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Liu TT, Huang SH, Chao L. Rapid Enrichment of a Native Multipass Transmembrane Protein via Cell Membrane Electrophoresis through Buffer pH and Ionic Strength Adjustment. J Am Chem Soc 2024; 146:11634-11647. [PMID: 38628144 PMCID: PMC11066866 DOI: 10.1021/jacs.3c13579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024]
Abstract
Supported membrane electrophoresis is a promising technique for collecting membrane proteins in native bilayer environments. However, the slow mobility of typical transmembrane proteins has impeded the technique's advancement. Here, we successfully applied cell membrane electrophoresis to rapidly enrich a 12-transmembrane helix protein, glucose transporter 1 with antibodies (GLUT1 complex), by tuning the buffer pH and ionic strength. The identified conditions allowed the separation of the GLUT1 complex and a lipid probe, Fast-DiO, within a native-like environment in a few minutes. A force model was developed to account for distinct electric and drag forces acting on the transmembrane and aqueous-exposed portion of a transmembrane protein as well as the electroosmotic force. This model not only elucidates the impact of size and charge properties of transmembrane proteins but also highlights the influence of pH and ionic strength on the driving forces and, consequently, electrophoretic mobility. Model predictions align well with experimentally measured electrophoretic mobilities of the GLUT1 complex and Fast-DiO at various pH and ionic strengths as well as with several lipid probes, lipid-anchored proteins, and reconstituted membrane proteins from previous studies. Force analyses revealed the substantial membrane drag of the GLUT1 complex, significantly slowing down electrophoretic mobility. Besides, the counterbalance of similar magnitudes of electroosmotic and electric forces results in a small net driving force and, consequently, reduced mobility under typical neutral pH conditions. Our results further highlight how the size and charge properties of transmembrane proteins influence the suitable range of operating conditions for effective movement, providing potential applications for concentrating and isolating membrane proteins within this platform.
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Affiliation(s)
- Tzu-Tzu Liu
- Department of Chemical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Sin-Han Huang
- Department of Chemical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Ling Chao
- Department of Chemical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
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2
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Wang X, Cui D, Qu X, You H, Lei F, Li J, Xie Y, Zhang H, Zhang Y, Jiang S, Xie Q. Analytical Ultracentrifugation-Calibrated Anion-Exchange Chromatography for Sensitive and Intact Determination of Osteopontin in Infant Formula and Dairy Products. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:13880-13888. [PMID: 37669461 PMCID: PMC10515612 DOI: 10.1021/acs.jafc.3c03589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/26/2023] [Accepted: 08/28/2023] [Indexed: 09/07/2023]
Abstract
Osteopontin is a crucial protein ingredient that has been applied in fortified dairy products and infant formula. It has great significance to infant gut health and brain development. However, current techniques including enzyme-linked immunosorbent assay and liquid chromatography coupled with mass spectrometry are still facing the bottleneck of low sensitivity and indirect quantification. Moreover, the unavailable certified commercial OPN standard hinders its accurate quantification. Herein, a novel method of anion-exchange chromatography was established to determine OPN concentration in several dairy matrices. The polarity-reversed capillary isoelectric focusing was utilized to measure the exact isoelectric point (pI) to support method development for OPN separation. Analytical ultracentrifugation was used to calibrate the purity of intact OPN to develop an in-house reference standard. The method showed the merits of limits of detection to 0.04 mg/100 g, relative standard deviation of reproducibility <5% for 13 out of 14 tested matrices, and an average recovery rate of 101.3%. This method has shown the potential to be adopted as an international standard method for the quantification of intact OPN in infant formula and dairy products.
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Affiliation(s)
- Xiangxin Wang
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Dongying Cui
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Xueyin Qu
- China
Excellent Milk Academy (Tianjin) Co., Ltd., 300400 Tianjin, China
| | - Hong You
- Eurofins
US Food, 2200 Rittenhouse
St Ste 175, Des Moines, Iowa 50321-3155, United
States
| | - Fan Lei
- State
Key Laboratory of Membrane Biology, Tsinghua
University, Beijing 100084, China
| | - Jianqiao Li
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Yang Xie
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Haoshu Zhang
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Yongjiu Zhang
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Shilong Jiang
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
| | - Qinggang Xie
- Heilongjiang
Feihe Dairy Co., Ltd., Beijing 100015, China
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3
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Wasilko DJ, Johnson ZL, Ammirati M, Che Y, Griffor MC, Han S, Wu H. Structural basis for chemokine receptor CCR6 activation by the endogenous protein ligand CCL20. Nat Commun 2020; 11:3031. [PMID: 32541785 PMCID: PMC7295996 DOI: 10.1038/s41467-020-16820-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 05/27/2020] [Indexed: 01/08/2023] Open
Abstract
Chemokines are important protein-signaling molecules that regulate various immune responses by activating chemokine receptors which belong to the G protein-coupled receptor (GPCR) superfamily. Despite the substantial progression of our structural understanding of GPCR activation by small molecule and peptide agonists, the molecular mechanism of GPCR activation by protein agonists remains unclear. Here, we present a 3.3-Å cryo-electron microscopy structure of the human chemokine receptor CCR6 bound to its endogenous ligand CCL20 and an engineered Go. CCL20 binds in a shallow extracellular pocket, making limited contact with the core 7-transmembrane (TM) bundle. The structure suggests that this mode of binding induces allosterically a rearrangement of a noncanonical toggle switch and the opening of the intracellular crevice for G protein coupling. Our results demonstrate that GPCR activation by a protein agonist does not always require substantial interactions between ligand and the 7TM core region. Chemokine receptors are GPCRs involved in immune responses and regulated by small protein ligands known as chemokines. A structural study of the human CCR6/CCL20–Go complex reveals that CCL20 binds in a shallow extracellular pocket, and suggests that activation of CCR6 by CCL20 binding involves an allosteric effect on a noncanonical toggle switch.
