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Lu G, Ying G, He Y, Li Y, Zhang Z. Integrated MICROFASP Method with CZE-Based Fractionation Technique and NanoRPLC-ESI-MS/MS for a Comprehensive Proteomics Analysis of a Submicrogram Sample. J Proteome Res 2024; 23:3696-3703. [PMID: 39013029 DOI: 10.1021/acs.jproteome.4c00396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
We report a loss-less two-dimensional (2D) separation platform that integrated capillary zone electrophoresis (CZE) fractionation and nanoRPLC-ESI-MS/MS for a comprehensive proteomics analysis of a submicrogram sample. Protein digest was injected into the linear polyacrylamide-coated capillary, followed by CZE separation. The schemes for collecting the fractions were carefully optimized to maximize the protein coverage. The peptide fractions were directly eluted into the autosampler insert vials, followed by the nanoRPLC-ESI-MS/MS analysis without lyophilization and redissolution, thus dramatically minimizing sample loss and potential contamination. The integrated platform generated 30,845 unique peptides and 5231 protein groups from 500 ng of a HeLa protein digest within 11.5 h (90 min CZE fractionation plus 10 h LC-MS analysis). Finally, the developed platform was used to analyze the protein digest prepared by the MICROFASP method with 1 μg of cell lysate as the starting material. Three thousand seven hundred ninety-six (N = 2, RSD = 4.95%) protein groups and 20,577 (N = 2, RSD = 7.89%) peptides were identified from only 200 ng of the resulted tryptic digest within 5.5 h. The results indicated that the combination of the MICROFASP method and the developed CZE/nanoRPLC-MS/MS 2D separation platform enabled comprehensive proteome profiling of a submicrogram biological sample. Data are available via ProteomeXchange with the identifier PXD052735.
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Affiliation(s)
- Gang Lu
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Guojin Ying
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Yu He
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Yang Li
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Zhenbin Zhang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
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2
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Colón Rosado J, Sun L. Solid-Phase Microextraction-Aided Capillary Zone Electrophoresis-Mass Spectrometry: Toward Bottom-Up Proteomics of Single Human Cells. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1120-1127. [PMID: 38514245 PMCID: PMC11157658 DOI: 10.1021/jasms.3c00429] [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: 12/13/2023] [Revised: 03/02/2024] [Accepted: 03/13/2024] [Indexed: 03/23/2024]
Abstract
Capillary zone electrophoresis-mass spectrometry (CZE-MS) has been recognized as a valuable technique for the proteomics of mass-limited biological samples (i.e., single cells). However, its broad adoption for single cell proteomics (SCP) of human cells has been impeded by the low sample loading capacity of CZE, only allowing us to use less than 5% of the available peptide material for each measurement. Here we present a reversed-phase-based solid-phase microextraction (RP-SPME)-CZE-MS platform to solve the issue, paving the way for SCP of human cells using CZE-MS. The RP-SPME-CZE system was constructed in one fused silica capillary with zero dead volume for connection via in situ synthesis of a frit, followed by packing C8 beads into the capillary to form a roughly 2 mm long SPME section. Peptides captured by SPME were eluted with a buffer containing 30% (v/v) acetonitrile and 50 mM ammonium acetate (pH 6.5), followed by dynamic pH junction-based CZE-MS. The SPME-CZE-MS enabled the injection of nearly 40% of the available peptide sample for each measurement. The system identified 257 ± 24 proteins and 523 ± 69 peptides (N = 2) using a Q-Exactive HF mass spectrometer when only 0.25 ng of a commercial HeLa cell digest was available in the sample vial and 0.1 ng of the sample was injected. The amount of available peptide is equivalent to the protein mass of one HeLa cell. The data indicate that SPME-CZE-MS is ready for SCP of human cells.
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Affiliation(s)
- Jorge
A. Colón Rosado
- Department of Chemistry, Michigan
State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
| | - Liangliang Sun
- Department of Chemistry, Michigan
State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
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3
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Nagy C, Andrasi M, Szabo R, Gaspar A. CZE-MS peptide mapping: To desalt or not to desalt? Anal Chim Acta 2024; 1288:342162. [PMID: 38220294 DOI: 10.1016/j.aca.2023.342162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 12/10/2023] [Accepted: 12/16/2023] [Indexed: 01/16/2024]
Abstract
BACKGROUND In "shotgun" approaches involving high-performance liquid chromatography or capillary zone electrophoresis (CZE), matrix removal prior to sample analysis is considered as an indispensable tool. Despite the fact that CZE offers a high tolerance towards salts, most publications reported on the use of desalting. There seems to be no clear consensus on the utilization of desalting in the CZE-MS community, most probably due to the absence of works addressing the comparison of desalted and non-desalted digests. Our aim was to fill this research gap using protein samples of varying complexity in different sample matrices. RESULTS First, standard protein digests were analyzed to build the knowledge on the effect of sample clean-up by solid-phase extraction (SPE) pipette tips and the possible stacking phenomena induced by different sample matrices. Desalting led to a somewhat altered peptide profile, the procedure affected mostly the hydrophilic peptides (although not to a devastating extent). Nevertheless, desalting samples allowed remarkable stacking efficiency owing to their low-conductivity sample background, enabling a so-called field-amplified sample stacking phenomenon. Non-desalted samples also produced a stacking event, the mechanism of which is based on transient-isotachophoresis due to the presence of high-mobility ions in the digestion buffer itself. Adding either extra ammonium ions or acetonitrile into the non-desalted digests enhanced the stacking efficiency. A complex sample (yeast cell lysate) was also analyzed with the optimal conditions, which yielded similar tendencies. SIGNIFICANCE Based on these results, we propose that sample clean-up in the bottom-up sample preparation process prior to CZE-MS analysis can be omitted. The preclusion of desalting can even enhance detection sensitivity, separation efficiency or sequence coverage.
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Affiliation(s)
- Cynthia Nagy
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary
| | - Melinda Andrasi
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary
| | - Ruben Szabo
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary
| | - Attila Gaspar
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary.
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4
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Bagwe K, Gould N, Johnson KR, Ivanov AR. Single-cell omic molecular profiling using capillary electrophoresis-mass spectrometry. Trends Analyt Chem 2023; 165:117117. [PMID: 37388554 PMCID: PMC10306258 DOI: 10.1016/j.trac.2023.117117] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
Tissues and other cell populations are highly heterogeneous at the cellular level, owing to differences in expression and modifications of proteins, polynucleotides, metabolites, and lipids. The ability to assess this heterogeneity is crucial in understanding numerous biological phenomena, including various pathologies. Traditional analyses apply bulk-cell sampling, which masks the potentially subtle differences between cells that can be important in understanding of biological processes. These limitations due to cell heterogeneity inspired significant efforts and interest toward the analysis of smaller sample sizes, down to the level of individual cells. Among the emerging techniques, the unique capabilities of capillary electrophoresis coupled with mass spectrometry (CE-MS) made it a prominent technique for proteomics and metabolomics analysis at the single-cell level. In this review, we focus on the application of CE-MS in the proteomic and metabolomic profiling of single cells and highlight the recent advances in sample preparation, separation, MS acquisition, and data analysis.
