LARGE-SCALE PRODUCTION & PURIFICATION OF COMPOUNDS WITH BIOLOGICAL ACTIVITY

生物技术股负责生物材料的生产和提纯。该股承担广泛的生物生产任务，例如大规模培养原核生物和真核生物，以及生产和提纯生物化合物，特别是蛋白质。这些产品无法从商业渠道获得，但需要用于临床和结构研究。生物技术股有能力通过实施生理和技术方法来处理这些不同的生产任务。由于该股拥有两个综合要素：全面运作的多用途试生产设施和进行研究和工艺开发的能力，因此有可能进行有效的工艺开发和生产。在过去的一年里，该单位进行了大约200种不同的大规模准备工作，包括：1)培养各种微生物，如重组大肠杆菌、重组酿酒酵母、重组毕赤酵母、白喉棒状杆菌突变株、多种沙门氏菌和志贺氏菌以及炭疽杆菌突变株；2)大量繁殖各种哺乳动物细胞，如HeLa、HEK 293和CHO；3)纯化制备结合疫苗所需的克克白喉毒素CRM和重组铜绿假单胞菌外毒素A；4)用填充床生物反应器从重组HEK 293细胞生产人甲状旁腺样钙受体胞外区。在研发领域，该单位继续开展以下主题的工作：1)开发更有效的大规模蛋白质回收方法，在此，我们实施了利用扩展床吸附技术捕获蛋白质的实验，包括洋葱交换器、螯合树脂和疏水树脂；2)利用核磁共振和质谱仪方法，了解不同重组大肠杆菌菌株的葡萄糖代谢，以找出为什么某些菌株更适合外来蛋白质生产；3)建立用于生产重组蛋白质的果蝇细胞培养发酵工艺；以及4)改进毕赤酵母重组蛋白的生产工艺，尤其是内皮抑素和血管抑素。此外，该单位还启动了两个主题的研究工作，一个是重组大肠杆菌各种高密度生长策略对重组蛋白生产的影响，另一个是从HeLa/Vacinia系统生产重组蛋白的过程。该股与LDMI、NICHD合作，开展了针对伤寒沙门氏菌的新疫苗的开发工作。该产品目前正处于现场试验阶段。

The Biotechnology Unit is responsible for the production and purification of biological material. The Unit undertakes a wide array of biological production tasks such as large-scale growth of prokaryotes and eucaryotes, and production and purification of biological compounds especially proteins. These products, not available from commercial sources, are needed for clinical and structural studies. The Biotechnology Unit is capable of handling these various production tasks by implementing both physiological and technical approaches. Efficient process development and production is possible since the Unit possesses two integrated elements: a fully operational multi-purpose pilot production facility and the capability of conducting research and process development. During the last year the unit performed approximately 200 different, large scale preparations including: 1) growing various microorganisms such as recombinant Escherichia coli, recombinant Saccharomyces cerevisiae, recombinant Pichia pastoris, mutant strains of Corynebacteria diphtheria, several types of Salmonella and Shigella and mutant strain of Bacillus anthracis; 2) propagating large volumes of various mammalian cells such as HeLa, HEK 293 and CHO; 3) purifying gram quantities of diphtheria toxin CRM (Cross Reacting Material) and recombinant Pseudomonas aeruginosa exotoxin A needed for the preparation of conjugated vaccines; and 4) producing the extracellular domain of the human parathyroid Ca++ receptor from recombinant HEK 293 cells using a packed bed bioreactor. In the research and development arena, the unit continues its work in the following topics:1) development of more efficient methods for large scale protein recovery, here we performed experiments implementing expanded bed adsorption techniques for capturing proteins onion exchangers, chelating and hydrophobic resins; 2) conducting research aimed at understanding the glucose metabolism of various recombinant E. coli strains in an effort to find out why certain strains are more suitable for foreign protein production, using NMR and Mass Spectrophotometer methods; 3) developing fermentation procedures for growing Drosophila cells for the production of recombinant proteins; and 4) conducting experiments for improving the production protocol of recombinant proteins from Pichia pastoris, especially endostatin and angiostatin. In addition, the unit initiate research work in two topics, one is on the effect of various high density growth strategies of recombinant E. coli, on the production of recombinant proteins, and the other is on the production process of recombinant proteins from the HeLa/vaccinia system. In collaboration with LDMI, NICHD, the unit conducted work on the development of new vaccine against Salmonella typhi. The product is currently in field trial.