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Affiliation(s)
- David Jonathan Wasilko
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA
| | - Zachary Lee Johnson
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA
| | - Mark Ammirati
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA
| | - Ye Che
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA
| | - Matthew C Griffor
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA
| | - Seungil Han
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA
| | - Huixian Wu
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research and Development, Groton, CT, 06340, USA.
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4
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Tovar G. Design of a software for calculating isoelectric point of a polypeptide according to their net charge using the graphical programming language LabVIEW. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 46:39-46. [PMID: 29105959 DOI: 10.1002/bmb.21088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 06/23/2017] [Accepted: 10/06/2017] [Indexed: 06/07/2023]
Abstract
A software to calculate the net charge and to predict the isoelectric point (pI) of a polypeptide is developed in this work using the graphical programming language LabVIEW. Through this instrument the net charges of the ionizable residues of the polypeptide chains of the proteins are calculated at different pH values, tabulated, pI is predicted and an Excel (-xls) type file is generated. In this work, the experimental values of the pIs (pI) of different proteins are compared with the values of the pIs (pI) calculated graphically, achieving a correlation coefficient (R) of 0.934746 which represents a good reliability for a p < 0.01. In this way the generated program can constitute an instrument applicable in the laboratory, facilitating the calculation to graduate students and junior researchers. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(1):39-46, 2018.
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Affiliation(s)
- Glomen Tovar
- Instituto de Investigaciones Biomédicas (BIOMED), Universidad de Carabobo, Núcleo Aragua, Las Delicias Maracay, Venezuela 2101
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5
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Danish MK, Vozza G, Byrne HJ, Frias JM, Ryan SM. Formulation, Characterization and Stability Assessment of a Food-Derived Tripeptide, Leucine-Lysine-Proline Loaded Chitosan Nanoparticles. J Food Sci 2017; 82:2094-2104. [PMID: 28796309 DOI: 10.1111/1750-3841.13824] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/19/2017] [Accepted: 06/28/2017] [Indexed: 01/19/2023]
Abstract
The chicken- or fish-derived tripeptide, leucine-lysine-proline (LKP), inhibits the angiotensin converting enzyme and may be used as an alternative treatment for prehypertension. However, it has low permeation across the small intestine. The formulation of LKP into a nanoparticle (NP) has the potential to address this issue. LKP-loaded NPs were produced using an ionotropic gelation technique, using chitosan (CL113). Following optimization of unloaded NPs, a mixture amount design was constructed using variable concentration of CL113 and tripolyphosphate at a fixed LKP concentration. Resultant particle sizes ranged from 120 to 271 nm, zeta potential values from 29 to 37 mV, and polydispersity values from 0.3 to 0.6. A ratio of 6:1 (CL113:TPP) produced the best encapsulation of approximately 65%. Accelerated studies of the loaded NPs indicated stability under normal storage conditions (room temperature). Cytotoxicity assessment showed no significant loss of cell viability and in vitro release studies indicated an initial burst followed by a slower and sustained release.
