Secretion of a Cytoplasmic Protein Using Escherichia coli α-Hemolysin Membrane Transport System

Abstract

Several fusion proteins composed of the cytoplasmic protein Escherichia coli dihydrofolate reductase (DHFR) and E. coli α-hemolysin (HlyA) were constructed and their secretion to the medium was examined in order to develop a specific secretion system. Although no chimeric proteins having an intact DHFR region were secreted, those lacking a C-terminal moiety of DHFR were secreted to the culture medium by the hemolysin transport system.
The C-terminal region of HlyA necessary for its secretion was shown to exist at least within the final 61 amino acids stretch according to the results of secretion of the fused proteins.