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Schwechheimer SK, Becker J, Peyriga L, Portais JC, Wittmann C. Metabolic flux analysis in Ashbya gossypii using 13C-labeled yeast extract: industrial riboflavin production under complex nutrient conditions. Microb Cell Fact 2018; 17:162. [PMID: 30326916 PMCID: PMC6190667 DOI: 10.1186/s12934-018-1003-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 09/24/2018] [Indexed: 12/17/2022] Open
Abstract
Background The fungus Ashbya gossypii is an important industrial producer of the vitamin riboflavin. Using this microbe, riboflavin is manufactured in a two-stage process based on a rich medium with vegetable oil, yeast extract and different precursors: an initial growth and a subsequent riboflavin production phase. So far, our knowledge on the intracellular metabolic fluxes of the fungus in this complex process is limited, but appears highly relevant to better understand and rationally engineer the underlying metabolism. To quantify intracellular fluxes of growing and riboflavin producing A. gossypii, studies with different 13C tracers were embedded into a framework of experimental design, isotopic labeling analysis by MS and NMR techniques, and model-based data processing. The studies included the use 13C of yeast extract, a key component used in the process. Results During growth, the TCA cycle was found highly active, whereas the cells exhibited a low flux through gluconeogenesis as well as pentose phosphate pathway. Yeast extract was the main carbon donor for anabolism, while vegetable oil selectively contributed to the proteinogenic amino acids glutamate, aspartate, and alanine. During the subsequent riboflavin biosynthetic phase, the carbon flux through the TCA cycle remained high. Regarding riboflavin formation, most of the vitamin’s carbon originated from rapeseed oil (81 ± 1%), however extracellular glycine and yeast extract also contributed with 9 ± 0% and 8 ± 0%, respectively. In addition, advanced yeast extract-based building blocks such as guanine and GTP were directly incorporated into the vitamin. Conclusion Intracellular carbon fluxes for growth and riboflavin production on vegetable oil provide the first flux insight into a fungus on complex industrial medium. The knowledge gained therefrom is valuable for further strain and process improvement. Yeast extract, while being the main carbon source during growth, contributes valuable building blocks to the synthesis of vitamin B2. This highlights the importance of careful selection of the right yeast extract for a process based on its unique composition. Electronic supplementary material The online version of this article (10.1186/s12934-018-1003-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Judith Becker
- Institute of Systems Biotechnology, Saarland University, Campus A1.5, 66123, Saarbrücken, Germany
| | - Lindsay Peyriga
- Université de Toulouse, INSA, UPS, INP, Toulouse, France.,INRA, UMR792 Ingénerie des Systèmes Biologiques et des Procédés, Toulouse, France.,CNRS, UMR5504, Toulouse, France
| | - Jean-Charles Portais
- Université de Toulouse, INSA, UPS, INP, Toulouse, France.,INRA, UMR792 Ingénerie des Systèmes Biologiques et des Procédés, Toulouse, France.,CNRS, UMR5504, Toulouse, France
| | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, Campus A1.5, 66123, Saarbrücken, Germany.
