title: Genome shuffling of Penicillium citrinum for enhanced production of nuclease P1.
abstract: Genome shuffling is a powerful approach for efficiently engineering industrial microbial strains with interested phenotypes. Here we reported a high producer of nuclease P1, Penicillium citrinum G-16, that was bred by the classical physics-mutagenesis and genome shuffling process. The starting populations were generated by (60)Co γ-irradiation mutagenesis. The derived two protoplast fractions were inactivated by heat-treatment and ultraviolet radiation respectively, then mixed together and subjected to recursive protoplast fusion. Three recombinants, E-16, F-71, and G-16, were roughly obtained from six cycles of genome shuffling. The activity of nuclease P1 by recombinant G-16 was improved up to 1,980.22 U4/ml in a 5-l fermentor, which was 4.7-fold higher than that of the starting strain. The sporulation of recombinant G-16 was distinguished from the starting strain. Random amplified polymorphic DNA assay revealed genotypic differences between the shuffled strains and the wild type strain. The close similarity among the high producers suggested that the genetic basis of high-yield strains was achieved by genome shuffling.
authors.affiliation: Department of Biological Engineering, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310025, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Gongzhen
authors.initials: G
authors.lastname: Wu
authors.forename: Yudong
authors.initials: Y
authors.lastname: Li
authors.forename: Yinyin
authors.initials: Y
authors.lastname: Huang
authors.forename: Fuming
authors.initials: F
authors.lastname: Zhang
authors.forename: Xinle
authors.initials: X
authors.lastname: Liang
mesh_terms: D032621:DNA Shuffling / Q000379:methods*; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000302:isolation & purification; D024861:Genetic Enhancement / Q000379:methods*; D016681:Genome, Fungal / Q000235:genetics*; D016296:Mutagenesis / Q000235:genetics*; D010407:Penicillium / Q000502:physiology*; D015719:Single-Strand Specific DNA and RNA Endonucleases / Q000096:biosynthesis* / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D005656:Fungal Proteins; C526100:Nuclease P1, Penicillium citrinum; D015719:Single-Strand Specific DNA and RNA Endonucleases