacterials, Antifungals and Antivirals with Lipid-Associated Mechanisms of Action. Antibiotics (Basel) 2023; 12:1716. [PMID: 38136750 PMCID: PMC10741038 DOI: 10.3390/antibiotics12121716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/05/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023] Open
Abstract
One of the global challenges of the 21st century is the increase in mortality from infectious diseases against the backdrop of the spread of antibiotic-resistant pathogenic microorganisms. In this regard, it is worth targeting antibacterials towards the membranes of pathogens that are quite conservative and not amenable to elimination. This review is an attempt to critically analyze the possibilities of targeting antimicrobial agents towards enzymes involved in pathogen lipid biosynthesis or towards bacterial, fungal, and viral lipid membranes, to increase the permeability via pore formation and to modulate the membranes' properties in a manner that makes them incompatible with the pathogen's life cycle. This review discusses the advantages and disadvantages of each approach in the search for highly effective but nontoxic antimicrobial agents. Examples of compounds with a proven molecular mechanism of action are presented, and the types of the most promising pharmacophores for further research and the improvement of the characteristics of antibiotics are discussed. The strategies that pathogens use for survival in terms of modulating the lipid composition and physical properties of the membrane, achieving a balance between resistance to antibiotics and the ability to facilitate all necessary transport and signaling processes, are also considered.
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Affiliation(s)
- Olga S. Ostroumova
- Laboratory of Membrane and Ion Channel Modeling, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Ave. 4, St. Petersburg 194064, Russia;
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Sokołowska B, Orłowska M, Okrasińska A, Piłsyk S, Pawłowska J, Muszewska A. What can be lost? Genomic perspective on the lipid metabolism of Mucoromycota. IMA Fungus 2023; 14:22. [PMID: 37932857 PMCID: PMC10629195 DOI: 10.1186/s43008-023-00127-4] [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: 12/02/2022] [Accepted: 10/23/2023] [Indexed: 11/08/2023] Open
Abstract
Mucoromycota is a phylum of early diverging fungal (EDF) lineages, of mostly plant-associated terrestrial fungi. Some strains have been selected as promising biotechnological organisms due to their ability to produce polyunsaturated fatty acids and efficient conversion of nutrients into lipids. Others get their lipids from the host plant and are unable to produce even the essential ones on their own. Following the advancement in EDF genome sequencing, we carried out a systematic survey of lipid metabolism protein families across different EDF lineages. This enabled us to explore the genomic basis of the previously documented ability to produce several types of lipids within the fungal tree of life. The core lipid metabolism genes showed no significant diversity in distribution, however specialized lipid metabolic pathways differed in this regard among different fungal lineages. In total 165 out of 202 genes involved in lipid metabolism were present in all tested fungal lineages, while remaining 37 genes were found to be absent in some of fungal lineages. Duplications were observed for 69 genes. For the first time we demonstrate that ergosterol is not being produced by several independent groups of plant-associated fungi due to the losses of different ERG genes. Instead, they possess an ancestral pathway leading to the synthesis of cholesterol, which is absent in other fungal lineages. The lack of diacylglycerol kinase in both Mortierellomycotina and Blastocladiomycota opens the question on sterol equilibrium regulation in these organisms. Early diverging fungi retained most of beta oxidation components common with animals including Nudt7, Nudt12 and Nudt19 pointing at peroxisome divergence in Dikarya. Finally, Glomeromycotina and Mortierellomycotina representatives have a similar set of desaturases and elongases related to the synthesis of complex, polyunsaturated fatty acids pointing at an ancient expansion of fatty acid metabolism currently being explored by biotechnological studies.
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Affiliation(s)
- Blanka Sokołowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106, Warsaw, Poland
- Faculty of Biology, Biological and Chemical Research Centre, Institute of Evolutionary Biology, University of Warsaw, Zwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Małgorzata Orłowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106, Warsaw, Poland
- Faculty of Biology, Biological and Chemical Research Centre, Institute of Evolutionary Biology, University of Warsaw, Zwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Alicja Okrasińska
- Faculty of Biology, Biological and Chemical Research Centre, Institute of Evolutionary Biology, University of Warsaw, Zwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Sebastian Piłsyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106, Warsaw, Poland
| | - Julia Pawłowska
- Faculty of Biology, Biological and Chemical Research Centre, Institute of Evolutionary Biology, University of Warsaw, Zwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Anna Muszewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106, Warsaw, Poland.
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3
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Martins TS, Costa RS, Vilaça R, Lemos C, Teixeira V, Pereira C, Costa V. Iron Limitation Restores Autophagy and Increases Lifespan in the Yeast Model of Niemann–Pick Type C1. Int J Mol Sci 2023; 24:ijms24076221. [PMID: 37047194 PMCID: PMC10094029 DOI: 10.3390/ijms24076221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
Niemann–Pick type C1 (NPC1) is an endolysosomal transmembrane protein involved in the export of cholesterol and sphingolipids to other cellular compartments such as the endoplasmic reticulum and plasma membrane. NPC1 loss of function is the major cause of NPC disease, a rare lysosomal storage disorder characterized by an abnormal accumulation of lipids in the late endosomal/lysosomal network, mitochondrial dysfunction, and impaired autophagy. NPC phenotypes are conserved in yeast lacking Ncr1, an orthologue of human NPC1, leading to premature aging. Herein, we performed a phosphoproteomic analysis to investigate the effect of Ncr1 loss on cellular functions mediated by the yeast lysosome-like vacuoles. Our results revealed changes in vacuolar membrane proteins that are associated mostly with vesicle biology (fusion, transport, organization), autophagy, and ion homeostasis, including iron, manganese, and calcium. Consistently, the cytoplasm to vacuole targeting (Cvt) pathway was increased in ncr1∆ cells and autophagy was compromised despite TORC1 inhibition. Moreover, ncr1∆ cells exhibited iron overload mediated by the low-iron sensing transcription factor Aft1. Iron deprivation restored the autophagic flux of ncr1∆ cells and increased its chronological lifespan and oxidative stress resistance. These results implicate iron overload on autophagy impairment, oxidative stress sensitivity, and cell death in the yeast model of NPC1.
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Wang H, Zhang Y, Wang J, Chen Y, Hou T, Zhao Y, Ma Z. The sphinganine C4-hydroxylase FgSur2 regulates sensitivity to azole antifungal agents and virulence of Fusarium graminearum. Microbiol Res 2023; 271:127347. [PMID: 36907072 DOI: 10.1016/j.micres.2023.127347] [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: 01/06/2023] [Revised: 02/19/2023] [Accepted: 02/26/2023] [Indexed: 03/09/2023]
Abstract
Lipid rafts consisting of ergosterol and sphingolipids in the lipid membrane of cells play important roles in various cellular processes. However, the functions of sphingolipids and their synthetic genes in phytopathogenic fungi have not been well understood yet. In this study, we conducted genome-wide searches and carried out systematic gene deletion analysis of the sphingolipid synthesis pathway in Fusarium graminearum, a causal agent of Fusarium head blight of wheat and other cereal crops worldwide. Mycelial growth assays showed that deletion of FgBAR1, FgLAC1, FgSUR2 or FgSCS7 resulted in markedly reduced hyphal growth. Fungicide sensitivity tests showed that the sphinganine C4-hydroxylase gene FgSUR2 deletion mutant (ΔFgSUR2) exhibited significantly increased susceptibility to azole fungicides. In addition, this mutant displayed a remarkable increase in cell membrane permeability. Importantly, ΔFgSUR2 was defective in deoxynivalenol (DON) toxisome formation, leading to dramatically decreased DON biosynthesis. Moreover, the deletion of FgSUR2 resulted in dramatically decreased virulence of the pathogen on host plants. Taken together, these results indicate that FgSUR2 plays an important role in regulating the susceptibility to azoles and virulence of F. graminearum.
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Affiliation(s)
- Haixia Wang
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yueqi Zhang
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Jingrui Wang
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yun Chen
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Tingjun Hou
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Youfu Zhao
- Irrigated Agriculture Research and Extension Center, Department of Plant Pathology, Washington State University, Prosser, WA 99350, USA
| | - Zhonghua Ma
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
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Matos GS, Madeira JB, Fernandes CM, Dasilva D, Masuda CA, Del Poeta M, Montero-Lomelí M. Regulation of sphingolipid synthesis by the G1/S transcription factor Swi4. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158983. [PMID: 34062255 PMCID: PMC8512607 DOI: 10.1016/j.bbalip.2021.158983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 11/23/2022]
Abstract
SBF (Swi4/Swi6 Binding Factor) complex is a crucial regulator of G1/S transition in Saccharomyces cerevisiae. Here, we show that SBF complex is required for myriocin resistance, an inhibitor of sphingolipid synthesis. This phenotype was not shared with MBF complex mutants nor with deletion of the Swi4p downstream targets, CLN1/CLN2. Based on data mining results, we selected putative Swi4p targets related to sphingolipid metabolism and studied their gene transcription as well as metabolite levels during progression of the cell cycle. Genes which encode key enzymes for the synthesis of long chain bases (LCBs) and ceramides were periodically transcribed during the mitotic cell cycle, having a peak at G1/S, and required SWI4 for full transcription at this stage. In addition, HPLC-MS/MS data indicated that swi4Δ cells have decreased levels of sphingolipids during progression of the cell cycle, particularly, dihydrosphingosine (DHS), C24-phytoceramides and C24-inositolphosphoryl ceramide (IPC) while it had increased levels of mannosylinositol phosphorylceramide (MIPC). Furthermore, we demonstrated that both inhibition of de novo sphingolipid synthesis by myriocin or SWI4 deletion caused partial arrest at the G2/M phase. Importantly, our lipidomic data demonstrated that the sphingolipid profile of WT cells treated with myriocin resembled that of swi4Δ cells, with lower levels of DHS, IPC and higher levels of MIPC. Taken together, these results show that SBF complex plays an essential role in the regulation of sphingolipid homeostasis, which reflects in the correct progression through the G2/M phase of the cell cycle.
