title: Recombinant expression and characterization of an acid-, alkali- and salt-tolerant β-1,3-1,4-glucanase from Paenibacillus sp. S09.
abstract: A new β-1,3-1,4-glucanase gene (PlicA) was cloned from Paenibacillus sp. S09. The ORF contained 717 bp coding for a 238 amino acid protein. PlicA, expressed in Escherichia coli and purified by Ni(2+)-affinity chromatography, had optimum activity at 55 °C and pH 6.2. The specific activity toward barley β-glucan reached 7,055 U/mg. K m and V max values with barley β-glucan were 3.7 mg/ml and 3.3 × 10(3) μmol/min mg, respectively. The enzyme exhibited acid- and alkali-tolerance with more than 80 % activity remaining after incubation for 4 h at pH 3.5-12. PlicA was salt-tolerant (>90 % activity retained in 4 M NaCl at 25 °C for 24 h) and salt-activated: activity rising 1.5-fold in 0.5 M NaCl. The thermostability was improved by NaCl and CaCl2. This is the first report of an acid-, alkali- and salt-tolerant bacterial β-1,3-1,4-glucanase with high catalytic efficiency.
authors: Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China, chengrui.1988@163.com.
authors: Rui
authors: R
authors: Cheng
authors: Linxiang
authors: L
authors: Xu
authors: Shiming
authors: S
authors: Wang
authors: Yang
authors: Y
authors: Wang
authors: Jianfa
authors: J
authors: Zhang
mesh_terms: D000143:Acids / Q000378:metabolism; D000468:Alkalies / Q000378:metabolism; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D044644:Endo-1,3(4)-beta-Glucanase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism*; D004795:Enzyme Stability; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D056507:Paenibacillus / Q000201:enzymology* / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D012492:Salts / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013696:Temperature; D047071:beta-Glucans / Q000378:metabolism
chemical_list: D000143:Acids; D000468:Alkalies; D004269:DNA, Bacterial; D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D012492:Salts; D047071:beta-Glucans; D044644:Endo-1,3(4)-beta-Glucanase