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Gao S, Ma D, Wang Y, Zhang A, Wang X, Chen K. Whole-cell catalyze L-dopa to dopamine via co-expression of transport protein AroP in Escherichia coli. BMC Biotechnol 2023; 23:33. [PMID: 37644483 PMCID: PMC10463401 DOI: 10.1186/s12896-023-00794-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 07/18/2023] [Indexed: 08/31/2023] Open
Abstract
Dopamine is high-value compound of pharmaceutical interest, but its industrial scale production mostly focuses on chemical synthesis, possessing environment pollution. Bio-manufacturing has caused much attention for its environmental characteristic. Resting cells were employed to as biocatalysts with extraordinary advantages like offering stable surroundings, the inherent presence of expensive cofactors. In this study, whole-cell bioconversion was employed to convert dopa to dopamine. To increase the titer and yield of dopamine production through whole-cell catalysis, three kinds of aromatic amino acid transport protein, AroP, PheP and TyrP, were selected to be co-expressed. The effects of the concentration of L-dopa, pyridoxal-5'- phosphate (PLP), reaction temperature and pH were characterized for improvement of bioconversion. Under optimal conditions, dopamine titer reached 1.44 g/L with molar yield of 46.3%, which is 6.62 times than that of initial conditions. The catalysis productivity of recombinant E. coli co-expressed L-dopa decarboxylase(DDC) and AroP was further enhanced by repeated cell recycling, which maintained over 50% of its initial ability with eight consecutive catalyses. This study was the first to successfully bioconversion of dopamine by whole-cell catalysis. This research provided reference for whole-cell catalysis which is hindered by cell membrane.
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Affiliation(s)
- Siyuan Gao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Ding Ma
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Yongtao Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Alei Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Xin Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China.
| | - Kequan Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
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2
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Cui L, Cheng C, Qiu Y, Jiang T, He B. Excretory overexpression of hydrophobins as multifunctional biosurfactants in E. coli. Int J Biol Macromol 2020; 165:1296-1302. [DOI: 10.1016/j.ijbiomac.2020.09.206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 10/23/2022]
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3
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Caro MDP, Holton N, Conti G, Venturuzzi AL, Martínez‐Zamora MG, Zipfel C, Asurmendi S, Díaz‐Ricci JC. The fungal subtilase AsES elicits a PTI-like defence response in Arabidopsis thaliana plants independently of its enzymatic activity. MOLECULAR PLANT PATHOLOGY 2020; 21:147-159. [PMID: 31769595 PMCID: PMC6988430 DOI: 10.1111/mpp.12881] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Acremonium strictum elicitor subtilisin (AsES) is a 34-kDa serine-protease secreted by the strawberry fungal pathogen A. strictum. On AsES perception, a set of defence reactions is induced, both locally and systemically, in a wide variety of plant species and against pathogens of alternative lifestyles. However, it is not clear whether AsES proteolytic activity is required for triggering a defence response or if the protein itself acts as an elicitor. To investigate the necessity of the protease activity to activate the defence response, AsES coding sequences of the wild-type gene and a mutant on the active site (S226A) were cloned and expressed in Escherichia coli. Our data show that pretreatment of Arabidopsis plants with inactive proteins, i.e. inhibited with phenylmethylsulphonyl fluoride (PMSF) and mutant, resulted in an increased systemic resistance to Botrytis cinerea and expression of defence-related genes in a temporal manner that mimics the effect already reported for the native AsES protein. The data presented in this study indicate that the defence-eliciting property exhibited by AsES is not associated with its proteolytic activity. Moreover, the enhanced expression of some immune marker genes, seedling growth inhibition and the involvement of the co-receptor BAK1 observed in plants treated with AsES suggests that AsES is being recognized as a pathogen-associated molecular pattern by a leucine-rich repeat receptor. The understanding of the mechanism of action of AsES will contribute to the development of new breeding strategies to confer durable resistance in plants.
