title: Enhanced production of heterologous proteins by the filamentous fungus Trichoderma reesei via disruption of the alkaline serine protease SPW combined with a pH control strategy.
abstract: The filamentous fungus Trichoderma reesei has received attention as a host for heterologous protein production because of its high secretion capacity and eukaryotic post-translational modifications. However, the heterologous production of proteins in T. reesei is limited by its high expression of proteases. The pH control strategies have been proposed for eliminating acidic, but not alkaline, protease activity. In this study, we verified the expression of a relatively major extracellular alkaline protease (GenBank accession number: EGR49466.1, named spw in this study) from 20 candidates through real-time polymerase chain reaction. The transcriptional level of spw increased about 136 times in response to bovine serum albumin as the sole nitrogen source. Additionally, extracellular protease activity was reduced by deleting the spw gene. Therefore, using this gene expression system, we observed enhanced production and stability of the heterologous alkaline endoglucanase EGV from Humicola insolens using the Δspw strain as compared to the parental strain RUT-C30.
authors.affiliation: State Key Lab of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, China.
authors.forename: Guoxiu
authors.initials: G
authors.lastname: Zhang
authors.affiliation: State Key Lab of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: State Key Lab of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, China.
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Wei
authors.affiliation: State Key Lab of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai, China. Electronic address: wadexp@ecust.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
mesh_terms: D002480:Cellulase / Q000096:biosynthesis / Q000235:genetics; D003001:Cloning, Molecular; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D015966:Gene Expression Regulation, Fungal; D055786:Gene Knockout Techniques; D006863:Hydrogen-Ion Concentration; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D012331:RNA, Fungal / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D057057:Serine Proteases / Q000096:biosynthesis* / Q000235:genetics; D014170:Transformation, Genetic; D014242:Trichoderma / Q000201:enzymology* / Q000235:genetics
chemical_list: D005656:Fungal Proteins; D012331:RNA, Fungal; D002480:Cellulase; D057057:Serine Proteases
keywords: Alkaline endoglucanase; Alkaline serine protease; Trichoderma reesei