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Affiliation(s)
- Ketki Bagwe
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
| | - Noah Gould
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
| | - Kendall R. Johnson
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
| | - Alexander R. Ivanov
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
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5
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Aerts J, Andrén PE, Jansson ET. Zero-Degree Celsius Capillary Electrophoresis Electrospray Ionization for Hydrogen Exchange Mass Spectrometry. Anal Chem 2022; 95:1149-1158. [PMID: 36546842 PMCID: PMC9850406 DOI: 10.1021/acs.analchem.2c03893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Currently, fast liquid chromatographic separations at low temperatures are exclusively used for the separation of peptides generated in hydrogen deuterium exchange (HDX) workflows. However, it has been suggested that capillary electrophoresis may be a better option for use with HDX. We performed in solution HDX on peptides and bovine hemoglobin (Hb) followed by quenching, pepsin digestion, and cold capillary electrophoretic separation coupled with mass spectrometry (MS) detection for benchmarking a laboratory-built HDX-MS platform. We found that capillaries with a neutral coating to eliminate electroosmotic flow and adsorptive processes provided fast separations with upper limit peak capacities surpassing 170. In contrast, uncoated capillaries achieved 30% higher deuterium retention for an angiotensin II peptide standard owing to faster separations but with only half the peak capacity of coated capillaries. Data obtained using two different separation conditions on peptic digests of Hb showed strong agreement of the relative deuterium uptake between methods. Processed data for denatured versus native Hb after deuterium labeling for the longest timepoint in this study (50,000 s) also showed agreement with subunit interaction sites determined by crystallographic methods. All proteomic data are available under DOI: 10.6019/PXD034245.
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Affiliation(s)
- Jordan
T. Aerts
- Department
of Pharmaceutical Biosciences, Uppsala University, Uppsala751 24, Sweden
| | - Per E. Andrén
- Department
of Pharmaceutical Biosciences, Uppsala University, Uppsala751 24, Sweden,Science
for Life Laboratory, Spatial Mass Spectrometry, Uppsala University, Uppsala751 24, Sweden
| | - Erik T. Jansson
- Department
of Pharmaceutical Biosciences, Uppsala University, Uppsala751 24, Sweden,
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6
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Kašička V. Peptide mapping of proteins by capillary electromigration methods. J Sep Sci 2022; 45:4245-4279. [PMID: 36200755 DOI: 10.1002/jssc.202200664] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/26/2022] [Accepted: 09/26/2022] [Indexed: 12/13/2022]
Abstract
This review article provides a wide overview of important developments and applications of capillary electromigration methods in the area of peptide mapping of proteins in the period 1997-mid-2022, including review articles on this topic. It deals with all major aspects of peptide mapping by capillary electromigration methods: i) precleavage sample preparation involving purification, preconcentration, denaturation, reduction and alkylation of protein(s) to be analyzed, ii) generation of peptide fragments by off-line or on-line enzymatic and/or chemical cleavage of protein(s), iii) postcleavage preparation of the generated peptide mixture for capillary electromigration separation, iv) separation of the complex peptide mixtures by one-, two- and multidimensional capillary electromigration methods coupled with mass spectrometry detection, and v) a large application of peptide mapping for variable purposes, such as qualitative analysis of monoclonal antibodies and other protein biopharmaceuticals, monitoring of posttranslational modifications, determination of primary structure and investigation of function of proteins in biochemical and clinical research, characterization of proteins of variable origin as well as for protein and peptide identification in proteomic and peptidomic studies.
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Affiliation(s)
- Václav Kašička
- Electromigration Methods, The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czechia
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7
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Sun BK, Wang RY, Li B, Fan X, Zhou Y, Gu B, Yan YY. Rapid identification of polypeptide from carbapenem-resistant and susceptible Escherichia coli via Orbitrap-MS and pattern recognition analyses. Chem Biodivers 2022; 19:e202200118. [PMID: 35925667 DOI: 10.1002/cbdv.202200118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 08/03/2022] [Indexed: 11/10/2022]
Abstract
A rapid and accurate analytical method was established to identify CREC and CSEC. Orbitrap-MS was used to detect the polypeptide of CREC and CSEC strains, and MS data were analyzed by pattern recognition analyses such as hierarchical cluster analysis (HCA), principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA). HCA based on the farthest distance method could well distinguish the two types of E. coli, and the cophenetic correlation coefficient of the farthest distance method was 0.901. Comparing the results of PCA, PLS-DA, and OPLS-DA, OPLS-DA exhibited the highest accuracy in predicting the CREC and CSEC strains. A total of 26 compounds were identified, and six of the compounds were the highly significant difference between the two types of strains. MS combined with pattern recognition can achieve a more comprehensive and efficient statistical analysis of complex biological samples.
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Affiliation(s)
- Bing-Kang Sun
- China University of Mining and Technology, Low Carbon Energy Institute, No. 1, University Road, Xuzhou, CHINA
| | - Rui-Yu Wang
- China University of Mining and Technology, Low Carbon Energy Institute, No. 1, University Road, Xuzhou, CHINA
| | - Bei Li
- China University of Mining and Technology, Low Carbon Energy Institute, No. 1, University Road, Xuzhou, CHINA
| | - Xing Fan
- Shandong University of Science and Technology, 579 Qianwangang Road, 266590, Qingdao, CHINA
| | - Yuan Zhou
- Xuzhou Medical University, College of Medical Technology, 209 Tongshan Road, Xuzhou, CHINA
| | - Bing Gu
- Xuzhou Medical University, College of Medical Technology, No. 209 Tongshan Road, Xuzhou, CHINA
| | - Yang-Yang Yan
- China University of Mining and Technology, Low Carbon Energy Institute, No. 1, University Road, Xuzhou, CHINA
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8
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Abstract
Biological mass spectrometry (MS) encompasses a range of methods for characterizing proteins and other biomolecules. MS is uniquely powerful for the structural analysis of endogenous protein complexes, which are often heterogeneous, poorly abundant, and refractive to characterization by other methods. Here, we focus on how biological MS can contribute to the study of endogenous protein complexes, which we define as complexes expressed in the physiological host and purified intact, as opposed to reconstituted complexes assembled from heterologously expressed components. Biological MS can yield information on complex stoichiometry, heterogeneity, topology, stability, activity, modes of regulation, and even structural dynamics. We begin with a review of methods for isolating endogenous complexes. We then describe the various biological MS approaches, focusing on the type of information that each method yields. We end with future directions and challenges for these MS-based methods.
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Affiliation(s)
- Rivkah Rogawski
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Michal Sharon
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
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9
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Yang Z, Zhang Z, Chen D, Xu T, Wang Y, Sun L. Nanoparticle-Aided Nanoreactor for Nanoproteomics. Anal Chem 2021; 93:10568-10576. [PMID: 34297524 DOI: 10.1021/acs.analchem.1c01704] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Large-scale bottom-up proteomics of few even single cells is crucial for a better understanding of the roles played by cell-to-cell heterogeneity in disease and development. Novel proteomic methodologies with extremely high sensitivity are required for few even single-cell proteomics. Sample processing with high recovery and no contaminants is one key step. Here we developed a nanoparticle-aided nanoreactor for nanoproteomics (Nano3) technique for processing low-nanograms of mammalian cell proteins for proteome profiling. The Nano3 technique employed nanoparticles packed in a capillary channel to form a nanoreactor (≤30 nL) for concentrating, cleaning, and digesting proteins originally in a lysis buffer containing sodium dodecyl sulfate (SDS), followed by nanoRPLC-MS/MS analysis. The Nano3 method identified a 40-times higher number of proteins based on MS/MS from 2-ng mouse brain protein samples compared to the SP3 (single-pot solid-phase-enhanced sample preparation) method, which performed the sample processing using the nanoparticles in a 10 μL solution in an Eppendorf tube. The data indicates a drastically higher sample recovery of the Nano3 compared to the SP3 method for processing mass-limited proteome samples. In this pilot study, the Nano3 method was further applied in processing 10-1000 HeLa cells for bottom-up proteomics, producing 441 ± 263 (n = 4) (MS/MS) and 983 ± 292 (n = 4) [match between runs (MBR)+MS/MS] protein identifications from only 10 HeLa cells using a Q-Exactive HF mass spectrometer. The preliminary results render the Nano3 method a useful approach for processing few mammalian cells for proteome profiling.
