Enhanced alkaline catalase production by Serratia marcescens FZSF01: Enzyme purification, characterization, and recombinant expression

• Published in: Electronic Journal of Biotechnology Vol. 30; pp. 110 - 117
• Main Authors: Jia, Xianbo, Lin, Xinjian, Lin, Chenqiang, Lin, Lirong, Chen, Jichen
• Format: Journal Article
• Language: English
• Published: Elsevier España, S.L.U 01.11.2017; Elsevier
• Subjects: Alkaline; Catalase; Catalase activity; Catalase assay; Catalase gene; Catalase producing strains; Catalase purification; Fermentation; Hydrogen peroxide; Ultrasonication; Ultrasonication; Catalase purification; Hydrogen peroxide; Catalase; Alkaline; Catalase activity; Catalase gene; Fermentation; Catalase assay; Catalase producing strains
• ISSN: 0717-3458; 0717-3458
• DOI: 10.1016/j.ejbt.2017.10.001

Catalase (CAT) is an important enzyme that degrades H2O2 into H2O and O2. To obtain an efficient catalase, in this study, a new strain of high catalase-producing Serratia marcescens, named FZSF01, was screened and its catalase was purified and characterized. After optimization of fermentation conditions, the yield of catalase produced by this strain was as high as 51,468U/ml. This catalase was further purified using two steps: DEAE-fast flow and Sephedex-G150. The purified catalase showed a specific activity of 197,575U/mg with a molecular mass of 58kDa. This catalase exhibited high activity at 20–70°C and pH5.0–11.0. Km of the catalase was approximately 68mM, and Vmax was 1886.8mol/minmg. This catalase was further identified by LC–MS/MS, and the encoding gene was cloned and expressed in Escherichia coli BL21 (DE3) with a production of 17,267±2037U/ml. To our knowledge, these results represent one of the highest fermentation levels reported among current catalase-producing strains. This FZSF01 catalase may be suitable for several industrial applications that comprise exposure to alkaline conditions and under a wide range of temperatures.