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Thakur KG, Jaiswal RK, Shukla JK, Praveena T, Gopal B. Over-expression and purification strategies for recombinant multi-protein oligomers: a case study of Mycobacterium tuberculosis σ/anti-σ factor protein complexes. Protein Expr Purif 2010; 74:223-30. [PMID: 20600947 DOI: 10.1016/j.pep.2010.06.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/22/2010] [Accepted: 06/23/2010] [Indexed: 01/29/2023]
Abstract
The function of a protein in a cell often involves coordinated interactions with one or several regulatory partners. It is thus imperative to characterize a protein both in isolation as well as in the context of its complex with an interacting partner. High resolution structural information determined by X-ray crystallography and Nuclear Magnetic Resonance offer the best route to characterize protein complexes. These techniques, however, require highly purified and homogenous protein samples at high concentration. This requirement often presents a major hurdle for structural studies. Here we present a strategy based on co-expression and co-purification to obtain recombinant multi-protein complexes in the quantity and concentration range that can enable hitherto intractable structural projects. The feasibility of this strategy was examined using the σ factor/anti-σ factor protein complexes from Mycobacterium tuberculosis. The approach was successful across a wide range of σ factors and their cognate interacting partners. It thus appears likely that the analysis of these complexes based on variations in expression constructs and procedures for the purification and characterization of these recombinant protein samples would be widely applicable for other multi-protein systems.
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52
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Lee CH, Choi DK, Choi HJ, Song MY, Kim YS. Expression of soluble and functional human neonatal Fc receptor in Pichia pastoris. Protein Expr Purif 2010; 71:42-8. [DOI: 10.1016/j.pep.2009.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2009] [Revised: 11/30/2009] [Accepted: 12/07/2009] [Indexed: 12/31/2022]
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Glück JM, Hoffmann S, Koenig BW, Willbold D. Single vector system for efficient N-myristoylation of recombinant proteins in E. coli. PLoS One 2010; 5:e10081. [PMID: 20404920 PMCID: PMC2852408 DOI: 10.1371/journal.pone.0010081] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 03/17/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND N-myristoylation is a crucial covalent modification of numerous eukaryotic and viral proteins that is catalyzed by N-myristoyltransferase (NMT). Prokaryotes are lacking endogenous NMT activity. Recombinant production of N-myristoylated proteins in E. coli cells can be achieved by coexpression of heterologous NMT with the target protein. In the past, dual plasmid systems were used for this purpose. METHODOLOGY/PRINCIPAL FINDINGS Here we describe a single vector system for efficient coexpression of substrate and enzyme suitable for production of co- or posttranslationally modified proteins. The approach was validated using the HIV-1 Nef protein as an example. A simple and efficient protocol for production of highly pure and completely N-myristoylated Nef is presented. The yield is about 20 mg myristoylated Nef per liter growth medium. CONCLUSIONS/SIGNIFICANCE The single vector strategy allows diverse modifications of target proteins recombinantly coexpressed in E. coli with heterologous enzymes. The method is generally applicable and provides large amounts of quantitatively processed target protein that are sufficient for comprehensive biophysical and structural studies.
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Affiliation(s)
- Julian M. Glück
- Institute of Structural Biology and Biophysics, Research Centre Jülich, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Silke Hoffmann
- Institute of Structural Biology and Biophysics, Research Centre Jülich, Jülich, Germany
| | - Bernd W. Koenig
- Institute of Structural Biology and Biophysics, Research Centre Jülich, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Dieter Willbold
- Institute of Structural Biology and Biophysics, Research Centre Jülich, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
- * E-mail:
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54
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Du L, Gao R, Forster AC. Engineering multigene expression in vitro and in vivo with small terminators for T7 RNA polymerase. Biotechnol Bioeng 2010; 104:1189-96. [PMID: 19650080 DOI: 10.1002/bit.22491] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Engineering protein expression in vitro or in vivo is usually straightforward for single genes, but remains challenging for multiple genes because of the requirement of coordinated control. RNA and protein overexpression strategies often exploit T7 RNA polymerase and its natural TPhi Class I terminator. However, this terminator's inefficiency and large size (100 bp) are problematic for multigene construction and expression. Here, we measure the effects of tandem copies of a small (18 bp) Class II T7 terminator from vesicular stomatitis virus on transcription in vitro and on translation in vitro and in vivo. We first test monomeric and dimeric gene constructs, then attempt extension to pentameric gene constructs. "BioBrick" versions of a pET vector and translation factor genes were constructed to facilitate cloning, and His-tags were incorporated to allow copurification of all protein products for relatively unbiased analysis and easy purification. Several results were surprising, including imbalanced expression of the pentameric constructs in vivo, illustrating the value of synthetic biology for investigating gene expression. However, these problems were solved rationally by changing the orders of the genes and by adding extra promoters to the upstream gene or by moving to a more predictable in vitro translation system. These successes were significant, given our initial unexpected results and that we are unaware of another example of coordinated overexpression of five proteins. Our modular, flexible, rational method should further empower synthetic biologists wishing to overexpress multiple proteins simultaneously.