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Affiliation(s)
- Zhichang Yang
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824 United States
| | - Zhaoran Zhang
- Department of Animal Sciences, Michigan State University, 766 Service Road, East Lansing, Michigan 48824 United States
| | - Daoyang Chen
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824 United States
| | - Tian Xu
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824 United States
| | - Yuan Wang
- Department of Animal Sciences, Michigan State University, 766 Service Road, East Lansing, Michigan 48824 United States
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824 United States
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10
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Zhang L, Xu T, Zhang J, Wong SCC, Ritchie M, Hou HW, Wang Y. Single Cell Metabolite Detection Using Inertial Microfluidics-Assisted Ion Mobility Mass Spectrometry. Anal Chem 2021; 93:10462-10468. [PMID: 34289696 DOI: 10.1021/acs.analchem.1c00106] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Single-cell metabolite measurement remains highly challenging due to difficulties related to single cell isolation, metabolite detection, and identification of low levels of metabolites. Here, as a first step of the technological development, we propose a novel strategy integrating spiral inertial microfluidics and ion mobility mass spectrometry (IM-MS) for single-cell metabolite detection and identification. Cells in methanol suspension are inertially focused into a single stream in the spiral microchannel. This stream of separated cells is delivered to the nanoelectrospray needle to be lysed and ionized and subsequently analyzed in real time by IM-MS. This analytical system enables six to eight single-cell metabolic fingerprints to be collected per minute, including gas-phase collisional cross section (CCS) measurements as an additional molecular descriptor, giving increased confidence in metabolite identification. As a proof of concept, the metabolic profiles of three types of cancer cells (U2OS, HepG2, and HepG2.215) were successfully screened, and 19 distinct lipids species were identified with CCS value filtering. Furthermore, principal component analysis (PCA) showed differentiation of the three cancer cell lines, mainly due to cellular surface phospholipids. Taken together, our technology platform offers a simple and efficient method for single-cell lipid profiling, with additional ion mobility separation of lipids significantly improving the confidence toward identification of metabolites.
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Affiliation(s)
- Leicheng Zhang
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, 639798 Singapore
| | - Tengfei Xu
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798 Singapore
| | - Jingtao Zhang
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, 639798 Singapore
| | | | - Mark Ritchie
- Waters Pacific Pte Ltd, Science Park 2, 117528 Singapore
| | - Han Wei Hou
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, 639798 Singapore.,School of Mechanical & Aerospace Engineering, Nanyang Technological University, 639798 Singapore
| | - Yulan Wang
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, 639798 Singapore
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11
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Yang Z, Sun L. Recent technical progress in sample preparation and liquid-phase separation-mass spectrometry for proteomic analysis of mass-limited samples. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2021; 13:1214-1225. [PMID: 33629703 DOI: 10.1039/d1ay00171j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Mass spectrometry (MS)-based proteomics has enabled the identification and quantification of thousands of proteins from complex proteomes in a single experiment. However, its performance for mass-limited proteome samples (e.g., single cells and tissue samples from laser capture microdissection) is still not satisfying. The development of novel proteomic methodologies with better overall sensitivity is vital. During the last several years, substantial technical progress has been achieved for the preparation and liquid-phase separation-MS characterization of mass-limited proteome samples. In this review, we summarize recent technological progress of sample preparation, liquid chromatography (LC)-MS, capillary zone electrophoresis (CZE)-MS and MS instrumentation for bottom-up proteomics of trace biological samples, highlight some exciting applications of the novel techniques for single-cell proteomics, and provide a very brief perspective about the field at the end.
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Affiliation(s)
- Zhichang Yang
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, MI 48824, USA.
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, MI 48824, USA.
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12
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Kartsova L, Makeeva D, Kravchenko A, Moskvichev D, Polikarpova D. Capillary electrophoresis as a powerful tool for the analyses of bacterial samples. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2020.116110] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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13
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Zhang Y, Fu X, Ping G. Selective Enrichment of Low-abundance Compounds in a Mixture by Capillary Electrophoresis. J Chromatogr A 2020; 1635:461737. [PMID: 33253999 DOI: 10.1016/j.chroma.2020.461737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 10/23/2022]
Abstract
Recently, we developed a new approach for the selective enrichment of low-abundance compounds in biological samples by capillary electrophoresis. As a model test, the low-abundance compound lysozyme was successfully fractionated from a mixture containing high-abundance compound BSA (1:4500) using a custom-made apparatus. The feasibility of this approach for real complex biological samples was verified by rat serum, wherein three low-abundance proteins with high charge/mass ratios were detected.
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Affiliation(s)
- Yong Zhang
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China.
| | - Xia Fu
- Linyi Inspection and Testing Center, 276000, China
| | - Guichen Ping
- College of Science, Inner Mongolia Agricultural University, Hohhot China.
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14
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Gou MJ, Nys G, Cobraiville G, Demelenne A, Servais AC, Fillet M. Hyphenation of capillary zone electrophoresis with mass spectrometry for proteomic analysis: Optimization and comparison of two coupling interfaces. J Chromatogr A 2020; 1618:460873. [DOI: 10.1016/j.chroma.2020.460873] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 11/30/2022]
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15
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Zheng Y, Liu Z, Xing J, Zheng Z, Pi Z, Song F, Liu S. In situ analysis of single cell and biological samples with rGO-Cu functional probe ESI-MS spectrometry. Talanta 2020; 211:120751. [DOI: 10.1016/j.talanta.2020.120751] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 01/12/2020] [Accepted: 01/14/2020] [Indexed: 01/17/2023]
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16
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DeLaney K, Li L. Capillary electrophoresis coupled to MALDI mass spectrometry imaging with large volume sample stacking injection for improved coverage of C. borealis neuropeptidome. Analyst 2019; 145:61-69. [PMID: 31723949 PMCID: PMC6917920 DOI: 10.1039/c9an01883b] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Neuropeptides are important signaling molecules responsible for a wide range of functions within the nervous and neuroendocrine system. However, they are difficult to study due to numerous challenges, most notably their large degree of variability and low abundance in vivo. As a result, effective separation methods with sensitive detection capabilities are necessary for profiling neuropeptides in tissue samples, particularly those of simplified model organisms such as crustaceans. In order to address these challenges, this study utilized a capillary electrophoresis (CE)-matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry imaging (MSI) platform, building upon our previous design for improved neuropeptidomic coverage. The capillary was coated with polyethylenimine (PEI) to reduce peptide adsorption and reverse the electroosmotic flow, and large volume sample stacking (LVSS) was used to load and pre-concentrate 1 μL of sample. The method demonstrated good reproducibility, with lower than 5% relative standard deviation for standards, and a limit of detection of approximately 100 pM for an allatostatin III peptide standard. The method was tested on brain and sinus gland (SG) tissue extracts and enabled detection of over 200 neuropeptides per run. When comparing the number detected in brain extracts in a direct spot, 60-second fractions, and 30-second fractions, the continuous trace collection afforded by the CE-MALDI-MSI platform yielded the largest number of detected neuropeptides. The method was compared to conventional LC-ESI-MS, and though the number of neuropeptides detected by LC-ESI-MS was slightly larger, the two methods were highly complementary, indicating the potential for the CE-MALDI-MSI method to uncover previously undetected neuropeptides in the crustacean nervous system. These results indicate the potential of CE-MALDI-MSI for routine use in neuropeptide research.
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Affiliation(s)
- Kellen DeLaney
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706-1322
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706-1322
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI 53705-2222
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17
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Gomes FP, Yates JR. Recent trends of capillary electrophoresis-mass spectrometry in proteomics research. MASS SPECTROMETRY REVIEWS 2019; 38:445-460. [PMID: 31407381 PMCID: PMC6800771 DOI: 10.1002/mas.21599] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Progress in proteomics research has led to a demand for powerful analytical tools with high separation efficiency and sensitivity for confident identification and quantification of proteins, posttranslational modifications, and protein complexes expressed in cells and tissues. This demand has significantly increased interest in capillary electrophoresis-mass spectrometry (CE-MS) in the past few years. This review provides highlights of recent advances in CE-MS for proteomics research, including a short introduction to top-down mass spectrometry and native mass spectrometry (native MS), as well as a detailed overview of CE methods. Both the potential and limitations of these methods for the analysis of proteins and peptides in synthetic and biological samples and the challenges of CE methods are discussed, along with perspectives about the future direction of CE-MS. @ 2019 Wiley Periodicals, Inc. Mass Spec Rev 00:1-16, 2019.
