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Feng J, Tian L, Wang W, Yang Y, Li Q, Liu L, Bo H, He C. Effect of RSN1 gene knockout on the adsorption of strontium ions by irradiated Saccharomyces cerevisiae. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2024; 273:107396. [PMID: 38325251 DOI: 10.1016/j.jenvrad.2024.107396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 01/27/2024] [Accepted: 02/02/2024] [Indexed: 02/09/2024]
Abstract
The irradiated Saccharomyces cerevisiae (Y-7) has good biosorption ability for strontium ions. To investigate the mechanism of strontium ion bioaccumulation in Y-7, we employed CRISPR/Cas9 gene editing technology to engineer Saccharomyces cerevisiae Y-7 and knock out the RSN1 gene, successfully constructing a RSN1 gene knockout strain (Y-7-rsn1Δ). When tested for strontium ion adsorption, the Y-7-rsn1Δ strain exhibited decreased capacity for adsorbing strontium ions and increased resistance to strontium ions. The results showed that RSN1 is involved in the transport of Sr2+, and observed significant decreases in intracellular Ca2+ of Y-7-rsn1Δ, indicating a strong correlation between bioaccumulation of Sr2+ and Ca2+. This demonstrated that the adsorption of strontium ions by Y-7 is regulated by the RSN1 gene. The knockout of the RSN1 gene resulted in the shift of the peak positions of carboxyl, amino, amide, hydroxyl, and phosphate groups on the cell surface.
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Affiliation(s)
- Jundong Feng
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China.
| | - Liuxin Tian
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
| | - Weitai Wang
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
| | - Yingqing Yang
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
| | - Qian Li
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
| | - Liang Liu
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
| | - Hongyu Bo
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
| | - Chengyu He
- Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, PR China
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Bhavya G, De Britto S, Satapute P, Geetha N, Jogaiah S. Biofabricated yeast: super-soldier for detoxification of heavy metals. World J Microbiol Biotechnol 2023; 39:148. [PMID: 37022650 DOI: 10.1007/s11274-023-03596-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/27/2023] [Indexed: 04/07/2023]
Abstract
The advances in nanotechnology have shown enormous impacts in environmental technology as a potent weapon for degradation of toxic organic pollutants and detoxification of heavy metals. It is either by in-situ or ex-situ adaptive strategies. Mycoremediation of environmental pollutants has been a success story of the past decade, by employing the wide arsenal of biological capabilities of fungi. Recently, the proficiency and uniqueness of yeast cell surface alterations have encouraged the generation of engineered yeast cells as dye degraders, heavy metal reduction and its recovery, and also as detoxifiers of various hazardous xenobiotic compounds. As a step forward, recent trends in research are towards developing biologically engineered living materials as potent, biocompatible and reusable hybrid nanomaterials. They include chitosan-yeast nanofibers, nanomats, nanopaper, biosilica hybrids, and TiO2-yeast nanocomposites. The nano-hybrid materials contribute significantly as supportive stabilizer, and entrappers, which enhances the biofabricated yeast cells' functionality. This field serves as an eco-friendly cutting-edge cocktail research area. In this review, we highlight recent research on biofabricated yeast cells and yeast-based biofabricated molecules, as potent heavy metals, toxic chemical detoxifiers, and their probable mechanistic properties with future application perspectives.
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Affiliation(s)
- Gurulingaiah Bhavya
- Nanobiotechnology laboratory, Department of Biotechnology, University of Mysore, Manasagangotri, Mysuru, Karnataka, 570006, India
| | - Savitha De Britto
- Division of Biological Sciences, School of Science and Technology, University of Goroka, 441, Goroka, Papua New Guinea
| | - Praveen Satapute
- Laboratory of Plant Healthcare and Diagnostics, Department of Biotechnology and Microbiology, Karnatak University, Dharwad, PG, Karnataka, 580 003, India
| | - Nagaraja Geetha
- Nanobiotechnology laboratory, Department of Biotechnology, University of Mysore, Manasagangotri, Mysuru, Karnataka, 570006, India
| | - Sudisha Jogaiah
- Laboratory of Plant Healthcare and Diagnostics, Department of Biotechnology and Microbiology, Karnatak University, Dharwad, PG, Karnataka, 580 003, India.
- Department of Environmental Science, Central University of Kerala, Tejaswini Hills, Periye (PO), Kasaragod (DT), Periye, Kerala, 671316, India.
