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Protein Expression and Purification

Jennifer Konczal, Christopher H Gray
Protein production facilities are often required to produce diverse arrays of proteins for demanding methodologies including crystallography, NMR, ITC and other reagent intensive techniques. It is common for these teams to find themselves a bottleneck in the pipeline of ambitious projects. This pressure to deliver has resulted in the evolution of many novel methods to increase capacity and throughput at all stages in the pipeline for generation of recombinant proteins. This review aims to describe current and emerging options to accelerate the success of protein production in Escherichia coli...
March 18, 2017: Protein Expression and Purification
Agnes Papala, Marc Sylvester, Nadine Dyballa-Rukes, Sabine Metzger, Jochen D'Haese
CapG is an actin-binding protein, which is overexpressed in a variety of tumors, i.e. breast, ovarian, pancreatic and lung carcinoma. We successfully expressed human CapG in the wild type strain X-33 of the methylotrophic yeast Pichia pastoris (P. pastoris), which does not express endogenous CapG, in order to characterize this protein in more detail. After mechanical cell lysis, debris was centrifuged and the soluble protein was precipitated with ammonium sulfate. This protein pellet was dialyzed and used for CapG purification...
March 18, 2017: Protein Expression and Purification
Qi Wang, Yongdong Liu, Chun Zhang, Fangxia Guo, Cui Feng, Xiunan Li, Hong Shi, Zhiguo Su
Protein refolding from inclusion bodies (IBs) often encounters a problem of low recovery at high protein concentration. In this study, we demonstrated that high hydrostatic pressure (HHP) could simultaneously achieve high refolding concentration and high refolding yield for IBs of recombinant human ciliary neurotrophic factor (rhCNTF), a potential therapeutic for neurodegenerative diseases. The use of dilution refolding obtained 18% recovery at 3 mg/mL, even in the presence of 4 M urea. In contrast, HHP refolding could efficiently increase the recovery up to almost 100% even at 4 mg/mL...
March 18, 2017: Protein Expression and Purification
Omar Herrera-Asmat, Lucyna Lubkowska, Mikhail Kashlev, Carlos J Bustamante, Daniel G Guerra, Maria L Kireeva
Recent publications have shown that active RNA polymerase (RNAP) from Mycobacterium tuberculosis (MtbRNAP) can be produced by expressing all four subunits in a single recombinant Escherichia coli strain [1-3]. By reducing the number of plasmids and changing the codon usage of the Mtb genes in the co-expression system published by Banerjee et al. [1], we present a simplified, detailed and reproducible protocol for the purification of recombinant MtbRNAP containing the ω subunit. Moreover, we describe the formation of ternary elongation complexes (TECs) with a short fluorescence-labeled RNA primer and DNA oligonucleotides, suitable for transcription elongation studies...
March 17, 2017: Protein Expression and Purification
Mahboobeh Nazari, Amir-Hassan Zarnani, Roya Ghods, Rahman Emamzadeh, Somayeh Najafzadeh, Arash Minai-Tehrani, Jafar Mahmoudian, Maryam Yousefi, Sedigheh Vafaei, Sam Massahi, Mohammad-Reza Nejadmoghaddam
Placenta specific -1 (PLAC1) has been recently introduced as a small membrane-associated protein mainly involved in placental development. Expression of PLAC1 transcript has been documented in almost one hundred cancer cell lines standing for fourteen distinct cancer types. The presence of two disulfide bridges makes difficult to produce functional recombinant PLAC1 in soluble form with high yield. This limitation also complicates the structural studies of PLAC1, which is important for prediction of its physiological roles...
March 16, 2017: Protein Expression and Purification
Xuguang Chen, Alireza Nomani, Niket Patel, Arash Hatefi
The growing complexity of recombinant biopolymers for delivery of bioactive agents requires the ability to control the biomaterial structure with high degree of precision. Genetic engineering techniques have provided this opportunity to synthesize biomaterials in an organism such as E. coli with full control over their lengths and sequences. One class of such biopolymers is recombinant cationic biopolymers with applications in gene delivery, regenerative medicine and variety of other biomedical applications...
March 15, 2017: Protein Expression and Purification
Xinrui Zhao, Haofei Hong, Zhimeng Wu
In order to achieve efficient extracellular expression of Sortase A (SrtA), various strategies in Pichia pastoris system were applied in this study. Among different constructed recombinant strains, the SMD1168 strain integrated 5.7 copies of srtA gene under control of AOX1 promoter was proved to be the best strain for the extracellular SrtA expression. After the optimization of fermentation conditions (induction 72 h at 28 °C, initial pH 6.0, supplemented with 1.5% methanol), the highest yield and activity of extracellular SrtA reached 97...