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Affiliation(s)
| | - John R. Yates
- Correspondent author: , Phone number: (858) 784-8862, Departments of Molecular Medicine and Neurobiology, 10550 North Torrey Pines Road, SR302B, The Scripps Research Institute, La Jolla, CA 92037
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Yang Z, Shen X, Chen D, Sun L. Improved Nanoflow RPLC-CZE-MS/MS System with High Peak Capacity and Sensitivity for Nanogram Bottom-up Proteomics. J Proteome Res 2019; 18:4046-4054. [PMID: 31610113 DOI: 10.1021/acs.jproteome.9b00545] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Novel mass spectrometry (MS)-based proteomic tools with extremely high sensitivity and high peak capacity are required for comprehensive characterization of protein molecules in mass-limited samples. We reported a nanoRPLC-CZE-MS/MS system for deep bottom-up proteomics of low micrograms of human cell samples in previous work. In this work, we improved the sensitivity of the nanoRPLC-CZE-MS/MS system drastically via employing bovine serum albumin (BSA)-treated sample vials, improving the nanoRPLC fraction collection procedure, and using a short capillary for fast CZE separation. The improved nanoRPLC-CZE produced a peak capacity of 8500 for peptide separation. The improved system identified 6500 proteins from a MCF7 proteome digest starting with only 500 ng of peptides using a Q-Exactive HF mass spectrometer. The system produced a comparable number of protein identifications (IDs) to our previous system and the two-dimensional (2D) nanoRPLC-MS/MS system developed by Mann's group with 10-fold and 4-fold less sample consumption, respectively. We coupled the single-spot solid phase sample preparation (SP3) method to the improved nanoRPLC-CZE-MS/MS for bottom-up proteomics of 5000 HEK293T cells, resulting in 3689 protein IDs with the consumption of a peptide amount that corresponded to only roughly 1000 cells.
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Affiliation(s)
- Zhichang Yang
- Department of Chemistry , Michigan State University , 578 S Shaw Lane , East Lansing , Michigan 48824 , United States
| | - Xiaojing Shen
- Department of Chemistry , Michigan State University , 578 S Shaw Lane , East Lansing , Michigan 48824 , United States
| | - Daoyang Chen
- Department of Chemistry , Michigan State University , 578 S Shaw Lane , East Lansing , Michigan 48824 , United States
| | - Liangliang Sun
- Department of Chemistry , Michigan State University , 578 S Shaw Lane , East Lansing , Michigan 48824 , United States
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20
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Gahoual R, Leize-Wagner E, Houzé P, François YN. Revealing the potential of capillary electrophoresis/mass spectrometry: the tipping point. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33 Suppl 1:11-19. [PMID: 30022554 DOI: 10.1002/rcm.8238] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/04/2018] [Accepted: 07/11/2018] [Indexed: 06/08/2023]
Abstract
The hyphenation of capillary electrophoresis and mass spectrometry (CE/MS) remains a minor technique compared with liquid chromatography/mass spectrometry (LC/MS), which represents nowadays the standard instrumentation, regardless of its introduction thirty years ago. However, from a theoretical point of view, CE coupling should be quite favorable especially with electrospray ionization mass spectrometry (ESI-MS). At the time, the sensitivity provided by CE/MS was often limited, due to hyphenation requirements, which at some point appeared to disqualify CE/MS from benefiting from the performance gain driving the evolution of MS instruments. However, this context has been significantly modified in a matter of a few years. The development of innovative CE/MS interfacing systems has enabled an important improvement regarding sensitivity and reinforced robustness in order to provide an instrumentation accessible to the largest scientific community. Because of the unique selectivity delivered by the electrophoretic separation, CE/MS has proved to be particularly relevant for the analysis of biological molecules. The conjunction of these aspects is motivating the interest in CE/MS analysis and shows that CE/MS is mature enough to enrich the toolbox of analytical techniques for the analysis of complex biological samples. Here we discuss the characteristics of the major types of high-sensitivity CE/ESI-MS instrumentation and emphasize the late evolution and future positioning of CE/MS analysis for the characterization of biological molecules like peptides and proteins, through some pertinent applications.
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Affiliation(s)
- Rabah Gahoual
- Unité de Technologies Biologiques et Chimiques pour la Santé (UTCBS), Paris 5-CNRS UMR8258 Inserm U1022, Faculté de Pharmacie, Université Paris Descartes, Paris, France
| | - Emmanuelle Leize-Wagner
- Laboratoire de spectrométrie de masse des interactions et des systèmes (LSMIS), Unistra-CNRS UMR7140, Université de Strasbourg, Strasbourg, France
| | - Pascal Houzé
- Unité de Technologies Biologiques et Chimiques pour la Santé (UTCBS), Paris 5-CNRS UMR8258 Inserm U1022, Faculté de Pharmacie, Université Paris Descartes, Paris, France
- Laboratoire de Biochimie, Hôpital Universitaire Necker-Enfants malades, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Yannis-Nicolas François
- Laboratoire de spectrométrie de masse des interactions et des systèmes (LSMIS), Unistra-CNRS UMR7140, Université de Strasbourg, Strasbourg, France
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Wu H, Yi L, Wojcik R, Shi T, Tang K. A separation voltage polarity switching method for higher sample loading capacity and better separation resolution in transient capillary isotachophoresis separation. Analyst 2019; 144:454-462. [PMID: 30444223 DOI: 10.1039/c8an01779d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A separation voltage polarity switching transient capillary isotachophoresis (PS-tCITP) was developed to overcome a major sample loading volume limitation in transient capillary isotachophoresis (tCITP). The fundamental idea of PS-tCITP is to let sample ions move back and forth in a separation capillary during their initial isotachophoresis focusing stage by switching the polarity of the separation voltage, in order to both increase the sample loading volume and improve the separation efficiency as compared to the conventional tCITP method. The experimental evaluation of the novel PS-tCITP method by using two peptide standards at 2 μM concentration showed that the maximum sample loading volume could be increased from 45% of the total separation capillary volume in tCITP to 70% in PS-tCITP, which resulted in a more than 1.5 fold increase in the peptide peak intensity at a given length/volume of the separation capillary. Due to the consecutive focusing of sample volume from each polarity switching of the separation voltage, the separation time window at a given sample loading volume was also increased significantly in PS-tCITP as compared to tCITP. Experiment comparison between tCITP and PS-tCITP at 45% sample loading volume using the same setup showed that the migration time difference between the two peptide peaks increased from 0.3 min in tCITP to 0.363 min in PS-tCITP with similar peak widths and heights, resulting in roughly a 21% improvement in separation resolution. The performance advantages of PS-tCITP separation over tCITP separation were further verified by using a mixture of six peptide standards.
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Affiliation(s)
- Huanming Wu
- Faculty of Electrical Engineering and Computer Science, Ningbo University, Ningbo 315211, P. R. China
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Pero-Gascon R, Pont L, Sanz-Nebot V, Benavente F. On-Line Immunoaffinity Solid-Phase Extraction Capillary Electrophoresis-Mass Spectrometry for the Analysis of Serum Transthyretin. Methods Mol Biol 2019; 1972:57-76. [PMID: 30847784 DOI: 10.1007/978-1-4939-9213-3_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The analysis of low abundant proteins in biological fluids by capillary electrophoresis (CE) is particularly problematic due to the typically poor concentration limits of detection of microscale separation techniques. Another important issue is sample matrix complexity that requires an appropriate cleanup. Here, we describe an on-line immunoaffinity solid-phase extraction capillary electrophoresis-mass spectrometry (IA-SPE-CE-MS) method for the immunoextraction, preconcentration, separation, detection, and characterization of serum transthyretin (TTR). TTR is a protein biomarker related to diverse types of amyloidosis, such as familial amyloidotic polyneuropathy type I (FAP-I), which is the most common hereditary systemic amyloidosis.
