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Pekarsky A, Mihalyi S, Weiss M, Limbeck A, Spadiut O. Depletion of Boric Acid and Cobalt from Cultivation Media: Impact on Recombinant Protein Production with Komagataella phaffii. Bioengineering (Basel) 2020; 7:bioengineering7040161. [PMID: 33322107 PMCID: PMC7763993 DOI: 10.3390/bioengineering7040161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/09/2020] [Accepted: 12/11/2020] [Indexed: 11/23/2022] Open
Abstract
The REACH regulation stands for “Registration, Evaluation, Authorization and Restriction of Chemicals” and defines certain substances as harmful to human health and the environment. This urges manufacturers to adapt production processes. Boric acid and cobalt dichloride represent such harmful ingredients, but are commonly used in yeast cultivation media. The yeast Komagataella phaffii (Pichia pastoris) is an important host for heterologous protein production and compliance with the REACH regulation is desirable. Boric acid and cobalt dichloride are used as boron and cobalt sources, respectively. Boron and cobalt support growth and productivity and a number of cobalt-containing enzymes exist. Therefore, depletion of boric acid and cobalt dichloride could have various negative effects, but knowledge is currently scarce. Herein, we provide an insight into the impact of boric acid and cobalt depletion on recombinant protein production with K. phaffii and additionally show how different vessel materials affect cultivation media compositions through leaking elements. We found that boric acid could be substituted through boron leakiness from borosilicate glassware. Furthermore, depletion of boric acid and cobalt dichloride neither affected high cell density cultivation nor cell morphology and viability on methanol. However, final protein quality of three different industrially relevant enzymes was affected in various ways.
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Affiliation(s)
- Alexander Pekarsky
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorferstrasse 1a, 1060 Vienna, Austria; (A.P.); (S.M.)
| | - Sophia Mihalyi
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorferstrasse 1a, 1060 Vienna, Austria; (A.P.); (S.M.)
| | - Maximilian Weiss
- Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9/164-I2AC, 1060 Vienna, Austria; (M.W.); (A.L.)
| | - Andreas Limbeck
- Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9/164-I2AC, 1060 Vienna, Austria; (M.W.); (A.L.)
| | - Oliver Spadiut
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorferstrasse 1a, 1060 Vienna, Austria; (A.P.); (S.M.)
- Correspondence: ; Tel.: +43-1-58801-166473
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A Novel Methanol-Free Platform for Extracellular Expression of rhGM-CSF in Pichia pastoris. Mol Biotechnol 2019; 61:521-527. [PMID: 31054084 DOI: 10.1007/s12033-019-00182-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The production of the recombinant proteins under the control of AOX1 promoter is a one of the most common expression systems in the methylotrophic yeast Pichia pastoris which is induced by methanol. The application of this expression platform is restricted by the toxicity and inflammatory nature of methanol, especially in food and pharmaceutical products. Human granulocyte macrophage-colony stimulating factor (hGM-CSF) is an important pharmaceutical protein, playing a crucial role in the proliferation and differentiation of innate immune cells. In this study, a methanol-free expression platform for extracellular expression of hGM-CSF was developed. To attain this goal, a novel constructed expression vector pEP(α)101, carrying the FMD promoter regulating recombinant expression by glycerol derepression was designed. The optimized hGM-CSF gene was subcloned into pEP(α)101 and transformed into P. pastoris. The expression of rhGM-CSF in three different culture media were investigated. Based on the observed heterogeneous glycosylation pattern on SDS-PAGE and western blot, the glycoproteins were deglycosylated to remove carbohydrate units. According to the results, the novel methanol independent PFMD expression platform would be a suitable candidate for driving heterologous gene expression especially for the production of food-grade and therapeutically important recombinant proteins.