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Affiliation(s)
- Liping Du
- Department of Pharmacology, Vanderbilt Institute of Chemical Biology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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55
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Cheng CY, Yu YJ, Yang MT. Coexpression of ω subunit in E. coli is required for the maintenance of enzymatic activity of Xanthomonas campestris pv. campestris RNA polymerase. Protein Expr Purif 2010; 69:91-8. [DOI: 10.1016/j.pep.2009.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2009] [Revised: 07/01/2009] [Accepted: 07/01/2009] [Indexed: 11/26/2022]
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56
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Zeng J, Zhang L, Li Y, Wang Y, Wang M, Duan X, He ZG. Over-producing soluble protein complex and validating protein–protein interaction through a new bacterial co-expression system. Protein Expr Purif 2010; 69:47-53. [DOI: 10.1016/j.pep.2009.09.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 08/26/2009] [Accepted: 09/04/2009] [Indexed: 02/01/2023]
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57
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Scaife MA, Burja AM, Wright PC. Characterization of cyanobacterial β-carotene ketolase and hydroxylase genes inEscherichia coli, and their application for astaxanthin biosynthesis. Biotechnol Bioeng 2009; 103:944-55. [DOI: 10.1002/bit.22330] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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58
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Karoubi G, Stewart DJ, Courtman DW. A population analysis of VEGF transgene expression and secretion. Biotechnol Bioeng 2008; 101:1083-93. [PMID: 18781692 DOI: 10.1002/bit.21993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The induction of therapeutic angiogenesis with gene therapy approaches has received considerable interest and some limited clinical success. A major drawback to this approach is a lack of understanding of the pharmacokinetics of therapeutic protein delivery. This has become increasingly more relevant as recent studies have illustrated a defined therapeutic window for angiogenic protein secretion into the local microenvironment. For cell based gene therapies, with cells widely distributed throughout the tissue, this implies that any individual cell must attain a specific secretion rate to produce a local angiogenic response. Here we report a reproducible technique enabling the study of growth factor secretion from individual cells following transient plasmid transfection. We demonstrate significant variability in single cell vascular endothelial growth factor (VEGF) secretion with the majority of total protein secretion arising from a small subpopulation of transfected cells. We demonstrate that VEGF secretion is linearly correlated to intracellular plasmid copy number and protein secretion does not appear to reach saturation within the cell population. The selection of gene therapy approaches that optimize individual cell secretion profiles may be essential for the development of effective gene therapies.
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Affiliation(s)
- Golnaz Karoubi
- Division of General Thoracic Surgery, University Hospital Berne, 35 Murtenstrasse, Berne CH3010, Switzerland.