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Affiliation(s)
- Gabriel S Matos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Juliana B Madeira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Deveney Dasilva
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA
| | - Claudio A Masuda
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA; Institute of Chemical Biology and Drug Discovery, Stony Brook University, Stony Brook, NY, USA; Veteran Administration Medical Center, Northport, NY, USA; MicroRid Technologies Inc., Dix Hills, NY, USA; Division of Infectious Diseases, School of Medicine, Stony Brook University, NY, USA
| | - Monica Montero-Lomelí
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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Maksimov AY, Balandina SY, Topanov PA, Mashevskaya IV, Chaudhary S. Organic Antifungal Drugs and Targets of Their Action. Curr Top Med Chem 2021; 21:705-736. [PMID: 33423647 DOI: 10.2174/1568026621666210108122622] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/20/2020] [Accepted: 09/03/2020] [Indexed: 11/22/2022]
Abstract
In recent decades, there has been a significant increase in the number of fungal diseases. This is due to a wide spectrum of action, immunosuppressants and other group drugs. In terms of frequency, rapid spread and globality, fungal infections are approaching acute respiratory infections. Antimycotics are medicinal substances endorsed with fungicidal or fungistatic properties. For the treatment of fungal diseases, several groups of compounds are used that differ in their origin (natural or synthetic), molecular targets and mechanism of action, antifungal effect (fungicidal or fungistatic), indications for use (local or systemic infections), and methods of administration (parenteral, oral, outdoor). Several efforts have been made by various medicinal chemists around the world for the development of antifungal drugs with high efficacy with the least toxicity and maximum selectivity in the area of antifungal chemotherapy. The pharmacokinetic properties of the new antimycotics are also important: the ability to penetrate biological barriers, be absorbed and distributed in tissues and organs, get accumulated in tissues affected by micromycetes, undergo drug metabolism in the intestinal microflora and human organs, and in the kinetics of excretion from the body. There are several ways to search for new effective antimycotics: - Obtaining new derivatives of the already used classes of antimycotics with improved activity properties. - Screening of new chemical classes of synthetic antimycotic compounds. - Screening of natural compounds. - Identification of new unique molecular targets in the fungal cell. - Development of new compositions and dosage forms with effective delivery vehicles. The methods of informatics, bioinformatics, genomics and proteomics were extensively investigated for the development of new antimycotics. These techniques were employed in finding and identification of new molecular proteins in a fungal cell; in the determination of the selectivity of drugprotein interactions, evaluation of drug-drug interactions and synergism of drugs; determination of the structure-activity relationship (SAR) studies; determination of the molecular design of the most active, selective and safer drugs for the humans, animals and plants. In medical applications, the methods of information analysis and pharmacogenomics allow taking into account the individual phenotype of the patient, the level of expression of the targets of antifungal drugs when choosing antifungal agents and their dosage. This review article incorporates some of the most significant studies covering the basic structures and approaches for the synthesis of antifungal drugs and the directions for their further development.
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Affiliation(s)
- Alexander Yu Maksimov
- Department of Pharmacy and Pharmacology, Faculty of Chemistry, Perm State University, Perm 614990, Russian Federation
| | - Svetlana Yu Balandina
- Department of Pharmacy and Pharmacology, Faculty of Chemistry, Perm State University, Perm 614990, Russian Federation
| | - Pavel A Topanov
- Department of Pharmacy and Pharmacology, Faculty of Chemistry, Perm State University, Perm 614990, Russian Federation
| | - Irina V Mashevskaya
- Department of Pharmacy and Pharmacology, Faculty of Chemistry, Perm State University, Perm 614990, Russian Federation
| | - Sandeep Chaudhary
- Laboratory of Organic and Medicinal Chemistry (OMC lab), Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jawaharlal Nehru Marg, Jaipur 302017, India
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7
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Han C, Jang M, Kim MJ, Han MH, Lee KR, Hahn JS, Ahn J. Engineering Yarrowia lipolytica for de novo production of tetraacetyl phytosphingosine. J Appl Microbiol 2020; 130:1981-1992. [PMID: 33190388 DOI: 10.1111/jam.14931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 10/15/2020] [Accepted: 11/04/2020] [Indexed: 11/26/2022]
Abstract
AIMS To genetically engineer the oleaginous yeast Yarrowia lipolytica for de novo production of tetraacetylphytosphingosine (TAPS), a precursor of phytosphingosine, and optimization of fermentation conditions for high yield. METHODS AND RESULTS We successfully constructed a TAPS-producing Y. lipolytica CE3 strain by co-expression of Wickerhamomyces ciferrii-derived acetyl transferases, Sli1p and Atf2p. Next, we optimized several environmental factors including temperature, initial pH and C/N ratio for TAPS production in a shake culture. Deletion of LCB4 in CE3 strain increased the volumetric TAPS titre and cell-specific yield to 142·1 ± 10·7 mgTAPS l-1 and 3·08 ± 0·11 mgTAPS gDCW -1 , respectively, in a shake flask culture incubated for 120 h at 28°C with glycerol as the carbon source. Finally, we developed a 5-l fed-batch process with NaOH-mediated pH control and olive oil as a carbon source, exhibiting 650 ± 24 mgTAPS l-1 of TAPS production within 56 h of the fermentation. CONCLUSIONS The introduction of codon-optimized Sli1p and Atf2p, deletion of LCB4 gene and sexual hybridization, accompanied by specific fermentation conditions, enhanced TAPS yield in Y. lipolytica. SIGNIFICANCE AND IMPACT OF THE STUDY Our results highlight Y. lipolytica as a promising candidate for the industrial production of TAPS, an important component of cosmetic formulations.
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Affiliation(s)
- Changpyo Han
- Biotechnology Process Engineering Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea.,Interdisciplinary Program for Bioengineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Minjeong Jang
- Biotechnology Process Engineering Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea
| | - Min Ju Kim
- Laboratory Animal Resource Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea
| | - Man-Ho Han
- Biotechnology Process Engineering Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea.,KRIBB School of Biotechnology, UST, Daejeon, Republic of Korea
| | - Kyeong-Ryoon Lee
- Laboratory Animal Resource Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea
| | - Ji-Sook Hahn
- Interdisciplinary Program for Bioengineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea.,School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea
| | - Jungoh Ahn
- Biotechnology Process Engineering Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea.,KRIBB School of Biotechnology, UST, Daejeon, Republic of Korea
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Nishimura S, Matsumori N. Chemical diversity and mode of action of natural products targeting lipids in the eukaryotic cell membrane. Nat Prod Rep 2020; 37:677-702. [PMID: 32022056 DOI: 10.1039/c9np00059c] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Covering: up to 2019Nature furnishes bioactive compounds (natural products) with complex chemical structures, yet with simple, sophisticated molecular mechanisms. When natural products exhibit their activities in cells or bodies, they first have to bind or react with a target molecule in/on the cell. The cell membrane is a major target for bioactive compounds. Recently, our understanding of the molecular mechanism of interactions between natural products and membrane lipids progressed with the aid of newly-developed analytical methods. New technology reconnects old compounds with membrane lipids, while new membrane-targeting molecules are being discovered through the screening for antimicrobial potential of natural products. This review article focuses on natural products that bind to eukaryotic membrane lipids, and includes clinically important molecules and key research tools. The chemical diversity of membrane-targeting natural products and the molecular basis of lipid recognition are described. The history of how their mechanism was unveiled, and how these natural products are used in research are also mentioned.
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Affiliation(s)
- Shinichi Nishimura
- Department of Biotechnology, Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo 113-8657, Japan.
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Sinha S, Nge CE, Leong CY, Ng V, Crasta S, Alfatah M, Goh F, Low KN, Zhang H, Arumugam P, Lezhava A, Chen SL, Kanagasundaram Y, Ng SB, Eisenhaber F, Eisenhaber B. Genomics-driven discovery of a biosynthetic gene cluster required for the synthesis of BII-Rafflesfungin from the fungus Phoma sp. F3723. BMC Genomics 2019; 20:374. [PMID: 31088369 PMCID: PMC6518819 DOI: 10.1186/s12864-019-5762-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 05/02/2019] [Indexed: 12/20/2022] Open
Abstract
Background Phomafungin is a recently reported broad spectrum antifungal compound but its biosynthetic pathway is unknown. We combed publicly available Phoma genomes but failed to find any putative biosynthetic gene cluster that could account for its biosynthesis. Results Therefore, we sequenced the genome of one of our Phoma strains (F3723) previously identified as having antifungal activity in a high-throughput screen. We found a biosynthetic gene cluster that was predicted to synthesize a cyclic lipodepsipeptide that differs in the amino acid composition compared to Phomafungin. Antifungal activity guided isolation yielded a new compound, BII-Rafflesfungin, the structure of which was determined. Conclusions We describe the NRPS-t1PKS cluster ‘BIIRfg’ compatible with the synthesis of the cyclic lipodepsipeptide BII-Rafflesfungin [HMHDA-L-Ala-L-Glu-L-Asn-L-Ser-L-Ser-D-Ser-D-allo-Thr-Gly]. We report new Stachelhaus codes for Ala, Glu, Asn, Ser, Thr, and Gly. We propose a mechanism for BII-Rafflesfungin biosynthesis, which involves the formation of the lipid part by BIIRfg_PKS followed by activation and transfer of the lipid chain by a predicted AMP-ligase on to the first PCP domain of the BIIRfg_NRPS gene. Electronic supplementary material The online version of this article (10.1186/s12864-019-5762-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Swati Sinha
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore.
| | - Choy-Eng Nge
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Chung Yan Leong
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Veronica Ng
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Sharon Crasta
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Mohammad Alfatah
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Falicia Goh
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Kia-Ngee Low
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Huibin Zhang
- Genome Institue of Singapore (GIS), Agency for Science, Technology and Research (A*STAR), 60 Biopolis Street, #02-01 Genome, Singapore, 138672, Republic of Singapore
| | - Prakash Arumugam
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Alexander Lezhava
- Genome Institue of Singapore (GIS), Agency for Science, Technology and Research (A*STAR), 60 Biopolis Street, #02-01 Genome, Singapore, 138672, Republic of Singapore
| | - Swaine L Chen
- Genome Institue of Singapore (GIS), Agency for Science, Technology and Research (A*STAR), 60 Biopolis Street, #02-01 Genome, Singapore, 138672, Republic of Singapore.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 10, Singapore, 119228, Republic of Singapore
| | - Yoganathan Kanagasundaram
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Siew Bee Ng
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Frank Eisenhaber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore.,School of Computer Science and Engineering (SCSE), Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Republic of Singapore
| | - Birgit Eisenhaber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore.
