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

Nancy Sofia Hernández-Bueno,Ramón Suárez-Rodríguez,Edgar Balcázar-López,Gabriel Iturriaga,José Augusto Ramírez-Trujillo,Jorge Luis Folch-Mallol

doi:10.3390/plants10050859

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 adusta VP 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.

Highlights

Introduction published maps and institutional affilReactive oxygen species (ROS) control different signaling pathways in plants involved in stress and pathogen responses, photosynthesis, programmed cell death, hormonal action growth, and development [1,2]
Gene from Bjerkandera adusta, and showed that it can mitigate oxidative stress induced by paraquat, salt- (NaCl), drought- and osmotic-stress. These findings strongly suggest that the versatile peroxidase (VP) gene can be used as a tool to contend with different abiotic stresses
To isolate a gene encoding a versatile peroxidase (VP) from Bjerkandera adusta, two oligonucleotides deduced from the Bjerkandera sp. strain B33/3

Summary

Introduction

Reactive oxygen species (ROS) control different signaling pathways in plants involved in stress and pathogen responses, photosynthesis, programmed cell death, hormonal action growth, and development [1,2]. ROS might cause cellular injury by reacting with biological compounds, and their cell damage is one of the major mechanisms underlying the biotic and abiotic stresses including drought, high light, wounding, salt, or pathogen infection [3]. Cells have evolved highly regulated mechanisms to maintain a balance between ROS production and breakdown [4]. Peroxidase (EC 1.11.1.7) oxidizes a vast array of compounds (hydrogen donors) in the presence of H2 O2. Heme-containing peroxidases form a superfamily of enzymes responsible for numerous biosynthetic and degradative functions.

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Conclusion