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59
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Miyagi A, Tsunaka Y, Uchihashi T, Mayanagi K, Hirose S, Morikawa K, Ando T. Visualization of Intrinsically Disordered Regions of Proteins by High-Speed Atomic Force Microscopy. Chemphyschem 2008; 9:1859-66. [DOI: 10.1002/cphc.200800210] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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60
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Chen M, Cai L, Fang Z, Tian H, Gao X, Yao W. Site-specific incorporation of unnatural amino acids into urate oxidase in Escherichia coli. Protein Sci 2008; 17:1827-33. [PMID: 18596202 DOI: 10.1110/ps.034587.108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Urate oxidase catalyzes the oxidation of uric acid with poor solubility to produce 5-hydroxyisourate and allantoin. Since allantoin is excreted in vivo, urate oxidase has the potential to be a therapeutic target for the treatment of gout. However, its severe immunogenicity limits its clinical application. Furthermore, studies on the structure-function relationships of urate oxidase have proven difficult. We developed a method for genetically incorporating p-azido-L-phenylalanine into target protein in Escherichia coli in a site-specific manner utilizing a tyrosyl suppressor tRNA/aminoacyl-tRNA synthetase system. We substituted p-azido-L-phenylalanine for Phe(170) or Phe(281) in urate oxidase. The products were purified and their enzyme activities were analyzed. In addition, we optimized the system by adding a "Shine-Dalgarno (SD) sequence" and tandem suppressor tRNA. This method has the benefit of site-specifically modifying urate oxidase with homogeneous glycosyl and PEG derivates, which can provide new insights into structure-function relationships and improve pharmacological properties of urate oxidase.
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Affiliation(s)
- Mingjie Chen
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
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61
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Zweers JC, Barák I, Becher D, Driessen AJ, Hecker M, Kontinen VP, Saller MJ, Vavrová L, van Dijl JM. Towards the development of Bacillus subtilis as a cell factory for membrane proteins and protein complexes. Microb Cell Fact 2008; 7:10. [PMID: 18394159 PMCID: PMC2323362 DOI: 10.1186/1475-2859-7-10] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Accepted: 04/04/2008] [Indexed: 01/16/2023] Open
Abstract
Background The Gram-positive bacterium Bacillus subtilis is an important producer of high quality industrial enzymes and a few eukaryotic proteins. Most of these proteins are secreted into the growth medium, but successful examples of cytoplasmic protein production are also known. Therefore, one may anticipate that the high protein production potential of B. subtilis can be exploited for protein complexes and membrane proteins to facilitate their functional and structural analysis. The high quality of proteins produced with B. subtilis results from the action of cellular quality control systems that efficiently remove misfolded or incompletely synthesized proteins. Paradoxically, cellular quality control systems also represent bottlenecks for the production of various heterologous proteins at significant concentrations. Conclusion While inactivation of quality control systems has the potential to improve protein production yields, this could be achieved at the expense of product quality. Mechanisms underlying degradation of secretory proteins are nowadays well understood and often controllable. It will therefore be a major challenge for future research to identify and modulate quality control systems of B. subtilis that limit the production of high quality protein complexes and membrane proteins, and to enhance those systems that facilitate assembly of these proteins.
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Affiliation(s)
- Jessica C Zweers
- Department of Medical Microbiology, University Medical Center Groningen and University of Groningen, Hanzeplein 1, P,O, Box 30001, 9700 RB Groningen, The Netherlands.
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62
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Zaric BL, Kambach C. Reconstitution of recombinant human LSm complexes for biochemical, biophysical, and cell biological studies. Methods Enzymol 2008; 448:57-74. [PMID: 19111171 DOI: 10.1016/s0076-6879(08)02604-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Sm and Sm-like (LSm) proteins are an ancient family of proteins present in all branches of life. Having originally arisen as RNA chaperones and stabilizers, the family has diversified greatly and fulfills a number of central tasks in various RNA processing events, ranging from pre-mRNA splicing to histone mRNA processing to mRNA degradation. Defects in Sm/LSm protein-containing ribonucleoprotein assembly and function lead to severe medical disorders like spinal muscular atrophy. Sm and LSm proteins always assemble into and function in the form of ringlike hexameric or heptameric complexes whose composition and architecture determine their intracellular location and RNA and effector protein binding specificity and function Sm/LSm complexes that have been assembled in vitro from recombinant components provide a flexible and invaluable tool for detailed cell biological, biochemical, and biophysical studies on these biologically and medically important proteins. We describe here protocols for the construction of bacterial LSm coexpression vectors, expression and purification of LSm proteins and subcomplexes, and the in vitro reconstitution of fully functional human LSm1-7 and LSm2-8 heptameric complexes.
