title: [Construction and functional analysis of the pepB gene disruptant in Aspergillus niger].
abstract: An integration plasmid pMW1-pepB for the pepB gene disruption in Aspergillus was constructed. The plasmid contained the pepB gene upstream (P) 1.4kb and downstream (T) 1.3kb homologous fragments with insertion of the expression unit of the hygromycin resistance gene (hph) between them. P and T DNA fragments were synthesized by PCR from Aspergillus niger chromosomal DNA. The integration plasmid was digested with the Hpa I restriction enzyme, the resultant 4.2kb linear fragment was introduced into the Aspergillus niger strain GICC2773 which expressing the glucoamylase/laccase fusion protein by PEG-mediated transformation. 62 Hygromycin resistance transformants were screened, and from them one strain named pepB29 was identified to be the pepB disruptant by PCR analysis. Data of functional assay of the pepB29 strain indicated that the disruption of the pepB gene secreted reduced acid proteolytic activity, and improved the heterologous protein laccase production.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.forename: Jing-Peng
authors.initials: JP
authors.lastname: Li
authors.forename: Ao-Quan
authors.initials: AQ
authors.lastname: Wang
authors.forename: Guo-Min
authors.initials: GM
authors.lastname: Tang
authors.forename: Hua-Ming
authors.initials: HM
authors.lastname: Wang
mesh_terms: D016282:Aspartic Acid Endopeptidases / Q000235:genetics* / Q000502:physiology; D001234:Aspergillus niger / Q000201:enzymology* / Q000235:genetics; D002934:Cinnamates / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D006921:Hygromycin B / Q000031:analogs & derivatives / Q000494:pharmacology; D042845:Laccase / Q000096:biosynthesis; D010957:Plasmids; D016133:Polymerase Chain Reaction
chemical_list: D002934:Cinnamates; D006921:Hygromycin B; C026273:hygromycin A; D042845:Laccase; D016282:Aspartic Acid Endopeptidases