title: The atmospheric and room-temperature plasma (ARTP) method on the dextranase activity and structure.
abstract: A novel atmospheric and room-temperature plasma (ARTP) method was used to breed high-yielding mutations of Arthrobacter KQ11. Mutagenesis produced two mutations, 4-1 and 4-13, which increased enzyme activity by 19 and 30%, respectively. Dents on the cell envelope were observed under scanning electron microscopy (SEM). The optimal temperature and pH of the wild strain were 45°C and 5.5 and those of the mutant strains were 45°C, pH 6.0 (4-1) and 50°C, pH 6.0 (4-13). Under optimal enzyme production conditions of the wild and mutant strains, the dextranase activity of 4-13 was 50% higher than that of the wild strain. Through amino acid alignment, several nucleotides of the mutant strains were found to have changed. Experiments performed in vitro suggested that this endo-dextranase may inhibit biofilm formation by Streptococcus mutans.
authors.affiliation: Key Laboratory of Marine Biology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China; School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China.
authors.forename: Xiaobei
authors.initials: X
authors.lastname: Wang
authors.affiliation: Jiangsu Marine Resources Development Research Institute, Lianyungang, Jiangsu 222005, China; School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China.
authors.forename: Mingsheng
authors.initials: M
authors.lastname: Lu
authors.affiliation: Jiangsu Marine Resources Development Research Institute, Lianyungang, Jiangsu 222005, China; School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China. Electronic address: shujunwang86@163.com.
authors.forename: Shujun
authors.initials: S
authors.lastname: Wang
authors.affiliation: Jiangsu Marine Resources Development Research Institute, Lianyungang, Jiangsu 222005, China; School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China.
authors.forename: Yaowei
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Key Laboratory of Marine Biology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
authors.forename: Delong
authors.initials: D
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Dalian Ocean University, Dalian, Liaoning 116023, China; School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ren
authors.affiliation: Key Laboratory of Marine Biology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China. Electronic address: seawater@njau.edu.cn.
authors.forename: Gengmao
authors.initials: G
authors.lastname: Zhao
mesh_terms: D001173:Arthrobacter / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018441:Biofilms; D003910:Dextranase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D042822:Genomic Instability; D008958:Models, Molecular; D008970:Molecular Weight; D009154:Mutation; D011487:Protein Conformation; D013329:Structure-Activity Relationship; D013696:Temperature
chemical_list: D003910:Dextranase
keywords: ARTP; Biofilm; Crystal structure; Dextranase; SEM