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Affiliation(s)
- Bozidarka L Zaric
- Institut Curie, UMR 7147, Equipe: Recombinaison et Instabilité Génétique, Paris, France
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63
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Scheich C, Kümmel D, Soumailakakis D, Heinemann U, Büssow K. Vectors for co-expression of an unrestricted number of proteins. Nucleic Acids Res 2007; 35:e43. [PMID: 17311810 PMCID: PMC1874614 DOI: 10.1093/nar/gkm067] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A vector system is presented that allows generation of E. coli co-expression clones by a standardized, robust cloning procedure. The number of co-expressed proteins is not limited. Five ‘pQLink’ vectors for expression of His-tag and GST-tag fusion proteins as well as untagged proteins and for cloning by restriction enzymes or Gateway cloning were generated. The vectors allow proteins to be expressed individually; to achieve co-expression, two pQLink plasmids are combined by ligation-independent cloning. pQLink co-expression plasmids can accept an unrestricted number of genes. As an example, the co-expression of a heterotetrameric human transport protein particle (TRAPP) complex from a single plasmid, its isolation and analysis of its stoichiometry are shown. pQLink clones can be used directly for pull-down experiments if the proteins are expressed with different tags. We demonstrate pull-down experiments of human valosin-containing protein (VCP) with fragments of the autocrine motility factor receptor (AMFR). The cloning method avoids PCR or gel isolation of restriction fragments, and a single resistance marker and origin of replication are used, allowing over-expression of rare tRNAs from a second plasmid. It is expected that applications are not restricted to bacteria, but could include co-expression in other hosts such as Bacluovirus/insect cells.
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Affiliation(s)
- Christoph Scheich
- Max Planck Institute for Molecular Genetics, Department of Vertebrate Genomics, Ihnestr. 63-73, 14195 Berlin, Germany, Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany and Free University of Berlin, Institute of Chemistry and Biochemistry, Takustraße 6, 14195 Berlin, Germany
| | - Daniel Kümmel
- Max Planck Institute for Molecular Genetics, Department of Vertebrate Genomics, Ihnestr. 63-73, 14195 Berlin, Germany, Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany and Free University of Berlin, Institute of Chemistry and Biochemistry, Takustraße 6, 14195 Berlin, Germany
| | - Dimitri Soumailakakis
- Max Planck Institute for Molecular Genetics, Department of Vertebrate Genomics, Ihnestr. 63-73, 14195 Berlin, Germany, Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany and Free University of Berlin, Institute of Chemistry and Biochemistry, Takustraße 6, 14195 Berlin, Germany
| | - Udo Heinemann
- Max Planck Institute for Molecular Genetics, Department of Vertebrate Genomics, Ihnestr. 63-73, 14195 Berlin, Germany, Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany and Free University of Berlin, Institute of Chemistry and Biochemistry, Takustraße 6, 14195 Berlin, Germany
| | - Konrad Büssow
- Max Planck Institute for Molecular Genetics, Department of Vertebrate Genomics, Ihnestr. 63-73, 14195 Berlin, Germany, Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany and Free University of Berlin, Institute of Chemistry and Biochemistry, Takustraße 6, 14195 Berlin, Germany
- *To whom correspondence should be addressed. +49 30 9406 2983+49 30 9406 2925
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64
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Stols L, Zhou M, Eschenfeldt WH, Millard CS, Abdullah J, Collart FR, Kim Y, Donnelly MI. New vectors for co-expression of proteins: structure of Bacillus subtilis ScoAB obtained by high-throughput protocols. Protein Expr Purif 2007; 53:396-403. [PMID: 17363272 DOI: 10.1016/j.pep.2007.01.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Revised: 01/17/2007] [Accepted: 01/24/2007] [Indexed: 02/02/2023]
Abstract
The Bacillus subtilis genes scoA and scoB encode subunits of the heteromeric enzyme ScoAB, a putative succinyl-CoA:acetoacetate coenzyme A transferase. High-throughput, ligation-independent cloning (LIC) vectors used extensively for production and purification of single proteins were modified to allow simultaneous expression of interacting proteins and selective purification of functional complexes. Transfer of the LIC region of vector pMCSG7 (L. Stols, M. Gu, L. Dieckman, R. Raffen, F.R. Collart, M.I. Donnelly. A new vector for high-throughput, ligation-independent cloning encoding a tobacco etch virus protease cleavage site. Protein Expr. Purif. (2002) 25, 8-15) into commercial vectors with alternative, compatible origins of replication allowed introduction of standard LIC PCR products into the vectors by uniform protocols. Replacement of the His-tag encoding region of pMCSG7 with a sequence encoding the S-tag enabled selective purification of interacting proteins based on the His-tag associated with one member of the complex. When expressed separately and mixed, the ScoAB subunits failed to interact productively; no transferase activity was detected, and S-tagged ScoB failed to co-purify with His-tagged ScoA. Co-expression, in contrast, generated active transferase that catalyzed the predicted reaction. The ScoAB complex was purified by standard high-throughput metal-ion affinity chromatography procedures, crystallized robotically, and its structure was determined by molecular replacement.
