1
|
Wu Y, Sun Y. Cationic Polymers Remarkably Boost Haloalkane Dehalogenase Activity in Organic Solvent Solutions and the Molecular Implications. Molecules 2023; 28:6795. [PMID: 37836637 PMCID: PMC10574148 DOI: 10.3390/molecules28196795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/22/2023] [Accepted: 09/23/2023] [Indexed: 10/15/2023] Open
Abstract
Applications of haloalkane dehalogenase DhaA in biocatalysis are limited by its unfavorable performance in organic solvents. Our previous work proved that mutations of surface positive-charged residues enhanced the organic solvent resistance of DhaA, which inspired us to explore the effect of cationic polymers on DhaA in organic solvents. Remarkably boosted performance was achieved in different organic solvent solutions by introducing cationic polymers, for example, there was a 6.1-fold activity increase with poly(allylamine hydrochloride) and a 5.5-fold activity increase with poly(ethylene imine) in 40 vol.% dimethylsulfoxide. The presence of cationic polymers protected DhaA from damage by organic solvents and increased the substrate concentration around the enzyme-polymer complex. Fluorescence spectroscopy and molecular dynamics simulations revealed that the binding of cationic polymers onto DhaA weakened the interactions between organic solvents and DhaA, decreased the organic solvent solvation level around DhaA, and enhanced the structural stability of DhaA in organic solvents. This comprehensive understanding of the effect of cationic polymers on DhaA can help to broaden the applications of DhaA in organic solvent-involved biocatalysis.
Collapse
Affiliation(s)
- Yin Wu
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China;
| | - Yan Sun
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China;
- Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin 300350, China
| |
Collapse
|
2
|
Wang M, Yu W, Shen L, Zheng H, Guo X, Zhong J, Hu T. Conjugation of haloalkane dehalogenase DhaA with arabinogalactan to increase its stability. J Biotechnol 2021; 335:47-54. [PMID: 34118331 DOI: 10.1016/j.jbiotec.2021.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 04/29/2021] [Accepted: 06/01/2021] [Indexed: 01/21/2023]
Abstract
Haloalkane dehalogenase DhaA can catalyze the hydrolytic cleavage of carbonhalogen bonds, along with production of the corresponding alcohol, a proton and a halide. However, DhaA suffers from poor environmental tolerance, such as sensitivity to high temperature, low pH and hypersaline. Arabinogalactan (AG) is a hydrophilic polysaccharide with highly branched long chains. DhaA was conjugated with AG to improve the environmental stability of DhaA in the present study. Each DhaA was averagely conjugated with 4∼5 AG molecules. Conjugation of AG essentially maintained the enzymatic activity of DhaA (91.4 %) without apparent structural alteration. The hydration layer formed by AG could reduce the solvent accessible area of DhaA and slow the protonation process, thereby improving the pH and high salt stability of DhaA. In particular, the remaining activities of the conjugate (AG-DhaA) were 35.3 % after treatment at pH4.0 for 1 h, and 80.8 % in 1 M NaCl after treatment for 16 h. As compared with DhaA, AG-DhaA showed slightly different kinetic parameters (K M of 1.90 μmol/L and k cat of 2.60 s -1).
Collapse
Affiliation(s)
- Meiqi Wang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China; University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Weili Yu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Lijuan Shen
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - He Zheng
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing, 102205, China
| | - Xuan Guo
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing, 102205, China.
| | - Jinyi Zhong
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing, 102205, China.
| | - Tao Hu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
| |
Collapse
|
3
|
Shan Y, Yu W, Shen L, Guo X, Zheng H, Zhong J, Hu T, Han Y. Conjugation with inulin improves the environmental stability of haloalkane dehalogenase DhaA. Enzyme Microb Technol 2021; 149:109832. [PMID: 34311877 DOI: 10.1016/j.enzmictec.2021.109832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 10/21/2022]
Abstract
Haloalkane dehalogenase DhaA catalyzes the hydrolytic cleavage of carbon-halogen bonds and produces alcohol, a proton and a halide. However, DhaA suffers from the poor environmental stability, such as sensitivity to high temperature, low pH, hypersaline and organic solvent. In order to improve the environmental stability of DhaA, DhaA was covalently conjugated with inulin, a hydrophilic polysaccharide in the present study. Each DhaA was averagely conjugated with 7∼8 inulin molecules. The conjugated inulin could form a hydration layer around DhaA, which increased the conformational rigidity and decreased the entropy of the enzyme. Conjugation of inulin maintained 75.5 % of the enzymatic activity of DhaA and slightly altered the structure of DhaA. As compared with DhaA, the conjugate (inu-DhaA) showed slightly different kinetic parameters (Km of 2.9 μmol/L and Kcat of 1.0 s-1). Inulin conjugation could delay the structural unfolding and/or slow the protonation process of DhaA under undesirable environment, including the long-term storage, low pH, hypersaline and organic solvent stability. As a result, the environmental stability of DhaA was markedly increased upon conjugation with inulin. Thus, inulin conjugation was an effective approach to enhance the environmental stability of DhaA.