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10
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Martins TS, Costa V, Pereira C. Signaling pathways governing iron homeostasis in budding yeast. Mol Microbiol 2018; 109:422-432. [DOI: 10.1111/mmi.14009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Telma S. Martins
- I3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
| | - Vítor Costa
- I3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Departamento de Biologia Molecular; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto; Porto Portugal
| | - Clara Pereira
- I3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Departamento de Biologia Molecular; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto; Porto Portugal
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Ren J, Saied EM, Zhong A, Snider J, Ruiz C, Arenz C, Obeid LM, Girnun GD, Hannun YA. Tsc3 regulates SPT amino acid choice in Saccharomyces cerevisiae by promoting alanine in the sphingolipid pathway. J Lipid Res 2018; 59:2126-2139. [PMID: 30154231 DOI: 10.1194/jlr.m088195] [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: 07/02/2018] [Revised: 08/15/2018] [Indexed: 12/11/2022] Open
Abstract
The generation of most sphingolipids (SPLs) starts with condensation between serine and an activated long-chain fatty acid catalyzed by serine palmitoyltransferase (SPT). SPT can also use other amino acids to generate small quantities of noncanonical SPLs. The balance between serine-derived and noncanonical SPLs is pivotal; for example, hereditary sensory and autonomic neuropathy type I results from SPT mutations that cause an abnormal accumulation of alanine-derived SPLs. The regulatory mechanism for SPT amino acid selectivity and physiological functions of noncanonical SPLs are unknown. We investigated SPT selection of amino acid substrates by measuring condensation products of serine and alanine in yeast cultures and SPT use of serine and alanine in a TSC3 knockout model. We identified the Tsc3 subunit of SPT as a regulator of amino acid substrate selectivity by demonstrating its primary function in promoting alanine utilization by SPT and confirmed its requirement for the inhibitory effect of alanine on SPT utilization of serine. Moreover, we observed downstream metabolic consequences to Tsc3 loss: serine influx into the SPL biosynthesis pathway increased through Ypk1-depenedent activation of SPT and ceramide synthases. This Ypk1-dependent activation of serine influx after Tsc3 knockout suggests a potential function for deoxy-sphingoid bases in modulating Ypk1 signaling.
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Affiliation(s)
- Jihui Ren
- Department of Medicine, Stony Brook University, Stony Brook, NY
| | - Essa M Saied
- Institute for Chemistry, Humboldt University of Berlin, Berlin, Germany.,Department of Chemistry, Faculty of Science, Suez Canal University, Ismailia, Egypt
| | - Aaron Zhong
- Department of Medicine, Stony Brook University, Stony Brook, NY
| | - Justin Snider
- Department of Medicine, Stony Brook University, Stony Brook, NY
| | - Christian Ruiz
- Department of Pathology, Stony Brook University, Stony Brook, NY
| | - Christoph Arenz
- Institute for Chemistry, Humboldt University of Berlin, Berlin, Germany
| | - Lina M Obeid
- Department of Medicine, Stony Brook University, Stony Brook, NY.,Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY.,Northport Veterans Affairs Medical Center, Northport, NY
| | - Geoffrey D Girnun
- Department of Pathology, Stony Brook University, Stony Brook, NY.,Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY
| | - Yusuf A Hannun
- Department of Medicine, Stony Brook University, Stony Brook, NY .,Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY
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12
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Marquês JT, Marinho HS, de Almeida RF. Sphingolipid hydroxylation in mammals, yeast and plants – An integrated view. Prog Lipid Res 2018; 71:18-42. [DOI: 10.1016/j.plipres.2018.05.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/11/2018] [Accepted: 05/04/2018] [Indexed: 02/07/2023]
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13
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Subedi YP, AlFindee MN, Takemoto JY, Chang CWT. Antifungal amphiphilic kanamycins: new life for an old drug. MEDCHEMCOMM 2018; 9:909-919. [PMID: 30108980 PMCID: PMC6071784 DOI: 10.1039/c8md00155c] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 04/15/2018] [Indexed: 11/21/2022]
Abstract
Classical aminoglycoside antibiotics are obsolete or hampered by the emergence of drug resistant bacteria. Recent discoveries of antifungal amphiphilic kanamycins offer new strategies for reviving and repurposing these old drugs. A simple structural modification turns the clinically obsolete antibacterial kanamycin into an antifungal agent. Structure-activity relationship studies have led to the production of K20, an antifungal kanamycin that can be mass-produced for uses in agriculture as well as in animals. This review delineates the path to the discovery of K20 and other related antifungal amphiphilic kanamycins, determination of its mode of action, and findings in greenhouse and field trials with K20 that could lead to crop disease protection strategies.
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Affiliation(s)
- Yagya Prasad Subedi
- Department of Chemistry and Biochemistry , Utah State University , 0300 Old Main Hill , Logan , Utah 84322-0300 , USA .
| | - Madher N AlFindee
- Department of Chemistry and Biochemistry , Utah State University , 0300 Old Main Hill , Logan , Utah 84322-0300 , USA .
| | - Jon Y Takemoto
- Department of Biology , Utah State University , 5305 Old Main Hill , Logan , Utah 84322-5305 , USA
| | - Cheng-Wei Tom Chang
- Department of Chemistry and Biochemistry , Utah State University , 0300 Old Main Hill , Logan , Utah 84322-0300 , USA .
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14
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Martins TS, Pereira C, Canadell D, Vilaça R, Teixeira V, Moradas-Ferreira P, de Nadal E, Posas F, Costa V. The Hog1p kinase regulates Aft1p transcription factor to control iron accumulation. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:61-70. [DOI: 10.1016/j.bbalip.2017.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/15/2017] [Accepted: 10/09/2017] [Indexed: 12/22/2022]
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15
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Sphingolipids from the human fungal pathogen Aspergillus fumigatus. Biochimie 2017; 141:9-15. [PMID: 28652019 DOI: 10.1016/j.biochi.2017.06.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/21/2017] [Indexed: 01/24/2023]
Abstract
Sphingolipids (SPLs) are key components of the plasma membrane in yeast and filamentous fungi. These molecules are involved in a number of cellular processes, and particularly, SGLs are essential components of the highly polarized fungal growth where they are required for the formation of the polarisome organization at the hyphal apex. Aspergillus fumigatus, a human fungal pathogen, produce SGLs that are discriminated into neutral cerebrosides, glycosylinositolphosphoceramides (GIPCs) and glycosylphosphatidylinositol (GPI) anchors. In addition to complex hydrophilic head groups of GIPCs, A. fumigatus is, to date, the sole fungus that produces a GPI-anchored polysaccharide. These SPLs follow three different biosynthetic pathways. Genetics blockage leading to the inhibition of any SPL biosynthesis or to the alteration of the structure of SPL induces growth and virulence defects. The complete lipid moiety of SPLs is essential for the lipid microdomain organization and their biosynthetic pathways are potential antifungal targets but remains understudied.
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16
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Toume M, Tani M. Yeast lacking the amphiphysin family protein Rvs167 is sensitive to disruptions in sphingolipid levels. FEBS J 2016; 283:2911-28. [PMID: 27312128 DOI: 10.1111/febs.13783] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/23/2016] [Accepted: 06/15/2016] [Indexed: 12/13/2022]
Abstract
Rvs167 and Rvs161 in Saccharomyces cerevisiae are amphiphysin family proteins, which are involved in several important cellular events, such as invagination and scission of endocytic vesicles, and actin cytoskeleton organization. It has been reported that cellular dysfunctions caused by deletion of RVS167 or RVS161 are rescued by deletion of specific nonessential sphingolipid-metabolizing enzyme genes. Here, we found that yeast cells lacking RVS167 or RVS161 exhibit a decrease in sphingolipid levels. In rvs167∆ cells, the expression level of Orm2, a negative regulator of serine palmitoyltransferase (SPT) catalyzing the initial step of sphingolipid biosynthesis, was increased in a calcineurin-dependent manner, and the decrease in sphingolipid levels in rvs167∆ cells was reversed on deletion of ORM2. Moreover, repression of both ORM1 and ORM2 expression or overexpression of SPT caused a strong growth defect of rvs167∆ cells, indicating that enhancement of de novo sphingolipid biosynthesis is detrimental to rvs167∆ cells. In contrast, partial repression of LCB1-encoding SPT suppressed abnormal phenotypes caused by the deletion of RVS167, including supersensitivity to high temperature and salt stress, and impairment of endocytosis and actin cytoskeleton organization. In addition, the partial repression of SPT activity suppressed the temperature supersensitivity and abnormal vacuolar morphology caused by deletion of VPS1 encoding a dynamin-like GTPase, which is required for vesicle scission and is functionally closely related to Rvs167/Rvs161, whereas repression of both ORM1 and ORM2 expression in vps1∆ cells caused a growth defect. Thus, it was suggested that proper regulation of SPT activity is indispensable for amphiphysin-deficient cells.