March 15, 2017: Protein Expression and Purification
Hsin-Yang Chang, Chia-Cheng Chou, Mao-Lun Wu, Andrew H J Wang
Undecaprenyl pyrophosphate phosphatase (UppP), a cell membrane integral enzyme, catalyzes the dephosphorylation of undecaprenyl pyrophosphate to undecaprenyl phosphate, which is an essential carrier lipid in bacterial cell wall synthesis. We previously purified E. coli UppP and concluded that its catalytic site is likely located in the periplasm. To search for additional natural UppP homologs to elucidate what constitutes a common catalytic mechanism and to gain a better chance of obtaining high-resolution crystal structural information, we expressed and purified recombinant Vibrio vulnificus UppP using E...
March 14, 2017: Protein Expression and Purification
Yasuo Mitani, Yoshimi Oshima, Nobutaka Mitsuda, Azusa Tomioka, Masako Sukegawa, Mika Fujita, Hiroyuki Kaji, Yoshihiro Ohmiya
Cypridina noctiluca luciferase has been utilized for biochemical and molecular biological applications, including bioluminescent enzyme immunoassays, far-red luminescence imaging, and high-throughput reporter assays. Some of these applications require a large amount of purified luciferase. However, conventional protein expression systems are not capable of producing sufficient quantities of protein with a high quality and purity without laborious and costly purification processes. To improve the productivity and expand the breadth of possibilities for Cypridina luciferase applications, we employed a variety of secretion expression systems, including yeast, mammalian cells, and silk worms...
March 11, 2017: Protein Expression and Purification
Yuanyuan Dong, Li Jian, Na Yao, Dezhong Wang, Xiuming Liu, Nan Wang, Xiaowei Li, Fawei Wang, Haiyan Li, Chao Jiang
Antibodies to human epidermal growth factor receptor 2 (HER2) are a key element of breast cancer therapy; however, they are expensive to produce and their availability is limited. A seed-specific expression system can be used to produce recombinant proteins. We report a seed-specific expression system for the manufacture of anti-HER2 ScFv-Fc in Arabidopsis thaliana, driven by the Phaseolus vulgaris β-phaseolin promoter. Recombinant anti-HER2 ScFv-Fc was successfully and specifically expressed in seeds, and identified by protein analysis...
March 9, 2017: Protein Expression and Purification
Graham C Robinson, Yogesh Vegunta, Caroline Gabus, Christl Gaubitz, Stéphane Thore
The Target of Rapamycin Complex is a central controller of cell growth and differentiation in eukaryotes. Its global architecture has been described by cryoelectron microscopy, and regions of its central TOR protein have been described by X-ray crystallography. However, the N-terminal region of this protein, which consists of a series of HEAT repeats, remains uncharacterised at high resolution, most likely due to the absence of a suitable purification procedure. Here, we present a robust method for the preparation of the HEAT-repeat domain, utilizing the thermophilic fungus Chaetomium thermophilum as a source organism...
March 8, 2017: Protein Expression and Purification
Shan Lin, Zhi-Qiang Liu, Ming Yi, Hui Wu, Feng Xu, Yu-Guo Zheng
Two novel family 18 chitinases, chiA and chiH, were identified and cloned from the transcriptome of H. sinensis based on the transcriptome sequence data. The recombinant chitinases were overexpressed in Escherichia coli BL21, subsequently purified and functionally characterized. The optimal temperature and pH for chiA were 55 °C and 5.0, respectively, and those for chiH were 50 °C and 5.0, respectively. The highest enzyme activities of 11.5 U/mg and 8.1 U/mg were obtained for chiA and chiH, respectively, when colloidal chitin was used as the substrate with Ba(2+)...
March 6, 2017: Protein Expression and Purification
Benjamin W Elberson, Ty E Whisenant, D Marien Cortes, Luis G Cuello
The Erwinia chrisanthemi ligand-gated ion channel, ELIC, is considered an excellent structural and functional surrogate for the whole pentameric ligand-gated ion channel family. Despite its simplicity, ELIC is structurally capable of undergoing ligand-dependent activation and a concomitant desensitization process. To determine at the molecular level the structural changes underlying ELIC's function, it is desirable to produce large quantities of protein. This protein should be properly folded, fully-functional and amenable to structural determinations...
March 6, 2017: Protein Expression and Purification
Maxime Combe, Xavier Lacoux, Jérôme Martinez, Odile Méjan, Françoise Luciani, Soizic Daniel
Dengue is a mosquito-borne disease caused by four genetically and serologically related viruses that affect several millions of people. Envelope domain III (EDIII) of the viral envelope protein contains dengue virus (DENV) type-specific and DENV complex-reactive antigenic sites. Here, we describe the expression in Escherichia coli, the refolding and bio-structural analysis of envelope domain III of the four dengue serotypes as a tetravalent dengue protein (EDIIIT2), generating an attractive diagnostic candidate...