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Affiliation(s)
- Minna K Danish
- School of Food Science and Environmental Health, Dublin Inst. of Technology, Marlborough St., Dublin 1, Ireland.,FOCAS Research Inst., Dublin Inst. of Technology, Kevin St., Dublin 8, Ireland
| | - Giuliana Vozza
- School of Food Science and Environmental Health, Dublin Inst. of Technology, Marlborough St., Dublin 1, Ireland.,FOCAS Research Inst., Dublin Inst. of Technology, Kevin St., Dublin 8, Ireland
| | - Hugh J Byrne
- FOCAS Research Inst., Dublin Inst. of Technology, Kevin St., Dublin 8, Ireland
| | - Jesus M Frias
- School of Food Science and Environmental Health, Dublin Inst. of Technology, Marlborough St., Dublin 1, Ireland.,Environmental Sustainability and Health Institute, Dublin Inst. of Technology. Grangegorman, Dublin 7, Ireland
| | - Sinéad M Ryan
- School of Veterinary Medicine, Univ. College Dublin, Belfield, Dublin 4, Ireland
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6
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Dietrich MA, Słowińska M, Karol H, Adamek M, Steinhagen D, Hejmej A, Bilińska B, Ciereszko A. Serine protease inhibitor Kazal-type 2 is expressed in the male reproductive tract of carp with a possible role in antimicrobial protection. FISH & SHELLFISH IMMUNOLOGY 2017; 60:150-163. [PMID: 27867114 DOI: 10.1016/j.fsi.2016.11.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 11/09/2016] [Accepted: 11/14/2016] [Indexed: 06/06/2023]
Abstract
The presence of the low-molecular-mass serine protease inhibitor Kazal-type (Spink) is a characteristic feature of vertebrate semen. Its main function is control of the serine protease in the acrosome, acrosin. Here we showed for the first time that Spink is present in the seminal plasma of carp, which have anacrosomal spermatozoa. Using a three-step isolation procedure that consisted in gel filtration and RP-HPLC and re-RP-HPLC, we isolated this inhibitor and identified it as serine protease inhibitor Kazal-type 2 (Spink2), a reproductive-derived member of the Spink family. The cDNA sequence of this inhibitor obtained from carp testis encoded 77 amino acids, including a 17 amino acids signal peptide; this sequence was distinct from fish Kazal-type inhibitors. The mRNA expression analysis showed that Spink2 is expressed predominantly in carp testis and spermatic duct. Immunohistochemical analysis demonstrated its localization in testis in Sertoli, Leydig and germ cells at all developmental stages (with the exception of spermatozoa) and in the epithelium of the spermatic duct. Aside from strong inhibition of trypsin, this inhibitor acts strongly against subtilisin and possesses bacteriostatic activities against Lactobacillus subtilis, Escherichia coli and Aeromonas hydrophila. The localization of Spink2 in carp reproductive tract suggests an important function in spermatogenesis and in maintenance of the microenvironment in which sperm maturation occurs and sperm are stored. Our results suggest that Spink2 from carp seminal plasma may play a role in antibacterial semen defense, protecting semen against unwanted proteolysis within the reproductive tract.
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Affiliation(s)
- Mariola A Dietrich
- Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland.
| | - Mariola Słowińska
- Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland
| | - Halina Karol
- Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland
| | - Mikołaj Adamek
- Fish Disease Research Unit, University of Veterinary Medicine in Hanover, 30559 Hannover, Germany
| | - Dieter Steinhagen
- Fish Disease Research Unit, University of Veterinary Medicine in Hanover, 30559 Hannover, Germany
| | - Anna Hejmej
- Department of Endocrinology, Institute of Zoology, Jagiellonian University, 30-387 Krakow, Poland
| | - Barbara Bilińska
- Department of Endocrinology, Institute of Zoology, Jagiellonian University, 30-387 Krakow, Poland
| | - Andrzej Ciereszko
- Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland
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7
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Audain E, Ramos Y, Hermjakob H, Flower DR, Perez-Riverol Y. Accurate estimation of isoelectric point of protein and peptide based on amino acid sequences. ACTA ACUST UNITED AC 2015; 32:821-7. [PMID: 26568629 PMCID: PMC5939969 DOI: 10.1093/bioinformatics/btv674] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 11/10/2015] [Indexed: 12/02/2022]
Abstract
Motivation: In any macromolecular polyprotic system—for example protein, DNA or RNA—the isoelectric point—commonly referred to as the pI—can be defined as the point of singularity in a titration curve, corresponding to the solution pH value at which the net overall surface charge—and thus the electrophoretic mobility—of the ampholyte sums to zero. Different modern analytical biochemistry and proteomics methods depend on the isoelectric point as a principal feature for protein and peptide characterization. Protein separation by isoelectric point is a critical part of 2-D gel electrophoresis, a key precursor of proteomics, where discrete spots can be digested in-gel, and proteins subsequently identified by analytical mass spectrometry. Peptide fractionation according to their pI is also widely used in current proteomics sample preparation procedures previous to the LC-MS/MS analysis. Therefore accurate theoretical prediction of pI would expedite such analysis. While such pI calculation is widely used, it remains largely untested, motivating our efforts to benchmark pI prediction methods. Results: Using data from the database PIP-DB and one publically available dataset as our reference gold standard, we have undertaken the benchmarking of pI calculation methods. We find that methods vary in their accuracy and are highly sensitive to the choice of basis set. The machine-learning algorithms, especially the SVM-based algorithm, showed a superior performance when studying peptide mixtures. In general, learning-based pI prediction methods (such as Cofactor, SVM and Branca) require a large training dataset and their resulting performance will strongly depend of the quality of that data. In contrast with Iterative methods, machine-learning algorithms have the advantage of being able to add new features to improve the accuracy of prediction. Contact: yperez@ebi.ac.uk Availability and Implementation: The software and data are freely available at https://github.com/ypriverol/pIR. Supplementary information:Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Enrique Audain
- Department of Proteomics, Center of Molecular Immunology
| | - Yassel Ramos