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Limeres MJ, Gomez ER, Noseda DG, Cerrudo CS, Ghiringhelli PD, Nusblat AD, Cuestas ML. Impact of hepatitis B virus genotype F on in vitro diagnosis: detection efficiency of HBsAg from Amerindian subgenotypes F1b and F4. Arch Virol 2019; 164:2297-2307. [PMID: 31267215 DOI: 10.1007/s00705-019-04332-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 05/31/2019] [Indexed: 02/06/2023]
Abstract
The influence of the high genetic variability of hepatitis B virus (HBV) on the sensitivity of serological assays has received little attention so far. A major source of variability is related to viral genotypes and subgenotypes. Their possible influence on diagnosis and prophylaxis is poorly known and has mostly been evaluated for genotypes A, B, C and D. Robust data showing the detection efficiency of HBsAg from genotype F is lacking. This study examined the effect of virus-like particles containing HBsAg from genotypes A and F (particularly, F1b and F4) produced in Pichia pastoris in relation to the anti-HBs antibodies used in the immunoassays for in vitro diagnosis and compared it with that exerted by the G145R S-escape mutant. The results showed that HBsAg detection rates for subgenotypes F1b and F4 differed significantly from those obtained for genotype A and that subgenotype F1b had a major impact on the sensitivity of the immunoassays tested. Prediction of the tertiary structure of subgenotypes F1b and F4 revealed changes inside and outside the major hydrophilic region (aa 101-160) of the HBsAg compared to genotype A and the G145R variant. A phosphorylation site (target for protein kinase C) produced by the G145R substitution might prevent recognition by anti-HBs antibodies. In conclusion, the use of different genotypes or variants for diagnosis could improve the rate of detection of HBV infection. The incorporation of a genotype-F-derived HBsAg vaccine in areas where this genotype is endemic should be evaluated, since this might also affect vaccination efficacy.
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Affiliation(s)
- María J Limeres
- CONICET, Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Evangelina R Gomez
- Instituto de Agrobiotecnología y Biología Molecular, INTA-CONICET, Buenos Aires, Argentina
| | - Diego G Noseda
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Carolina S Cerrudo
- Departamento de Ciencia y Tecnología, Laboratorio de Ingeniería Genética y Biología Celular y Molecular, Área Virosis de Insectos (LIGBCM-AVI), Instituto de Microbiología Básica y Aplicada (IMBA), Universidad Nacional de Quilmes, Bernal, Provincia de Buenos Aires, Argentina
| | - Pablo D Ghiringhelli
- Departamento de Ciencia y Tecnología, Laboratorio de Ingeniería Genética y Biología Celular y Molecular, Área Virosis de Insectos (LIGBCM-AVI), Instituto de Microbiología Básica y Aplicada (IMBA), Universidad Nacional de Quilmes, Bernal, Provincia de Buenos Aires, Argentina
| | - Alejandro D Nusblat
- Facultad de Farmacia y Bioquímica, Instituto de Nanobiotecnología (NANOBIOTEC), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María L Cuestas
- CONICET, Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM), Universidad de Buenos Aires, Buenos Aires, Argentina.