March 6, 2017: Protein Expression and Purification
Daning Wang, Fei Fan, Zhihai Li, Xinlin Liu, Shuo Song, Shuangping Wei, Maozhou He, Yahua Lin, Zhongyi Li, Minxi Wei, Hai Yu, Ying Gu, Shaowei Li, Ningshao Xia
Human papillomavirus (HPV) is widely accepted to be the major causative pathogen of cervical cancer, warts, and other epithelial tumors. Virus infection and subsequent disease development can be prevented by vaccination with HPV vaccines derived from eukaryotic expression systems. Here, we report the soluble expression of the major capsid protein L1 of HPV31, a dominant carcinogenic HPV genotype, in Escherichia coli. HPV31 L1 protein and its elongated form (L1+) were observed in SDS-PAGE and CE-SDS analysis, generated by the native HPV31 L1 gene with a TAA stop codon...
March 4, 2017: Protein Expression and Purification
Thao T Ho, Jasmine T Nguyen, Juping Liu, Pawel Stanczak, Aaron A Thompson, Yingzhuo G Yan, Jasmine Chen, Charles K Allerston, Charles L Dillard, Hao Xu, Nicholas J Shoger, Jill S Cameron, Mark E Massari, Kathleen Aertgeerts
Recent innovative approaches to stabilize and crystallize GPCRs have resulted in an unprecedented breakthrough in GPCR crystal structures as well as application of the purified receptor protein in biophysical and biochemical ligand binding assays. However, the protein optimization process to enable these technologies is lengthy and requires iterative overexpression, solubilization, purification and functional analysis of tens to hundreds of protein variants. Here, we report a new and versatile method to screen in parallel hundreds of GPCR variants in HEK293 produced virus-like particles (VLPs) for protein yield, stability, functionality and ligand binding...
March 3, 2017: Protein Expression and Purification
Abolfazl Mirzadeh, Geita Saadatnia, Majid Golkar, Jalal Babaie, Rahmah Noordin
SAG1-related sequence 3 (SRS3) is one of the major Toxoplasma gondii tachyzoite surface antigens and has been shown to be potentially useful for the detection of toxoplasmosis. This protein is highly conformational due to the presence of six disulfide bonds. To achieve solubility and antigenicity, SRS3 depends on proper disulfide bond formation. The aim of this study was to over-express the SRS3 protein with correct folding for use in serodiagnosis of the disease. To achieve this, a truncated SRS3 fusion protein (rtSRS3) was produced, containing six histidyl residues at both terminals and purified by immobilized metal affinity chromatography...
March 2, 2017: Protein Expression and Purification
Margarita Rashev, Jennifer A Surtees, Alba Guarné
Saccharomyces cerevisiae Saw1 is an essential gene in single-strand annealing - the DNA repair pathway that repairs double-strand breaks when they occur between homologous repeats. Saw1 interacts with the structure-specific nuclease Rad1-Rad10 and this results in the recruitment of this nuclease to 3' non-homologous DNA tailed recombination intermediates. Saw1 is unstable in the absence of the Rad1-Rad10 nuclease and, hence, it has been difficult to study its specific function in vitro. In the present work, we present the combination of dynamic light scattering and differential scanning fluorimetry techniques to optimize the stability and homogeneity of recombinant Saw1...
March 2, 2017: Protein Expression and Purification
Jakub Gabrielczyk, Hans-Joachim Jördening
The most significant drawback of bacterial protein production involving inclusion bodies is the subsequent refolding into bioactive form. Implementation of refolding operations in large-scale applications often fails due to low yields and/or low product concentrations. This paper presents a simple method of integrated refolding by dialysis and matrix assisted refolding that combines advantages of both methods, high product concentrations and high refolding yields. Ion exchange resins (IER) and size exclusion media served as refolding additives and were added to solubilized protein prior to refolding by continuous exchange of dialysis buffer...
March 1, 2017: Protein Expression and Purification
Naruhiko Adachi, Kyohei Aizawa, Yuka Kratzer, Shinya Saijo, Nobutaka Shimizu, Toshiya Senda
In vitro transcription systems have been utilized to elucidate detailed mechanisms of transcription. Purified RNA polymerase II (pol II) and general transcription factors (GTFs) are required for the in vitro reconstitution of eukaryotic transcription systems. Among GTFs, TFIID and TFIIA play critical roles in the early stage of transcription initiation; TFIID first binds to the DNA in transcription initiation and TFIIA regulates TFIID's DNA binding activity. Despite the important roles of TFIIA, the time-consuming steps required to purify it, such as denaturing and refolding, have hampered the preparation of in vitro transcription systems...
March 1, 2017: Protein Expression and Purification
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