- Department of Proteomics, Center for Genetic Engineering and Biotechnology, Ciudad de la Habana, Cuba
| | - Henning Hermjakob
- Department European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK and
| | - Darren R Flower
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK
| | - Yasset Perez-Riverol
- Department European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK and
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8
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ProCon — PROteomics CONversion tool. J Proteomics 2015; 129:56-62. [DOI: 10.1016/j.jprot.2015.06.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/19/2015] [Accepted: 06/28/2015] [Indexed: 11/22/2022]
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9
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Kizzie-Hayford N, Jaros D, Schneider Y, Rohm H. Physico-chemical properties of globular tiger nut proteins. Eur Food Res Technol 2015. [DOI: 10.1007/s00217-015-2508-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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10
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FUKUDA J, IWURA T, YANAGIHARA S, KANO K. Factors to Govern Soluble and Insoluble Aggregate-formation in Monoclonal Antibodies. ANAL SCI 2015; 31:1233-40. [DOI: 10.2116/analsci.31.1233] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jun FUKUDA
- Graduate School of Agriculture, Kyoto University
- Bio Process Research and Development Laboratories, Production Division, Kyowa Hakko Kirin Co., Ltd
| | - Takafumi IWURA
- Bio Process Research and Development Laboratories, Production Division, Kyowa Hakko Kirin Co., Ltd
| | - Shigehiro YANAGIHARA
- Bio Process Research and Development Laboratories, Production Division, Kyowa Hakko Kirin Co., Ltd
| | - Kenji KANO
- Graduate School of Agriculture, Kyoto University
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11
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Ali L, Flowers SA, Jin C, Bennet EP, Ekwall AKH, Karlsson NG. The O-glycomap of lubricin, a novel mucin responsible for joint lubrication, identified by site-specific glycopeptide analysis. Mol Cell Proteomics 2014; 13:3396-409. [PMID: 25187573 PMCID: PMC4256492 DOI: 10.1074/mcp.m114.040865] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 08/15/2014] [Indexed: 11/06/2022] Open
Abstract
The lubricative, heavily glycosylated mucin-like synovial glycoprotein lubricin has previously been observed to contain glycosylation changes related to rheumatoid and osteoarthritis. Thus, a site-specific investigation of the glycosylation of lubricin was undertaken, in order to further understand the pathological mechanisms involved in these diseases. Lubricin contains an serine/threonine/proline (STP)-rich domain composed of imperfect tandem repeats (EPAPTTPK), the target for O-glycosylation. In this study, using a liquid chromatography-tandem mass spectrometry approach, employing both collision-induced and electron-transfer dissociation fragmentation methods, we identified 185 O-glycopeptides within the STP-rich domain of human synovial lubricin. This showed that adjacent threonine residues within the central STP-rich region could be simultaneously and/or individually glycosylated. In addition to core 1 structures responsible for biolubrication, core 2 O-glycopeptides were also identified, indicating that lubricin glycosylation may have other roles. Investigation of the expression of polypeptide N-acetylgalactosaminyltransferase genes was carried out using cultured primary fibroblast-like synoviocytes, a cell type that expresses lubricin in vivo. This analysis showed high mRNA expression levels of the less understood polypeptide N-acetylgalactosaminyltransferase 15 and 5 in addition to the ubiquitously expressed polypeptide N-acetylgalactosaminyltransferase 1 and 2 genes. This suggests that there is a unique combination of transferase genes important for the O-glycosylation of lubricin. The site-specific glycopeptide analysis covered 82% of the protein sequence and showed that lubricin glycosylation displays both micro- and macroheterogeneity. The density of glycosylation was shown to be high: 168 sites of O-glycosylation, predominately sialylated, were identified. These glycosylation sites were focused in the central STP-rich region, giving the domain a negative charge. The more positively charged lysine and arginine residues in the N and C termini suggest that synovial lubricin exists as an amphoteric molecule. The identification of these unique properties of lubricin may provide insight into the important low-friction lubricating functions of lubricin during natural joint movement.
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Affiliation(s)
- Liaqat Ali
- From the ‡Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Box 440, Medicinaregatan 9A, 405 30, Gothenburg, Sweden
| | - Sarah A Flowers
- From the ‡Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Box 440, Medicinaregatan 9A, 405 30, Gothenburg, Sweden
| | - Chunsheng Jin
- From the ‡Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Box 440, Medicinaregatan 9A, 405 30, Gothenburg, Sweden
| | - Eric Paul Bennet
- §Department of Odontology, Copenhagen Center for Glycomics, University of Copenhagen, Norre Alle 20, DK-2200 Copenhagen N, Denmark
| | - Anna-Karin H Ekwall
- ¶Department of Rheumatology and Inflammation Research, Institute of Medicine, University of Gothenburg, Guldhedsgatan 10A, SE-41346, Gothenburg, Sweden
| | - Niclas G Karlsson
- From the ‡Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Box 440, Medicinaregatan 9A, 405 30, Gothenburg, Sweden;
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12
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Bunkute E, Cummins C, Crofts FJ, Bunce G, Nabney IT, Flower DR. PIP-DB: the Protein Isoelectric Point database. Bioinformatics 2014; 31:295-6. [PMID: 25252779 DOI: 10.1093/bioinformatics/btu637] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED A protein's isoelectric point or pI corresponds to the solution pH at which its net surface charge is zero. Since the early days of solution biochemistry, the pI has been recorded and reported, and thus literature reports of pI abound. The Protein Isoelectric Point database (PIP-DB) has collected and collated these data to provide an increasingly comprehensive database for comparison and benchmarking purposes. A web application has been developed to warehouse this database and provide public access to this unique resource. PIP-DB is a web-enabled SQL database with an HTML GUI front-end. PIP-DB is fully searchable across a range of properties. AVAILABILITY AND IMPLEMENTATION The PIP-DB database and documentation are available at http://www.pip-db.org.
