Miguel Sissi, Nisse Estelle, Biteau Flore, Rottloff Sandy, Mignard Benoit, Gontier Eric, Hehn Alain, Bourgaud Frédéric
Plant Advanced Technologies SA, Vandoeuvre-lès-Nancy, France.
Laboratoire Agronomie et Environnement, INRA, Université de Lorraine, Vandoeuvre-lès-Nancy, France.
Front Plant Sci. 2019 Jun 19;10:793. doi: 10.3389/fpls.2019.00793. eCollection 2019.
The recovery of recombinant proteins from plant tissues is an expensive and time-consuming process involving plant harvesting, tissue extraction, and subsequent protein purification. The downstream process costs can represent up to 80% of the total cost of production. Secretion-based systems of carnivorous plants might help circumvent this problem. and can produce and excrete out of their tissues a digestive fluid containing up to 200 mg. L of natural proteins. Based on the properties of these natural bioreactors, we have evaluated the possibility to use carnivorous plants for the production of recombinant proteins. In this context, we have set up original protocols of stable and transient genetic transformation for both and sp. The two major drawbacks concerning the proteases naturally present in the secretions and a polysaccharidic network composing the glue were overcome by modulating the pH of the plant secretions. At alkaline pH, digestive enzymes are inactive and the interactions between the polysaccharidic network and proteins in the case of are subdued allowing the release of the recombinant proteins. For , a concentration of 25 μg of GFP/ml of secretion (2% of the total soluble proteins from the glue) was obtained for stable transformants. For , a concentration of 0.5 ng of GFP/ml secretions (0.5% of total soluble proteins from secretions) was reached, corresponding to 12 ng in one pitcher after 14 days for transiently transformed plants. This plant-based expression system shows the potentiality of biomimetic approaches leading to an original production of recombinant proteins, although the yields obtained here were low and did not allow to qualify these plants for an industrial platform project.
从植物组织中回收重组蛋白是一个昂贵且耗时的过程，涉及植物收获、组织提取以及后续的蛋白纯化。下游加工成本可能占到总生产成本的80%。食虫植物基于分泌的系统可能有助于解决这个问题。它们能够在组织外产生并分泌出一种含有高达200毫克/升天然蛋白的消化液。基于这些天然生物反应器的特性，我们评估了利用食虫植物生产重组蛋白的可能性。在此背景下，我们为[具体植物名称1]和[具体植物名称2]物种建立了稳定和瞬时遗传转化的原始方案。通过调节植物分泌物的pH值，克服了与分泌物中天然存在的蛋白酶以及构成[具体植物名称1]黏液的多糖网络相关的两个主要缺点。在碱性pH条件下，消化酶无活性，并且在[具体植物名称1]的情况下，多糖网络与蛋白质之间的相互作用减弱，从而使重组蛋白得以释放。对于[具体植物名称1]，稳定转化体的分泌物中绿色荧光蛋白（GFP）浓度达到25微克/毫升（占黏液中总可溶性蛋白的2%）。对于[具体植物名称2]，分泌物中GFP浓度达到0.5纳克/毫升（占分泌物中总可溶性蛋白的0.5%），对于瞬时转化的植物，14天后一个捕虫笼中的含量相当于12纳克。这种基于植物的表达系统显示了仿生方法在重组蛋白原始生产方面的潜力，尽管这里获得的产量较低，还不足以使这些植物适用于工业平台项目。