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Farinha I, Freitas F, Reis MA. Implementation of a repeated fed-batch process for the production of chitin-glucan complex by Komagataella pastoris. N Biotechnol 2017; 37:123-128. [DOI: 10.1016/j.nbt.2016.06.1460] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 05/21/2016] [Accepted: 06/20/2016] [Indexed: 10/21/2022]
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Tran AM, Nguyen TT, Nguyen CT, Huynh-Thi XM, Nguyen CT, Trinh MT, Tran LT, Cartwright SP, Bill RM, Tran-Van H. Pichia pastoris versus Saccharomyces cerevisiae: a case study on the recombinant production of human granulocyte-macrophage colony-stimulating factor. BMC Res Notes 2017; 10:148. [PMID: 28376863 PMCID: PMC5379694 DOI: 10.1186/s13104-017-2471-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 03/27/2017] [Indexed: 11/10/2022] Open
Abstract
Background Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) is a glycoprotein that has been approved by the FDA for the treatment of neutropenia and leukemia in combination with chemotherapies. Recombinant hGM-CSF is produced industrially using the baker’s yeast, Saccharomyces cerevisiae, by large-scale fermentation. The methylotrophic yeast, Pichia pastoris, has emerged as an alternative host cell system due to its shorter and less immunogenic glycosylation pattern together with higher cell density growth and higher secreted protein yield than S. cerevisiae. In this study, we compared the pipeline from gene to recombinant protein in these two yeasts. Results Codon optimization in silico for both yeast species showed no difference in frequent codon usage. However, rhGM-CSF expressed from S. cerevisiae BY4742 showed a significant discrepancy in molecular weight from those of P. pastoris X33. Analysis showed purified rhGM-CSF species with molecular weights ranging from 30 to more than 60 kDa. Fed-batch fermentation over 72 h showed that rhGM-CSF was more highly secreted from P. pastoris than S. cerevisiae (285 and 64 mg total secreted protein/L, respectively). Ion exchange chromatography gave higher purity and recovery than hydrophobic interaction chromatography. Purified rhGM-CSF from P. pastoris was 327 times more potent than rhGM-CSF from S. cerevisiae in terms of proliferative stimulating capacity on the hGM-CSF-dependent cell line, TF-1. Conclusion Our data support a view that the methylotrophic yeast P. pastoris is an effective recombinant host for heterologous rhGM-CSF production. Electronic supplementary material The online version of this article (doi:10.1186/s13104-017-2471-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anh-Minh Tran
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | - Thanh-Thao Nguyen
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | - Cong-Thuan Nguyen
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | - Xuan-Mai Huynh-Thi
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | - Cao-Tri Nguyen
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | - Minh-Thuong Trinh
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | - Linh-Thuoc Tran
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam
| | | | - Roslyn M Bill
- School of Life and Health Sciences, Aston University, Birmingham, UK
| | - Hieu Tran-Van
- Faculty of Biology and Biotechnology, University of Science, VNU-HCM, Ho Chi Minh, Vietnam.
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Jefferis R. Recombinant Proteins and Monoclonal Antibodies. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017; 175:281-318. [DOI: 10.1007/10_2017_32] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Production in stirred-tank bioreactor of recombinant bovine chymosin B by a high-level expression transformant clone of Pichia pastoris. Protein Expr Purif 2016; 123:112-21. [DOI: 10.1016/j.pep.2016.03.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 11/18/2022]
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Looser V, Bruhlmann B, Bumbak F, Stenger C, Costa M, Camattari A, Fotiadis D, Kovar K. Cultivation strategies to enhance productivity of Pichia pastoris: A review. Biotechnol Adv 2015; 33:1177-93. [DOI: 10.1016/j.biotechadv.2015.05.008] [Citation(s) in RCA: 169] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 05/11/2015] [Accepted: 05/25/2015] [Indexed: 12/14/2022]
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Noseda DG, Blasco M, Recúpero M, Galvagno MÁ. Bioprocess and downstream optimization of recombinant bovine chymosin B in Pichia (Komagataella) pastoris under methanol-inducible AOXI promoter. Protein Expr Purif 2014; 104:85-91. [PMID: 25278015 DOI: 10.1016/j.pep.2014.09.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 09/16/2014] [Accepted: 09/19/2014] [Indexed: 11/29/2022]
Abstract
A clone of the methylotrophic yeast Pichia pastoris strain GS115 transformed with the bovine prochymosin B gene was used to optimize the production and downstream of recombinant bovine chymosin expressed under the methanol-inducible AOXI promoter. Cell growth and recombinant chymosin production were analyzed in flask cultures containing basal salts medium with biodiesel-byproduct glycerol as the carbon source, obtaining values of biomass level and milk-clotting activity similar to those achieved with analytical glycerol. The effect of biomass level at the beginning of methanol-induction phase on cell growth and chymosin expression was evaluated, determining that a high concentration of cells at the start of such period generated an increase in the production of chymosin. The impact of the specific growth rate on chymosin expression was studied throughout the induction stage by methanol exponential feeding fermentations in a lab-scale stirred bioreactor, achieving the highest production of heterologous chymosin with a constant specific growth rate of 0.01h(-1). By gel filtration chromatography performed at a semi-preparative scale, recombinant chymosin was purified from exponential fed-batch fermentation cultures, obtaining a specific milk-clotting activity of 6400IMCU/mg of chymosin and a purity level of 95%. The effect of temperature and pH on milk-clotting activity was analyzed, establishing that the optimal temperature and pH values for the purified recombinant chymosin are 37°C and 5.5, respectively. This study reported the features of a sustainable bioprocess for the production of recombinant bovine chymosin in P. pastoris by fermentation in stirred-tank bioreactors using biodiesel-derived glycerol as a low-cost carbon source.