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Affiliation(s)
- Moeko Toume
- Department of Chemistry, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Motohiro Tani
- Department of Chemistry, Faculty of Sciences, Kyushu University, Fukuoka, Japan
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17
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Abstract
Sphingolipids, a once overlooked class of lipids in plants, are now recognized as abundant and essential components of plasma membrane and other endomembranes of plant cells. In addition to providing structural integrity to plant membranes, sphingolipids contribute to Golgi trafficking and protein organizational domains in the plasma membrane. Sphingolipid metabolites have also been linked to the regulation of cellular processes, including programmed cell death. Advances in mass spectrometry-based sphingolipid profiling and analyses of Arabidopsis mutants have enabled fundamental discoveries in sphingolipid structural diversity, metabolism, and function that are reviewed here. These discoveries are laying the groundwork for the tailoring of sphingolipid biosynthesis and catabolism for improved tolerance of plants to biotic and abiotic stresses.
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Affiliation(s)
- Kyle D Luttgeharm
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska-Lincoln, E318 Beadle Center, 1901 Vine Street, Lincoln, NE, 68588, USA
| | - Athen N Kimberlin
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska-Lincoln, E318 Beadle Center, 1901 Vine Street, Lincoln, NE, 68588, USA
| | - Edgar B Cahoon
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska-Lincoln, E318 Beadle Center, 1901 Vine Street, Lincoln, NE, 68588, USA.
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18
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Tani M. Structure–Function Relationship of Complex Sphingolipids in Yeast. TRENDS GLYCOSCI GLYC 2016. [DOI: 10.4052/tigg.1509.1j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Motohiro Tani
- Department of Chemistry, Faculty of Sciences, Kyushu University
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19
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Affiliation(s)
- Motohiro Tani
- Department of Chemistry, Faculty of Sciences, Kyushu University
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20
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Two types of syringomycin E channels in sphingomyelin-containing bilayers. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2015; 45:91-8. [DOI: 10.1007/s00249-015-1101-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 10/19/2015] [Accepted: 11/11/2015] [Indexed: 10/22/2022]
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21
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Metabolic Conversion of Ceramides in HeLa Cells - A Cholesteryl Phosphocholine Delivery Approach. PLoS One 2015; 10:e0143385. [PMID: 26599810 PMCID: PMC4658033 DOI: 10.1371/journal.pone.0143385] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 11/04/2015] [Indexed: 11/19/2022] Open
Abstract
Ceramides can be delivered to cultured cells without solvents in the form of complexes with cholesteryl phosphocholine. We have analysed the delivery of three different radiolabeled D-erythro-ceramides (C6-Cer, C10-Cer and C16-Cer) to HeLa cells, and followed their metabolism as well as the cell viability. We found that all three ceramides were successfully taken up by HeLa cells when complexed to CholPC in an equimolar ratio, and show that the ceramides show different rates of cellular uptake and metabolic fate. The C6-Cer had the highest incorporation rate, followed by C10-Cer and C16-Cer, respectively. The subsequent effect on cell viability strongly correlated with the rate of incorporation, where C6-Cer had the strongest apoptotic effects. Low-dose (1 μM) treatment with C6-Cer favoured conversion of the precursor to sphingomyelin, whereas higher concentrations (25–100 μM) yielded increased conversion to C6-glucosylceramide. Similar results were obtained for C10-Cer. In the lower-dose C16-Cer experiments, most of the precursor was degraded, whereas at high-dose concentrations the precursor remained un-metabolized. Using this method, we demonstrate that ceramides with different chain lengths clearly exhibit varying rates of cellular uptake. The cellular fate of the externally delivered ceramides are clearly connected to their rate of incorporation and their subsequent effects on cell viability may be in part determined by their chain length.
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22
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23
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Modifiers of membrane dipole potentials as tools for investigating ion channel formation and functioning. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 315:245-97. [PMID: 25708465 DOI: 10.1016/bs.ircmb.2014.12.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electrostatic fields generated on and within biological membranes play a fundamental role in key processes in cell functions. The role of the membrane dipole potential is of particular interest because of its powerful impact on membrane permeability and lipid-protein interactions, including protein insertion, oligomerization, and function. The membrane dipole potential is defined by the orientation of electric dipoles of lipid headgroups, fatty acid carbonyl groups, and membrane-adsorbed water. As a result, the membrane interior is several hundred millivolts more positive than the external aqueous phase. This potential decrease depends on the lipid, and especially sterol, composition of the membrane. The adsorption of certain electroneutral molecules known as dipole modifiers may also lead to significant changes in the magnitude of the potential decrease. These agents are widely used to study the effects of the dipole potential on membrane transport. This review presents a critical analysis of a variety of data from studies dedicated to ion channel formation and functioning in membranes with different dipole potentials. The types of ion channels found in cellular membranes and pores formed by antimicrobial agents and toxins in artificial lipid membranes are summarized. The mechanisms underlying the influence of the membrane dipole potential on ion channel activity, including dipole-dipole and charge-dipole interactions in the pores and in membranes, are discussed. A hypothesis, in which lipid rafts in both model and cellular membranes also modulate ion channel activity by virtue of an increased or decreased dipole potential, is also considered.
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24
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Shrestha SK, Chang CWT, Meissner N, Oblad J, Shrestha JP, Sorensen KN, Grilley MM, Takemoto JY. Antifungal amphiphilic aminoglycoside K20: bioactivities and mechanism of action. Front Microbiol 2014; 5:671. [PMID: 25538692 PMCID: PMC4257101 DOI: 10.3389/fmicb.2014.00671] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 11/18/2014] [Indexed: 02/05/2023] Open
Abstract
K20 is a novel amphiphilic antifungal aminoglycoside that is synthetically derived from the antibiotic kanamycin A. Reported here are investigations of K20's antimicrobial activities, cytotoxicity, and fungicidal mechanism of action. In vitro growth inhibitory activities against a variety of human and plant pathogenic yeasts, filamentous fungi, and bacteria were determined using microbroth dilution assays and time-kill curve analyses, and hemolytic and animal cell cytotoxic activities were determined. Effects on Cryptococcus neoformans H-99 infectivity were determined with a preventive murine lung infection model. The antifungal mechanism of action was studied using intact fungal cells, yeast lipid mutants, and small unilamellar lipid vesicles. K20 exhibited broad-spectrum in vitro antifungal activities but not antibacterial activities. Pulmonary, single dose-administration of K20 reduced C. neoformans lung infection rates 4-fold compared to controls. Hemolysis and half-maximal cytotoxicities of mammalian cells occurred at concentrations that were 10 to 32-fold higher than fungicidal MICs. With fluorescein isothiocyanate (FITC), 20-25 mg/L K20 caused staining of >95% of C. neoformans and Fusarium graminearum cells and at 31.3 mg/L caused rapid leakage (30-80% in 15 min) of calcein from preloaded small unilamellar lipid vesicles. K20 appears to be a broad-spectrum fungicide, capable of reducing the infectivity of C. neoformans, and exhibits low hemolytic activity and mammalian cell toxicity. It perturbs the plasma membrane by mechanisms that are lipid modulated. K20 is a novel amphiphilic aminoglycoside amenable to scalable production and a potential lead antifungal for therapeutic and crop protection applications.
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Affiliation(s)
- Sanjib K Shrestha
- Department of Biology, Utah State University Logan, UT, USA ; Synthetic Bioproducts Center, Utah State University North Logan, UT, USA
| | - Cheng-Wei T Chang
- Synthetic Bioproducts Center, Utah State University North Logan, UT, USA ; Department of Chemistry and Biochemistry, Utah State University Logan, UT, USA
| | - Nicole Meissner
- Department of Immunology and Infectious Diseases, Montana State University Bozeman, MT, USA
| | - John Oblad
- Department of Chemistry and Biochemistry, Utah State University Logan, UT, USA
| | - Jaya P Shrestha
- Department of Chemistry and Biochemistry, Utah State University Logan, UT, USA
| | | | | | - Jon Y Takemoto
- Department of Biology, Utah State University Logan, UT, USA ; Synthetic Bioproducts Center, Utah State University North Logan, UT, USA
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25
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Toume M, Tani M. Change in activity of serine palmitoyltransferase affects sensitivity to syringomycin E in yeastSaccharomyces cerevisiae. FEMS Microbiol Lett 2014; 358:64-71. [DOI: 10.1111/1574-6968.12535] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 07/03/2014] [Accepted: 07/04/2014] [Indexed: 11/28/2022] Open
Affiliation(s)
- Moeko Toume
- Department of Chemistry; Faculty of Sciences; Kyushu University; Higashi-ku Fukuoka Japan
| | - Motohiro Tani
- Department of Chemistry; Faculty of Sciences; Kyushu University; Higashi-ku Fukuoka Japan
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26
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Zavala E, Marquez-Lago TT. The long and viscous road: uncovering nuclear diffusion barriers in closed mitosis. PLoS Comput Biol 2014; 10:e1003725. [PMID: 25032937 PMCID: PMC4102450 DOI: 10.1371/journal.pcbi.1003725] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 06/02/2014] [Indexed: 11/18/2022] Open
Abstract
Diffusion barriers are effective means for constraining protein lateral exchange in cellular membranes. In Saccharomyces cerevisiae, they have been shown to sustain parental identity through asymmetric segregation of ageing factors during closed mitosis. Even though barriers have been extensively studied in the plasma membrane, their identity and organization within the nucleus remains poorly understood. Based on different lines of experimental evidence, we present a model of the composition and structural organization of a nuclear diffusion barrier during anaphase. By means of spatial stochastic simulations, we propose how specialised lipid domains, protein rings, and morphological changes of the nucleus may coordinate to restrict protein exchange between mother and daughter nuclear lobes. We explore distinct, plausible configurations of these diffusion barriers and offer testable predictions regarding their protein exclusion properties and the diffusion regimes they generate. Our model predicts that, while a specialised lipid domain and an immobile protein ring at the bud neck can compartmentalize the nucleus during early anaphase; a specialised lipid domain spanning the elongated bridge between lobes would be entirely sufficient during late anaphase. Our work shows how complex nuclear diffusion barriers in closed mitosis may arise from simple nanoscale biophysical interactions. Spatial segregation of molecular contents is often necessary for an accurate, timely accomplishment of cellular functions, such as signal transduction and cell-fate decisions. For instance, budding yeast division requires the asymmetric segregation of proteins to distinguish a newborn cell from its parent. However, the strategies to achieve this parental identity are poorly understood. This holds especially true for key proteins and molecular complexes involved in mitosis that diffuse within the nuclear envelope. In fact, segregation within the nuclear envelope has been experimentally verified, but both the nature and configuration of any plausible diffusion barrier remain unknown. In this work, we built virtual models of the nucleus and carried out simulations testing the plausibility of specialised lipid domains and protein rings constituting the diffusion barrier. Moreover, we explored distinct barrier configurations in early and late stages of cell division, and verified our simulation results match experimental observations. Our work shows that the biophysical properties of these molecules, coordinated with morphological changes in the nucleus, make them suitable components of the nuclear diffusion barrier. Importantly, our research approach offers a novel avenue to study diffusion barriers in other biological membranes.
