References of "Fickers, Patrick"
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See detailInducible promoter for gene expression and synthetic biology
Nicaud, Jean-Marc; Trassaert, Marion; Thomas, Stéphane et al

Patent (in press)

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See detailUseful tools for genome editing in the non-conventional yeast Yarrowia lipolytica
Vandermies, Marie ULiege; Denies, Olivia ULiege; Nicaud, Jean-Marc et al

Poster (2017, September)

The non-conventional yeast Yarrowia lipolytica is increasingly used for the production of recombinant proteins or biomolecules with biotechnological or pharmaceutical applications. The development of such ... [more ▼]

The non-conventional yeast Yarrowia lipolytica is increasingly used for the production of recombinant proteins or biomolecules with biotechnological or pharmaceutical applications. The development of such a cell factory requires steps of genome editing that rely on selectable markers. The recently identified EYK1, encoding erythrulose kinase, can serve as an efficient catabolic selectable marker for genome editing in Y. lipolytica. Besides, the cloning-free strategy developed here simplifies the construction of disruption cassettes for genome editing in Y. lipolytica. [less ▲]

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See detailNew filamentous mutant of Yarrowia lipolytica and its use in biofilm bioreactors
Vandermies, Marie ULiege; Kar, Tambi ULiege; Denies, Olivia ULiege et al

Poster (2017, September)

The non-conventional yeast Yarrowia lipolytica is widely investigated for its unusual metabolic properties. Among them is the ability of Y. lipolytica to adopt an ovoid or hyphal morphology according to ... [more ▼]

The non-conventional yeast Yarrowia lipolytica is widely investigated for its unusual metabolic properties. Among them is the ability of Y. lipolytica to adopt an ovoid or hyphal morphology according to environmental conditions. The mechanism of dimorphic transition involves numerous genes, which have been poorly documented to date. Here, we report on the isolation of a filamentous mutant from an insertion mutagenesis library, the subsequent identification of the mutated gene, and the use of this filamentous mutant in biofilm bioreactors. [less ▲]

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See detailEYK1 encoding erythrulose kinase as a catabolic selectable marker for genome editing in the non-conventional yeast Yarrowia lipolytica
Vandermies, Marie ULiege; Denies, Olivia ULiege; Nicaud, Jean-Marc et al

in Journal of Microbiological Methods (2017), 139

We report here on EYK1, encoding erythrulose kinase, as an efficient catabolic selectable marker for genome editing in Y. lipolytica. Compared to auxotrophic markers, EYK1 increases the growth rate of ... [more ▼]

We report here on EYK1, encoding erythrulose kinase, as an efficient catabolic selectable marker for genome editing in Y. lipolytica. Compared to auxotrophic markers, EYK1 increases the growth rate of transformants and allows improved efficiency of transformation. The utility of the marker EYK1 in a replicative vector was also demonstrated. [less ▲]

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See detailEnhancing erythritol productivity in Yarrowia lipolytica using metabolic engineering
Carly, Frédéric; Vandermies, Marie ULiege; Telek, Samuel ULiege et al

in Metabolic Engineering (2017), 42

Erythritol (1,2,3,4-butanetetrol) is a four-carbon sugar alcohol with sweetening properties that is used by the agrofood industry as a food additive. In this study, we demonstrated that metabolic ... [more ▼]

Erythritol (1,2,3,4-butanetetrol) is a four-carbon sugar alcohol with sweetening properties that is used by the agrofood industry as a food additive. In this study, we demonstrated that metabolic engineering can be used to improve the production of erythritol from glycerol in the yeast Yarrowia lipolytica. The best results were obtained using a mutant that overexpressed GUT1 and TKL1, which encode a glycerol kinase and a transketolase, respectively, and in which EYK1, which encodes erythrulose kinase, was disrupted; the latter enzyme is involved in an early step of erythritol catabolism. In this strain, erythritol productivity was 75% higher than in the wild type; furthermore, the culturing time needed to achieve maximum concentration was reduced by 40%. An additional advantage is that the strain was unable to consume the erythritol it had created, further increasing the process's efficiency. The erythritol productivity values we obtained here are among the highest reported thus far. [less ▲]