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Affiliation(s)
- Egle Bunkute
- School of Life and Health Sciences and School of Engineering and Applied Science, University of Aston, Aston Triangle, Birmingham B4 7ET, UK
| | - Christopher Cummins
- School of Life and Health Sciences and School of Engineering and Applied Science, University of Aston, Aston Triangle, Birmingham B4 7ET, UK
| | - Fraser J Crofts
- School of Life and Health Sciences and School of Engineering and Applied Science, University of Aston, Aston Triangle, Birmingham B4 7ET, UK
| | - Gareth Bunce
- School of Life and Health Sciences and School of Engineering and Applied Science, University of Aston, Aston Triangle, Birmingham B4 7ET, UK
| | - Ian T Nabney
- School of Life and Health Sciences and School of Engineering and Applied Science, University of Aston, Aston Triangle, Birmingham B4 7ET, UK
| | - Darren R Flower
- School of Life and Health Sciences and School of Engineering and Applied Science, University of Aston, Aston Triangle, Birmingham B4 7ET, UK
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13
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Separation and quantification of monoclonal-antibody aggregates by hollow-fiber-flow field-flow fractionation. Anal Bioanal Chem 2014; 406:6257-64. [DOI: 10.1007/s00216-014-8065-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 07/16/2014] [Accepted: 07/24/2014] [Indexed: 10/24/2022]
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14
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Withana-Gamage TS, Hegedus DD, Qiu X, McIntosh T, Wanasundara JPD. Structural and physicochemical property relationships of cruciferin homohexamers. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:5848-5859. [PMID: 23738812 DOI: 10.1021/jf400559x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Heteromeric cruciferin from wild type (WT) Arabidopsis thaliana and homomeric cruciferin CRUA, CRUB, and CRUC composed of identical subunits obtained from double-knockout mutant lines were investigated for their structural and physicochemical properties. A three-step chromatographic procedure allowed isolation of intact cruciferin hexamers with high purity (>95%). FT-IR and CD analysis of protein secondary structure composition revealed that all cruciferins were folded into higher order structures consisting of 44-50% β-sheets and 7-9% α-helices. The structural and physicochemical properties of homohexameric CRUC deviated from that of CRUA and CRUB and exhibited a compact, thermostable, and less hydrophobic structure, confirming the predictions made using 3D homology structure models.
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15
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Behrens C, Hartmann K, Sunderhaus S, Braun HP, Eubel H. Approximate calculation and experimental derivation of native isoelectric points of membrane protein complexes of Arabidopsis chloroplasts and mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013. [DOI: 10.1016/j.bbamem.2012.11.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Ruinatscha R, Karande R, Buehler K, Schmid A. Integrated one-pot enrichment and immobilization of styrene monooxygenase (StyA) using SEPABEAD EC-EA and EC-Q1A anion-exchange carriers. Molecules 2011; 16:5975-88. [PMID: 21769063 PMCID: PMC6264573 DOI: 10.3390/molecules16075975] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 07/12/2011] [Indexed: 11/25/2022] Open
Abstract
A straightforward one-pot procedure combining enrichment and immobilization of recombinantely expressed FADH2 dependent styrene monooxygenase (StyA) directly from Escherichia coli cell extracts was investigated. Sepabeads EC-EA and EC-Q1A anion-exchange carriers were employed to non-covalently adsorb StyA from the cell extracts depending on basic parameters such as varying initial protein concentrations and pH. The protein fraction of the cell extract contained around 25% StyA. At low initial protein concentrations (2.5 mg mL−1) and pH 6, the enzyme could be enriched up to 52.4% on Sepabeads EC-EA and up to 46.0% on Sepabeads EC-Q1A, accounting for an almost complete StyA adsorption from the cell extracts. Higher initial protein concentrations were necessary to exploit the high loading capacity of the beads. At 20 mg mL−1, up to 37.6% of the theoretical bead loading capacity could be utilized for StyA binding using Sepabeads EC-EA, and 34.0% using Sepabeads EC-Q1A. For both carriers, protein leakage under reaction conditions could be reduced to less than 2%. During assays, the FADH2 cofactor necessary for StyA activity was supplied by the NADH-FAD reductase component styrene monooxygenase B (StyB). StyA immobilized on Sepabeads EC-Q1A displayed twice as high styrene epoxidation rates (0.2 U mgStyA−1) as compared to Sepabeads EC-EA. This activity could be increased to 0.7 U mgStyA−1 by co-immobilizing StyB on Sepabeads EC-Q1A, which corresponds to 33% of the soluble StyA activity.