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Affiliation(s)
- Eder Zavala
- Integrative Systems Biology Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
| | - Tatiana T. Marquez-Lago
- Integrative Systems Biology Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
- * E-mail:
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27
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Spincemaille P, Matmati N, Hannun YA, Cammue BPA, Thevissen K. Sphingolipids and mitochondrial function in budding yeast. Biochim Biophys Acta Gen Subj 2014; 1840:3131-7. [PMID: 24973565 DOI: 10.1016/j.bbagen.2014.06.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 05/09/2014] [Accepted: 06/19/2014] [Indexed: 02/07/2023]
Abstract
BACKGROUND Sphingolipids (SLs) are not only key components of cellular membranes, but also play an important role as signaling molecules in orchestrating both cell growth and apoptosis. In Saccharomyces cerevisiae, three complex SLs are present and hydrolysis of either of these species is catalyzed by the inositol phosphosphingolipid phospholipase C (Isc1p). Strikingly, mutants deficient in Isc1p display several hallmarks of mitochondrial dysfunction such as the inability to grow on a non-fermentative carbon course, increased oxidative stress and aberrant mitochondrial morphology. SCOPE OF REVIEW In this review, we focus on the pivotal role of Isc1p in regulating mitochondrial function via SL metabolism, and on Sch9p as a central signal transducer. Sch9p is one of the main effectors of the target of rapamycin complex 1 (TORC1), which is regarded as a crucial signaling axis for the regulation of Isc1p-mediated events. Finally, we describe the retrograde response, a signaling event originating from mitochondria to the nucleus, which results in the induction of nuclear target genes. Intriguingly, the retrograde response also interacts with SL homeostasis. MAJOR CONCLUSIONS All of the above suggests a pivotal signaling role for SLs in maintaining correct mitochondrial function in budding yeast. GENERAL SIGNIFICANCE Studies with budding yeast provide insight on SL signaling events that affect mitochondrial function.
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Affiliation(s)
- Pieter Spincemaille
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium
| | - Nabil Matmati
- Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Yusuf A Hannun
- Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Bruno P A Cammue
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium; Department of Plant Systems Biology, VIB, Technologiepark 927, 9052 Ghent, Belgium.
| | - Karin Thevissen
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium
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28
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Lindfors E, Jouhten P, Oja M, Rintala E, Orešič M, Penttilä M. Integration of transcription and flux data reveals molecular paths associated with differences in oxygen-dependent phenotypes of Saccharomyces cerevisiae. BMC SYSTEMS BIOLOGY 2014; 8:16. [PMID: 24528924 PMCID: PMC3930817 DOI: 10.1186/1752-0509-8-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Accepted: 02/07/2014] [Indexed: 11/17/2022]
Abstract
BACKGROUND Saccharomyces cerevisiae is able to adapt to a wide range of external oxygen conditions. Previously, oxygen-dependent phenotypes have been studied individually at the transcriptional, metabolite, and flux level. However, the regulation of cell phenotype occurs across the different levels of cell function. Integrative analysis of data from multiple levels of cell function in the context of a network of several known biochemical interaction types could enable identification of active regulatory paths not limited to a single level of cell function. RESULTS The graph theoretical method called Enriched Molecular Path detection (EMPath) was extended to enable integrative utilization of transcription and flux data. The utility of the method was demonstrated by detecting paths associated with phenotype differences of S. cerevisiae under three different conditions of oxygen provision: 20.9%, 2.8% and 0.5%. The detection of molecular paths was performed in an integrated genome-scale metabolic and protein-protein interaction network. CONCLUSIONS The molecular paths associated with the phenotype differences of S. cerevisiae under conditions of different oxygen provisions revealed paths of molecular interactions that could potentially mediate information transfer between processes that respond to the particular oxygen availabilities.
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Affiliation(s)
- Erno Lindfors
- VTT Technical Research Centre of Finland, Espoo, Finland
- Currently at: LifeGlimmer GmbH, Markelstrasse 38, D–12136 Berlin, Germany
- Currently at: Chemistry Building, Building 316, Dreijenplein 10, 6703 HB Wageningen, The Netherlands
| | - Paula Jouhten
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Merja Oja
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Eija Rintala
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Matej Orešič
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Merja Penttilä
- VTT Technical Research Centre of Finland, Espoo, Finland
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29
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Montefusco DJ, Matmati N, Hannun YA. The yeast sphingolipid signaling landscape. Chem Phys Lipids 2014; 177:26-40. [PMID: 24220500 PMCID: PMC4211598 DOI: 10.1016/j.chemphyslip.2013.10.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 10/18/2013] [Accepted: 10/19/2013] [Indexed: 12/13/2022]
Abstract
Sphingolipids are recognized as signaling mediators in a growing number of pathways, and represent potential targets to address many diseases. The study of sphingolipid signaling in yeast has created a number of breakthroughs in the field, and has the potential to lead future advances. The aim of this article is to provide an inclusive view of two major frontiers in yeast sphingolipid signaling. In the first section, several key studies in the field of sphingolipidomics are consolidated to create a yeast sphingolipidome that ranks nearly all known sphingolipid species by their level in a resting yeast cell. The second section presents an overview of most known phenotypes identified for sphingolipid gene mutants, presented with the intention of illuminating not yet discovered connections outside and inside of the field.
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Affiliation(s)
- David J Montefusco
- Dept. Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States.
| | - Nabil Matmati
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, United States
| | - Yusuf A Hannun
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, United States.
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30
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Shrestha S, Grilley M, Fosso MY, Chang CWT, Takemoto JY. Membrane lipid-modulated mechanism of action and non-cytotoxicity of novel fungicide aminoglycoside FG08. PLoS One 2013; 8:e73843. [PMID: 24040088 PMCID: PMC3769384 DOI: 10.1371/journal.pone.0073843] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 07/27/2013] [Indexed: 11/30/2022] Open
Abstract
A novel aminoglycoside, FG08, that differs from kanamycin B only by a C8 alkyl chain at the 4″-O position, was previously reported. Unlike kanamycin B, FG08 shows broad-spectrum fungicidal but not anti-bacterial activities. To understand its specificity for fungi, the mechanism of action of FG08 was studied using intact cells of the yeast Saccharomyces cerevisiae and small unilamellar membrane vesicles. With exposure to FG08 (30 µg mL−1), 8-fold more cells were stained with fluorescein isothiocyanate, cells had 4 to 6-fold higher K+ efflux rates, and 18-fold more cells were stained with SYTOX Green in comparison to exposure to kanamycin B (30 µg mL−1). Yeast mutants with aberrant membrane sphingolipids (no sphingoid base C4 hydroxyl group, truncated very long fatty acid chain, or lacking the terminal phosphorylinositol group of mannosyl-diinositolphosphorylphytoceramide were 4 to 8-fold less susceptible to growth inhibition with FG08 and showed 2 to 10-fold lower SYTOX Green dye uptake rates than did the isogenic wild-type strain. FG08 caused leakage of pre-loaded calcein from 50% of small unilamellar vesicles with glycerophospholipid and sterol compositions that mimic the compositions of fungal plasma membranes. Less than 5 and 10% of vesicles with glycerophospholipid and sterol compositions that mimic bacterial and mammalian cell plasma membranes, respectively, showed calcein leakage. In tetrazolium dye cytotoxicity tests, mammalian cell lines NIH3T3 and C8161.9 showed FG08 toxicity at concentrations that were 10 to 20-fold higher than fungicidal minimal inhibitory concentrations. It is concluded that FG08’s growth inhibitory specificity for fungi lie in plasma membrane permeability changes involving mechanisms that are modulated by membrane lipid composition.