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See detailEnhancing the sweetener erythritol productivity in Yarrowia lipolytica using metabolic engineering
Carly, Frédéric; Vandermies, Marie ULiege; Nicaud, Jean-Marc et al

Conference (2017, June)

Erythritol (1,2,3,4-butanetetrol) is a four-carbon sugar alcohol used as sweeteners in food and beverage industry. It is most commonly generated from glucose via fermentation using osmophilic yeasts ... [more ▼]

Erythritol (1,2,3,4-butanetetrol) is a four-carbon sugar alcohol used as sweeteners in food and beverage industry. It is most commonly generated from glucose via fermentation using osmophilic yeasts. Yarrowia lipolytica is highly proficient at producing erythritol and can use raw glycerol instead of glucose as its main carbon source. Raw glycerol is a byproduct of the biodiesel industry, and it is a cheaper and more efficient carbon source than glucose when it comes to producing erythritol. To date, most studies seeking to improve erythritol production have used wild type strains or randomly generated mutants and have focused on optimizing the culture medium or culturing conditions. In this study, we demonstrated that metabolic engineering can be used to enhance the production of erythritol from glycerol. To this end, we constructed a set of eleven strains that overexpressed genes encoding key enzymes of either glycerol catabolism and erythritol synthesis pathway. For the best of our engineered strains, erythritol productivity in bioreactor was increased 78% relative to the wild type strain and maximum concentrations were obtained in 40% less time. [less ▲]

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See detailAn anticancer molecule stemming from a plant root produced in a bioreactor
Vassaux, Antoine; Tarayre, Cédric ULiege; Delvigne, Frank ULiege et al

Poster (2017, May 24)

Secondary metabolites produced by plants or their symbionts have already shown specific properties: anticancer, anti-inflammatory, antibacterial, antifungal effects, etc. Astin C is a non-ribosomal ... [more ▼]

Secondary metabolites produced by plants or their symbionts have already shown specific properties: anticancer, anti-inflammatory, antibacterial, antifungal effects, etc. Astin C is a non-ribosomal peptide (secondary metabolite) produced by the fungus Villosirosea asteris, endosymbiont of the medicinal plant Aster tataricus, which has shown an interesting anticancer activity. The current challenge is the production of the molecule on a large scale and in higher quantities, either from the original fungus through fermentation technologies, or by a heterologous yeast strain having integrated the genes involved in the astin C biosynthesis pathway. The purpose of this workshop is to highlight the implementation possibilities of a strain producing a metabolite of interest. [less ▲]

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See detailNew inducible promoter for gene expression and synthetic biology in Yarrowia lipolytica
Trassaert, Marion; Vandermies, Marie ULiege; Carly, Frédéric et al

in Microbial Cell Factories (2017), 16(141),

Background The oleaginous yeast Yarrowia lipolytica is increasingly used as alternative cell factory for the production of recombinant proteins. At present, several promoters with different strengths have ... [more ▼]

Background The oleaginous yeast Yarrowia lipolytica is increasingly used as alternative cell factory for the production of recombinant proteins. At present, several promoters with different strengths have been developed based either on the constitutive pTEF promoter or on oleic acid inducible promoters such as pPOX2 and pLIP2. Although these promoters are highly efficient, there is still a lack of versatile inducible promoters for gene expression in Y. lipolytica. Results We have isolated and characterized the promoter of the EYK1 gene coding for an erythrulose kinase. pEYK1 induction was found to be impaired in media supplemented with glucose and glycerol, while the presence of erythritol and erythrulose strongly increased the promoter induction level. Promoter characterization and mutagenesis allowed the identification of the upstream activating sequence UAS1EYK1. New hybrid promoters containing tandem repeats of either UAS1XPR2 or UAS1EYK1 were developed showing higher expression levels than the native pEYK1 promoter. Furthermore, promoter strength was improved in a strain carrying a deletion in the EYK1 gene, allowing thus the utilization of erythritol and erythrulose as free inducer. Conclusions Novel tunable and regulated promoters with applications in the field of heterologous protein production, metabolic engineering, and synthetic biology have been developed, thus filling the gap of the absence of versatile inducible promoter in the yeast Y. lipolytica. [less ▲]