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Affiliation(s)
- Roger Pero-Gascon
- Department of Chemical Engineering and Analytical Chemistry, Institute for Research on Nutrition and Food Safety (INSA·UB), University of Barcelona, Barcelona, Spain
| | - Laura Pont
- Department of Chemical Engineering and Analytical Chemistry, Institute for Research on Nutrition and Food Safety (INSA·UB), University of Barcelona, Barcelona, Spain
| | - Victoria Sanz-Nebot
- Department of Chemical Engineering and Analytical Chemistry, Institute for Research on Nutrition and Food Safety (INSA·UB), University of Barcelona, Barcelona, Spain.
| | - Fernando Benavente
- Department of Chemical Engineering and Analytical Chemistry, Institute for Research on Nutrition and Food Safety (INSA·UB), University of Barcelona, Barcelona, Spain
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DeLaney K, Sauer CS, Vu NQ, Li L. Recent Advances and New Perspectives in Capillary Electrophoresis-Mass Spectrometry for Single Cell "Omics". Molecules 2018; 24:molecules24010042. [PMID: 30583525 PMCID: PMC6337428 DOI: 10.3390/molecules24010042] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/20/2018] [Accepted: 12/21/2018] [Indexed: 12/31/2022] Open
Abstract
Accurate clinical therapeutics rely on understanding the metabolic responses of individual cells. However, the high level of heterogeneity between cells means that simply sampling from large populations of cells is not necessarily a reliable approximation of an individual cell's response. As a result, there have been numerous developments in the field of single-cell analysis to address this lack of knowledge. Many of these developments have focused on the coupling of capillary electrophoresis (CE), a separation technique with low sample consumption and high resolving power, and mass spectrometry (MS), a sensitive detection method for interrogating all ions in a sample in a single analysis. In recent years, there have been many notable advancements at each step of the single-cell CE-MS analysis workflow, including sampling, manipulation, separation, and MS analysis. In each of these areas, the combined improvements in analytical instrumentation and achievements of numerous researchers have served to drive the field forward to new frontiers. Consequently, notable biological discoveries have been made possible by the implementation of these methods. Although there is still room in the field for numerous further advances, researchers have effectively minimized various limitations in detection of analytes, and it is expected that there will be many more developments in the near future.
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Affiliation(s)
- Kellen DeLaney
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA.
| | - Christopher S Sauer
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA.
| | - Nhu Q Vu
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA.
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA.
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI 53705, USA.
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24
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Pandeswari PB, Sabareesh V. Middle-down approach: a choice to sequence and characterize proteins/proteomes by mass spectrometry. RSC Adv 2018; 9:313-344. [PMID: 35521579 PMCID: PMC9059502 DOI: 10.1039/c8ra07200k] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 12/11/2018] [Indexed: 12/27/2022] Open
Abstract
Owing to rapid growth in the elucidation of genome sequences of various organisms, deducing proteome sequences has become imperative, in order to have an improved understanding of biological processes. Since the traditional Edman method was unsuitable for high-throughput sequencing and also for N-terminus modified proteins, mass spectrometry (MS) based methods, mainly based on soft ionization modes: electrospray ionization and matrix-assisted laser desorption/ionization, began to gain significance. MS based methods were adaptable for high-throughput studies and applicable for sequencing N-terminus blocked proteins/peptides too. Consequently, over the last decade a new discipline called 'proteomics' has emerged, which encompasses the attributes necessary for high-throughput identification of proteins. 'Proteomics' may also be regarded as an offshoot of the classic field, 'biochemistry'. Many protein sequencing and proteomic investigations were successfully accomplished through MS dependent sequence elucidation of 'short proteolytic peptides (typically: 7-20 amino acid residues), which is called the 'shotgun' or 'bottom-up (BU)' approach. While the BU approach continues as a workhorse for proteomics/protein sequencing, attempts to sequence intact proteins without proteolysis, called the 'top-down (TD)' approach started, due to ambiguities in the BU approach, e.g., protein inference problem, identification of proteoforms and the discovery of posttranslational modifications (PTMs). The high-throughput TD approach (TD proteomics) is yet in its infancy. Nevertheless, TD characterization of purified intact proteins has been useful for detecting PTMs. With the hope to overcome the pitfalls of BU and TD strategies, another concept called the 'middle-down (MD)' approach was put forward. Similar to BU, the MD approach also involves proteolysis, but in a restricted manner, to produce 'longer' proteolytic peptides than the ones usually obtained in BU studies, thereby providing better sequence coverage. In this regard, special proteases (OmpT, Sap9, IdeS) have been used, which can cleave proteins to produce longer proteolytic peptides. By reviewing ample evidences currently existing in the literature that is predominantly on PTM characterization of histones and antibodies, herein we highlight salient features of the MD approach. Consequently, we are inclined to claim that the MD concept might have widespread applications in future for various research areas, such as clinical, biopharmaceuticals (including PTM analysis) and even for general/routine characterization of proteins including therapeutic proteins, but not just limited to analysis of histones or antibodies.
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Affiliation(s)
- P Boomathi Pandeswari
- Advanced Centre for Bio Separation Technology (CBST), Vellore Institute of Technology (VIT) Vellore Tamil Nadu 632014 India
| | - Varatharajan Sabareesh
- Advanced Centre for Bio Separation Technology (CBST), Vellore Institute of Technology (VIT) Vellore Tamil Nadu 632014 India
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26
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Zhang Z, Hebert AS, Westphall MS, Qu Y, Coon JJ, Dovichi NJ. Production of Over 27 000 Peptide and Nearly 4400 Protein Identifications by Single-Shot Capillary-Zone Electrophoresis-Mass Spectrometry via Combination of a Very-Low-Electroosmosis Coated Capillary, a Third-Generation Electrokinetically-Pumped Sheath-Flow Nanospray Interface, an Orbitrap Fusion Lumos Tribrid Mass Spectrometer, and an Advanced-Peak-Determination Algorithm. Anal Chem 2018; 90:12090-12093. [PMID: 30179504 DOI: 10.1021/acs.analchem.8b02991] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We show that capillary-zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) generates very large numbers of peptide and protein identifications (IDs) by combining four technologies: a separation capillary coated to generate very low electroosmosis, an electrokinetically pumped sheath-flow nanoelectrospray interface to produce high-sensitivity ionization, an Orbitrap Fusion Lumos Tribrid platform to provide high-speed analysis, and an advanced-peak-determination (APD) algorithm to take advantage of the mass spectrometer's data-acquisition speed. The use of the APD algorithm resulted in 2 times more identifications than the standard peak algorithm. We also investigated the effect of the isolation window, injection time, and loading amount. Optimization of these parameters produced over 27 000 peptide identifications and nearly 4400 protein-group identifications from 220 ng of K562-cell digest in a single 120 min run, which is 2.7 times more IDs produced by CZE-ESI-MS/MS than by the previous state-of-the-art technique.
