Design and Engineering of an Efficient Peroxidase Using Myoglobin for Dye Decolorization and Lignin Bioconversion

International Journal of Molecular Sciences

Xiangshi Tan¹  Shu-Qin Gao²  Ge-Bo Wen²  Jia-Kun Xu³  Ying-Wu Lin⁴  Sheng-Tao Wu⁴  Wen-Jie Guo⁴ 

[1] Department of Chemistry & Institute of Biomedical Science, Fudan University, Shanghai 200433, China;Key Laboratory of Protein Structure and Function of Universities in Hunan Province, University of South China, Hengyang 421001, China;Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Laboratory for Marine Drugs and Byproducts of Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China;School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China;

关键词: heme enzymes;    protein design;    dye-decolorizing peroxidase;    kraft lignin bioconversion;   

DOI  :  10.3390/ijms23010413

来源: DOAJ

【 摘 要 】

The treatment of environmental pollutants such as synthetic dyes and lignin has received much attention, especially for biotechnological treatments using both native and artificial metalloenzymes. In this study, we designed and engineered an efficient peroxidase using the O₂ carrier myoglobin (Mb) as a protein scaffold by four mutations (F43Y/T67R/P88W/F138W), which combines the key structural features of natural peroxidases such as the presence of a conserved His-Arg pair and Tyr/Trp residues close to the heme active center. Kinetic studies revealed that the quadruple mutant exhibits considerably enhanced peroxidase activity, with the catalytic efficiency (k_cat/K_m) comparable to that of the most efficient natural enzyme, horseradish peroxidase (HRP). Moreover, the designed enzyme can effectively decolorize a variety of synthetic organic dyes and catalyze the bioconversion of lignin, such as Kraft lignin and a model compound, guaiacylglycerol-β-guaiacyl ether (GGE). As analyzed by HPLC and ESI-MS, we identified several bioconversion products of GGE, as produced via bond cleavage followed by dimerization or trimerization, which illustrates the mechanism for lignin bioconversion. This study indicates that the designed enzyme could be exploited for the decolorization of textile wastewater contaminated with various dyes, as well as for the bioconversion of lignin to produce more value-added products.

【 授权许可】

Unknown