Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
J Struct Funct Genomics
2007 Dec 01;84:153-66. doi: 10.1007/s10969-007-9032-5.
Show Gene links
Show Anatomy links
Small-scale, semi-automated purification of eukaryotic proteins for structure determination.
Frederick RO
,
Bergeman L
,
Blommel PG
,
Bailey LJ
,
McCoy JG
,
Song J
,
Meske L
,
Bingman CA
,
Riters M
,
Dillon NA
,
Kunert J
,
Yoon JW
,
Lim A
,
Cassidy M
,
Bunge J
,
Aceti DJ
,
Primm JG
,
Markley JL
,
Phillips GN
,
Fox BG
.
???displayArticle.abstract???
A simple approach that allows cost-effective automated purification of recombinant proteins in levels sufficient for functional characterization or structural studies is described. Studies with four human stem cell proteins, an engineered version of green fluorescent protein, and other proteins are included. The method combines an expression vector (pVP62K) that provides in vivo cleavage of an initial fusion protein, a factorial designed auto-induction medium that improves the performance of small-scale production, and rapid, automated metal affinity purification of His8-tagged proteins. For initial small-scale production screening, single colony transformants were grown overnight in 0.4 ml of auto-induction medium, produced proteins were purified using the Promega Maxwell 16, and purification results were analyzed by Caliper LC90 capillary electrophoresis. The yield of purified [U-15N]-His8-Tcl-1 was 7.5 microg/ml of culture medium, of purified [U-15N]-His8-GFP was 68 microg/ml, and of purified selenomethione-labeled AIA-GFP (His8 removed by treatment with TEV protease) was 172 microg/ml. The yield information obtained from a successful automated purification from 0.4 ml was used to inform the decision to scale-up for a second meso-scale (10-50 ml) cell growth and automated purification. 1H-15N NMR HSQC spectra of His8-Tcl-1 and of His8-GFP prepared from 50 ml cultures showed excellent chemical shift dispersion, consistent with well folded states in solution suitable for structure determination. Moreover, AIA-GFP obtained by proteolytic removal of the His8 tag was subjected to crystallization screening, and yielded crystals under several conditions. Single crystals were subsequently produced and optimized by the hanging drop method. The structure was solved by molecular replacement at a resolution of 1.7 A. This approach provides an efficient way to carry out several key target screening steps that are essential for successful operation of proteomics pipelines with eukaryotic proteins: examination of total expression, determination of proteolysis of fusion tags, quantification of the yield of purified protein, and suitability for structure determination.
Fig. 1. Expression vector pVP62K. (a) Linear map showing key features of the vector and location of the Bar-CAT toxic cassette and 3â² homology region (3â²-hmr) for Flexi Vector cloning. (b) Nucleotide and encoded protein sequence in the linker region near to the SgfI cloning site. The TVMV protease site is ETVRFQS, where proteolysis occurs between the Q and S residues. The fusion protein may be cleaved in the expression host due to the presence of a low level of TVMV protease produced by constitutive expression from pVP62K. The TEV protease site is ENLYFQA, where proteolysis occurs between the Q and A residues. After purification of the His8-tagged protein, the His8 tag can be removed by treatment with TEV protease to release an N-terminal AIA-target
Fig. 2. Conditional methionine auxotrophy in E. coli B834. (a) Genome organization near to the metE gene in E. coli K12 [51]. (b) Genome organization near to the metE gene in E. coli B834. In this organism, DNA sequencing revealed a large insert in the metE gene, which caused the protein to be truncated to 56 amino acids (aa), non-functional peptide
Fig. 3. Caliper LC90 analysis of His8-tagged proteins purified by Maxwell 16. Lanes LA and LB are molecular weight markers. Lanes A1âB2 are structural genomics target proteins (protein bands marked with ovals) with molecular weight â¼50â75 kDa. They were expressed in factorial evolved auto-induction medium containing selenomethionine [33] as an N-terminal fusion with MBP from pVP56K, a vector that does not give in vivo proteolysis of the fusion protein. Lane B3 contains His8-MBP (protein band marked with oval), while lane B4 (1.1 mg/ml) contains His8-GFP expressed from pVP62 after in vivo cleavage from MBP. Lanes with a purified expressed fusion protein with yield than 100 μg/ml are marked with a star (also see Table 2 )
