ABSTRACT
To avoid the renaturation procedure and develop a more efficient method for the isolation of active tuna growth hormone (tGH), the expression of tGH cDNA in in S. cerevisiae was investigated. The cDNAs coding for eukaryotic proteins are generally cloned in bacterial expression vectors under the control of the lac or the tac promoter and the Shine-Dalgarno sequence to produce the proteins in E coli. A gene for a light-harvesting chlorophyll a/b-binding protein from pea (Pisum sativum L.) has been cloned in a bacterial expression vector. Self-cloning of the xylanase gene in Streptomyces lividans resulted in six-fold overproduction of the enzyme. Continued efforts in the application of recombinant DNA to fermentations have led to overproduction of limiting enzymes of important biosynthetic pathways, thereby increasing production of the final products. Substantial overproduction of daunorubicin was achieved by cloning of DNA fragments encoding daunorubicin biosynthetic genes into producing cultures of Streptomyces peucetius, S. peucetius subsp. caesius, and a blocked mutant.
