CANDIDA BOIDINII STRAIN HAVING DECREASED PROTEASE ACTIVITY AND ITS USE AS HOST CELL FOR PRODUCTION OF HETEROLOGOUS PROTEIN

摘要

PROBLEM TO BE SOLVED: To obtain the subject new strain consisting of a Candida boidinii strain having decreased protease activity, enabling high expression of heterologous genes, and usable e.g. as host cells capable of producing useful heterologous proteins, such as cathepsin C, in a high yield. SOLUTION: This strain is a new Candida boidinii strain having decreased protease activity (e.g. Candida boidinii SK 741 strain), enables high expression of heterologous genes, and is capable of producing useful heterologous proteins, such as cathepsin C, in high yield. This new strain is obtained by separating chromosomal DNAs from Candida boidinii ATCC 48180 strain, preparing a genomic library by using the chromosomal DNAs, screening the library by a probe to yield a proteinase A gene, elucidating the base sequence of the proteinase A gene, constituting a protease gene-disruptive plasmid, preparing a transformant by using the plasmid to acquire a protease gene-deficient strain.