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Biotechnology of riboflavin. Appl Microbiol Biotechnol 2016; 100:2107-19. [DOI: 10.1007/s00253-015-7256-z] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/14/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
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Aguiar TQ, Silva R, Domingues L. Ashbya gossypii beyond industrial riboflavin production: A historical perspective and emerging biotechnological applications. Biotechnol Adv 2015; 33:1774-86. [DOI: 10.1016/j.biotechadv.2015.10.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/28/2015] [Accepted: 10/04/2015] [Indexed: 10/22/2022]
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Aguiar TQ, Ribeiro O, Arvas M, Wiebe MG, Penttilä M, Domingues L. Investigation of protein secretion and secretion stress in Ashbya gossypii. BMC Genomics 2014; 15:1137. [PMID: 25523110 PMCID: PMC4320514 DOI: 10.1186/1471-2164-15-1137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 11/20/2014] [Indexed: 11/27/2022] Open
Abstract
Background Ashbya gossypii is a filamentous Saccharomycete used for the industrial production of riboflavin that has been recently explored as a host system for recombinant protein production. To gain insight into the protein secretory pathway of this biotechnologically relevant fungus, we undertook genome-wide analyses to explore its secretome and its transcriptional responses to protein secretion stress. Results A computational pipeline was used to predict the inventory of proteins putatively secreted by A. gossypii via the general secretory pathway. The proteins actually secreted by this fungus into the supernatants of submerged cultures in minimal and rich medium were mapped by two-dimensional gel electrophoresis, revealing that most of the A. gossypii secreted proteins have an isoelectric point between 4 and 6, and a molecular mass above 25 kDa. These analyses together indicated that 1-4% of A. gossypii proteins are likely to be secreted, of which less than 33% are putative hydrolases. Furthermore, transcriptomic analyses carried out in A. gossypii cells under recombinant protein secretion conditions and dithiothreitol-induced secretion stress unexpectedly revealed that a conventional unfolded protein response (UPR) was not activated in any of the conditions, as the expression levels of several well-known UPR target genes (e.g. IRE1, KAR2, HAC1 and PDI1 homologs) remained unaffected. However, several other genes involved in protein unfolding, endoplasmatic reticulum-associated degradation, proteolysis, vesicle trafficking, vacuolar protein sorting, secretion and mRNA degradation were up-regulated by dithiothreitol-induced secretion stress. Conversely, the transcription of several genes encoding secretory proteins, such as components of the glycosylation pathway, was severely repressed by dithiothreitol Conclusions This study provides the first insights into the secretion stress response of A. gossypii, as well as a basic understanding of its protein secretion potential, which is more similar to that of yeast than to that of other filamentous fungi. Contrary to what has been widely described for yeast and fungi, a conventional UPR was not observed in A. gossypii, but alternative protein quality control mechanisms enabled it to cope with secretion stress. These data will help provide strategies for improving heterologous protein secretion in A. gossypii. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1137) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | - Lucília Domingues
- CEB - Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
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Dry entrapment of enzymes by epoxy or polyester resins hardened on different solid supports. Enzyme Microb Technol 2014; 60:47-55. [PMID: 24835099 DOI: 10.1016/j.enzmictec.2014.03.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 03/06/2014] [Accepted: 03/29/2014] [Indexed: 01/06/2023]
Abstract
Embedding of enzymes was performed with epoxy or polyester resin by mixing in a dried enzyme preparation before polymerization was started. This fast and low-cost immobilization method produced enzymatically active layers on different solid supports. As model enzymes the well-characterized Thermomyces lanuginosus lipase and a new threonine aldolase from Ashbya gossypii were used. It was shown that T. lanuginosus lipase recombinantly expressed in Aspergillus oryzae is a monomeric enzyme with a molecular mass of 34kDa, while A. gossypii threonine aldolase expressed in Escherichia coli is a pyridoxal-5'-phosphate binding homotetramer with a mass of 180kDa. The enzymes were used freeze dried, in four different preparations: freely diffusing, adsorbed on octyl sepharose, as well as cross-linked enzyme aggregates or as suspensions in organic solvent. They were mixed with standard two-component resins and prepared as layers on solid supports made of different materials e.g. metal, glass, polyester. Polymerization led to encapsulated enzyme preparations showing activities comparable to literature values.