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See detailIdentification and characterization of EYK1, a key gene for erythritol catabolism in Yarrowia lipolytica
Carly, Frédéric; Gamboa-Melendez, Heber; Vandermies, Marie ULiege et al

in Applied Microbiology and Biotechnology (2017), 101

Erythritol is a four-carbon sugar alcohol synthesized by osmophilic yeasts, such as Yarrowia lipolytica, in response to osmotic stress. This metabolite has application as food additive due to its ... [more ▼]

Erythritol is a four-carbon sugar alcohol synthesized by osmophilic yeasts, such as Yarrowia lipolytica, in response to osmotic stress. This metabolite has application as food additive due to its sweetening properties. Although Y. lipolytica can produce erythritol at a high level from glycerol, it is also able to consume it as carbon source. This ability negatively affects erythritol productivity and represents a serious drawback for the development of an efficient erythritol production process. In this study, we have isolated by insertion mutagenesis a Y. lipolytica mutant unable to grow on erythritol. Genomic characterization of the latter highlighted that the mutant phenotype is directly related to the disruption of the YALI0F01606g gene. Several experimental evidences suggested that the identified gene, renamed EYK1, encodes an erythrulose kinase. The mutant strain showed an enhanced capacity to produce erythritol as compared to the wild-type strain. Moreover, in specific experimental conditions, it is also able to convert erythritol to erythrulose, another compound of biotechnological interest. [less ▲]

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See detailDeciphering how LIP2 and POX2 promoters can optimally regulate recombinant protein production in the yeast Yarrowia lipolytica.
Sassi, Hosni; Delvigne, Frank ULiege; Nicaud, Jean-Marc et al

in Microbial Cell Factories (2016), 15(1), 159

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See detailInfluence of methanol/sorbitol co-feeding rate on pAOX1 induction in a Pichia pastoris Mut+ strain in bioreactor with limited oxygen transfer rate.
Carly, F.; Niu, H.; Delvigne, Frank ULiege et al

in Journal of industrial microbiology & biotechnology (2016), 43(4), 517-23

High Pichia pastoris biomass density could be obtained using high co-feeding rate of methanol and sorbitol in a fed-batch or continuous culture, while further higher feeding rate finally leads to oxygen ... [more ▼]

High Pichia pastoris biomass density could be obtained using high co-feeding rate of methanol and sorbitol in a fed-batch or continuous culture, while further higher feeding rate finally leads to oxygen limitation in bioreactor. In the literature, there is lack of report about AOX1 promoter regulation with regard to dissolved oxygen level (DO). Therefore, in this work, chemostat cultures were performed to investigate the cell growth, metabolism and regulation of the AOX1 promoter (pAOX1) regarding co-feeding rate of optimized methanol/sorbitol mixture (methanol fraction 0.60 C-mol/C-mol) using a P. pastoris Mut+/pAOX1-lacZ strain. The oxygen transfer rates (OTR) in bioreactor were kept in the range of typical values of large bioreactor, i.e., 4-8 g/(L h) if DO equals 30 % saturation or 5-10 g/(L h) if DO nears zero. For DO >0, an increase of the carbon fed led to an increase of pAOX1 induction. By contrast, when dissolved oxygen was completely depleted, methanol accumulated, causing a 30 % decrease of pAOX1 induction. However, this decrease is more likely to be lined to methanol accumulation than to low level of dissolved oxygen (<4 % DO). Methanol/sorbitol co-feeding allowed cells to adapt to oxygen transient limitations that often occur at industrial scale with reduced effect on pAOX1 induction. The optimal feeding rate tested here was 6.6 mmol C (DCW h)(-1) at an OTR of 8.28 g O2(L h)(-1) with over fivefold pAOX1 induction (probably directly associated with target protein productivity) compared with previous work. [less ▲]

