A synthetic operon containing 14 bovine pancreatic trypsin inhibitor genes is expressed in E. coli.

The EMBO journal

PubMedID: 2434325

von Wilcken-Bergmann B, Tils D, Sartorius J, Auerswald EA, Schröder W, Müller-Hill B. A synthetic operon containing 14 bovine pancreatic trypsin inhibitor genes is expressed in E. coli. EMBO J. 1986;5(12):3219-25.
A synthetic gene encoding the protein sequence of mature bovine pancreatic trypsin inhibitor (BPTI) has been cloned into a novel E. coli expression vector. After in vitro gene amplification by successive DNA duplications, more than 600 000 mostly inactive inhibitor molecules may be recovered from a single cell. After purification the inhibitory activity can be reconstituted almost completely. The specificity of BPTI for trypsin is abolished by a single amino acid exchange from lysine to isoleucine at position 15. The altered protein is shown to be an efficient inhibitor of human leukocyte elastase.