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Aguiar TQ, Dinis C, Magalhães F, Oliveira C, Wiebe MG, Penttilä M, Domingues L. Molecular and Functional Characterization of an Invertase Secreted by Ashbya gossypii. Mol Biotechnol 2014; 56:524-34. [DOI: 10.1007/s12033-013-9726-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Magalhães F, Aguiar TQ, Oliveira C, Domingues L. High-level expression ofAspergillus nigerβ-galactosidase inAshbya gossypii. Biotechnol Prog 2014; 30:261-68. [DOI: 10.1002/btpr.1844] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Frederico Magalhães
- IBB-Ins. for Biotechnology and Bioengineering; Centre of Biological Engineering, Universidade do Minho; Campus de Gualtar 4710-057 Braga Portugal
| | - Tatiana Q. Aguiar
- IBB-Ins. for Biotechnology and Bioengineering; Centre of Biological Engineering, Universidade do Minho; Campus de Gualtar 4710-057 Braga Portugal
| | - Carla Oliveira
- IBB-Ins. for Biotechnology and Bioengineering; Centre of Biological Engineering, Universidade do Minho; Campus de Gualtar 4710-057 Braga Portugal
| | - Lucília Domingues
- IBB-Ins. for Biotechnology and Bioengineering; Centre of Biological Engineering, Universidade do Minho; Campus de Gualtar 4710-057 Braga Portugal
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Eggersdorfer M, Laudert D, Létinois U, McClymont T, Medlock J, Netscher T, Bonrath W. Einhundert Jahre Vitamine - eine naturwissenschaftliche Erfolgsgeschichte. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201205886] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Eggersdorfer M, Laudert D, Létinois U, McClymont T, Medlock J, Netscher T, Bonrath W. One Hundred Years of Vitamins-A Success Story of the Natural Sciences. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/anie.201205886] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Garcia-Galan C, Berenguer-Murcia Á, Fernandez-Lafuente R, Rodrigues RC. Potential of Different Enzyme Immobilization Strategies to Improve Enzyme Performance. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100534] [Citation(s) in RCA: 1243] [Impact Index Per Article: 95.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Jurado E, García-Román M, Luzón G, Altmajer-Vaz D, Jiménez-Pérez JL. Optimization of Lipase Performance in Detergent Formulations for Hard Surfaces. Ind Eng Chem Res 2011. [DOI: 10.1021/ie201486a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Encarnación Jurado
- Chemical Engineering Department, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Miguel García-Román
- Chemical Engineering Department, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Germán Luzón
- Chemical Engineering Department, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Deisi Altmajer-Vaz
- Chemical Engineering Department, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - José Luis Jiménez-Pérez
- Chemical Engineering Department, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
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Barig S, Alisch R, Nieland S, Wuttke A, Gräser Y, Huddar M, Schnitzlein K, Stahmann KP. Monoseptic growth of fungal lipase producers under minimized sterile conditions: Cultivation of Phialemonium curvatum in 350 L scale. Eng Life Sci 2011. [DOI: 10.1002/elsc.201000219] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Morinaga N, Maeda A, Mizuno T, Bunya M, Sugihara S, Sugihara A. Synthesis of fatty acid sterol esters using cholesterol esterase from Trichoderma sp. AS59. Enzyme Microb Technol 2011; 48:498-504. [PMID: 22113022 DOI: 10.1016/j.enzmictec.2011.02.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 02/11/2011] [Accepted: 02/23/2011] [Indexed: 11/27/2022]
Abstract
We recently reported the characterization of novel cholesterol esterase (EC. 3.1.1.13) from Trichoderma sp. and preliminary work on sterol ester synthesis. In the present study, we further examined the enzyme ability to synthesize cholesterol esters from cholesterol and free fatty acids of various chain lengths, and compared the fatty acid specificity in synthesis with that in hydrolysis. The enzyme catalyzed the synthesis of medium- and long-chain fatty acid cholesterol esters, but failed to synthesize short-chain fatty acid esters. The fatty acid specificities in the synthesis and hydrolysis of cholesterol esters were entirely different from each other. Unlike other lipolytic enzymes, the enzyme was largely independent of water content in the synthesis of cholesterol oleate, and it achieved near-complete esterification in the presence of an equimolar excess of oleic acid. Of additional interest is the finding that the addition of n-hexane markedly enhanced the esterification activities on all the medium- and long-chain saturated fatty acids used. Based on these findings, we attempted to synthesize stigmasterol stearate as a food additive to lower cholesterol levels in blood plasma, and found that the enzyme catalyzed effective synthesis of the ester without the need of dehydration during the reaction, indicating the potential utility of the enzyme in the food industry.