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Affiliation(s)
- María del Pilar Caro
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET‐UNT, and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNTSan Miguel de TucumánArgentina
| | - Nicholas Holton
- The Sainsbury LaboratoryUniversity of East AngliaNorwich Research Park, NorwichUnited Kingdom
| | - Gabriela Conti
- Instituto de Agrobiotecnología y Biología Molecular – IABiMo – INTA – CONICET, Instituto de Biotecnología, Centro de Investigaciones en Ciencias Agronómicas y Veterinarias, Instituto Nacional de Tecnología AgropecuariaHurlinghamArgentina
| | - Andrea Laura Venturuzzi
- Instituto de Agrobiotecnología y Biología Molecular – IABiMo – INTA – CONICET, Instituto de Biotecnología, Centro de Investigaciones en Ciencias Agronómicas y Veterinarias, Instituto Nacional de Tecnología AgropecuariaHurlinghamArgentina
| | - Martin Gustavo Martínez‐Zamora
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET‐UNT, and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNTSan Miguel de TucumánArgentina
| | - Cyril Zipfel
- The Sainsbury LaboratoryUniversity of East AngliaNorwich Research Park, NorwichUnited Kingdom
- Institute of Plant and Microbial Biology and Zürich‐Basel Plant Science CenterUniversity of ZürichZürichSwitzerland
| | - Sebastian Asurmendi
- Instituto de Agrobiotecnología y Biología Molecular – IABiMo – INTA – CONICET, Instituto de Biotecnología, Centro de Investigaciones en Ciencias Agronómicas y Veterinarias, Instituto Nacional de Tecnología AgropecuariaHurlinghamArgentina
| | - Juan Carlos Díaz‐Ricci
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET‐UNT, and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNTSan Miguel de TucumánArgentina
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Development of Versatile Vectors for Heterologous Expression in Bacillus. Microorganisms 2018; 6:microorganisms6020051. [PMID: 29875331 PMCID: PMC6027494 DOI: 10.3390/microorganisms6020051] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/01/2018] [Accepted: 06/05/2018] [Indexed: 01/22/2023] Open
Abstract
The discovery of new enzymes for industrial application relies on a robust discovery pipeline. Such a pipeline should facilitate efficient molecular cloning, recombinant expression and functional screening procedures. Previously, we have developed a vector set for heterologous expression in Escherichia coli. Here, we supplement the catalogue with vectors for expression in Bacillus. The vectors are made compatible with a versatile cloning procedure based on type IIS restriction enzymes and T4 DNA ligase, and encompass an effective counter-selection procedure and complement the set of vectors with options for secreted expression. We validate the system with expression of recombinant subtilisins, which are generally challenging to express in a heterologous system. The complementarity of the E. coli and Bacillus systems allows rapid switching between the two commonly used hosts without comprehensive intermediate cloning steps. The vectors described are not limited to the expression of certain enzymes, but could also be applied for the expression of other enzymes for more generalized enzyme discovery or development.
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5
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Kleiner-Grote GRM, Risse JM, Friehs K. Secretion of recombinant proteins from E. coli. Eng Life Sci 2018; 18:532-550. [PMID: 32624934 DOI: 10.1002/elsc.201700200] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 03/07/2018] [Accepted: 03/13/2018] [Indexed: 11/10/2022] Open
Abstract
The microorganism Escherichia coli is commonly used for recombinant protein production. Despite several advantageous characteristics like fast growth and high protein yields, its inability to easily secrete recombinant proteins into the extracellular medium remains a drawback for industrial production processes. To overcome this limitation, a multitude of approaches to enhance the extracellular yield and the secretion efficiency of recombinant proteins have been developed in recent years. Here, a comprehensive overview of secretion mechanisms for recombinant proteins from E. coli is given and divided into three main sections. First, the structure of the E. coli cell envelope and the known natural secretion systems are described. Second, the use and optimization of different one- or two-step secretion systems for recombinant protein production, as well as further permeabilization methods are discussed. Finally, the often-overlooked role of cell lysis in secretion studies and its analysis are addressed. So far, effective approaches for increasing the extracellular protein concentration to more than 10 g/L and almost 100% secretion efficiency exist, however, the large range of optimization methods and their combinations suggests that the potential for secretory protein production from E. coli has not yet been fully realized.