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Gao M, Zhou Y, Yan J, Zhu L, Li Z, Hu X, Zhan X. Efficient precious metal Rh(III) adsorption by waste P. pastoris and P. pastoris surface display from high-density culture. JOURNAL OF HAZARDOUS MATERIALS 2022; 427:128140. [PMID: 34979391 DOI: 10.1016/j.jhazmat.2021.128140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/01/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
Rhodium is one of the most used precious metals in catalysis both in laboratory reactions and industrial processes. However, the adsorption of Rh(III) by microorganisms has been seldomly reported. In this work, waste P. pastoris and recombinant P. pastoris with surface-displayed Rh metal peptides (P. pastoris GS-R) from high-density culture were used as novel adsorbents to study Rh(III) adsorption. Under the optimal adsorption conditions of biomass of 0.25 g L-1, pH of 1.2, temperature of 30 °C, and adsorption time of 2 h in simulated wastewater, the maximum adsorption ratios of 55.69% (110.1 mg g-1) and 75.03% (142.11 mg g-1) were achieved for waste P. pastoris and P. pastoris GS-R, respectively. Using the two adsorbents, the adsorption kinetic models fit the quasi-second-order equation, and isotherm models followed the Langmuir and Temkin equations, respectively. P. pastoris GS-R showed high adsorption capacity (48.49%) and selectivity (65.86%) in electroplating wastewater, and the desorption ratio reached 34.49% after treatment with 2 M HNO3 and ultrasonic wave. Therefore, an environmental-friendly strategy was developed for the recovery of Rh(III) and other precious metals by using P. pastoris.
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Affiliation(s)
- Minjie Gao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China
| | - Yuchen Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China
| | - Jiajun Yan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China
| | - Li Zhu
- Wuxi Galaxy Biotech Co. Ltd., Wuxi 214125, PR China
| | - Zhitao Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China
| | - Xiuyu Hu
- China Biotech Fermentation Industry Association, Beijing 100833, PR China
| | - Xiaobei Zhan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China.
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Qi X, Yan W, Cao Z, Ding M, Yuan Y. Current Advances in the Biodegradation and Bioconversion of Polyethylene Terephthalate. Microorganisms 2021; 10:39. [PMID: 35056486 PMCID: PMC8779501 DOI: 10.3390/microorganisms10010039] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/15/2021] [Accepted: 12/20/2021] [Indexed: 01/04/2023] Open
Abstract
Polyethylene terephthalate (PET) is a widely used plastic that is polymerized by terephthalic acid (TPA) and ethylene glycol (EG). In recent years, PET biodegradation and bioconversion have become important in solving environmental plastic pollution. More and more PET hydrolases have been discovered and modified, which mainly act on and degrade the ester bond of PET. The monomers, TPA and EG, can be further utilized by microorganisms, entering the tricarboxylic acid cycle (TCA cycle) or being converted into high value chemicals, and finally realizing the biodegradation and bioconversion of PET. Based on synthetic biology and metabolic engineering strategies, this review summarizes the current advances in the modified PET hydrolases, engineered microbial chassis in degrading PET, bioconversion pathways of PET monomers, and artificial microbial consortia in PET biodegradation and bioconversion. Artificial microbial consortium provides novel ideas for the biodegradation and bioconversion of PET or other complex polymers. It is helpful to realize the one-step bioconversion of PET into high value chemicals.
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Affiliation(s)
- Xinhua Qi
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (X.Q.); (W.Y.); (Z.C.); (Y.Y.)
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
| | - Wenlong Yan
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (X.Q.); (W.Y.); (Z.C.); (Y.Y.)
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
| | - Zhibei Cao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (X.Q.); (W.Y.); (Z.C.); (Y.Y.)
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
| | - Mingzhu Ding
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (X.Q.); (W.Y.); (Z.C.); (Y.Y.)
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
| | - Yingjin Yuan
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (X.Q.); (W.Y.); (Z.C.); (Y.Y.)
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
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Chen Y, Liang J, Chen Z, Wang B, Si T. Genome-Scale Screening and Combinatorial Optimization of Gene Overexpression Targets to Improve Cadmium Tolerance in Saccharomyces cerevisiae. Front Microbiol 2021; 12:662512. [PMID: 34335494 PMCID: PMC8318699 DOI: 10.3389/fmicb.2021.662512] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 06/18/2021] [Indexed: 11/13/2022] Open
Abstract
Heavy metal contamination is an environmental issue on a global scale. Particularly, cadmium poses substantial threats to crop and human health. Saccharomyces cerevisiae is one of the model organisms to study cadmium toxicity and was recently engineered as a cadmium hyperaccumulator. Therefore, it is desirable to overcome the cadmium sensitivity of S. cerevisiae via genetic engineering for bioremediation applications. Here we performed genome-scale overexpression screening for gene targets conferring cadmium resistance in CEN.PK2-1c, an industrial S. cerevisiae strain. Seven targets were identified, including CAD1 and CUP1 that are known to improve cadmium tolerance, as well as CRS5, NRG1, PPH21, BMH1, and QCR6 that are less studied. In the wild-type strain, cadmium exposure activated gene transcription of CAD1, CRS5, CUP1, and NRG1 and repressed PPH21, as revealed by real-time quantitative PCR analyses. Furthermore, yeast strains that contained two overexpression mutations out of the seven gene targets were constructed. Synergistic improvement in cadmium tolerance was observed with episomal co-expression of CRS5 and CUP1. In the presence of 200 μM cadmium, the most resistant strain overexpressing both CAD1 and NRG1 exhibited a 3.6-fold improvement in biomass accumulation relative to wild type. This work provided a new approach to discover and optimize genetic engineering targets for increasing cadmium resistance in yeast.