Fig. 4. Small-scale purification screening of human embryonic stem cell proteins. Human stem cell proteins were expressed in E. coli B834 by auto-induction, liberated by in vivo proteolysis, and purified by the Maxwell 16 purification system. Table 2 provides further information on these proteins. Lane 1, molecular weight markers. Lanes 2 and 3, total cell lysate and eluted sample from purification of CCNF. No purified protein was detected. Lanes 4 and 5, C10orf96 was obtained in detectable amounts, but not sufficient for scale-up, along with two higher molecular weight contaminants. Lanes 6 and 7, His8-Tcl-1 was expressed, proteolyzed, and successfully purified. Lanes 8 and 9, NPM2 was expressed and proteolyzed, but only a small amount of protein was purified. In addition, the purified protein appeared to be partially degraded. Lanes 10 and 11, His8-GFP
Fig. 5. Replicate Maxwell 16 purification of human embryonic stem T-cell lymphoma-1 protein. Lane 1, molecular weight markers. Lanes 2â12, replicate purifications of His8-Tcl-1. Lane 13, His8-MBP-At2g34690.1, an Arabidopsis thaliana protein expression control
Fig. 6. 1Hâ15N HSQC NMR spectra of Maxwell-purified proteins Tcl-1 and GFP. (a) 750 MHz spectrum of His8-Tcl-1 obtained at 35°C (1.75 mg in 250 μl of 10 mM KHPO4, pH 7, containing 50 mM KCl). The total NMR time required to obtain this spectrum was 9.5 h. (b) 600 MHz spectrum of His8-GFP obtained at 35°C (5.6 mg in 250 μl of 10 mM KHPO4, pH 7, containing 50 mM KCl). The total NMR time required to obtain this spectrum was 1 h
Fig. 7. X-ray structure of AIAâGFP. The chromophore is shown as green cylinders representing bonded atoms
Fig. 8. Schematic of a purification screening protocol. Steps from obtaining a sequence-verified target in auto-cleavage vector pVP62K to identification of purified proteins. The transformed expression host is grown in auto-induction medium. Cells from production trials are loaded into the Maxwell 16 instrument for automated purification, and purified proteins are detected by Caliper LC90 capillary electrophoresis. Successful purification of a protein from auto-cleavage expression with yield exceeding 50 μg/ml of culture medium indicates feasibility of scale-up efforts
ARBER,
HOST SPECIFICITY OF DNA PRODUCED BY ESCHERICHIA COLI. 3. EFFECTS ON TRANSDUCTION MEDIATED BY LAMBDA DG.
1964, Pubmed
ARBER,
HOST SPECIFICITY OF DNA PRODUCED BY ESCHERICHIA COLI. 3. EFFECTS ON TRANSDUCTION MEDIATED BY LAMBDA DG.
1964,
Pubmed
Blattner,
The complete genome sequence of Escherichia coli K-12.
1997,
Pubmed
Blommel,
Enhanced bacterial protein expression during auto-induction obtained by alteration of lac repressor dosage and medium composition.
2007,
Pubmed
Blommel,
A combined approach to improving large-scale production of tobacco etch virus protease.
2007,
Pubmed
Blommel,
High efficiency single step production of expression plasmids from cDNA clones using the Flexi Vector cloning system.
2006,
Pubmed
Brenner,
Target selection for structural genomics.
2000,
Pubmed
Brodsky,
Economical parallel protein expression screening and scale-up in Escherichia coli.
2006,
Pubmed
Canaves,
Protein biophysical properties that correlate with crystallization success in Thermotoga maritima: maximum clustering strategy for structural genomics.
2004,
Pubmed
Casimiro,
PCR-based gene synthesis and protein NMR spectroscopy.
1997,
Pubmed
Casimiro,
Gene synthesis, high-level expression, and mutagenesis of Thiobacillus ferrooxidans rusticyanin: His 85 is a ligand to the blue copper center.
1995,
Pubmed
Chayen,
Protein crystallization for genomics: towards high-throughput optimization techniques.
2002,
Pubmed
Collaborative Computational Project, Number 4,
The CCP4 suite: programs for protein crystallography.
1994,
Pubmed
Crameri,
Improved green fluorescent protein by molecular evolution using DNA shuffling.
1996,
Pubmed
Derewenda,
Entropy and surface engineering in protein crystallization.
2006,
Pubmed
Emsley,
Coot: model-building tools for molecular graphics.
2004,
Pubmed
Galvão-Botton,
High-throughput screening of structural proteomics targets using NMR.