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Affiliation(s)
| | - Joe M Risse
- Fermentation Engineering Bielefeld University Bielefeld Germany.,Center for Biotechnology Bielefeld University Bielefeld Germany
| | - Karl Friehs
- Fermentation Engineering Bielefeld University Bielefeld Germany.,Center for Biotechnology Bielefeld University Bielefeld Germany
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Cheng C, Wu S, Cui L, Wu Y, Jiang T, He B. A novel Ffu fusion system for secretory expression of heterologous proteins in Escherichia coli. Microb Cell Fact 2017; 16:231. [PMID: 29268791 PMCID: PMC5740907 DOI: 10.1186/s12934-017-0845-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 12/13/2017] [Indexed: 11/13/2022] Open
Abstract
Background The high level of excretion and rapid folding ability of β-fructofuranosidase (β-FFase) in Escherichia coli has suggested that β-FFase from Arthrobacter arilaitensis NJEM01 can be developed as a fusion partner. Methods Based on the modified Wilkinson and Harrison algorithm and the preliminary verification of the solubility-enhancing ability of β-FFase truncations, three β-FFase truncations (i.e., Ffu209, Ffu217, and Ffu312) with a native signal peptide were selected as novel Ffu fusion tags. Four difficult-to-express protein models; i.e., CARDS TX, VEGFR-2, RVs and Omp85 were used in the assessment of Ffu fusion tags. Results The expression levels and solubility of each protein were markedly enhanced by the Ffu fusion system. Each protein had a favorable Ffu tag. The Ffu fusion tags performed preferably when compared with the well-known fusion tags MBP and NusA. Strikingly, it was confirmed that Ffu fusion proteins were secreted into the periplasm by the periplasmic analysis and N-amino acid sequence analysis. Further, efficient excretion of HV3 with defined anti-thrombin activity was obtained when it was fused with the Ffu312 tag. Moreover, HV3 remained soluble and demonstrated notable anti-thrombin activity after the removal of the Ffu312 tag by enterokinase. Conclusions Observations from this work not only complements fusion technologies, but also develops a novel and effective secretory system to solve key issues that include inclusion bodies and degradation when expressing heterologous proteins in E. coli, especially for proteins that require disulfide bond formation, eukaryotic-secreted proteins, and membrane-associated proteins. Electronic supplementary material The online version of this article (10.1186/s12934-017-0845-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cheng Cheng
- School of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China
| | - Shanshan Wu
- Wuxi AppTec (Suzhou) Testing Technology Co.,Ltd., 1336 Wuzhong Avenue, Xinzhiyuan Building B, Wuzhong District, Suzhou, 215104, Jiangsu, China
| | - Lupeng Cui
- School of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China
| | - Yulu Wu
- School of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China
| | - Tianyue Jiang
- School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China
| | - Bingfang He
- School of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China. .,School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China.
