title: Comparative genomic analysis identified a mutation related to enhanced heterologous protein production in the filamentous fungus Aspergillus oryzae.
abstract: Genomic mapping of mutations using next-generation sequencing technologies has facilitated the identification of genes contributing to fundamental biological processes, including human diseases. However, few studies have used this approach to identify mutations contributing to heterologous protein production in industrial strains of filamentous fungi, such as Aspergillus oryzae. In a screening of A. oryzae strains that hyper-produce human lysozyme (HLY), we previously isolated an AUT1 mutant that showed higher production of various heterologous proteins; however, the underlying factors contributing to the increased heterologous protein production remained unclear. Here, using a comparative genomic approach performed with whole-genome sequences, we attempted to identify the genes responsible for the high-level production of heterologous proteins in the AUT1 mutant. The comparative sequence analysis led to the detection of a gene (AO090120000003), designated autA, which was predicted to encode an unknown cytoplasmic protein containing an alpha/beta-hydrolase fold domain. Mutation or deletion of autA was associated with higher production levels of HLY. Specifically, the HLY yields of the autA mutant and deletion strains were twofold higher than that of the control strain during the early stages of cultivation. Taken together, these results indicate that combining classical mutagenesis approaches with comparative genomic analysis facilitates the identification of novel genes involved in heterologous protein production in filamentous fungi.
authors.affiliation: Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, 159 Longpan Road, Nanjing, 210037, China.|Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Feng-Jie
authors.identifier: http://orcid.org/0000-0003-0376-0964
authors.initials: FJ
authors.lastname: Jin
authors.affiliation: Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Katayama
authors.affiliation: Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan. amarujun@mail.ecc.u-tokyo.ac.jp.
authors.forename: Jun-Ichi
authors.initials: JI
authors.lastname: Maruyama
authors.affiliation: Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kitamoto
mesh_terms: D001236:Aspergillus oryzae / Q000235:genetics* / Q000378:metabolism*; D004252:DNA Mutational Analysis; D005658:Fungi / Q000235:genetics* / Q000378:metabolism*; D017353:Gene Deletion; D016681:Genome, Fungal; D023281:Genomics; D059014:High-Throughput Nucleotide Sequencing; D009113:Muramidase / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D009113:Muramidase
keywords: Aspergillus oryzae; Comparative genomic analysis; Heterologous protein production; Lysozyme; Mutant