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The technology for the production of recombinant proteins has been recognized as an essential field not only for the biopharmaceuticals but also for the functional genomics. In vast quantities of genomic information, numerous uncovered proteins with values for human drugs and industrial enzymes are waiting for their characterizations and proper applications. Unfortunately, however, about 20-30% of tested proteins could be produced under the current expression systems. Thus, post-genomic biology requires novel expression strategies and improved throughput for the breakthrough of the current limitations. A GRAS yeast Saccharomyces cerevisiae has an excellent protein secretion pathway and post-translational modification function necessary for higher eukaryotic proteins. During the last two decades, S. cerevisiae has been frequently chosen for the secretory production of numerous proteins. But the yield of target proteins was generally low and unpredictable. In fact, there has been limited number of vectors available with secretion signals from several known proteins, such as mating factor alpha, invertase, and acid
phosphatase etc. Such could not completely support the secretion of numerous target proteins having different physicochemical properties. For the improvement of the yeast secretion systems, more signals from different types of secretory protein and screening methods of an optimal signal from the pool of secretion signals for each target protein, are required. There are about 600 yeast ORFs among 6,000 encoding secretory proteins which pass the ER and having different secretion signals. To utilize them all for the secretion of numerous target proteins, genome-wide TFP (translational fusion partner) library containing different signal sequences have been constructed. Simple insertion of target gene into TFP library vectors and a positive selection on media could find an optimal fusion partner in a high throughput manner. The technology could rapidly screen a TFP capable of inducing hyper-secretion of target proteins, especially proteins that are difficult to produce using conventional recombinant production ethods. The platform technology will be useful for the production of massive recombinant proteins of bio-industry and basic research in the post-genome era. Several industrial applications of recombinant proteins produced up to grams per liter, especially for bioenergy field will be presented.