A Versatile Peroxidase from the Fungus Bjerkandera adusta Confers Abiotic Stress Tolerance in Transgenic Tobacco Plants

Abstract

White-rot fungi are efficient lignin degraders due to the secretion of lignin peroxidase, manganese peroxidase, laccase, and versatile peroxidase (VP) on decayed wood. The VP is a high-redox-potential enzyme and could be used to detoxify reactive oxygen species (ROS), which accumulate in plants during biotic and abiotic stresses. We cloned the VP gene and expressed it via the Agrobacterium transformation procedure in transgenic tobacco plants to assay their tolerance to different abiotic stress conditions. Thirty independent T2 transgenic VP lines overexpressing the fungal Bjerkandera adustaVP gene were selected on kanamycin. The VP22, VP24, and VP27 lines showed significant manganese peroxidase (MnP) activity. The highest was VP22, which showed 10.87-fold more manganese peroxidase activity than the wild-type plants and led to a 34% increase in plant height and 28% more biomass. The VP22, VP24, and VP27 lines showed enhanced tolerance to drought, 200 mM NaCl, and 400 mM sorbitol. Also, these transgenics displayed significant tolerance to methyl viologen, an active oxygen-generating compound. The present data indicate that overproducing the VP gene in plants increases significantly their biomass and the abiotic stress tolerance. The VP enzyme is an effective biotechnological tool to protect organisms against ROS. In transgenic tobacco plants, it improves drought, salt, and oxidative stress tolerance. Thus, the VP gene represents a great potential for obtaining stress-tolerant crops.

Transcriptome analysis reveals the potential mechanism of polyethylene packing delaying lignification of Pleurotus eryngii

“…As with Laccase, VP (EC 1.111.16, isozymes VPL and VPS) is considered to play a crucial role in the decomposition of lignin by fungi ( Hernandez-Bueno et al, 2021 ). In this study, we analyzed DEGs in the PE treated group versus CK group at three time points and screened out important genes regarding lignin synthesis and decomposition.…”

White Rot Fungi as Tools for the Bioremediation of Xenobiotics: A Review

“…This versatile group of enzymes shows an exceptionally broad substrate spectrum, catalyzing the oxidation of both organic and inorganic compounds in a non-specific manner using hydrogen peroxide (H 2 O 2 ) as an oxidant [ 52 , 101 , 102 , 103 ]. Ligninolytic peroxidases have higher redox potentials compared to laccases, which allows the oxidation of a broad range of recalcitrant substrates [ 46 ].…”

“…It has been accepted that the main heme channel is too narrow for direct contact between the aromatic substrates and the heme cofactor [ 106 ]. Consequently, long-range electron transfer (LRET) from a protein radical at the surface of the enzyme, acting as the substrate oxidizer, to the heme cofactor has been suggested to explain how the oxidation of aromatic substrates, redox mediators and lignin takes place [ 102 ].…”

“…[ 122 ], Trametes [ 123 ] and P. ostreatus [ 107 ]. The catalytic cycle of P. eryngii VPL is a combination of the LiP- and MnP-specific activities ( Figure 5 ); the LiP-characteristic exposed tryptophan residue is found in VPLs (Trp-164) together with the three MnP-characteristic acidic amino acid residues (2 Glu, 1 Asp) involved in Mn 2+ binding [ 102 , 117 ].…”

“… Catalytic cycle of versatile peroxidase (VPLs). Porphyrin: P; non-phenolic high-redox potential aromatic substrate: A, aryl cation radical of A: A•+; phenolic compound: Phe–OH, phenoxyl radical: PheO• (Ruiz-Dueñas et al [ 102 ]). …”