Collapse
Affiliation(s)
- Yue Shan
- College of Life Sciences, Liaoning Normal University, Dalian, 116081, Liaoning Province, China; State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Weili Yu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Lijuan Shen
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Xuan Guo
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing, 102205, China
| | - He Zheng
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing, 102205, China
| | - Jinyi Zhong
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing, 102205, China.
| | - Tao Hu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Yinglun Han
- College of Life Sciences, Liaoning Normal University, Dalian, 116081, Liaoning Province, China.
| |
Collapse
|
4
|
Zheng H, Zheng YC, Cui Y, Zhu JJ, Zhong JY. Study on effects of co-solvents on the structure of DhaA by molecular dynamics simulation. J Biomol Struct Dyn 2020; 39:5999-6007. [PMID: 32696722 DOI: 10.1080/07391102.2020.1796801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
With the increasing application of enzymes in various research fields, the choices of co-solvents in enzymatic preparations which directly related to the catalytic activity have been attracted attention. Thus, researching on the stabilization or destabilization behaviors of enzymes in different solvents is extremely essential. In this study, the structural changes of DhaA in two typical aprotic co-solvents (acetonitrile and tetrahydrofuran) were firstly investigated by molecular dynamics (MD) simulation. The simulation results revealed the strong van der Waals force between co-solvents and DhaA which could induce the structural change of enzyme. Interestingly, the differences of molecular size and the electrostatic force with enzyme of two co-solvents led to quite different influences on DhaA. As for acetonitrile, solvent molecules could penetrate into the catalytic site of DhaA which promoted by the electrostatic interaction. On the contrary, tetrahydrofuran molecules were mainly distributed around the catalytic site due to the relative weak electrostatic interaction and steric resistance effect. It can be concluded that different co-solvent can affect the key domains, substrate pathway and catalytic pocket of DhaA.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- He Zheng
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Yong-Chao Zheng
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Yan Cui
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Jian-Jun Zhu
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Jin-Yi Zhong
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| |
Collapse
|
5
|
Xu W, Zhang W, Guang C, Zhang T, Mu W. A close look on the effect of polyethylene glycol on the levansucrase thermostability: a case study of Brenneria sp. levansucrase. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:6315-6323. [PMID: 31260112 DOI: 10.1002/jsfa.9908] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 06/26/2019] [Accepted: 06/27/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND To increase the low residual activity of levansucrase during long-time processing, an enhancement of its weak thermostability is needed. Here, the effect of metal ions and polyethylene glycol (PEG) on the thermostability of levansucrase from Brenneria sp. EniD312 were studied and evaluated. The residual activity was determined and the protein structure was evaluated by circular dichroism spectrum, fluorescence intensity (FI), and surface hydrophobicity (S0 ). RESULTS As a result of incubation with 10% (w/v) PEG 4000, the enzyme activity was increased by 1.24-fold. After incubation with 5% PEG 4000 for 6 h, the residual activity at 35 and 45 °C was decreased to 55% and 60% of the initial activity, with an increase of 1.2- and 3.3-fold than the wild-type enzyme. Furthermore, the random coil content of enzyme was decreased from 53% of the wild-type enzyme to 33.9% of the PEG pre-incubated enzyme. Additionally, the FI was maximally increased and the S0 was decreased from 117 to 69. CONCLUSION All of these results suggested that after incubation with PEG 4000, the secondary and tertiary structure of wild-type enzyme could be greatly maintained and then its thermostability could be increased. This study was the first report on the enhancement of levansucrase thermostability by PEG incubation and might be a good guideline to other researches on levansucrase. © 2019 Society of Chemical Industry.
Collapse
Affiliation(s)
- Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Tao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| |
Collapse
|
6
|
Zheng H, Yu WL, Guo X, Zhao YZ, Cui Y, Hu T, Zhong JY. An effective immobilized haloalkane dehalogenase DhaA from Rhodococcus rhodochrous by adsorption, crosslink and PEGylation on meso-cellular foam. Int J Biol Macromol 2018; 125:1016-1023. [PMID: 30576728 DOI: 10.1016/j.ijbiomac.2018.12.127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 12/01/2018] [Accepted: 12/16/2018] [Indexed: 12/30/2022]
Abstract
Haloalkane dehalogenase DhaA catalyzes the hydrolysis of halogenated compounds by cleavage of the carbon-halogen bond. However, DhaA suffers from poor environmental stability and difficult recovery, which significantly increase the cost of DhaA. Here, an effective enzyme immobilization strategy was developed to overcome the disadvantages of DhaA. DhaA was physically absorbed with amine-functionalized meso-cellular foam (MCF). The MCF-absorbed DhaA (MD) was intermolecularly crosslinked with 8-arm PEG N‑hydroxysuccinimide ester and then PEGylated by maleimide-thiol chemistry. DhaA from Rhodococcus rhodochrous was absorbed at a loading capacity of 100 mg/g in MD. The bulk crystallinity and morphology of MCF were largely maintained. The immobilized DhaA (MD-P1-P2) showed a lower Michaelis constant (Km, 0.588 mM) than DhaA (0.905 mM), along with an extremely low leaching ratio of DhaA (1.1%) from MCF. MD-P1-P2 exhibited a high stability in the extreme environmental conditions, as reflected by the remaining activity of 99.8% in 40% (v/v) DMSO for 5 h, 87.3% in 3 M urea solution for 1 h, 25.9% at pH 3.0, and 51.8% at room temperature for 30 days. Thus, our study was expected to develop an effective immobilized DhaA for practical application.
Collapse
Affiliation(s)
- He Zheng
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing 102205, China
| | - Wei-Li Yu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Xuan Guo
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing 102205, China
| | - Yuan-Zhong Zhao
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing 102205, China
| | - Yan Cui
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing 102205, China
| | - Tao Hu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Jin-Yi Zhong
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Beijing 102205, China.
| |
Collapse
|