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Affiliation(s)
- Zhenbin Zhang
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Alexander S Hebert
- Department of Biomolecular Chemistry, Genome Center of Wisconsin, and Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States
| | - Michael S Westphall
- Department of Biomolecular Chemistry, Genome Center of Wisconsin, and Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States
| | - Yanyan Qu
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Joshua J Coon
- Department of Biomolecular Chemistry, Genome Center of Wisconsin, and Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
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27
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Yang Z, Shen X, Chen D, Sun L. Microscale Reversed-Phase Liquid Chromatography/Capillary Zone Electrophoresis-Tandem Mass Spectrometry for Deep and Highly Sensitive Bottom-Up Proteomics: Identification of 7500 Proteins with Five Micrograms of an MCF7 Proteome Digest. Anal Chem 2018; 90:10479-10486. [PMID: 30102516 PMCID: PMC6156779 DOI: 10.1021/acs.analchem.8b02466] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Capillary zone electrophoresis-tandem mass spectrometry (CZE-MS/MS) has been well recognized for bottom-up proteomics. It has approached 4000-8000 protein identifications (IDs) from a human cell line, mouse brains, or Xenopus embryos via coupling with liquid chromatography (LC) prefractionation. However, at least 500 μg of complex proteome digests were required for the LC/CZE-MS/MS studies. This requirement of a large amount of initial peptide material impedes the application of CZE-MS/MS for deep bottom-up proteomics of mass-limited samples. In this work, we coupled microscale reversed-phase LC (μRPLC)-based peptide prefractionation to dynamic pH-junction-based CZE-MS/MS for deep bottom-up proteomics of the MCF7 breast cancer cell proteome starting with only 5 μg of peptides. The dynamic pH-junction-based CZE enabled a 500 nL sample injection from as low as a 1.5 μL peptide sample, using up to 33% of the available peptide material for an analysis. Two kinds of μRPLC prefractionation were investigated, C18 ZipTip and nanoflow RPLC. C18 ZipTip/CZE-MS/MS identified 4453 proteins from 5 μg of the MCF7 proteome digest and showed good qualitative and quantitative reproducibility. Nanoflow RPLC/CZE-MS/MS produced over 7500 protein IDs and nearly 60 000 peptide IDs from the 5 μg of MCF7 proteome digest. The nanoflow RPLC/CZE-MS/MS platform reduced the required amount of complex proteome digests for LC/CZE-MS/MS-based deep bottom-up proteomics by 2 orders of magnitude. Our work provides the proteomics community with a powerful tool for deep and highly sensitive proteomics.
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Affiliation(s)
- Zhichang Yang
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824 USA
| | - Xiaojing Shen
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824 USA
| | - Daoyang Chen
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824 USA
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824 USA
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28
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Chen D, Shen X, Sun L. Strong cation exchange-reversed phase liquid chromatography-capillary zone electrophoresis-tandem mass spectrometry platform with high peak capacity for deep bottom-up proteomics. Anal Chim Acta 2018; 1012:1-9. [PMID: 29475469 DOI: 10.1016/j.aca.2018.01.037] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Revised: 01/19/2018] [Accepted: 01/22/2018] [Indexed: 11/29/2022]
Abstract
Two-dimensional (2D) liquid chromatography (LC)-tandem mass spectrometry (MS/MS) are typically employed for deep bottom-up proteomics, and the state-of-the-art 2D-LC-MS/MS has approached over 8000 protein identifications (IDs) from mammalian cell lines or tissues in 1-3 days of mass spectrometer time. Capillary zone electrophoresis (CZE)-MS/MS has been suggested as an alternative to LC-MS/MS for bottom-up proteomics. CZE-MS/MS and LC-MS/MS are complementary in protein/peptide ID from complex proteome digests because CZE and LC are orthogonal for peptide separation. In addition, the migration time of peptides from CZE-MS can be predicted accurately, which is invaluable for evaluating the confidence of peptide ID from the database search and even guiding the database search. However, the number of protein IDs from complex proteomes using CZE-MS/MS is still much lower than the state of the art using 2D-LC-MS/MS. In this work, for the first time, we established a strong cation exchange (SCX)-reversed phase LC (RPLC)-CZE-MS/MS platform for deep bottom-up proteomics. The platform identified around 8200 protein groups and 65,000 unique peptides from a mouse brain proteome digest in 70 h. The data represents the largest bottom-up proteomics dataset using CZE-MS/MS and provides a valuable resource for further improving the tool for prediction of peptide migration time in CZE. The peak capacity of the orthogonal SCX-RPLC-CZE platform was estimated to be around 7000. SCX-RPLC-CZE-MS/MS produced comparable numbers of protein and peptide IDs with 2D-LC-MS/MS (8200 vs. 8900 protein groups, 65,000 vs. 70,000 unique peptides) from the mouse brain proteome digest using comparable instrument time. This is the first time that CZE-MS/MS showed its capability to approach comparable performance to the state-of-the-art 2D-LC-MS/MS for deep proteomic sequencing. SCX-RPLC-CZE-MS/MS and 2D-LC-MS/MS showed good complementarity in protein and peptide IDs and combining those two methods improved the number of protein group and unique peptide IDs by nearly 10% and over 40%, respectively, compared with 2D-LC-MS/MS alone.
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Affiliation(s)
- Daoyang Chen
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824, USA
| | - Xiaojing Shen
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824, USA
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, 578 S Shaw Ln, East Lansing, MI 48824, USA.
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29
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Huang Q, Mao S, Khan M, Zhou L, Lin JM. Dean flow assisted cell ordering system for lipid profiling in single-cells using mass spectrometry. Chem Commun (Camb) 2018; 54:2595-2598. [DOI: 10.1039/c7cc09608a] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A Dean flow assisted ordering system connected to an ESI-MS to identify single-cells in a subpopulation by lipid profiling.
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Affiliation(s)
- Qiushi Huang
- Department of Chemistry, Beijing Key Laboratory of Micronalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
- Beijing 100084
- China
| | - Sifeng Mao
- Department of Chemistry, Beijing Key Laboratory of Micronalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
- Beijing 100084
- China
| | - Mashooq Khan
- Department of Chemistry, Beijing Key Laboratory of Micronalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
- Beijing 100084
- China
| | - Lin Zhou
- Department of Chemistry, Beijing Key Laboratory of Micronalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
- Beijing 100084
- China
| | - Jin-Ming Lin
- Department of Chemistry, Beijing Key Laboratory of Micronalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
- Beijing 100084
- China
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30
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Zhang Z, Dovichi NJ. Optimization of mass spectrometric parameters improve the identification performance of capillary zone electrophoresis for single-shot bottom-up proteomics analysis. Anal Chim Acta 2017; 1001:93-99. [PMID: 29291811 DOI: 10.1016/j.aca.2017.11.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 11/02/2017] [Accepted: 11/07/2017] [Indexed: 12/23/2022]
Abstract
The effects of MS1 injection time, MS2 injection time, dynamic exclusion time, intensity threshold, and isolation width were investigated on the numbers of peptide and protein identifications for single-shot bottom-up proteomics analysis using CZE-MS/MS analysis of a Xenopus laevis tryptic digest. An electrokinetically pumped nanospray interface was used to couple a linear-polyacrylamide coated capillary to a Q Exactive HF mass spectrometer. A sensitive method that used a 1.4 Th isolation width, 60,000 MS2 resolution, 110 ms MS2 injection time, and a top 7 fragmentation produced the largest number of identifications when the CZE loading amount was less than 100 ng. A programmable autogain control method (pAGC) that used a 1.4 Th isolation width, 15,000 MS2 resolution, 110 ms MS2 injection time, and top 10 fragmentation produced the largest number of identifications for CZE loading amounts greater than 100 ng; 7218 unique peptides and 1653 protein groups were identified from 200 ng by using the pAGC method. The effect of mass spectrometer conditions on the performance of UPLC-MS/MS was also investigated. A fast method that used a 1.4 Th isolation width, 30,000 MS2 resolution, 45 ms MS2 injection time, and top 12 fragmentation produced the largest number of identifications for 200 ng UPLC loading amount (6025 unique peptides and 1501 protein groups). This is the first report where the identification number for CZE surpasses that of the UPLC at the 200 ng loading level. However, more peptides (11476) and protein groups (2378) were identified by using UPLC-MS/MS when the sample loading amount was increased to 2 μg with the fast method. To exploit the fast scan speed of the Q-Exactive HF mass spectrometer, higher sample loading amounts are required for single-shot bottom-up proteomics analysis using CZE-MS/MS.