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Affiliation(s)
| | | | | | - Andreas Schmid
- Author to whom correspondence should be addressed; ; Tel.: +49-231-755-7380; Fax: +49-231-755-7382
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Gupta R, Baldock SJ, Fielden PR, Grieve BD. Capillary zone electrophoresis for the analysis of glycoforms of cellobiohydrolase. J Chromatogr A 2011; 1218:5362-8. [PMID: 21726866 DOI: 10.1016/j.chroma.2011.06.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 06/08/2011] [Accepted: 06/09/2011] [Indexed: 02/01/2023]
Abstract
Cellobiohydrolase (CBH) is an important enzyme for the conversion of lignocellulosic biomass to ethanol. This work separated the glycoforms of CBH possessing different numbers of neutral mannoses using capillary zone electrophoresis (CZE) in a 50 mM, pH 7.5 phosphate buffer. The method analysed CBH in an intact form using a polyacrylamide coated fused silica capillary without requiring additives or labelling of the enzyme. The migration time of the major peak was found to be 21.6±0.1 min (n=3) and the approach is suitable for testing of batch-to-batch consistency of CBH. Ease-of-use, automation and speed are the other benefits due to which the use of CZE for analysing glycoforms of CBH was concluded to be ideal.
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Affiliation(s)
- Ruchi Gupta
- School of Electrical and Electronics Engineering, The University of Manchester, Sackville Street Building, Sackville Street, Manchester M13 9PL, UK.
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18
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Gupta R, Baldock SJ, Fielden PR, Grieve BD. A specific, robust, and automated method for routine at-line monitoring of the concentration of cellulases in genetically modified sugarcane plants. Appl Biochem Biotechnol 2010; 163:528-39. [PMID: 21136205 DOI: 10.1007/s12010-010-9059-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Accepted: 08/09/2010] [Indexed: 11/28/2022]
Abstract
Bagasse is one of the waste crop materials highlighted as commercially viable for cellulosic bio-ethanol production via enzymatic conversion to release fermentable sugars. Genetically modified sugarcane expressing cellobiohydrolases (CBH), endoglucanase (EG), and β-glucosidases (BG) provide a more cost-effective route to cellulose breakdown compared to culturing these enzymes in microbial tanks. Hence, process monitoring of the concentration profile of these key cellulases in incoming batches of sugarcane is required for fiscal measures and bio-ethanol process control. The existing methods due to their non-specificity, requirement of trained analysts, low sample throughput, and low amenability to automation are unsuitable for this purpose. Therefore, this paper explores a membrane-based sample preparation method coupled to capillary zone electrophoresis (CZE) to quantify these enzymes. The maximum enzyme extraction efficiency was obtained by using a polyethersulfone membrane with molecular cut-off of 10 kDa. The use of 15 mM, pH 7.75, phosphate buffer resulted in CZE separation and quantification of CBH, EG, and BG within 10 min. Migration time reproducibility was between 0.56% and 0.7% and hence, suitable for use with automatic peak detection software. Therefore, the developed CZE method is suitable for at-line analysis of BG, CBH, and EG in every batch of harvested sugarcane.
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Affiliation(s)
- Ruchi Gupta
- School of Electrical and Electronics Engineering, The University of Manchester, Sackville Street Building, Manchester M139PL, UK.
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19
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Maldonado A, Vara F, Sillero A. Improved application of the oscillating method for the isoelectric point determination of protein: Potential connection with protein data banks. Comput Biol Med 2008; 38:23-30. [PMID: 17655838 DOI: 10.1016/j.compbiomed.2007.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Revised: 05/23/2007] [Accepted: 06/11/2007] [Indexed: 10/23/2022]
Abstract
The oscillating method (OM) for the theoretical determination of the pI values, one by one, of proteins and other macromolecules has been previously published [Sillero and Maldonado, Comput. Biol. Med 36 (2006) 157-166]. An improved application of the method, here named as improved oscillating method (IOM), allows the pI determination of group of proteins. This characteristic may be useful to explore the pI value and electric charge of family of enzymes. As an example the pI values of 1630 enzymes collected in a Swiss-Prot data bank (www.expasy.org), as belonging to the enzymes ligases (EC 6. 2. 1. *) is presented. The method also permits the determination of the pI value of any group of proteins stored in data banks provided that they can be supplied to the program in a FASTA format. Free access to IOM can be reached at http://www.bq.uam.es/otros/pical3.zip.
