The effects of phage defense on recombinant protein expression

为了产生大量用于生物技术应用的蛋白质，通常需要在不同于原始来源的生物体中将蛋白质表达为“重组”产物(例如，在细菌细胞中产生人类蛋白质)。这是必要的，因为通常很难从天然来源获得足够量的蛋白质。在实际应用中，细菌系统是理想的，因为细菌生长迅速，细菌生长介质便宜，细菌生理相对较好，而且已经开发出几种转基因细菌，可以生产高质量、完整的重组蛋白。尽管在细菌系统中生产蛋白质的技术已经发展，但由于未知的原因，仍然很难获得某些蛋白质的高产量。当试图从人类等高等生物中生产蛋白质时，这一点尤其正确，因为与细菌相比，人类的基因结构存在微小但显著的差异。2000年，30种领先的重组蛋白的销售额超过130亿美元，其中56亿美元是在大肠杆菌中生产的。使重组蛋白更容易表达或提高产量的进展将引起许多重要行业的极大兴趣。

To generate large quantities of proteins used for biotechnology applications, it is usually necessary to express the protein as a "recombinant" product in an organism distinct from the original source (e.g. producing a human protein in a bacterial cell). This is necessary because it is generally difficult to obtain adequate quantities of protein from native sources. When practical, bacterial systems are ideal because bacteria grow rapidly, bacterial growth medium is inexpensive, bacterial physiology is relatively well understood, and several strains of genetically modified bacteria have been developed that can produce high-quality, intact recombinant proteins. Despite the development of techniques for protein production in bacterial systems, it is still difficult to obtain high-yields of certain proteins for unknown reasons. This is particularly true when attempting the production of proteins from higher organisms such as humans, due to the small but significant differences in human gene structure compared to bacteria. In 2000 the sales of the 30 leading recombinant proteins exceeded $13 billion, $5.6 billion of which were produced in E. coli. Advances that make it easier to express or increase yield of recombinant proteins would be of considerable interest to a large number of important industries.