World free of the devastation of diabetes is not only an admirable vision, but is a vital necessity. The discovery and isolation of insulin in 1921, by Banting and Best, paved the way for the development of a therapy which has saved the life of many diabetic patients. Insulin was the first protein to be sequenced in 1951, marking an important milestone in molecular biology. In 1976, insulin became the first recombinant drug - obtained using newly developed genetic engineering techniques - to be used for therapy in humans . Many proteins such as human insulin cannot be obtained from their natural sources in suitable quantities because of their low abundance or difficulty of purification by conventional methods. One solution is the production of recombinant human proteins in hetero-logous prokaryotic cell systems such as yeast mediated by suitable and powerful expression vectors. Identification of a simple eukaryotic system depend on the expression level, quality of biomolecules, safety, manipulation of genetic system and finally the cost of production