2003,
Pubmed
Garrard,
Expression, purification, and crystallization of the RGS-like domain from the Rho nucleotide exchange factor, PDZ-RhoGEF, using the surface entropy reduction approach.
2001,
Pubmed
Goh,
Mining the structural genomics pipeline: identification of protein properties that affect high-throughput experimental analysis.
2004,
Pubmed
Jeon,
High-throughput purification and quality assurance of Arabidopsis thaliana proteins for eukaryotic structural genomics.
2005,
Pubmed
Kato,
Mutational analysis of protein solubility enhancement using short peptide tags.
2007,
Pubmed
Kawasaki,
Random PCR-based screening for soluble domains using green fluorescent protein.
2001,
Pubmed
Kimber,
Data mining crystallization databases: knowledge-based approaches to optimize protein crystal screens.
2003,
Pubmed
King,
Domain structure and protein interactions of the silent information regulator Sir3 revealed by screening a nested deletion library of protein fragments.
2006,
Pubmed
Klein,
Effects of neighboring DNA homopolymers on the biochemical and physical properties of the Escherichia coli lactose promoter. I. Cloning and characterization studies.
1982,
Pubmed
Knaust,
Screening for soluble expression of recombinant proteins in a 96-well format.
2001,
Pubmed
Leahy,
Structure of a fibronectin type III domain from tenascin phased by MAD analysis of the selenomethionyl protein.
1992,
Pubmed
Murshudov,
Refinement of macromolecular structures by the maximum-likelihood method.
1997,
Pubmed
Nguyen,
An automated small-scale protein expression and purification screening provides beneficial information for protein production.
2004,
Pubmed
Page,
Scalable high-throughput micro-expression device for recombinant proteins.
2004,
Pubmed
Patterson,
Use of the green fluorescent protein and its mutants in quantitative fluorescence microscopy.
1997,
Pubmed
Peti,
Towards miniaturization of a structural genomics pipeline using micro-expression and microcoil NMR.
2005,
Pubmed
Prodromou,
Recursive PCR: a novel technique for total gene synthesis.
1992,
Pubmed
Rayment,
Reductive alkylation of lysine residues to alter crystallization properties of proteins.
1997,
Pubmed
Reich,
Combinatorial Domain Hunting: An effective approach for the identification of soluble protein domains adaptable to high-throughput applications.
2006,
Pubmed
Scheich,
Fast identification of folded human protein domains expressed in E. coli suitable for structural analysis.
2004,
Pubmed
Smialowski,
Predicting experimental properties of proteins from sequence by machine learning techniques.
2007,
Pubmed
Smialowski,
Will my protein crystallize? A sequence-based predictor.
2006,
Pubmed
Sreenath,
Protocols for production of selenomethionine-labeled proteins in 2-L polyethylene terephthalate bottles using auto-induction medium.
2005,
Pubmed
Stevens,
Design of high-throughput methods of protein production for structural biology.
2000,
Pubmed
Studier,
Protein production by auto-induction in high density shaking cultures.
2005,
Pubmed
Sugar,
Comparison of small- and large-scale expression of selected Pyrococcus furiosus genes as an aid to high-throughput protein production.
2005,
Pubmed
Thao,
Results from high-throughput DNA cloning of Arabidopsis thaliana target genes using site-specific recombination.
2004,
Pubmed
Tyler,
Auto-induction medium for the production of [U-15N]- and [U-13C, U-15N]-labeled proteins for NMR screening and structure determination.
2005,
Pubmed
Tyler,
Comparison of cell-based and cell-free protocols for producing target proteins from the Arabidopsis thaliana genome for structural studies.
2005,
Pubmed
Vincentelli,
Medium-scale structural genomics: strategies for protein expression and crystallization.
2003,
Pubmed
Watson,
Target selection and determination of function in structural genomics.
2003,
Pubmed
Welch,
Extensive mosaic structure revealed by the complete genome sequence of uropathogenic Escherichia coli.
2002,
Pubmed
Wood,
Host specificity of DNA produced by Escherichia coli: bacterial mutations affecting the restriction and modification of DNA.
1966,
Pubmed
Yang,
Optimized codon usage and chromophore mutations provide enhanced sensitivity with the green fluorescent protein.
1996,
Pubmed
Yee,
NMR and X-ray crystallography, complementary tools in structural proteomics of small proteins.
2005,
Pubmed
Zhou,
A solubility-enhancement tag (SET) for NMR studies of poorly behaving proteins.
2001,
Pubmed