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Affiliation(s)
- Yongcan Chen
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Shenzhen, China
| | - Jun Liang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zhicong Chen
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Shenzhen, China
| | - Bo Wang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Tong Si
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Shenzhen, China
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Huang H, Jia Q, Jing W, Dahms HU, Wang L. Screening strains for microbial biosorption technology of cadmium. CHEMOSPHERE 2020; 251:126428. [PMID: 32169714 DOI: 10.1016/j.chemosphere.2020.126428] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 03/01/2020] [Accepted: 03/04/2020] [Indexed: 05/23/2023]
Abstract
Heavy metals contaminate the environment and provide a threat to public health through drinking water and food chain. Microbial biosorption technology provides a more economical and competitive solution for bioremediation of toxicants such as heavy metals, and microbial genetic modification may modify microbes towards optimal sorption. It is very important to screen suitable strains for this purpose. In this study, three different types of microorganisms Escherichia coli, Bacillus subtilis and Saccharomyces cerevisiae were isolated and identified, from uncontaminated soils, and compared their sorption differences with respect to cadmium (Cd2+). We evaluated the effects of contact time and initial concentration on Cd2+ uptake, and found pseudo-second-order kinetic models were more suitable to describe biosorption processes. Adsorption isotherms were used to reflect their biosorption capacity. The maximum biosorption capacities of three strains calculated by the Langmuir model were 37.764, 56.497, and 22.437 mg Cd/g biomass, respectively. In bacteria, Cd2+ biosorption mainly occurred on cell wall, while the difference in biosorption between yeast inside and outside the cell was not significant. We found that due to the structural differences, the removal rate of E. coli surface decreased at a high concentration, while S. cerevisiae still had a lower biosorption capacity. FTIR spectroscopy reflected the difference in functional groups involved in biosorption by three strains. SEM-EDS analysis showed the binding of Cd2+ to microorganisms mainly relied on ion exchange mechanism. Based on the above results, we suggested that B. subtilis is more suitable to get genetically modified for heavy metal biosorption.
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Affiliation(s)
- Haojie Huang
- School of Life Science, Shanxi University, Taiyuan, Shanxi province, 030006, China
| | - Qingyun Jia
- School of Life Science, Shanxi University, Taiyuan, Shanxi province, 030006, China
| | - Weixin Jing
- School of Life Science, Shanxi University, Taiyuan, Shanxi province, 030006, China
| | - Hans-Uwe Dahms
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Lan Wang
- School of Life Science, Shanxi University, Taiyuan, Shanxi province, 030006, China.
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Ding J, Zhou Y, Wang C, Peng Z, Mu Y, Tang X, Huang Z. Development of a whole-cell biocatalyst for diisobutyl phthalate degradation by functional display of a carboxylesterase on the surface of Escherichia coli. Microb Cell Fact 2020; 19:114. [PMID: 32471417 PMCID: PMC7260753 DOI: 10.1186/s12934-020-01373-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/25/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Phthalic acid esters (PAEs) are widely used as plasticizers or additives during the industrial manufacturing of plastic products. PAEs have been detected in both aquatic and terrestrial environments due to their overuse. Exposure of PAEs results in human health concerns and environmental pollution. Diisobutyl phthalate is one of the main plasticizers in PAEs. Cell surface display of recombinant proteins has become a powerful tool for biotechnology applications. In this current study, a carboxylesterase was displayed on the surface of Escherichia coli cells, for use as whole-cell biocatalyst in diisobutyl phthalate biodegradation. RESULTS A carboxylesterase-encoding gene (carEW) identified from Bacillus sp. K91, was fused to the N-terminal of ice nucleation protein (inpn) anchor from Pseudomonas syringae and gfp gene, and the fused protein was then cloned into pET-28a(+) vector and was expressed in Escherichia coli BL21(DE3) cells. The surface localization of INPN-CarEW/or INPN-CarEW-GFP fusion protein was confirmed by SDS-PAGE, western blot, proteinase accessibility assay, and green fluorescence measurement. The catalytic activity of the constructed E. coli surface-displayed cells was determined. The cell-surface-displayed CarEW displayed optimal temperature of 45 °C and optimal pH of 9.0, using p-NPC2 as substrate. In addition, the whole cell biocatalyst retained ~ 100% and ~ 200% of its original activity per OD600 over a period of 23 days at 45 °C and one month at 4 °C, exhibiting the better stability than free CarEW. Furthermore, approximately 1.5 mg/ml of DiBP was degraded by 10 U of surface-displayed CarEW cells in 120 min. CONCLUSIONS This work provides a promising strategy of cost-efficient biodegradation of diisobutyl phthalate for environmental bioremediation by displaying CarEW on the surface of E. coli cells. This approach might also provide a reference in treatment of other different kinds of environmental pollutants by displaying the enzyme of interest on the cell surface of a harmless microorganism.
