A catalase-peroxidase from a newly isolated thermoalkaliphilic Bacillus sp. with potential for the treatment of textile bleaching effluents

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• 作者：Marinka Gudelj ; Gilbert Fruhwirth ; Andreas Paar ; Fritz Lottspeich ; Karl-Heinz Robra ; Artut Cavaco-Paulo and Georg Gübitz
• 刊名：Extremophiles
• 出版年：2001
• 出版时间：December 2001
• 年：2001
• 卷：5
• 期：6
• 页码：423-429
• 全文大小：139 KB
• 刊物类别：Biomedical and Life Sciences
• 刊物主题：Life Sciences
  Microbiology
  Biotechnology
  Ecology
  
• 出版者：Springer Japan
• ISSN：1433-4909

文摘

A new thermoalkaliphilic bacterium was isolated from a textile wastewater drain and identified as a new Bacillus sp. (Bacillus SF). Because of its high pH stability and thermostability, a catalase-peroxidase (CP) from this strain has potential for the treatment of textile bleaching effluents. The CP from Bacillus SF was purified to more than 70.3-fold homogeneity using fractionated ammonium sulfate precipitation, hydrophobic interaction, and anion-exchange and gel-filtration chromatography. The native CP had a molecular mass of 165 kDa and was composed of two identical subunits. The isoelectric point of the protein was at pH 6.0. Peptide mass mapping using matrix-assisted laser desorption ionization-mass spectrometry showed a homology between the CP from Bacillus SF and the CP from Bacillus stearothermophilus. The apparent Km value of the catalase activity for H2O2 was 2.6 mM and the kcat value was 11,475 s-1. The enzyme showed high catalase activity and an appreciable peroxidase activity with guaiacol and o-dianisidine. The enzyme was stable at high pH, with a half-life of 104 h at pH 10 and 25°C and 14 h at 50°C. The enzyme was inhibited by azide and cyanide, in a competitive manner, but not by the catalase-specific inhibitor 3-amino-1,2,4-triazole.