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7
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Bjerga GEK, Arsın H, Larsen Ø, Puntervoll P, Kleivdal HT. A rapid solubility-optimized screening procedure for recombinant subtilisins in E. coli. J Biotechnol 2016; 222:38-46. [DOI: 10.1016/j.jbiotec.2016.02.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 02/01/2016] [Accepted: 02/03/2016] [Indexed: 02/08/2023]
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8
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Jeschek M, Panke S, Ward T. Periplasmic Screening for Artificial Metalloenzymes. Methods Enzymol 2016; 580:539-56. [DOI: 10.1016/bs.mie.2016.05.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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9
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Nam DH, Ge X. Direct production of functional matrix metalloproteinase--14 without refolding or activation and its application for in vitro inhibition assays. Biotechnol Bioeng 2015; 113:717-23. [PMID: 26416249 DOI: 10.1002/bit.25840] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 09/05/2015] [Accepted: 09/21/2015] [Indexed: 02/06/2023]
Abstract
Human matrix metalloproteinase (MMP)-14, a membrane-bound zinc endopeptidase, is one of the most important cancer targets because it plays central roles in tumor growth and invasion. Large amounts of active MMP-14 are required for cancer research and the development of chemical or biological MMP-14 inhibitors. Current methods of MMP-14 production through refolding and activation are labor-intensive, time-consuming, and often associated with low recovery rates, lot-to-lot variation and heterogeneous products. Here, we report direct production of the catalytic domain of MMP-14 in the periplasmic space of Escherichia coli. 0.5 mg/L of functional MMP-14 was produced without tedious refolding or problematic activation process. MMP-14 prepared by simple periplasmic treatment can be readily utilized to evaluate the potencies of chemical and antibody-based inhibitors. Furthermore, co-expression of both MMP-14 and antibody Fab fragments in the periplasm facilitated inhibitory antibody screening by avoiding purification of MMP-14 or Fabs. We expect this MMP-14 expression strategy can expedite the development of therapeutic drugs targeting MMPs with biological significance.
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Affiliation(s)
- Dong Hyun Nam
- Department of Chemical and Environmental Engineering, University of California, 900 University Ave Riverside, Riverside, 92521, California
| | - Xin Ge
- Department of Chemical and Environmental Engineering, University of California, 900 University Ave Riverside, Riverside, 92521, California.
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10
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Auto-induction-based Rapid Evaluation of Extracellular Enzyme Expression from Lac Operator-involved Recombinant Escherichia coli. Appl Biochem Biotechnol 2014; 174:2516-26. [DOI: 10.1007/s12010-014-1201-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 08/22/2014] [Indexed: 12/30/2022]
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11
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Sakurai Y, Anzai I, Furukawa Y. A primary role for disulfide formation in the productive folding of prokaryotic Cu,Zn-superoxide dismutase. J Biol Chem 2014; 289:20139-49. [PMID: 24917671 DOI: 10.1074/jbc.m114.567677] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Enzymatic activation of Cu,Zn-superoxide dismutase (SOD1) requires not only binding of a catalytic copper ion but also formation of an intramolecular disulfide bond. Indeed, the disulfide bond is completely conserved among all species possessing SOD1; however, it remains obscure how disulfide formation controls the enzymatic activity of SOD1. Here, we show that disulfide formation is a primary event in the folding process of prokaryotic SOD1 (SodC) localized to the periplasmic space. Escherichia coli SodC was found to attain β-sheet structure upon formation of the disulfide bond, whereas disulfide-reduced SodC assumed little secondary structure even in the presence of copper and zinc ions. Moreover, reduction of the disulfide bond made SodC highly susceptible to proteolytic degradation. We thus propose that the thiol-disulfide status in SodC controls the intracellular stability of this antioxidant enzyme and that the oxidizing environment of the periplasm is required for the enzymatic activation of SodC.