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Affiliation(s)
- Lucy Stols
- Biosciences Division, Argonne National Laboratory, Building 202/Room BE111, 9700 South Cass Avenue, Argonne, IL 60439, USA
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65
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Sugar FJ, Jenney FE, Poole FL, Brereton PS, Izumi M, Shah C, Adams MWW. Comparison of small- and large-scale expression of selected Pyrococcus furiosus genes as an aid to high-throughput protein production. ACTA ACUST UNITED AC 2006; 6:149-58. [PMID: 16211512 DOI: 10.1007/s10969-005-3341-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Accepted: 02/15/2005] [Indexed: 11/28/2022]
Abstract
As the natural extension of the genomic sequencing projects, the goal of the various world-wide Structural Genomics projects is development of techniques for high throughput (HTP) cloning, protein overexpression, purification and structural determination, with the ultimate goal of determining all possible protein structures. Rapid (small-scale) screening of potential expression clones under different growth conditions is presumed to be possible and a viable way to increase throughput of protein expression. In order to test the utility of screening for soluble, heterologous protein expression, we have compared the production of recombinant proteins on a small scale (1 ml cultures in 96-well plates) in Escherichia coli under two growth conditions [a rich medium and a defined (minimal) medium] using an enzyme-linked immunosorbent assay (ELISA) against the affinity tag, with the amount of recombinant protein produced during the large-scale (500 ml) growth of E. coli. The large-scale expression products were examined after a single step affinity purification by visualization on SDS-PAGE gels. Of the open reading frames that were successfully expressed on the 1 ml scale as judged by immunodetection, 80% of them successfully scaled-up to 500 ml in a rich medium and 81% of them scaled-up in a defined medium. This is significantly higher than would be expected by a randomly selected expression condition and validates the use of small-scale expression as a screening tool for more efficient protein production.
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Affiliation(s)
- Frank J Sugar
- Department of Biochemistry and Molecular Biology, Southeastern Collaboratory for Structural Genomics, University of Georgia, Athens, GA 30602, USA
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66
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Jabbour AM, Puryer MA, Yu JY, Lithgow T, Riffkin CD, Ashley DM, Vaux DL, Ekert PG, Hawkins CJ. Human Bcl-2 cannot directly inhibit the Caenorhabditis elegans Apaf-1 homologue CED-4, but can interact with EGL-1. J Cell Sci 2006; 119:2572-82. [PMID: 16735440 DOI: 10.1242/jcs.02985] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although the anti-apoptotic activity of Bcl-2 has been extensively studied, its mode of action is still incompletely understood. In the nematode Caenorhabditis elegans, 131 of 1090 somatic cells undergo programmed cell death during development. Transgenic expression of human Bcl-2 reduced cell death during nematode development, and partially complemented mutation of ced-9, indicating that Bcl-2 can functionally interact with the nematode cell death machinery. Identification of the nematode target(s) of Bcl-2 inhibition would help clarify the mechanism by which Bcl-2 suppresses apoptosis in mammalian cells. Exploiting yeast-based systems and biochemical assays, we analysed the ability of Bcl-2 to interact with and regulate the activity of nematode apoptosis proteins. Unlike CED-9, Bcl-2 could not directly associate with the caspase-activating adaptor protein CED-4, nor could it inhibit CED-4-dependent yeast death. By contrast, Bcl-2 could bind the C. elegans pro-apoptotic BH3-only Bcl-2 family member EGL-1. These data prompt us to hypothesise that Bcl-2 might suppress nematode cell death by preventing EGL-1 from antagonising CED-9, rather than by inhibiting CED-4.