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Affiliation(s)
- Andrés Maldonado
- Departmento de Bioquímica, Facultad de Medicina, Instituto de Investigaciones Biomédicas Alberto Sols (UAM/CSIC), Arzobispo Morcillo 4, 28029 Madrid, Spain
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20
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Strong RA, Liu H, Krull IS, Cho BY, Cohen SA. ADVANTAGES AND LIMITATIONS OF DERIVATIZATION OF PEPTIDES FOR IMPROVED PERFORMANCE AND DETECTABILITY IN CAPILLARY ISOELECTRIC FOCUSING (CIEF). J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-100100451] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Richard A. Strong
- a Department of Chemistry , Northeastern University , 102 Hurtig Building 360 Huntington Avenue, Boston, MA, 02115, U.S.A
| | - Hongji Liu
- a Department of Chemistry , Northeastern University , 102 Hurtig Building 360 Huntington Avenue, Boston, MA, 02115, U.S.A
| | - Ira S. Krull
- b Department of Chemistry , Northeastern University , 102 Hurtig Building 360 Huntington Avenue, Boston, MA, 02115, U.S.A
| | | | - Steven A. Cohen
- c Biotechnology Applications Laboratory , Waters Corporation , 34 Maple Street, Milford, MA, 01757, U.S.A
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Sillero A, Maldonado A. Isoelectric point determination of proteins and other macromolecules: oscillating method. Comput Biol Med 2005; 36:157-66. [PMID: 16389075 DOI: 10.1016/j.compbiomed.2004.09.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Accepted: 09/07/2004] [Indexed: 10/26/2022]
Abstract
A program written in Visual Basic has been developed to calculate the isoelectric point of proteins and other macromolecules bearing acid-basic residues. The pI value can be theoretically calculated with the precision required. The computer automatically supplies a representation of the charge of the protein versus pH values. The corresponding values can also be obtained, on command, in the form of table.
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Affiliation(s)
- Antonio Sillero
- Facultad de Medicina, Departamento de Bioquímica, Instituto de Investigaciones Biomédicas Alberto Sols, CSIC/UAM, Madrid, Spain.
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Bignell DRD, Lau LH, Colvin KR, Leskiw BK. The putative anti-anti-sigma factor BldG is post-translationally modified by phosphorylation in Streptomyces coelicolor. FEMS Microbiol Lett 2003; 225:93-9. [PMID: 12900026 DOI: 10.1016/s0378-1097(03)00504-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The Streptomyces coelicolor bldG gene encodes a protein showing similarity to the SpoIIAA and RsbV anti-anti-sigma factors of Bacillus subtilis. Purified maltose binding protein-BldG could be phosphorylated in vitro by wild-type S. coelicolor crude extract, and both the phosphorylated and unphosphorylated forms of BldG could be detected in vivo using isoelectric focusing. ATP was shown to serve as the phosphoryl group donor, and phosphorylation of BldG was abolished when the putative phosphorylation site was changed from a serine to an alanine residue. A bldG mutant strain expressing the non-phosphorylatable BldG protein was unable to undergo morphological differentiation or produce antibiotics even after prolonged incubation, suggesting that phosphorylation of BldG is necessary for proper development in S. coelicolor.
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Affiliation(s)
- Dawn R D Bignell
- Department of Biological Sciences, CW405 Biological Sciences Building, University of Alberta, Edmonton, AB, Canada T6G 2E9
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Yousaf N, Deng Y, Kang Y, Riedel H. Four PSM/SH2-B alternative splice variants and their differential roles in mitogenesis. J Biol Chem 2001; 276:40940-8. [PMID: 11502739 DOI: 10.1074/jbc.m104191200] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
An SH2 domain originally termed SH2-B had been identified as a direct cellular binding target of a number of mostly mitogenic receptors. The complete cellular protein, termed PSM, and respective sequence variants share additional Pro-rich and PH regions, as well as similarities with APS and Lnk. A role of these mediators has been implicated in signaling pathways found downstream of growth hormone receptor and receptor tyrosine kinases, including the insulin, insulin-like growth factor-I (IGF-I), platelet-derived growth factor (PDGF), nerve growth factor, hepatocyte growth factor, and fibroblast growth factor receptors. As a result of this report a total of four PSM/SH2-B sequence variants termed alpha, beta, gamma, and delta have now been identified in the mouse and have been compared with the available rat and human sequences. Variant differences are based on alternative splicing and define distinct last exons 7, 8, and 9 that result in reading frameshifts and unique carboxyl-terminal amino acid sequences. Variant sequences have been identified from cDNA libraries and directly by reverse transcription-polymerase chain reaction. Sequence analysis predicts four distinctly sized protein products that have been demonstrated after cDNA expression. All were found phosphorylated on tyrosine specifically in response to IGF-I and PDGF stimulation. cDNA expression of the four variants caused variant-dependent levels of stimulation of IGF-I- and PDGF-induced mitogenesis. The most pronounced increase in mitogenesis was consistently observed for the gamma variant followed by delta, alpha, and beta with decreasing responses. In contrast, the mitogenic response to epidermal growth factor consistently remained unaffected. The variants are expressed in most mouse tissues, typically, most strongly in pairs of alpha and delta or beta and gamma. Our findings implicate differential roles of the PSM/SH2-B splice variants in specific mitogenic signaling pathways.
