Fungal Biotechnology: Expressiion and Secretion of Heterologous Proteins in Aspergillus oryzae

摘要

Aspergillus oryzae is an important microorganism for the production of industrial enzymes nad for fermented food products. its ability to sectete these proteins is appealing for the production of heterologous proteins in the field of the genetic engineering. For the development of transformation system in A.oryzae, arg B-mutants were isolated by using UV irradiation. Transformation was achieved with the plasmids which carries the A.nidulans argB gene by usign CaCl sub 2-mediated chemical method an electroporation. The transformed plasmids were integratedinto the host chromosome with multiple copies an stable transformants obtained. The frequency fo transofrmation was, however, low between 10 to 50 transformants per mivg A.oryzae argB gene, it complements the A.oryzae argB mutant. In electric field-mediated trans-formation, electroporation, the optimum conditions for A.oryzae was obtained at 6.3kV/cm and 1540 ohm. The survivals of protoplasts in the electric fields were about 80