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Affiliation(s)
- Diego Gabriel Noseda
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, 1650, Buenos Aires, Argentina.
| | - Martín Blasco
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, 1650, Buenos Aires, Argentina
| | - Matías Recúpero
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, 1650, Buenos Aires, Argentina
| | - Miguel Ángel Galvagno
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, 1650, Buenos Aires, Argentina; Departamento de Ingeniería Química, Facultad de Ingeniería, Universidad de Buenos Aires, Pabellón de Industrias, Ciudad Universitaria, 1428, Buenos Aires, Argentina
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Cloning, expression and optimized production in a bioreactor of bovine chymosin B in Pichia (Komagataella) pastoris under AOX1 promoter. Protein Expr Purif 2013; 92:235-44. [PMID: 24141135 DOI: 10.1016/j.pep.2013.08.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 07/24/2013] [Accepted: 08/26/2013] [Indexed: 11/21/2022]
Abstract
The codon sequence optimized bovine prochymosin B gene was cloned under the control of the alcohol oxidase 1 promoter (AOX1) in the vector pPIC9K and integrated into the genome of the methylotrophic yeast Pichia (Komagataella) pastoris (P. pastoris) strain GS115. A transformant clone that showed resistance to over 4 mg G418/ml and displayed the highest milk-clotting activity was selected. Cell growth and recombinant bovine chymosin production were optimized in flask cultures during methanol induction phase achieving the highest coagulant activity with low pH values, a temperature of 25°C and with the addition of sorbitol and ascorbic acid at the beginning of this period. The scaling up of the fermentation process to lab-scale stirred bioreactor using optimized conditions, allowed to reach 240 g DCW/L of biomass level and 96 IMCU/ml of milk-clotting activity. The enzyme activity corresponded to 53 mg/L of recombinant bovine chymosin production after 120 h of methanol induction. Western blot analysis of the culture supernatant showed that recombinant chymosin did not suffer degradation during the protein production phase. By a procedure that included high performance gel filtration chromatography and 3 kDa fast ultrafiltration, the recombinant bovine chymosin was purified and concentrated from fermentation cultures, generating a specific activity of 800 IMCU/Total Abs(280 nm) and a total activity recovery of 56%. This study indicated that P. pastoris is a suitable expression system for bioreactor based fed-batch fermentation process for the efficient production of recombinant bovine chymosin under methanol-inducible AOX1 promoter.
