1
|
Li R, Yang Y, Cao H, Peng X, Yu Q, He L, Chen J, Xiang L, Liu W. Heterologous expression of the tobacco metallothionein gene NtMT2F confers enhanced tolerance to Cd stress in Escherichia coli and Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 195:247-255. [PMID: 36645929 DOI: 10.1016/j.plaphy.2023.01.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Heavy metal pollution in the soil is a serious threat to crop growth and human health. Metallothionein (MT) is a low molecular weight protein that is rich in cysteine, which can effectively alleviate the toxicity of heavy metals in plants. In this study, a novel metallothionein encoding gene, NtMT2F, was cloned from the Cd-hyperaccumulator tobacco and heterologously expressed in E. coli and A. thaliana to verify its biological function. Recombinant E. coli incubated with NtMT2F effectively resisted heavy metal stress, particularly Cd. The recombinant strain grew significantly faster and had a higher content of Cd than the control. Mutations in the C-terminal Cys residues of NtMT2F significantly reduced its ability to chelate heavy metals. The overexpression of NtMT2F significantly enhanced resistance to Cd toxicity in transgenic A. thaliana. The germination rate, root length, and fresh weight of transgenic plants under Cd stress were higher than those of the wild type (WT). The contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) were lower than those of the WT. In addition, the activities of anti-peroxidase enzymes including glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), were significantly increased in the transgenic plants. The results of this study indicate that NtMT2F significantly improved the tolerance of microorganisms and plants to Cd and could be an important candidate protein for phytoremediation.
Collapse
Affiliation(s)
- Rui Li
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Ya Yang
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Hanping Cao
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Xiang Peng
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Qin Yu
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Linshen He
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Ji Chen
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Lien Xiang
- College of Environmental Science & Engineering, China West Normal University, Nanchong, 637009, China
| | - Wanhong Liu
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China.
| |
Collapse
|