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Affiliation(s)
- Zhenbin Zhang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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31
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Yi L, Piehowski PD, Shi T, Smith RD, Qian WJ. Advances in microscale separations towards nanoproteomics applications. J Chromatogr A 2017; 1523:40-48. [PMID: 28765000 PMCID: PMC6042839 DOI: 10.1016/j.chroma.2017.07.055] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 07/14/2017] [Accepted: 07/17/2017] [Indexed: 01/22/2023]
Abstract
Microscale separation (e.g., liquid chromatography or capillary electrophoresis) coupled with mass spectrometry (MS) has become the primary tool for advanced proteomics, an indispensable technology for gaining understanding of complex biological processes. In recent decades significant advances have been achieved in MS-based proteomics. However, the current proteomics platforms still face an analytical challenge in overall sensitivity towards nanoproteomics applications for starting materials of less than 1μg total proteins (e.g., cellular heterogeneity in tissue pathologies). Herein, we review recent advances in microscale separation techniques and integrated sample processing strategies that improve the overall sensitivity and proteome coverage of the proteomics workflow, and their contributions towards nanoproteomics applications.
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Affiliation(s)
- Lian Yi
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Paul D Piehowski
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Tujin Shi
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Richard D Smith
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Wei-Jun Qian
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States.
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32
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Jansson ET. Strategies for analysis of isomeric peptides. J Sep Sci 2017; 41:385-397. [PMID: 28922569 DOI: 10.1002/jssc.201700852] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/06/2017] [Accepted: 09/06/2017] [Indexed: 01/09/2023]
Abstract
This review presents an overview and recent progress of strategies for detecting isomerism in peptides, with focus on d/l epimerization and the various isomers that the presence of an aspartic acid residue may yield in a protein or peptide. While mass spectrometry has become a majorly used method of choice within proteomics, isomerism is inherently difficult to analyze because it is a modification that does not yield any change in mass of the analyte. Here, several techniques used for analysis of peptide isomerism are discussed, including enzymatic assays, liquid chromatography, and capillary electrophoresis. Recent progress in method development using mass spectrometry is also discussed, including labeling strategies, fragmentation techniques, and ion-mobility spectrometry.
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Affiliation(s)
- Erik T Jansson
- Department of Chemistry-BMC, Uppsala University, Uppsala, Sweden
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33
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Stewart PA, Fang B, Slebos RJC, Zhang G, Borne AL, Fellows K, Teer JK, Chen YA, Welsh E, Eschrich SA, Haura EB, Koomen JM. Relative protein quantification and accessible biology in lung tumor proteomes from four LC-MS/MS discovery platforms. Proteomics 2017; 17. [PMID: 28195392 DOI: 10.1002/pmic.201600300] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 01/31/2017] [Accepted: 02/03/2017] [Indexed: 01/01/2023]
Abstract
Discovery proteomics experiments include many options for sample preparation and MS data acquisition, which are capable of creating datasets for quantifying thousands of proteins. To define a strategy that would produce a dataset with sufficient content while optimizing required resources, we compared (1) single-sample LC-MS/MS with data-dependent acquisition to single-sample LC-MS/MS with data-independent acquisition and (2) peptide fractionation with label-free (LF) quantification to peptide fractionation with relative quantification of chemically labeled peptides (sixplex tandem mass tags (TMT)). These strategies were applied to the same set of four frozen lung squamous cell carcinomas and four adjacent tissues, and the overall outcomes of each experiment were assessed. We identified 6656 unique protein groups with LF, 5535 using TMT, 3409 proteins from single-sample analysis with data-independent acquisition, and 2219 proteins from single-sample analysis with data-dependent acquisition. Pathway analysis indicated the number of proteins per pathway was proportional to the total protein identifications from each method, suggesting limited biological bias between experiments. The results suggest the use of single-sample experiments as a rapid tissue assessment tool and digestion quality control or as a technique to maximize output from limited samples and use of TMT or LF quantification as methods for larger amounts of tumor tissue with the selection being driven mainly by instrument time limitations. Data are available via ProteomeXchange with identifiers PXD004682, PXD004683, PXD004684, and PXD005733.
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Affiliation(s)
- Paul A Stewart
- Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Bin Fang
- Proteomics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Robbert J C Slebos
- Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Guolin Zhang
- Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Adam L Borne
- Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Katherine Fellows
- Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Jamie K Teer
- Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Y Ann Chen
- Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Eric Welsh
- Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Steven A Eschrich
- Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Eric B Haura
- Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - John M Koomen
- Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
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34
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Yan X, Sun L, Zhu G, Cox OF, Dovichi NJ. Over 4100 protein identifications from a Xenopus laevis fertilized egg digest using reversed-phase chromatographic prefractionation followed by capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry analysis. Proteomics 2017; 16:2945-2952. [PMID: 27723263 DOI: 10.1002/pmic.201600262] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 09/14/2016] [Accepted: 10/07/2016] [Indexed: 12/25/2022]
Abstract
A tryptic digest generated from Xenopus laevis fertilized embryos was fractionated by RPLC. One set of 30 fractions was analyzed by 100-min CZE-ESI-MS/MS separations (50 h total instrument time), and a second set of 15 fractions was analyzed by 3-h UPLC-ESI-MS/MS separations (45 h total instrument time). CZE-MS/MS produced 70% as many protein IDs (4134 versus 5787) and 60% as many peptide IDs (22 535 versus 36 848) as UPLC-MS/MS with similar instrument time (50 h versus 45 h) but with 50 times smaller total consumed sample amount (1.5 μg versus 75 μg). Surprisingly, CZE generated peaks that were 25% more intense than UPLC for peptides that were identified by both techniques, despite the 50-fold lower loading amount; this high sensitivity reflects the efficient ionization produced by the electrokinetically pumped nanospray interface used in CZE. This report is the first comparison of CZE-MS/MS and UPLC-MS/MS for large-scale eukaryotic proteomic analysis. The numbers of protein and peptide identifications produced by CZE-ESI-MS/MS approach those produced by UPLC-MS/MS, but with nearly two orders of magnitude lower sample amounts.
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Affiliation(s)
- Xiaojing Yan
- Department of Chemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Liangliang Sun
- Department of Chemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Guijie Zhu
- Department of Chemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Olivia F Cox
- Department of Chemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Norman J Dovichi
- Department of Chemistry, University of Notre Dame, Notre Dame, IN, USA
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35
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Jiang Y, He MY, Zhang WJ, Luo P, Guo D, Fang X, Xu W. Recent advances of capillary electrophoresis-mass spectrometry instrumentation and methodology. CHINESE CHEM LETT 2017. [DOI: 10.1016/j.cclet.2017.05.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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36
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Boley DA, Zhang Z, Dovichi NJ. Multisegment injections improve peptide identification rates in capillary zone electrophoresis-based bottom-up proteomics. J Chromatogr A 2017; 1523:123-126. [PMID: 28732593 DOI: 10.1016/j.chroma.2017.07.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 07/05/2017] [Accepted: 07/06/2017] [Indexed: 02/03/2023]
Abstract
While capillary zone electrophoresis (CZE) provides dramatically improved numbers of peptide identifications compared with reversed-phase chromatography for bottom-up proteomics of mass limited samples, CZE inevitably produces lower numbers of peptide identifications than RPLC for larger samples. One reason for this poorer performance is the dead time between injection of samples and subsequent appearance of the fastest moving component. This dead time is typically 25% of the separation window in CZE, but is only 5% of the separation window in gradient elution RPLC. This dead time can be eliminated in CZE by use of a multisegment injection mode where a series of samples is analyzed by injecting each sample while the preceding sample is still being separated. In this paper, we demonstrate that capillary zone electrophoresis employing sequential injections can produce a doubling in peptide identification rate with no degradation in separation efficiency.
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Affiliation(s)
- Danielle A Boley
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Zhenbin Zhang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.