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Affiliation(s)
- N Yousaf
- Department of Biological Sciences, Wayne State University, Detroit, Michigan 48202, USA
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Lagerquist C, Beigi F, Karlén A, Lennernäs H, Lundahl P. Effects of cholesterol and model transmembrane proteins on drug partitioning into lipid bilayers as analysed by immobilized-liposome chromatography. J Pharm Pharmacol 2001; 53:1477-87. [PMID: 11732750 DOI: 10.1211/0022357011778016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
We have analysed how cholesterol and transmembrane proteins in phospholipid bilayers modulate drug partitioning into the bilayers. For this purpose we determined the chromatographic retention of drugs on liposomes or proteoliposomes entrapped in gel beads. The drug retention per phospholipid amount (the capacity factor Ks) reflects the drug partitioning. Cholesterol in the bilayers decreased the Ks value and hence the partitioning into the membrane in proportion to the cholesterol fraction. On average this cholesterol effect decreased with increasing temperature. Model transmembrane proteins, the glucose transporter GLUT1 and bacteriorhodopsin, interacted electrostatically with charged drugs to increase or decrease the drug partitioning into the bilayers. Bacteriorhodopsin proteoliposomes containing cholesterol combined the effects of the protein and the cholesterol and approached the partitioning properties of red blood cell membranes. For positively charged drugs the correlation between calculated intestinal permeability and log Ks was fair for both liposomes and bacteriorhodopsin-cholesterol proteoliposomes. Detailed modeling of solute partitioning into biological membranes may require an extensive knowledge of their structures.
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Affiliation(s)
- C Lagerquist
- Department of Biochemistry, Uppsala Biomedical Center, Uppsala University, Sweden
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25
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Lindy O, Konttinen YT, Sorsa T, Ding Y, Santavirta S, Ceponis A, López-Otín C. Matrix metalloproteinase 13 (collagenase 3) in human rheumatoid synovium. ARTHRITIS AND RHEUMATISM 1997; 40:1391-9. [PMID: 9259418 DOI: 10.1002/art.1780400806] [Citation(s) in RCA: 167] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To show the eventual presence and extent of production of matrix metalloproteinase 13 (MMP-13, or collagenase 3) in rheumatoid synovial tissue samples and extracts, and to assess the inhibition characteristics of recombinant MMP-13. METHODS Immunohistochemical avidin-biotin-peroxidase complex staining/morphometry was used to analyze MMP-13-positive cells in situ. Neutral salt extraction of synovial tissue, electrophoresis of the extract in different buffer systems, and Western blotting were also used. The inhibitory properties of doxycycline, clodronate, pamidronate, and D-penicillamine for recombinant enzyme were determined with a soluble type II collagen assay. RESULTS MMP-13 was detected in fibroblast- and macrophage-like mononuclear cells in the synovial lining and stroma and in vascular endothelial cells. The overall expression of MMP-13 in these cells in the synovial stroma was high in rheumatoid arthritis (86 +/- 12%) compared with osteoarthritis (17 +/- 5%) patient samples (P = 0.0027). In a high-pH native electrophoresis gel, immunoreactivity to anti-MMP-1 and anti-MMP-13 were clearly separated, with anti-MMP-13-immunoreactive material migrating faster than anti-MMP-1-immunoreactive material. Finally, in contrast to MMP-1 and MMP-8, MMP-13 was found to be relatively resistant to the inhibitory effects of doxycycline and clodronate in vitro. CONCLUSION Due to its localization in synovial tissue, its substrate profile, increased expression, and relative resistance to known MMP inhibitors, MMP-13 is suggested to play a major role in the pathogenesis of tissue destruction in rheumatoid arthritis.
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Affiliation(s)
- O Lindy
- University of Helsinki, Finland
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Lu L, Lundqvist A, Zeng CM, Lagerquist C, Lundahl P. D-Glucose, forskolin and cytochalasin B affinities for the glucose transporter Glut1. Study of pH and reconstitution effects by biomembrane affinity chromatography. J Chromatogr A 1997; 776:81-6. [PMID: 9286080 DOI: 10.1016/s0021-9673(97)00151-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The affinities of D-glucose and the transport inhibitors, forskolin and cytochalasin B (CB), for Glut1 were studied by frontal affinity chromatography at pH 5-10 on sterically immobilized proteoliposomes with reconstituted human red cell glucose transporter Glut1. The affinity of D-glucose for Glut1 became slightly weaker as the pH was increased. The inhibitor affinities decreased and became immeasurably weak above pH 9. At pH 7.4, the dissociation constants were 44 mM for glucose, 1.8 microM for forskolin and 72 nM for CB. The affinities of these solutes for Glut1 in red cell membrane vesicles and particularly for Glut1 in red cells were higher, as shown by chromatographic analyses.
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Affiliation(s)
- L Lu
- Department of Biochemistry, Uppsala University, Sweden
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