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Affiliation(s)
- Anissa M Jabbour
- Children's Cancer Centre, Royal Children's Hospital, Parkville 3052, Australia
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67
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Abstract
Much of systems biology aims to predict the behaviour of biological systems on the basis of the set of molecules involved. Understanding the interactions between these molecules is therefore crucial to such efforts. Although many thousands of interactions are known, precise molecular details are available for only a tiny fraction of them. The difficulties that are involved in experimentally determining atomic structures for interacting proteins make predictive methods essential for progress. Structural details can ultimately turn abstract system representations into models that more accurately reflect biological reality.
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Affiliation(s)
- Patrick Aloy
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
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68
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Graumann K, Premstaller A. Manufacturing of recombinant therapeutic proteins in microbial systems. Biotechnol J 2006; 1:164-86. [PMID: 16892246 DOI: 10.1002/biot.200500051] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Recombinant therapeutic proteins have gained enormous importance for clinical applications. The first recombinant products have been produced in E. coli more than 20 years ago. Although with the advent of antibody-based therapeutics mammalian expression systems have experienced a major boost, microbial expression systems continue to be widely used in industry. Their intrinsic advantages, such as rapid growth, high yields and ease of manipulation, make them the premier choice for expression of non-glycosylated peptides and proteins. Innovative product classes such as antibody fragments or alternative binding molecules will further expand the use of microbial systems. Even more, novel, engineered production hosts and integrated technology platforms hold enormous potential for future applications. This review summarizes current applications and trends for development, production and analytical characterization of recombinant therapeutic proteins in microbial systems.
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Affiliation(s)
- Klaus Graumann
- Novartis Biopharmaceutical Operations, Sandoz GmbH, Biochemiestrasse 10, 6250 Kundl, Austria.
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69
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Fairlie WD, Perugini MA, Kvansakul M, Chen L, Huang DCS, Colman PM. CED-4 forms a 2 : 2 heterotetrameric complex with CED-9 until specifically displaced by EGL-1 or CED-13. Cell Death Differ 2005; 13:426-34. [PMID: 16167070 DOI: 10.1038/sj.cdd.4401762] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The pathway to cell death in Caenorhabditis elegans is well established. In cells undergoing apoptosis, the Bcl-2 homology domain 3 (BH3)-only protein EGL-1 binds to CED-9 at the mitochondrial membrane to cause the release of CED-4, which oligomerises and facilitates the activation of the caspase CED-3. However, despite many studies, the biophysical features of the CED-4/CED-9 complex have not been fully characterised. Here, we report the purification of a soluble and stable 2 : 2 heterotetrameric complex formed by recombinant CED-4 and CED-9 coexpressed in bacteria. Consistent with previous studies, synthetic peptides corresponding to the BH3 domains of worm BH3-only proteins (EGL-1, CED-13) dissociate CED-4 from CED-9, but not from the gain-of-function CED-9 (G169E) mutant. Surprisingly, the ability of worm BH3 domains to dissociate CED-4 was specific since mammalian BH3-only proteins could not do so.
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Affiliation(s)
- W D Fairlie
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
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70
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Hunt I. From gene to protein: a review of new and enabling technologies for multi-parallel protein expression. Protein Expr Purif 2005; 40:1-22. [PMID: 15721767 DOI: 10.1016/j.pep.2004.10.018] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2004] [Revised: 10/07/2004] [Indexed: 10/26/2022]
Abstract
In the post-genomic era, increasingly greater demands and expectations are being placed on protein production laboratories to produce more proteins and in faster timelines. This has been coupled with an exponential increase in the number of requests for the production of proteins which lack structural and functional information. No longer can groups use literature available in the public domain solely to drive their expression strategy, and moreover current expression and concomitant purification strategies clearly do not meet modern-day demands for protein production. This review will therefore attempt to provide a definitive review of current 'best in class' cloning, expression and purification systems, and the adaptations and developments that have been made by laboratories, both academic and industrial, to enhance protein production throughput.
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Affiliation(s)
- Ian Hunt
- Novartis Horsham Research Centre, Novartis Institutes for Biomedical Research, Wimblehurst Road, Horsham, West Sussex, UK.
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