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Affiliation(s)
- Yasuyuki Sakurai
- From the Laboratory for Mechanistic Chemistry of Biomolecules, Department of Chemistry, Keio University, Yokohama, Kanagawa 223-8522 Japan
| | - Itsuki Anzai
- From the Laboratory for Mechanistic Chemistry of Biomolecules, Department of Chemistry, Keio University, Yokohama, Kanagawa 223-8522 Japan
| | - Yoshiaki Furukawa
- From the Laboratory for Mechanistic Chemistry of Biomolecules, Department of Chemistry, Keio University, Yokohama, Kanagawa 223-8522 Japan
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12
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Dedavid e Silva L, Tirloni L, Loss-Morais G, Margis R, da Silva Vaz I, Macedo A, Termignoni C. A recombinant subtilisin with keratinolytic and fibrin(ogen)olytic activity. Process Biochem 2014. [DOI: 10.1016/j.procbio.2014.03.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Moreira S, Castanheira P, Casal M, Faro C, Gama M. Expression of the functional carbohydrate-binding module (CBM) of human laforin. Protein Expr Purif 2010; 74:169-74. [PMID: 20600946 DOI: 10.1016/j.pep.2010.06.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 06/23/2010] [Accepted: 06/23/2010] [Indexed: 10/19/2022]
Abstract
Laforin is a human protein associated with the glycogen metabolism, composed of two structurally and functionally independent domains: a phosphatase catalytic domain and a substrate-binding module with glycogen and starch affinity. The main goal of this work is the development of a methodology for the expression of the so far poorly characterized carbohydrate-binding module (CBM) of laforin, allowing its study and development of biomedical applications. The laforin's CBM sequence was originally cloned by PCR from a human muscle cDNA library. The recombinant protein, containing laforin's CBM fused to an Arg-Gly-Asp sequence (RGD), was cloned and expressed using vector pET29a and recovered as inclusion bodies (IBs). Refolding of the IBs allowed the purification of soluble, dimeric and functional protein, according to adsorption assays using starch and glycogen. Several other experimental approaches, using both bacteria and yeast, were unsuccessfully tested, pointing towards the difficulties in producing the heterologous protein. Indeed, this is the first work reporting the production of the functional CBM from human laforin.
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Affiliation(s)
- Susana Moreira
- IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Braga, Portugal
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14
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Fernandes P, Cabral JMS. Applied Biocatalysis: An Overview. Ind Biotechnol (New Rochelle N Y) 2010. [DOI: 10.1002/9783527630233.ch6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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15
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Lee LL, Ha H, Chang YT, DeLisa MP. Discovery of amyloid-beta aggregation inhibitors using an engineered assay for intracellular protein folding and solubility. Protein Sci 2009; 18:277-86. [PMID: 19177561 DOI: 10.1002/pro.33] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Genetic and biochemical studies suggest that Alzheimer's disease (AD) is caused by a series of events initiated by the production and subsequent aggregation of the Alzheimer's amyloid beta peptide (Abeta), the so-called amyloid cascade hypothesis. Thus, a logical approach to treating AD is the development of small molecule inhibitors that either block the proteases that generate Abeta from its precursor (beta- and gamma-secretases) or interrupt and/or reverse Abeta aggregation. To identify potent inhibitors of Abeta aggregation, we have developed a high-throughput screen based on an earlier selection that effectively paired the folding quality control feature of the Escherichia coli Tat protein export system with aggregation of the 42-residue AD pathogenesis effecter Abeta42. Specifically, a tripartite fusion between the Tat-dependent export signal ssTorA, the Abeta42 peptide and the beta-lactamase (Bla) reporter enzyme was found to be export incompetent due to aggregation of the Abeta42 moiety. Here, we reasoned that small, cell-permeable molecules that inhibited Abeta42 aggregation would render the ssTorA-Abeta42-Bla chimera competent for Tat export to the periplasm where Bla is active against beta-lactam antibiotics such as ampicillin. Using a fluorescence-based version of our assay, we screened a library of triazine derivatives and isolated four nontoxic, cell-permeable compounds that promoted efficient Tat-dependent export of ssTorA-Abeta42-Bla. Each of these was subsequently shown to be a bona fide inhibitor of Abeta42 aggregation using a standard thioflavin T fibrillization assay, thereby highlighting the utility of our bacterial assay as a useful screen for antiaggregation factors under physiological conditions.