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See detailOpportunités pour la valorisation des végétaux riches en anthocyanes comme sources de colorants alimentaires (synthèse bibliographique)
Beye, Cheikh ULiege; Tounkara, Lat Souk; Seck, Mamadou Amadou et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(4), 392-401

Introduction. Très répandues dans le règne végétal, les anthocyanes sont le sujet d’un grand nombre d’études qui abordent en général les aspects concernant leur instabilité vis-à-vis des conditions dans ... [more ▼]

Introduction. Très répandues dans le règne végétal, les anthocyanes sont le sujet d’un grand nombre d’études qui abordent en général les aspects concernant leur instabilité vis-à-vis des conditions dans lesquelles elles sont employées ou l’effet bénéfique de leur consommation sur la santé. Littérature. Ces aspects sont particulièrement importants lorsqu’on envisage de les extraire en vue de leur utilisation comme colorant alimentaire naturel. Dans cette revue bibliographique, les propriétés des anthocyanes susceptibles d’être altérées lors de leur transformation ont été étudiées. Par la suite, un état des lieux sur les méthodes de fabrication de colorants à base d’anthocyanes a été fait afin de dégager des perspectives pour l’exploitation des matières végétales qui en contiennent de grandes quantités. Conclusions. Les fruits et légumes utilisables pour la fabrication de colorants alimentaires sont nombreux et variés. Les différences au niveau du contenu ont une influence sur la stabilité de la couleur des extraits, mais les progrès récents en matière de formulation ouvrent des perspectives pour la valorisation des végétaux riches en anthocyanes. [less ▲]

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See detailPhenotypic variability in bioprocessing conditions can be tracked on the basis of on-line flow cytometry and fits to a scaling law
Baert, Jonathan ULiege; Kinet, Romain ULiege; Brognaux, Alison ULiege et al

in Biotechnology Journal (2015)

Noise in gene and protein expression is a major cause for bioprocess deviation. However, this phenomenon has been only scarcely considered in real bioprocessing conditions. In this work, a scaling-law ... [more ▼]

Noise in gene and protein expression is a major cause for bioprocess deviation. However, this phenomenon has been only scarcely considered in real bioprocessing conditions. In this work, a scaling-law derived from a genome-scale studies based on GFP reporter systems has been calibrated to an on-line flow cytometry device, allowing thus to get an insight at the level of promoter activity and associated noise during a whole microbial culture carried out in bioreactor. We show that most of the GFP reporter systems investigated and thus corresponding genes could be included inside the area covered by the scaling-law. The experimental results suggest that this scaling-law could be used to predict the dynamics of promoter activity, as well as the associated noise, in bioprocessing conditions. The knowledge acquired throughout this work could be used for the design of more robust expression systems. [less ▲]

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See detailFungal lipase production by solid-state fermentation
Ramos-Sanchez, L.B.; Julian-Ricardo, M.C.; Cordova, J. et al

Conference (2014, December)

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See detailBacillus as a source of novel antibiotics
Fickers, Patrick ULiege

Conference (2014, November)

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See detailPropuesta de estrategia para la producción de biocombustibles de biomasa lignocelulósica
Ramos-Sanchez, L.B.; Cujilema-Quitio, M.C.; Leon-Revelo, G. et al

Conference (2014, November)

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See detailOptimization of pAOX1 induction in a methanol/sorbitol co-feeding process in Pichia pastoris
Carly, F.; Niu, H.; Fickers, Patrick ULiege

Conference (2014, October)

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See detailOptimization of pAOX1 induction in a methanol/sorbitol co-feeding process in Pichia pastoris Mut+/pAOX1-lacZ strain
Carly, F.; Niu, H.; Fickers, Patrick ULiege

Conference (2014, September)

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