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Chien SF. Cloning and Expression of Bioactive Human Granulocyte Colony Stimulating Factor inPichia Pastoris. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.201000118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Mashkani B, Odell AF, Byrnes EM, Griffith R, Ashman LK. Expression of biologically active human colony stimulating factor-1 in Pichia pastoris. Protein Expr Purif 2013; 88:93-7. [DOI: 10.1016/j.pep.2012.11.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 11/15/2012] [Accepted: 11/28/2012] [Indexed: 10/27/2022]
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Zawada JF, Yin G, Steiner AR, Yang J, Naresh A, Roy SM, Gold DS, Heinsohn HG, Murray CJ. Microscale to manufacturing scale-up of cell-free cytokine production--a new approach for shortening protein production development timelines. Biotechnol Bioeng 2011; 108:1570-8. [PMID: 21337337 PMCID: PMC3128707 DOI: 10.1002/bit.23103] [Citation(s) in RCA: 262] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Revised: 01/29/2011] [Accepted: 02/07/2011] [Indexed: 11/12/2022]
Abstract
Engineering robust protein production and purification of correctly folded biotherapeutic proteins in cell-based systems is often challenging due to the requirements for maintaining complex cellular networks for cell viability and the need to develop associated downstream processes that reproducibly yield biopharmaceutical products with high product quality. Here, we present an alternative Escherichia coli-based open cell-free synthesis (OCFS) system that is optimized for predictable high-yield protein synthesis and folding at any scale with straightforward downstream purification processes. We describe how the linear scalability of OCFS allows rapid process optimization of parameters affecting extract activation, gene sequence optimization, and redox folding conditions for disulfide bond formation at microliter scales. Efficient and predictable high-level protein production can then be achieved using batch processes in standard bioreactors. We show how a fully bioactive protein produced by OCFS from optimized frozen extract can be purified directly using a streamlined purification process that yields a biologically active cytokine, human granulocyte-macrophage colony-stimulating factor, produced at titers of 700 mg/L in 10 h. These results represent a milestone for in vitro protein synthesis, with potential for the cGMP production of disulfide-bonded biotherapeutic proteins. Biotechnol. Bioeng. 2011; 108:1570–1578. © 2011 Wiley Periodicals, Inc.
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Affiliation(s)
- James F Zawada
- Sutro Biopharma, Inc. 310 Utah Ave. Suite 150, South San Francisco, California 94080, USA
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Thermococcus kodakarensis as a host for gene expression and protein secretion. Appl Environ Microbiol 2011; 77:2392-8. [PMID: 21278271 DOI: 10.1128/aem.01005-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Taking advantage of the gene manipulation system developed in Thermococcus kodakarensis, here, we developed a system for gene expression and efficient protein secretion using this hyperthermophilic archaeon as a host cell. DNA fragments encoding the C-terminal domain of chitinase (ChiAΔ4), which exhibits endochitinase activity, and the putative signal sequence of a subtilisin-like protease (TK1675) were fused and positioned under the control of the strong constitutive promoter of the cell surface glycoprotein gene. This gene cassette was introduced into T. kodakarensis, and secretion of the ChiAΔ4 protein was examined. ChiAΔ4 was found exclusively in the culture supernatant and was not detected in the soluble and membrane fractions of the cell extract. The signal peptide was specifically cleaved at the C-terminal peptide bond following the Ala-Ser-Ala sequence. Efficient secretion of the orotidine-5'-monophosphate decarboxylase protein was also achieved with the same strategy. We next individually overexpressed two genes (TK1675 and TK1689) encoding proteases with putative signal sequences. By comparing protein degradation activities in the host cells and transformants in both solid and liquid media, as well as measuring peptidase activity using synthetic peptide substrates, we observed dramatic increases in protein degradation activity in the two transformants. This study displays an initial demonstration of cell engineering in hyperthermophiles.
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Lee EG, Park KM, Jeong JY, Lee SH, Baek JE, Lee HW, Jung JK, Chung BH. Carbon nanotube-assisted enhancement of surface plasmon resonance signal. Anal Biochem 2011; 408:206-11. [DOI: 10.1016/j.ab.2010.09.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 08/01/2010] [Accepted: 09/17/2010] [Indexed: 10/19/2022]
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Apte-Deshpande A, Somani S, Mandal G, Soorapaneni S, Padmanabhan S. Over expression and analysis of O-glycosylated recombinant human granulocyte colony stimulating factor in Pichia pastoris using Agilent 2100 Bioanalyzer. J Biotechnol 2009; 143:44-50. [DOI: 10.1016/j.jbiotec.2009.06.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 05/25/2009] [Accepted: 06/04/2009] [Indexed: 11/15/2022]
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