Abstract: A recombinant microorganism having improved productivity for a protein or a polypeptide, and a method for producing a protein or a polypeptide using the recombinant microorganism, are provided. A recombinant microorganism obtained by transfecting a gene for encoding a desired protein or polypeptide into a microorganism strain which is obtained by genetically constructing to overexpress secY gene of Bacillus subtilis or a gene corresponding to the secY gene, and deleting or inactivating one or more genes selected from sporulation-associated genes and genes corresponding to the sporulation-associated genes from the genome.

Abstract: The object of the invention is to provide a microorganism which enhances productivity of cellulase and is useful for industrial production of cellulase, and to provide a method for producing cellulase by use of the microorganism. The present invention provides a recombinant microorganism produced by transferring a gene encoding cellulase to a parental microorganism which has been genetically modified so as to overexpress a Bacillus subtilis secY gene or a gene corresponding thereto.