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

Abstract

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 (kcat/Km) 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.

De Novo Assembly of a Sarcocarp Transcriptome Set Identifies AaMYB1 as a Regulator of Anthocyanin Biosynthesis in Actinidia arguta var. purpurea

“…AaMYB308 was significantly correlated with Beta-glucosidase (BGL) and Peroxidase (PER) genes, while also correlated with other MYB transcription factor genes, such as AaMYB1 ( Figure 5 G). However, BGL and PER were reported to be key enzymes in the lignin metabolic pathway of phenylpropanoid biosynthesis [ 43 , 44 ]. AaMYB4 and AaMYB35 have close homology to AtMYB4 and AtMYB35 , and AtMYB35 was reported to be involved in tapetum development [ 45 ], AtMYB4 was reported to function as a repressor of cinnamate 4-hydroxylase (C4H) to inhibit lignin biosynthesis [ 46 ].…”

Biodegradation of harmful industrial dyes by an extra-cellular bacterial peroxidase

“…F31.Many types of peroxidases purified from various microbial sources such as bacterial, fungi, yeast and plants etc. were found efficient to decolorize different industrial dyes (Fetyan et al, 2013;Telke et al, 2015, Pandey et al, 2016Ilić Đurđić et al, 2021;Guo et al, 2021). The MnP (manganese-independent peroxidase) purified from Dichomitus squalens was also able to degrade selected azo dyes and anthraquinone dyes (Šušla et al, 2008).…”

Chimeric Biocatalyst Combining Peptidic and Nucleic Acid Components Overcomes the Performance and Limitations of the Native Horseradish Peroxidase

“…The usual routes to construct biomimetic enzymes rely either on the chemical optimization of naturally occurring catalysts − or on the design of new artificial catalysts based on the structural insights gained from studying the enzyme active sites. − A typical example of this approach is the development of horseradish peroxidase (HRP) surrogates: HRP is a hemoprotein (i.e., containing a heme prosthetic group) that is a well-established molecular tool for ELISA assays, immunohistochemical investigations, and immunoblotting analyses. Besides protein engineering − and de novo design of enzyme mimics, − a well-known HRP-mimicking system is the G-quadruplex/hemin DNAzyme, originating in the association of a peculiar four-stranded DNA structure (G-quadruplex) with the HRP cofactor hemin. Alternative efforts have also been invested to provide hemin with a binding site in which it can be catalytically activated using, for example, self-assembled peptides in the aim of encapsulating the catalytic center from the external deactivating aqueous environment , or facilitating new catalytic reactions .…”