Brassica rapa hairy root based expression system leads to the production of highly homogenous and reproducible profiles of recombinant human alpha-L-iduronidase

International audienceThe Brassica rapa hairy root based expression platform, a turnip hairy root based expression system, is able to produce human complex glycoproteins such as the alpha—L—iduronidase (IDUA) with an activity similar to the one produced by Chinese Hamster Ovary (CHO) cells. In this article, a particular attention has been paid to the N‐ and O‐glycosylation that characterize the alpha‐L‐iduronidase produced using this hairy root based system. This analysis showed that the recombinant protein is characterized by highly homogeneous post translational profiles enabling a strong batch to batch reproducibility. Indeed, on each of the 6 N‐glycosylation sites of the IDUA, a single N‐glycan composed of a core Man3GlcNAc2 carrying one beta(1,2)‐xylose and one alpha(1,3)‐fucose epitope (M3XFGN2) was identified, highlighting the high homogeneity of the production system. Hydroxylation of proline residues and arabinosylation were identified during O‐glycosylation analysis, still with a remarkable reproducibility. This platform is thus positioned as an effective and consistent expression system for the production of human complex therapeutic proteins

Development of a liquid-liquid extraction method of resveratrol from cell culture media using solubility parameters

YesThe extraction of bioactive compounds, produced by plant cell cultures, directly from their culture medium, which contains other by-products, is a great challenge. Resveratrol extraction from its grapevine cell cultures is considered here as an example to improve the extraction processes from plant cell cultures using solubility parameters. Successive liquid-liquid extraction (LLE) processes were exploited to extract resveratrol from the culture medium with an extraction ratio approaching 100%, high selectivity and minimum amounts of solvents. The calculations of partition coefficients as a function of solubility parameters demonstrated that benzyl benzoate is the most suitable intermediate solvent to extract resveratrol from its aqueous medium. The calculations also illustrated the high ability of methanol and ethanol to extract resveratrol from benzyl benzoate. The physicochemical properties of benzyl benzoate and processing conditions were exploited to separate it from aqueous media and organic solvents. The agitation method, component ratios and extraction time were studied to maximize the extraction yield. Under the best studied conditions, the recovery of resveratrol from different culture media approached ∼100% with a selectivity of ∼92%. Ultimately, the improved extraction processes of resveratrol are markedly efficient, selective, rapid and economical.Mohammad Amin Mohammad gratefully acknowledges CARA (The Council for At-Risk Academics, Stephen Wordsworth and Ryan Mundy) for providing the financial support for an academic fellowship

The Role of Temperature in the Growth and Flowering of Geophytes

Among several naturally occurring environmental factors, temperature is considered to play a predominant role in controlling proper growth and flowering in geophytes. Most of them require a “warm-cold-warm” sequence to complete their annual cycle. The temperature optima for flower meristem induction and the early stages of floral organogenesis vary between nine and 25 °C, followed, in the autumn, by a several-week period of lower temperature (4–9 °C), which enables stem elongation and anthesis. The absence of low temperature treatment leads to slow shoot growth in spring and severe flowering disorders. Numerous studies have shown that the effects of the temperature surrounding the underground organs during the autumn-winter period can lead to important physiological changes in plants, but the mechanism that underlies the relationship between cold treatment and growth is still unclear. In this mini-review, we describe experimental data concerning the temperature requirements for flower initiation and development, shoot elongation, aboveground growth and anthesis in bulbous plants. The physiological processes that occur during autumn-winter periods in bulbs (water status, hormonal balance, respiration, carbohydrate mobilization) and how these changes might provoke disorders in stem elongation and flowering are examined. A model describing the relationship between the cold requirement, auxin and gibberellin interactions and the growth response is proposed

Etude de la biosynthèse et de la production d'alcaloïdes tropaniques par les racines transgéniques de Datura

La croissance et la production en métabolites de deux clones de racines transgéniques de Datura ont été caractérisées en fioles. L'ajout combiné de l'acide (RS)-phényllactique et du Tween a permis d'amplifier la diffusion de l'hyoscyamine dans le milieu de culture et d'augmenter l'accumulation totale de l'hyoscyamine de 60%. La vitesse apparente de biosynthèse de l'hyoscyamine est deux fois inférieure à celle de la littorine suggérant que la réaction d'isomérisation pourrait être une étape limitante dans la voie de biosynthèse. La croissance et la respiration des racines transgéniques ont été déterminés en bioréacteur en utilisant un système d'acquisition en ligne des mesures de conductivité du milieu de culture, de l'oxygène et du dioxyde de carbone. Ces études ont permis de mettre en évidence qu'un rythme circadien endogène persiste chez les racines transformées de D. innoxia. Enfin, un procédé de production semi-continue de scopolamine dans un bioréacteur de 16 litres a été testé.AMIENS-BU Sciences (800212103) / SudocSudocFranceF

Études des mécanismes de croissance des racines Datura innoxia (application à la culture en bioréacteur avec divers modes de conduite)

COMPIEGNE-BU (601592101) / SudocSudocFranceF

Colocalisation de gènes candidats positionnels avec des QTL de la tolérance au gel chez Medicago truncatula

COMPIEGNE-BU (601592101) / SudocSudocFranceF

Conduite de réacteurs biologiques multivariables à comportement complexe (application à un organisme végétal)

COMPIEGNE-BU (601592101) / SudocSudocFranceF

Approches des facteurs de la croissance et du développement de Salicornia Ramosissima Woods en conditions naturelles et contrôlées

En vue d une domestication, Salicornia ramosissima poussant spontanément et déjà grandement récoltée en Baie de Somme, à fait l objet d études présentées dans cette thèse. Après une revue bibliographique permettant de préciser les connaissances déjà acquises sur les salicornes en général et Salicornia ramosissima en particulier, la partie expérimentale porte essentiellement sur l étude des facteurs abiotiques agissant sur la floraison, la maturation et la dormance des graines, ainsi que sur la germination. Il en est de même pour les phénomènes de croissance et de développement. Les travaux ont été complétés quand il était nécessaire par des études anatomiques ou cytologiques, voire métaboliques. Les résultats obtenus permettent d envisager favorablement un transfert de technologie pour cette plante.In the Bay of Somme, Salicornia ramosissima grows up spontaneously and already is largely collected. The species is the subject of the studies presented in this thesis. The first part (bibliography) describes the knowledges published on the salicornes and Salicornia ramosissima. After, are presented the abiotic factors acting on the flowering, the maturation and the dormancy of seeds, like on germination. It is the same for the phenomena of growth and development. Experiments are supplemented when it is necessary by anatomical, or cytological even metabolic studies. The results prepare a technology transfer for this plant.AMIENS-BU Sciences (800212103) / SudocSudocFranceF

Enhanced production of recombinant human gastric lipase in turnip hairy roots

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