SUMO Fusions to Enhance Protein Expression & Secretion

描述(申请人提供)：随着越来越多的蛋白质从基因组测序项目中被识别出来，对于具有学术和临床重要性的蛋白质的表达和纯化来说，对可靠和经济高效的手段的需求越来越大。Lifesensors开发了一种新的相扑融合系统，以增强多种蛋白质在大肠杆菌中的表达和溶解性，并通过附着在相扑上的亲和标签促进蛋白质的下游纯化。该系统的一个重要特征是从表达的蛋白质中切割相扑融合的蛋白酶。去除融合不会留下N-末端的突出部分，因此任何所需的氨基酸都可以在表达蛋白质的N-末端克隆。一些研究或治疗重要的蛋白质在细菌中不能很好地表达或分泌效率不高。我们建议利用相扑的伴随特性来增强蛋白质在大肠杆菌中的表达和分泌。为了扩大相扑融合技术的应用范围，将在相扑N端引入分泌信号。枯草芽孢杆菌和乳酸乳球菌具有广泛的分泌性，在食品工业中有着广泛的应用，但在生物制药工业中还没有被利用来分泌蛋白质。Lifesensors提出了SUMO基因融合系统在枯草芽孢杆菌和乳酸乳球菌中增强模式蛋白表达和分泌的有效性。

DESCRIPTION (provided by applicant): As more proteins are identified from the genome-sequencing projects, there is an increasing need for reliable and cost efficient means for expression and purification of proteins of academic and clinical importance. LifeSensors has developed a novel SUMO-fusion system to enhance expression, and solubility of a wide variety of proteins in E. coli, and to facilitate the downstream purification of the protein via an affinity tag attached to SUMO. An important feature of the system is the protease that cleaves the SUMO-fusion from expressed proteins. Removal of the fusion leaves no N-terminal overhang so that any desired amino acid can be cloned at the N-terminus of the expressed protein. Several research or therapeutically important proteins do not express well in bacteria or inefficiently secreted. We propose to exploit the chaperoning properties of SUMO to enhance expression and secretion of proteins in E coli. To extend the utility of the SUMO-fusion technology, a secretion signal will be introduced at N-terminal of SUMO. Bacillus subtilis and Lactococcus lactis, are well known for their secretory properties and widely used in food industry and yet these bacteria have not been exploited for protein secretion in biopharmaceutical industry. LifeSensors proposes the usefulness of SUMO-gene fusion system to enhance expression and secretion of model proteins in Bacillus subtilis and Lactococcus lactis.