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Affiliation(s)
- Li Ling Lee
- Cornell University, Ithaca, New York 14853, USA
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16
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Araújo R, Cavaco‐Paulo A, Casal M. Strategies towards the Functionalization of Subtilisin E from Bacillus subtilis for Wool Finishing Applications. Eng Life Sci 2008. [DOI: 10.1002/elsc.200700056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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17
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Chen RR. Permeability issues in whole-cell bioprocesses and cellular membrane engineering. Appl Microbiol Biotechnol 2007; 74:730-8. [PMID: 17221194 DOI: 10.1007/s00253-006-0811-x] [Citation(s) in RCA: 160] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 12/14/2006] [Accepted: 12/17/2006] [Indexed: 10/23/2022]
Abstract
Nutrient uptake and waste excretion are among the many important functions of the cellular membrane. While permitting nutrients into the cell, the cellular membrane system evolves to guide against noxious agents present in the environment from entering the intracellular milieu. The semipermeable nature of the membrane is at odds with biomolecular engineers in their endeavor of using microbes as cell factory. The cellular membrane often retards the entry of substrate into the cellular systems and prevents the product from being released from the cellular system for an easy recovery. Consequently, productivities of whole-cell bioprocesses such as biocatalysis, fermentation, and bioremediations are severely compromised. For example, the rate of whole-cell biocatalysis is usually 1-2 orders of magnitude slower than that of the isolated enzymes. When product export cannot keep pace with the production rate, intracellular product accumulation quickly leads to a halt of production due to product inhibition. While permeabilization via chemical or physical treatment of cell membrane is effective in small-scale process, large-scale implementation is problematic. Molecular engineering approach recently emerged as a much better alternative. Armed with increasingly sophisticated tools, biomolecular engineers are following nature's ingenuity to derive satisfactory solutions to the permeability problem. This review highlights these exciting molecular engineering achievements.
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Affiliation(s)
- Rachel Ruizhen Chen
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, USA.
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18
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Choi JH, Keum KC, Lee SY. Production of recombinant proteins by high cell density culture of Escherichia coli. Chem Eng Sci 2006. [DOI: 10.1016/j.ces.2005.03.031] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ni Y, Chen RR. Accelerating whole-cell biocatalysis by reducing outer membrane permeability barrier. Biotechnol Bioeng 2005; 87:804-11. [PMID: 15329939 DOI: 10.1002/bit.20202] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Whole-cell biocatalysts are preferred in many biocatalysis applications. However, due to permeability barriers imposed by cell envelopes, whole-cell catalyzed reactions are reportedly 10-100-fold slower than reactions catalyzed by free enzymes. In this study, we accelerated whole-cell biocatalysis by reducing the membrane permeability barrier using molecular engineering approaches. Escherichia coli cells with genetically altered outer membrane structures were used. Specifically, a lipopolysaccarides mutant SM101 and a Braun's lipoprotein mutant E609L were used along with two model substrates that differ substantially in size and hydrophobicity, nitrocefin, and a tetrapeptide N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide. The reduction of the outer membrane permeability by genetic methods led to significant increases (up to 380%) in reaction rates of whole-cell catalyzed reactions. The magnitude of increase in biocatalysis rates was dependent on the substrates and on the nature of mutations introduced in the outer membrane structure. Notably, mutations in outer membrane can render the outer membrane completely permeable to one substrate, a barrierless condition that maximizes the reaction rate. The impact of the mutations introduced on the permeability barrier of the membranes was compared to the impact of polymixin B nonapeptide, a known potent permeabilizer acting on lipopolysaccharides. Our results suggest that genetic modifications to enhance the permeability of hydrophilic molecules should target the Lipid A region. However, strategies other than reduction of Lipid A synthesis should be considered. As we have demonstrated with tetrapeptide, membrane engineering can be much more effective in reducing a permeability barrier than are exogenous permeabilizers. This work, to our knowledge, is the first use of a molecular membrane engineering approach to address substrate permeability limitations encountered in biocatalysis applications.
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Affiliation(s)
- Ye Ni
- Chemical Engineering Department, Virginia Commonwealth University, 601 W. Main St., Richmond 23284-3028, USA
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20
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Sroga GE, Dordick JS. Periplasmic Expression as a Basis for Whole Cell Kinetic Screening of Unnatural Enzyme Reactivities. Methods Enzymol 2004; 388:145-56. [PMID: 15289068 DOI: 10.1016/s0076-6879(04)88013-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- Grazyna E Sroga
- Chemical and Biological Engineering Department, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
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