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Affiliation(s)
- Sanjib Shrestha
- Department of Biology, Utah State University, Logan, Utah, United States of America
- Synthetic Bioproducts Center (USTAR), Utah State University, North Logan, Utah, United States of America
| | - Michelle Grilley
- Department of Biology, Utah State University, Logan, Utah, United States of America
| | - Marina Y. Fosso
- Department of Chemistry and Biochemistry, Logan, Utah, United States of America
| | - Cheng-Wei T. Chang
- Department of Chemistry and Biochemistry, Logan, Utah, United States of America
| | - Jon Y. Takemoto
- Department of Biology, Utah State University, Logan, Utah, United States of America
- * E-mail:
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A novel Sit4 phosphatase complex is involved in the response to ceramide stress in yeast. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:129645. [PMID: 24082981 PMCID: PMC3777123 DOI: 10.1155/2013/129645] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/28/2013] [Accepted: 07/25/2013] [Indexed: 12/17/2022]
Abstract
Ceramide is a building block for complex sphingolipids in the plasma membrane, but it also plays a significant role in secondary signalling pathways regulating cell proliferation and apoptosis in response to stress. Ceramide activated protein phosphatase activity has been previously observed in association with the Sit4 protein phosphatase. Here we find that sit4Δ mutants have decreased ceramide levels and display resistance to exogenous ceramides and phytosphingosine. Mutants lacking SIT4 or KTI12 display a shift towards nonhydroxylated forms of long chain bases and sphingolipids, suggesting regulation of hydroxylase (SUR2) or ceramide synthase by Sit4p. We have identified novel subunits of the Sit4 complex and have also shown that known Sit4 regulatory subunits—SAP proteins—are not involved in the ceramide response. This is the first observation of separation of function between Sit4 and SAP proteins. We also find that the Sit4p target Elongator is not involved in the ceramide response but that cells deficient in Kti12p—an accessory protein with an undefined regulatory role—have similar ceramide phenotypes to sit4Δ mutants. Therefore, Kti12p may play a similar secondary role in the ceramide response. This evidence points to a novel Sit4-dependent regulatory mechanism in response to ceramide stress.
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Bojsen R, Torbensen R, Larsen CE, Folkesson A, Regenberg B. The synthetic amphipathic peptidomimetic LTX109 is a potent fungicide that disturbs plasma membrane integrity in a sphingolipid dependent manner. PLoS One 2013; 8:e69483. [PMID: 23874964 PMCID: PMC3709891 DOI: 10.1371/journal.pone.0069483] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 06/10/2013] [Indexed: 02/06/2023] Open
Abstract
The peptidomimetic LTX109 (arginine-tertbutyl tryptophan-arginine-phenylethan) was previously shown to have antibacterial properties. Here, we investigated the activity of this novel antimicrobial peptidomimetic on the yeast Saccharomyces cerevisiae. We found that LTX109 was an efficient fungicide that killed all viable cells in an exponentially growing population as well as a large proportion of cells in biofilm formed on an abiotic surface. LTX109 had similar killing kinetics to the membrane-permeabilizing fungicide amphotericin B, which led us to investigate the ability of LTX109 to disrupt plasma membrane integrity. S. cerevisiae cells exposed to a high concentration of LTX109 showed rapid release of potassium and amino acids, suggesting that LTX109 acted by destabilizing the plasma membrane. This was supported by the finding that cells were permeable to the fluorescent nucleic acid stain SYTOX Green after a few minutes of LTX109 treatment. We screened a haploid S. cerevisiae gene deletion library for mutants resistant to LTX109 to uncover potential molecular targets. Eight genes conferred LTX109 resistance when deleted and six were involved in the sphingolipid biosynthetic pathway (SUR1, SUR2, SKN1, IPT1, FEN1 and ORM2). The involvement of all of these genes in the biosynthetic pathway for the fungal-specific lipids mannosylinositol phosphorylceramide (MIPC) and mannosyl di-(inositol phosphoryl) ceramide (M(IP)2C) suggested that these lipids were essential for LTX109 sensitivity. Our observations are consistent with a model in which LTX109 kills S. cerevisiae by nonspecific destabilization of the plasma membrane through direct or indirect interaction with the sphingolipids.
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Affiliation(s)
- Rasmus Bojsen
- Department of Systems Biology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Rasmus Torbensen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Anders Folkesson
- Department of Systems Biology, Technical University of Denmark, Kgs. Lyngby, Denmark
- Section for Bacteriology, Pathology and Parasitology, National Veterinary Institute, Frederiksberg C, Denmark
| | - Birgitte Regenberg
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
- * E-mail:
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Biotechnological production of sphingoid bases and their applications. Appl Microbiol Biotechnol 2013; 97:4301-8. [DOI: 10.1007/s00253-013-4878-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/22/2013] [Accepted: 03/22/2013] [Indexed: 12/14/2022]
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Singh SB, Ondeyka J, Harris G, Herath K, Zink D, Vicente F, Bills G, Collado J, Platas G, González del Val A, Martin J, Reyes F, Wang H, Kahn JN, Galuska S, Giacobbe R, Abruzzo G, Roemer T, Xu D. Isolation, structure, and biological activity of Phaeofungin, a cyclic lipodepsipeptide from a Phaeosphaeria sp. Using the Genome-Wide Candida albicans Fitness Test. JOURNAL OF NATURAL PRODUCTS 2013; 76:334-345. [PMID: 23259972 DOI: 10.1021/np300704s] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Phaeofungin (1), a new cyclic depsipeptide isolated from Phaeosphaeria sp., was discovered by application of reverse genetics technology, using the Candida albicans fitness test (CaFT). Phaeofungin is comprised of seven amino acids and a β,γ-dihydroxy-γ-methylhexadecanoic acid arranged in a 25-membered cyclic depsipeptide. Five of the amino acids were assigned with d-configurations. The structure was elucidated by 2D-NMR and HRMS-MS analysis of the natural product and its hydrolyzed linear peptide. The absolute configuration of the amino acids was determined by Marfey's method by complete and partial hydrolysis of 1. The CaFT profile of the phaeofungin-containing extract overlapped with that of phomafungin (3), another structurally different cyclic lipodepsipeptide isolated from a Phoma sp. using the same approach. Comparative biological characterization further demonstrated that these two fungal lipodepsipeptides are functionally distinct. While phomafungin was potentiated by cyclosporin A (an inhibitor of the calcineurin pathway), phaeofungin was synergized with aureobasidin A (2) (an inhibitor of the sphingolipid biosynthesis) and to some extent caspofungin (an inhibitor of glucan synthase). Furthermore, phaeofungin caused ATP release in wild-type C. albicans strains but phomafungin did not. It showed modest antifungal activity against C. albicans (MIC 16-32 μg/mL) and better activity against Aspergillus fumigatus (MIC 8-16 μg/mL) and Trichophyton mentagrophytes (MIC 4 μg/mL). The linear peptide was inactive, suggesting that the macrocyclic depsipeptide ring is essential for target engagement and antifungal activity.
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Affiliation(s)
- Sheo B Singh
- Department of Medicinal Chemistry, Merck Research Laboratories , PO Box 2000, Rahway, New Jersey 07065, USA.
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Lester RL, Withers BR, Schultz MA, Dickson RC. Iron, glucose and intrinsic factors alter sphingolipid composition as yeast cells enter stationary phase. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:726-36. [PMID: 23286903 DOI: 10.1016/j.bbalip.2012.12.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 12/11/2012] [Accepted: 12/19/2012] [Indexed: 11/24/2022]
Abstract
Survival of Saccharomyces cerevisiae cells, like most microorganisms, requires switching from a rapidly dividing to a non-dividing or stationary state. To further understand how cells navigate this switch, we examined sphingolipids since they are key structural elements of membranes and also regulate signaling pathways vital for survival. During and after the switch to a non-dividing state there is a large increase in total free and sphingolipid-bound long chain-bases and an even larger increase in free and bound C20-long-chain bases, which are nearly undetectable in dividing cells. These changes are due to intrinsic factors including Orm1 and Orm2, ceramide synthase, Lcb4 kinase and the Tsc3 subunit of serine palmitoyltransferase as well as extrinsic factors including glucose and iron. Lowering the concentration of glucose, a form of calorie restriction, decreases the level of LCBs, which is consistent with the idea that reducing the level of some sphingolipids enhances lifespan. In contrast, iron deprivation increases LCB levels and decreases long term survival; however, these phenomena may not be related because iron deprivation disrupts many metabolic pathways. The correlation between increased LCBs and shorter lifespan is unsupported at this time. The physiological rise in LCBs that we observe may serve to modulate nutrient transporters and possibly other membrane phenomena that contribute to enhanced stress resistance and survival in stationary phase.