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Affiliation(s)
- Naoya Morinaga
- Faculty of Engineering, Tokushima Bunri University, 1314-1 Shido, Sanuki 769-2193, Japan
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Ribeiro O, Wiebe M, Ilmén M, Domingues L, Penttilä M. Expression of Trichoderma reesei cellulases CBHI and EGI in Ashbya gossypii. Appl Microbiol Biotechnol 2010; 87:1437-46. [DOI: 10.1007/s00253-010-2610-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 04/08/2010] [Accepted: 04/09/2010] [Indexed: 12/17/2022]
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Importance of malate synthase in the glyoxylate cycle of Ashbya gossypii for the efficient production of riboflavin. Appl Microbiol Biotechnol 2009; 83:529-39. [PMID: 19343342 DOI: 10.1007/s00253-009-1972-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 03/18/2009] [Accepted: 03/19/2009] [Indexed: 10/21/2022]
Abstract
The glyoxylate cycle is an anabolic pathway that is necessary for growth on nonfermentable carbon sources such as vegetable oils and is important for riboflavin production by the filamentous fungus Ashbya gossypii. The aim of this study was to identify malate synthase in the glyoxylate cycle of A. gossypii and to investigate its importance in riboflavin production from rapeseed oil. The ACR268C gene was identified as the malate synthase gene that encoded functional malate synthase in the glyoxylate cycle. The ACR268C gene knockout mutant lost malate synthase activity, and its riboflavin production and oil consumption were 10- and 2-fold lower, respectively, than the values of the wild-type strain. In contrast, the ACR268C gene-overexpressing strain showed a 1.6-fold increase in the malate synthase activity and 1.7-fold higher riboflavin production than the control strain. These results demonstrate that the malate synthase in the glyoxylate cycle has an important role not only in riboflavin production but also in oil consumption.
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Dib I, Nidetzky B. The stabilizing effects of immobilization in D-amino acid oxidase from Trigonopsis variabilis. BMC Biotechnol 2008; 8:72. [PMID: 18798979 PMCID: PMC2557008 DOI: 10.1186/1472-6750-8-72] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Accepted: 09/17/2008] [Indexed: 11/29/2022] Open
Abstract
Background Immobilization of Trigonopsis variabilis D-amino acid oxidase (TvDAO) on solid support is the key to a reasonably stable performance of this enzyme in the industrial process for the conversion of cephalosporin C as well as in other biocatalytic applications. Results To provide a mechanistic basis for the stabilization of the carrier-bound oxidase we analyzed the stabilizing effects of immobilization in TvDAO exposed to the stress of elevated temperature and operational conditions. Two different strategies of immobilization were used: multi-point covalent binding to epoxy-activated Sepabeads EC-EP; and non-covalent oriented immobilization of the enzyme through affinity of its N-terminal Strep-tag to Strep-Tactin coated on insoluble particles. At 50°C, the oriented immobilizate was not stabilized as compared to the free enzyme. The structure of TvDAO was stabilized via covalent attachment to Sepabeads EC-EP but concomitantly, binding of the FAD cofactor was weakened. FAD release from the enzyme into solution markedly reduced the positive effect of immobilization on the overall stability of TvDAO. Under conditions of substrate conversion in a bubble-aerated stirred tank reactor, both immobilization techniques as well as the addition of the surfactant Pluronic F-68 stabilized TvDAO by protecting the enzyme from the deleterious effect of gas-liquid interfaces. Immobilization of TvDAO on Sepabeads EC-EP however stabilized the enzyme beyond this effect and led to a biocatalyst that could be re-used in multiple cycles of substrate conversion. Conclusion Multi-point covalent attachment of TvDAO on an isoluble porous carrier provides stabilization against the denaturing effects of high temperature and exposure to a gas-liquid interface. Improvement of binding of the FAD cofactor, probably by using methods of protein engineering, would further enhance the stability of the immobilized enzyme.
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Affiliation(s)
- Iskandar Dib
- Research Centre Applied Biocatalysis, Petersgasse 14, A-8010 Graz, Austria.
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Sharma R, Chisti Y, Banerjee UC. Production, purification, characterization, and applications of lipases. Biotechnol Adv 2004; 19:627-62. [PMID: 14550014 DOI: 10.1016/s0734-9750(01)00086-6] [Citation(s) in RCA: 749] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Lipases (triacylglycerol acylhydrolases, EC 3.1.1.3) catalyze the hydrolysis and the synthesis of esters formed from glycerol and long-chain fatty acids. Lipases occur widely in nature, but only microbial lipases are commercially significant. The many applications of lipases include speciality organic syntheses, hydrolysis of fats and oils, modification of fats, flavor enhancement in food processing, resolution of racemic mixtures, and chemical analyses. This article discusses the production, recovery, and use of microbial lipases. Issues of enzyme kinetics, thermostability, and bioactivity are addressed. Production of recombinant lipases is detailed. Immobilized preparations of lipases are discussed. In view of the increasing understanding of lipases and their many applications in high-value syntheses and as bulk enzymes, these enzymes are having an increasing impact on bioprocessing.