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Affiliation(s)
- Junmei Ding
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China.
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China.
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China.
| | - Yang Zhou
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China
| | - Chaofan Wang
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China
| | - Zheng Peng
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China
| | - Yuelin Mu
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China
| | - Xianghua Tang
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China
| | - Zunxi Huang
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, Yunnan, China.
- Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming, 650500, Yunnan, China.
- Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, Yunnan, China.
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Chen Z, Wang Y, Cheng Y, Wang X, Tong S, Yang H, Wang Z. Efficient biodegradation of highly crystallized polyethylene terephthalate through cell surface display of bacterial PETase. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 709:136138. [PMID: 31887523 DOI: 10.1016/j.scitotenv.2019.136138] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 12/13/2019] [Accepted: 12/14/2019] [Indexed: 05/16/2023]
Abstract
Polyethylene terephthalate (PET) is one of the most widely used plastics in the world. Accumulation of the discarded PET in the environment is creating a global environmental problem. Recently, a bacterial enzyme named PETase was found to have the novel ability to degrade the highly crystallized PET. However, the enzymatic activity of native PETase is still low limiting its possible use in recycling of PET. In this study, we developed a whole-cell biocatalyst by displaying PETase on the surface of yeast (Pichia pastoris) cell to improve its degradation efficiency. Our data shows that PETase could be functionally displayed on the yeast cell with enhanced pH and thermal stability. The turnover rate of the PETase-displaying yeast whole-cell biocatalyst towards highly crystallized PET dramatically increased about 36-fold compared with that of purified PETase. Furthermore, the whole-cell biocatalyst showed stable turnover rate after seven repeated use and under some chemical/solvent conditions, and its ability to degrade different commercial highly crystallized PET bottles. Our results reveal that PETase-displaying whole-cell biocatalyst affords a promising route for efficient biological recycling of PET.
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Affiliation(s)
- Zhuozhi Chen
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China.
| | - Yanyan Wang
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China.
| | - Yingying Cheng
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China.
| | - Xue Wang
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China
| | - Shanwei Tong
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China.
| | - Haitao Yang
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China.
| | - Zefang Wang
- School of Life Sciences, Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin 300457, China.
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Liu M, Kakade A, Liu P, Wang P, Tang Y, Li X. Hg 2+-binding peptide decreases mercury ion accumulation in fish through a cell surface display system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 659:540-547. [PMID: 31096383 DOI: 10.1016/j.scitotenv.2018.12.406] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/26/2018] [Accepted: 12/26/2018] [Indexed: 06/09/2023]
Abstract
Mercury is a potentially toxic trace metal that poses threats to aquatic life and to humans. In this study, a mercury-binding peptide was displayed on the surface of Escherichia coli cells using an N-terminal region ice nucleation protein anchor. The surface-engineered E. coli facilitated selective adsorption of mercury ions (Hg2+) from a solution containing various metal ions. The Hg2+ adsorption capacity of the surface-engineered cell was four-fold higher than that of the original E. coli cells. Approximately 95% of Hg2+ was removed from solution by these whole-cell sorbents. The transformed strains were fed to Carassius auratus, so that the bacteria could colonize fish intestine. Engineered bacteria-fed C. auratus showed significantly less (51.1%) accumulation of total mercury when compared with the group that had not been fed engineered bacteria. The surface-engineered E. coli effectively protected fish against the toxicity of Hg2+ in aquatic environments by adsorbing more Hg2+. Furthermore, the surface-engineered E. coli mitigated microbial diversity changes in the intestine caused by Hg2+ exposure, thereby protecting the intestinal microbial community. This strategy is a novel approach for controlling Hg2+ contamination in fish.
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Affiliation(s)
- Minrui Liu
- Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Apurva Kakade
- Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Pu Liu
- Department of Development Biology Sciences, School of Life Science, Lanzhou University, Lanzhou 730000, China
| | - Peng Wang
- Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China
| | - Yu Tang
- Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China
| | - Xiangkai Li
- Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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