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Affiliation(s)
- Robert L Lester
- Department of Molecular and Cellular Biochemistry and the Lucille Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
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Börgel D, van den Berg M, Hüller T, Andrea H, Liebisch G, Boles E, Schorsch C, van der Pol R, Arink A, Boogers I, van der Hoeven R, Korevaar K, Farwick M, Köhler T, Schaffer S. Metabolic engineering of the non-conventional yeast Pichia ciferrii for production of rare sphingoid bases. Metab Eng 2012; 14:412-26. [PMID: 22449569 DOI: 10.1016/j.ymben.2012.03.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2011] [Revised: 02/19/2012] [Accepted: 03/09/2012] [Indexed: 12/13/2022]
Abstract
The study describes the identification of sphingolipid biosynthesis genes in the non-conventional yeast Pichia ciferrii, the development of tools for its genetic modification as well as their application for metabolic engineering of P. ciferrii with the goal to generate strains capable of producing the rare sphingoid bases sphinganine and sphingosine. Several canonical genes encoding ceramide synthase (encoded by PcLAG1 and PcLAF1), alkaline ceramidase (PcYXC1) and sphingolipid C-4-hydroxylase(PcSYR2), as well as structural genes for dihydroceramide Δ(4)-desaturase (PcDES1) and sphingolipid Δ(8)-desaturase (PcSLD1) were identified, indicating that P. ciferrii would be capable of synthesizing desaturated sphingoid bases, a property not ubiquitously found in yeasts. In order to convert the phytosphingosine-producing P. ciferrii wildtype into a strain capable of producing predominantly sphinganine, Syringomycin E-resistant mutants were isolated. A stable mutant almost exclusively producing high levels of acetylated sphinganine was obtained and used as the base strain for further metabolic engineering. A metabolic pathway required for the three-step conversion of sphinganine to sphingosine was implemented in the sphinganine producing P. ciferrii strain and subsequently enhanced by screening for the appropriate heterologous enzymes, improvement of gene expression and codon optimization. These combined efforts led to a strain capable of producing 240mgL(-1) triacetyl sphingosine in shake flask, with tri- and diacetyl sphinganine being the main by-products. Lab-scale fermentation of this strain resulted in production of up to 890mgkg(-1) triacetyl sphingosine. A third by-product was unequivocally identified as triacetyl sphingadienine. It could be shown that inactivation of the SLD1 gene in P. ciferrii efficiently suppresses triacetyl sphingadienine formation. Further improvement of the described P. ciferrii strains will enable a biotechnological route to produce sphinganine and sphingosine for cosmetic and pharmaceutical applications.
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Affiliation(s)
- Daniel Börgel
- Evonik Degussa, Project House ProFerm, Creavis Technologies & Innovation, Rodenbacher Chaussee 4, D-63457 Hanau, Germany.
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Alvarez-Vasquez F, Riezman H, Hannun YA, Voit EO. Mathematical modeling and validation of the ergosterol pathway in Saccharomyces cerevisiae. PLoS One 2011; 6:e28344. [PMID: 22194828 PMCID: PMC3237449 DOI: 10.1371/journal.pone.0028344] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Accepted: 11/06/2011] [Indexed: 11/22/2022] Open
Abstract
The de novo biosynthetic machinery for both sphingolipid and ergosterol production in yeast is localized in the endoplasmic reticulum (ER) and Golgi. The interconnections between the two pathways are still poorly understood, but they may be connected in specialized membrane domains, and specific knockouts strongly suggest that both routes have different layers of mutual control and are co-affected by drugs. With the goal of shedding light on the functional integration of the yeast sphingolipid-ergosterol (SL-E) pathway, we constructed a dynamic model of the ergosterol pathway using the guidelines of Biochemical Systems Theory (BST) (Savageau., J. theor. Biol., 25, 365–9, 1969). The resulting model was merged with a previous mathematical model of sphingolipid metabolism in yeast (Alvarez-Vasquez et al., J. theor. Biol., 226, 265–91, 2004; Alvarez-Vasquez et al., Nature433, 425–30, 2005). The S-system format within BST was used for analyses of consistency, stability, and sensitivity of the SL-E model, while the GMA format was used for dynamic simulations and predictions. Model validation was accomplished by comparing predictions from the model with published results on sterol and sterol-ester dynamics in yeast. The validated model was used to predict the metabolomic dynamics of the SL-E pathway after drug treatment. Specifically, we simulated the action of drugs affecting sphingolipids in the endoplasmic reticulum and studied changes in ergosterol associated with microdomains of the plasma membrane (PM).
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Affiliation(s)
- Fernando Alvarez-Vasquez
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America.
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Bensaci MF, Gurnev PA, Bezrukov SM, Takemoto JY. Fungicidal Activities and Mechanisms of Action of Pseudomonas syringae pv. syringae Lipodepsipeptide Syringopeptins 22A and 25A. Front Microbiol 2011; 2:216. [PMID: 22046175 PMCID: PMC3201023 DOI: 10.3389/fmicb.2011.00216] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 10/11/2011] [Indexed: 11/13/2022] Open
Abstract
The plant-associated bacterium Pseudomonas syringae pv. syringae simultaneously produces two classes of metabolites: the small cyclic lipodepsinonapeptides such as the syringomycins and the larger cyclic lipodepsipeptide syringopeptins SP22 or SP25. The syringomycins inhibit a broad spectrum of fungi (but particularly yeasts) by lipid-dependent membrane interaction. The syringopeptins are phytotoxic and inhibitory to Gram-positive bacteria. In this study, the fungicidal activities of two major syringopeptins, SP22A and SP25A, and their mechanisms of action were investigated and compared to those of syringomycin E. SP22A and SP25A were observed to inhibit the fungal yeasts Saccharomyces cerevisiae and Candida albicans although less effectively than syringomycin E. S. cerevisiae mutants defective in ergosterol and sphingolipid biosyntheses were less susceptible to SP22A and SP25A but the relative inhibitory capabilities of SRE vs. SP22A and SP25A were maintained. Similar differences were observed for capabilities to cause cellular K(+) and Ca(2+) fluxes in S. cerevisiae. Interestingly, in phospholipid bilayers the syringopeptins are found to induce larger macroscopic ionic conductances than syringomycin E but form single channels with similar properties. These findings suggest that the syringopeptins target the yeast plasma membrane, and, like syringomycin E, employ a lipid-dependent channel-forming mechanism of action. The differing degrees of growth inhibition by these lipodepsipeptides may be explained by differences in their hydrophobicities. The more hydrophobic SP22A and SP25A might interact more strongly with the yeast cell wall that would create a selective barrier for their incorporation into the plasma membrane.
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Abstract
Intensive research over the past 2 decades has implicated ceramide in the regulation of several cell responses. However, emerging evidence points to dramatic complexities in ceramide metabolism and structure that defy the prevailing unifying hypothesis on ceramide function that is based on the understanding of ceramide as a single entity. Here, we develop the concept that "ceramide" constitutes a family of closely related molecules, subject to metabolism by >28 enzymes and with >200 structurally distinct mammalian ceramides distinguished by specific structural modifications. These ceramides are synthesized in a combinatorial fashion with distinct enzymes responsible for the specific modifications. These multiple pathways of ceramide generation led to the hypothesis that individual ceramide molecular species are regulated by specific biochemical pathways in distinct subcellular compartments and execute distinct functions. In this minireview, we describe the "many ceramides" paradigm, along with the rationale, supporting evidence, and implications for our understanding of bioactive sphingolipids and approaches for unraveling these pathways.
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Affiliation(s)
- Yusuf A Hannun
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SouthCarolina 29425, USA.
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Anselmi M, Eliseo T, Zanetti-Polzi L, Fullone MR, Fogliano V, Di Nola A, Paci M, Grgurina I. Structure of the lipodepsipeptide syringomycin E in phospholipids and sodium dodecylsulphate micelle studied by circular dichroism, NMR spectroscopy and molecular dynamics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2102-10. [PMID: 21658366 DOI: 10.1016/j.bbamem.2011.04.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 04/22/2011] [Accepted: 04/25/2011] [Indexed: 10/18/2022]
Abstract
Syringomycin E (SRE) is a member of a family of lipodepsipeptides that characterize the secondary metabolism of the plant-associated bacteria Pseudomonas syringae pv. syringae. It displays phytotoxic, antifungal and haemolytic activities, due to the membrane interaction and ion channel formation. To gain an insight into the conformation of SRE in the membrane environment, we studied the conformation of SRE bound to SDS micelle, a suitable model for the membrane-bound SRE. In fact, highly similar circular dichroism (CD) spectra were obtained for SRE bound to sodium dodecylsulphate (SDS) and to a phospholipid bilayer, indicating the conformational equivalence of SRE in these two media, at difference with the CD spectrum of SRE in water solution. The structure of SDS-bound SRE was determined by NMR spectroscopy combined with molecular dynamics calculations in octane environment. The results of this study highlight the influence of the interaction with lipids in determining the three-dimensional structure of SRE and provide the basis for further investigations on structural determinants of syringomycin E-membrane interaction.
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Moreno-Pérez AJ, Martínez-Force E, Garcés R, Salas JJ. Sphingolipid base modifying enzymes in sunflower (Helianthus annuus): cloning and characterization of a C4-hydroxylase gene and a new paralogous Δ8-desaturase gene. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:831-839. [PMID: 21256623 DOI: 10.1016/j.jplph.2010.11.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 11/04/2010] [Accepted: 11/04/2010] [Indexed: 05/30/2023]
Abstract
Sphingolipids are components of plant cell membranes that participate in the regulation of important physiological processes. Unlike their animal counterparts, plant sphingolipids are characterized by high levels of base C4-hydroxylation. Moreover, desaturation at the Δ8 position predominates over the Δ4 desaturation typically found in animal sphingolipids. These modifications are due to the action of C4-hydroxylases and Δ8-long chain base desaturases, and they are important for complex sphingolipids finally becoming functional. The long chain bases of sunflower sphingolipids have high levels of hydroxylated and unsaturated moieties. Here, a C4-long chain base hydroxylase was functionally characterized in sunflower plant, an enzyme that could complement the sur2Δ mutation when heterologously expressed in this yeast mutant deficient in hydroxylation. This hydroxylase was ubiquitously expressed in sunflower, with the highest levels found in the developing cotyledons. In addition, we identified a new Δ8-long base chain desaturase gene that displays strong homology to a previously reported desaturase gene. This desaturase was also expressed in yeast and was able to change the long chain base composition of the transformed host. We studied the expression of this desaturase and compared it with that of the other isoform described in sunflower. The desaturase form studied in this paper displayed higher expression levels in developing seeds.