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Affiliation(s)
- R Sharma
- National Institute of Pharmaceutical Education and Research, Sector 67, SAS Nagar, Mohali, Punjab, India
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Mohanty M, Ghadge R, Patil N, Sawant S, Joshi J, Deshpande A. Deactivation of lipase at gas–liquid interface in stirred vessel. Chem Eng Sci 2001. [DOI: 10.1016/s0009-2509(01)00020-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lim SH, Choi JS, Park EY. Microbial production of riboflavin using riboflavin overproducers,Ashbya gossypii, Bacillus subtilis, andCandida famate: An overview. BIOTECHNOL BIOPROC E 2001. [DOI: 10.1007/bf02931951] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Maeting I, Schmidt G, Sahm H, Stahmann KP. Role of a peroxisomal NADP-specific isocitrate dehydrogenase in the metabolism of the riboflavin overproducer Ashbya gossypii. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s1381-1177(00)00135-1] [Citation(s) in RCA: 4] [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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Aguié-Béghin V, Leclerc E, Daoud M, Douillard R. Asymmetric Multiblock Copolymers at the Gas-Liquid Interface: Phase Diagram and Surface Pressure. J Colloid Interface Sci 1999; 214:143-155. [PMID: 10339355 DOI: 10.1006/jcis.1999.6144] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A theoretical model of copolymers made of N blocks is studied at the air-water interface. Each block is made of a sequence A of ZA hydrophobic and of a sequence B of ZB hydrophilic monomers. The A and B sequences cannot cross the interface. The conformation of an adsorbed polymer is determined as a random walk of N elements whose size is the Flory radius of a single sequence. The structure of the interfacial layer is determined as a function of alpha = ZA/ZB and of the surface concentration using scaling law arguments. Only three different regions are found in the phase diagram to describe the change of surface regime as a function of the total surface concentration. The energy of flower-like micelles of polymers is calculated and compared with the energy of adsorbed macromolecules in order to determine the surface concentration at saturation. The surface pressure is also calculated as a function of the surface concentration in the three different regions of the phase diagram. It is found that these surface pressure isotherms are not affected by the solvent quality except when the properties of the interfacial layer are dominated by a purely two-dimensional behavior (semidiluted regime of the whole polymer or of the A sequences on the air side of the interface). Finally the properties of this model are compared with experimental data obtained with protein adsorbed layers and encouraging agreement is found although proteins are much more complicated polymers than this crude model. Copyright 1999 Academic Press.
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Affiliation(s)
- V Aguié-Béghin
- Institut National de la Recherche Agronomique, Centre de Recherche Agronomique, 2 Esplanade Roland Garros, Reims Cedex 2, 51686, France
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Maeting I, Schmidt G, Sahm H, Revuelta JL, Stierhof YD, Stahmann KP. Isocitrate lyase of Ashbya gossypii--transcriptional regulation and peroxisomal localization. FEBS Lett 1999; 444:15-21. [PMID: 10037140 DOI: 10.1016/s0014-5793(99)00017-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The isocitrate lyase-encoding gene AgICL1 from the filamentous hemiascomycete Ashbya gossypii was isolated by heterologous complementation of a Saccharomyces cerevisiae icl1d mutant. The open reading frame of 1680 bp encoded a protein of 560 amino acids with a calculated molecular weight of 62584. Disruption of the AgICL1 gene led to complete loss of AgIcl1p activity and inability to grow on oleic acid as sole carbon source. Compartmentation of AgIcl1p in peroxisomes was demonstrated both by Percoll density gradient centrifugation and by immunogold labeling of ultrathin sections using specific antibodies. This fitted with the peroxisomal targeting signal AKL predicted from the C-terminal DNA sequence. Northern blot analysis with mycelium grown on different carbon sources as well as AgICL1 promoter replacement with the constitutive AgTEF promoter revealed a regulation at the transcriptional level. AgICL1 was subject to glucose repression, derepressed by glycerol, partially induced by the C2 compounds ethanol and acetate, and fully induced by soybean oil.
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Affiliation(s)
- I Maeting
- Institut für Biotechnologie 1, Forschungszentrum Jülich GmbH, Germany
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