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Koeller CM, Heise N. The Sphingolipid Biosynthetic Pathway Is a Potential Target for Chemotherapy against Chagas Disease. Enzyme Res 2011; 2011:648159. [PMID: 21603271 PMCID: PMC3092604 DOI: 10.4061/2011/648159] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 02/17/2011] [Accepted: 02/25/2011] [Indexed: 12/23/2022] Open
Abstract
The protozoan parasite Trypanosoma cruzi is the causative agent of human Chagas disease, for which there currently is no cure. The life cycle of T. cruzi is complex, including an extracellular phase in the triatomine insect vector and an obligatory intracellular stage inside the vertebrate host. These phases depend on a variety of surface glycosylphosphatidylinositol-(GPI-) anchored glycoconjugates that are synthesized by the parasite. Therefore, the surface expression of GPI-anchored components and the biosynthetic pathways of GPI anchors are attractive targets for new therapies for Chagas disease. We identified new drug targets for chemotherapy by taking the available genome sequence information and searching for differences in the sphingolipid biosynthetic pathways (SBPs) of mammals and T. cruzi. In this paper, we discuss the major steps of the SBP in mammals, yeast and T. cruzi, focusing on the IPC synthase and ceramide remodeling of T. cruzi as potential therapeutic targets for Chagas disease.
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Affiliation(s)
- Carolina Macedo Koeller
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Centro de Ciências da Saúde, Bloco G-019, Cidade Universitária-Ilha do Fundão, 21941-902 Rio de Janeiro RJ, Brazil
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Effects of expression of lcb1/lcb2 and lac1/lag1 genes on the biosynthesis of ceramides. BIOTECHNOL BIOPROC E 2011. [DOI: 10.1007/s12257-010-0268-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Ternes P, Wobbe T, Schwarz M, Albrecht S, Feussner K, Riezman I, Cregg JM, Heinz E, Riezman H, Feussner I, Warnecke D. Two pathways of sphingolipid biosynthesis are separated in the yeast Pichia pastoris. J Biol Chem 2011; 286:11401-14. [PMID: 21303904 DOI: 10.1074/jbc.m110.193094] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although the yeast Saccharomyces cerevisiae has only one sphingolipid class with a head group based on phosphoinositol, the yeast Pichia pastoris as well as many other fungi have a second class, glucosylceramide, which has a glucose head group. These two sphingolipid classes are in addition distinguished by a characteristic structure of their ceramide backbones. Here, we investigate the mechanisms controlling substrate entry into the glucosylceramide branch of the pathway. By a combination of enzymatic in vitro studies and lipid analysis of genetically engineered yeast strains, we show that the ceramide synthase Bar1p occupies a key branching point in sphingolipid biosynthesis in P. pastoris. By preferring dihydroxy sphingoid bases and C(16)/C(18) acyl-coenzyme A as substrates, Bar1p produces a structurally well defined group of ceramide species, which is the exclusive precursor for glucosylceramide biosynthesis. Correlating with the absence of glucosylceramide in this yeast, a gene encoding Bar1p is missing in S. cerevisiae. We could not successfully investigate the second ceramide synthase in P. pastoris that is orthologous to S. cerevisiae Lag1p/Lac1p. By analyzing the ceramide and glucosylceramide species in a collection of P. pastoris knock-out strains in which individual genes encoding enzymes involved in glucosylceramide biosynthesis were systematically deleted, we show that the ceramide species produced by Bar1p have to be modified by two additional enzymes, sphingolipid Δ4-desaturase and fatty acid α-hydroxylase, before the final addition of the glucose head group by the glucosylceramide synthase. Together, this set of four enzymes specifically defines the pathway leading to glucosylceramide biosynthesis.
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Affiliation(s)
- Philipp Ternes
- Department of Plant Biochemistry, Albrecht von Haller Institute for Plant Sciences, Georg August University, Göttingen, Germany
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Dickson RC. Roles for sphingolipids in Saccharomyces cerevisiae. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 688:217-31. [PMID: 20919657 PMCID: PMC5612324 DOI: 10.1007/978-1-4419-6741-1_15] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Studies using Saccharomyces cerevisiae, the common baker's or brewer's yeast, have progressed over the past twenty years from knowing which sphingolipids are present in cells and a basic outline of how they are made to a complete or nearly complete directory of the genes that catalyze their anabolism and catabolism. In addition, cellular processes that depend upon sphingolipids have been identified including protein trafficking/exocytosis, endocytosis and actin cytoskeleton dynamics, membrane microdomains, calcium signaling, regulation of transcription and translation, cell cycle control, stress resistance, nutrient uptake and aging. These will be summarized here along with new data not previously reviewed. Advances in our knowledge of sphingolipids and their roles in yeast are impressive but molecular mechanisms remain elusive and are a primary challenge for further progress in understanding the specific functions of sphingolipids.
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Affiliation(s)
- Robert C Dickson
- Department of Molecular and Cellular Biochemistry, Lucille P. Markey Cancer Center, University of Kentucky College of Medicine, 741 S. Limestone St., BBSRB, 8173, Lexington, Kentucky 40536-0509, USA.
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Herath K, Harris G, Jayasuriya H, Zink D, Smith S, Vicente F, Bills G, Collado J, González A, Jiang B, Kahn JN, Galuska S, Giacobbe R, Abruzzo G, Hickey E, Liberator P, Xu D, Roemer T, Singh SB. Isolation, structure and biological activity of phomafungin, a cyclic lipodepsipeptide from a widespread tropical Phoma sp. Bioorg Med Chem 2008; 17:1361-9. [PMID: 19112025 DOI: 10.1016/j.bmc.2008.12.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 12/04/2008] [Accepted: 12/07/2008] [Indexed: 11/30/2022]
Abstract
We isolated a cyclic lipodepsipeptide, phomafungin, from a Phoma sp. The distinct antifungal activity of phomafungin in the crude extract was initially discovered by mechanistic profiling in the Candida albicans fitness test. The purified compound contains a 28 member ring consisting of eight amino acids and a beta-hydroxy-gamma-methyl-hexadecanoic acid, and displays a broad spectrum of antifungal activity against Candida spp., Aspergillus fumigatus and Trichophyton mentagrophytes with MIC of 2-8 microg/ml, and toxicity to mice at 25 mg/kg. The linear peptide derived from opening of the lactone ring was devoid of antifungal activity as well as toxicity. Phomafungin has been identified in a number of Phoma spp. collected from Africa and the Indian and Pacific Ocean islands.
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Affiliation(s)
- Kithsiri Herath
- Natural Products Chemistry, Merck Research Laboratories, Rahway, NJ 07065, USA
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Dickson RC. Thematic review series: sphingolipids. New insights into sphingolipid metabolism and function in budding yeast. J Lipid Res 2008; 49:909-21. [PMID: 18296751 DOI: 10.1194/jlr.r800003-jlr200] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Our understanding of sphingolipid metabolism and functions in the baker's yeast Saccharomyces cerevisiae has progressed substantially in the past 2 years. Yeast sphingolipids contain a C26-acyl moiety, all of the genes necessary to make these long-chain fatty acids have been identified, and a mechanism for how chain length is determined has been proposed. Advances in understanding how the de novo synthesis of ceramide and complex sphingolipids is regulated have been made, and they demonstrate that the Target Of Rapamycin Complex 2 (TORC2) controls ceramide synthase activity. Other work shows that TORC2 regulates the level of complex sphingolipids in a pathway using the Slm1 and Slm2 proteins to control the protein phosphatase calcineurin, which regulates the breakdown of complex sphingolipids. The activity of Slm1 and Slm2 has also been shown to be regulated during heat stress by phosphoinositides and TORC2, along with sphingoid long-chain bases and the Pkh1 and Pkh2 protein kinases, to control the actin cytoskeleton, the trafficking of nutrient transporters, and cell viability. Together, these results provide the first molecular insights into understanding previous genetic interaction data that indicated a connection between sphingolipids and the TORC2 and phosphoinositide signaling networks. This new knowledge provides a foundation for greatly advancing our understanding of sphingolipid biology in yeast.
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Affiliation(s)
- Robert C Dickson
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536-0509, USA.
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Chapter 3 Voltage‐Dependent Ion Channels Induced by Cyclic Lipodepsipeptides in Planar Lipid Bilayers. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s1554-4516(08)00203-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Imamura T, Kusano H, Kajigaya Y, Ichikawa M, Shimada H. A rice dihydrosphingosine C4 hydroxylase (DSH1) gene, which is abundantly expressed in the stigmas, vascular cells and apical meristem, may be involved in fertility. PLANT & CELL PHYSIOLOGY 2007; 48:1108-20. [PMID: 17609219 DOI: 10.1093/pcp/pcm084] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Dihydrosphingosine C4 hydroxylase is a key enzyme in the biosynthesis of phytosphingosine, a major constituent of sphingolipids in plants and yeasts. The rice genome contains five homologue genes for dihydrosphingosine C4 hydroxylase, DSH1-DSH5, whose gene products show high degrees of homology to the yeast counterpart, SUR2. Among them, expression of DSH1, DSH2 and DSH4 was detected, and DSH1 and DSH4 complement the yeast sur2 mutation. The DSH1 gene was specifically and abundantly expressed in vascular bundles and apical meristems. In particular, very strong expression was detected in the stigmas of flowers. Repression of DSH1 expression by the antisense gene or RNA interference (RNAi) resulted in a severe reduction of fertility. In the transformants in which DSH1 expression was suppressed, significantly increased expression of DSH2 was found in leaves but not in pistils, suggesting that there was tissue-specific correlation between DSH1 and DSH2 expression. Our results indicate that the product of DSH1 may be involved in plant viability or reproductive processes, and that the phenotype of sterility is apparently caused by loss of function of DSH1 in the stigma. It is also suggested that there is a complex mechanism controlling the tissue-specific expression of the DSH1 gene.
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Affiliation(s)
- Tomohiro Imamura
- Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan
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