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37
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Zhang Z, Peuchen EH, Dovichi NJ. Surface-Confined Aqueous Reversible Addition-Fragmentation Chain Transfer (SCARAFT) Polymerization Method for Preparation of Coated Capillary Leads to over 10 000 Peptides Identified from 25 ng HeLa Digest by Using Capillary Zone Electrophoresis-Tandem Mass Spectrometry. Anal Chem 2017; 89:6774-6780. [PMID: 28540730 DOI: 10.1021/acs.analchem.7b01147] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A surface-confined aqueous reversible addition-fragmentation chain transfer (SCARAFT) polymerization method was developed to coat capillaries for use in capillary zone electrophoresis (CZE). SCARAFT polymerization primarily takes place on the inner surface of the capillary instead of in solution, which greatly improves the homogeneity of the coating. Capillaries treated with this coating produced an electroosmotic mobility of 2.8 ± 0.2 × 10-6 cm2·V-1·s-1 (N = 3), which is roughly an order of magnitude lower than that of commercial linear polyacrylamide (LPA)-coated capillaries. Coated capillaries were evaluated for bottom-up proteomic analysis using CZE. The very low electroosmotic mobility results in a 200 min separation and improved single-shot analysis. An average of 977 protein groups and 5605 unique peptides were identified from 50 ng of an E. coli digest, and 2158 protein groups and 10 005 peptides were identified from 25 ng of a HeLa digest using single-shot analysis with a SCARAFT-acrylamide capillary coupled to a Q Exactive HF mass spectrometer. The coating is stable. A single capillary was used for over 200 h (8.4 days) of continuous operation. RSD in migration time was between 2 and 3% for selected ion electropherograms (SIEs) generated for six ions; median theoretical plate counts ranged from 240 000 to 600 000 for these SIEs. Various types of coatings could be prepared by simply changing the functional vinyl monomers in the polymerization mixture. Positively charged coatings using direct attachment and formation of a block copolymer were prepared and demonstrated for the separation of mixtures of intact proteins.
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Affiliation(s)
- Zhenbin Zhang
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Elizabeth H Peuchen
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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38
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Biacchi M, Said N, Beck A, Leize-Wagner E, François YN. Top-down and middle-down approach by fraction collection enrichment using off-line capillary electrophoresis – mass spectrometry coupling: Application to monoclonal antibody F c/2 charge variants. J Chromatogr A 2017; 1498:120-127. [DOI: 10.1016/j.chroma.2017.02.064] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 01/13/2017] [Accepted: 02/26/2017] [Indexed: 12/22/2022]
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39
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Faserl K, Sarg B, Maurer V, Lindner HH. Exploiting charge differences for the analysis of challenging post-translational modifications by capillary electrophoresis-mass spectrometry. J Chromatogr A 2017; 1498:215-223. [DOI: 10.1016/j.chroma.2017.01.086] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 01/25/2017] [Accepted: 01/29/2017] [Indexed: 12/27/2022]
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40
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Chen D, Shen X, Sun L. Capillary zone electrophoresis–mass spectrometry with microliter-scale loading capacity, 140 min separation window and high peak capacity for bottom-up proteomics. Analyst 2017; 142:2118-2127. [DOI: 10.1039/c7an00509a] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
CZE–MS can approach a microliter-scale loading capacity and a 140 min separation window for large-scale bottom-up proteomics.
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Affiliation(s)
- Daoyang Chen
- Department of Chemistry
- Michigan State University
- East Lansing
- USA 48824
| | - Xiaojing Shen
- Department of Chemistry
- Michigan State University
- East Lansing
- USA 48824
| | - Liangliang Sun
- Department of Chemistry
- Michigan State University
- East Lansing
- USA 48824
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41
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KAWAI T. Recent Studies on Online Sample Preconcentration Methods inCapillary Electrophoresis Coupled with Mass Spectrometry. CHROMATOGRAPHY 2017. [DOI: 10.15583/jpchrom.2017.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Takayuki KAWAI
- Quantitative Biology Center, RIKEN
- Japan Science and Technology Agency, PRESTO
- Graduate School of Frontier Biosciences, Osaka University
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42
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Zhu G, Sun L, Heidbrink-Thompson J, Kuntumalla S, Lin HY, Larkin CJ, McGivney JB, Dovichi NJ. Capillary zone electrophoresis tandem mass spectrometry detects low concentration host cell impurities in monoclonal antibodies. Electrophoresis 2016; 37:616-22. [PMID: 26530276 DOI: 10.1002/elps.201500301] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 10/02/2015] [Accepted: 10/27/2015] [Indexed: 12/22/2022]
Abstract
We have evaluated CZE-ESI-MS/MS for detection of trace amounts of host cell protein impurities in recombinant therapeutics. Compared to previously published procedures, we have optimized the buffer pH used in the formation of a pH junction to increase injection volume. We also prepared a 5-point calibration curve by spiking 12 standard proteins into a solution of a human mAb. A custom CZE-MS/MS system was used to analyze the tryptic digest of this mixture without depletion of the antibody. CZE generated a ∼70-min separation window (∼90-min total analysis duration) and ∼300-peak capacity. We also analyzed the sample using ultra-performance LC-MS/MS. CZE-MS/MS generated approximately five times higher base peak intensity and more peptide identifications for low-level spiked proteins. Both methods detected all proteins spiked at ∼100 ppm level with respect to the antibody.
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Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | | | | | - Hung-yu Lin
- Department of Analytical Biotechnology, MedImmune, Gaithersburg, MD, USA
| | | | - James B McGivney
- Department of Analytical Biotechnology, MedImmune, Gaithersburg, MD, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
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43
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Yuan F, Zhang XH, Nie J, Chen HX, Zhou YL, Zhang XX. Ultrasensitive determination of 5-methylcytosine and 5-hydroxymethylcytosine in genomic DNA by sheathless interfaced capillary electrophoresis-mass spectrometry. Chem Commun (Camb) 2016; 52:2698-700. [PMID: 26753520 DOI: 10.1039/c5cc10155g] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A newly developed sheathless interface for capillary electrophoresis-mass spectrometry, using a porous tip sprayer, was first applied for highly sensitive determination of cytosine modifications. The system performed well in identification and quantification of both 5-methylcytosine and 5-hydroxymethylcytosine using only 125 pg (∼20 cells) genomic DNA samples.
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Affiliation(s)
- Fang Yuan
- Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry, Peking University, Beijing 100871, China.
| | - Xiao-Hui Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry, Peking University, Beijing 100871, China.
| | - Ji Nie
- Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry, Peking University, Beijing 100871, China.
| | - Hong-Xu Chen
- Shanghai AB Sciex Analytical Instrument Trading Co., Ltd, Beijing, P. R. China
| | - Ying-Lin Zhou
- Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry, Peking University, Beijing 100871, China.
| | - Xin-Xiang Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry, Peking University, Beijing 100871, China.
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44
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Zhao Y, Sun L, Zhu G, Dovichi NJ. Coupling Capillary Zone Electrophoresis to a Q Exactive HF Mass Spectrometer for Top-down Proteomics: 580 Proteoform Identifications from Yeast. J Proteome Res 2016; 15:3679-3685. [PMID: 27490796 DOI: 10.1021/acs.jproteome.6b00493] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We used reversed-phase liquid chromatography to separate the yeast proteome into 23 fractions. These fractions were then analyzed using capillary zone electrophoresis (CZE) coupled to a Q-Exactive HF mass spectrometer using an electrokinetically pumped sheath flow interface. The parameters of the mass spectrometer were first optimized for top-down proteomics using a mixture of seven model proteins; we observed that intact protein mode with a trapping pressure of 0.2 and normalized collision energy of 20% produced the highest intact protein signals and most protein identifications. Then, we applied the optimized parameters for analysis of the fractionated yeast proteome. From this, 580 proteoforms and 180 protein groups were identified via database searching of the MS/MS spectra. This number of proteoform identifications is two times larger than that of previous CZE-MS/MS studies. An additional 3,243 protein species were detected based on the parent ion spectra. Post-translational modifications including N-terminal acetylation, signal peptide removal, and oxidation were identified.
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Affiliation(s)
- Yimeng Zhao
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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45
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Zhu G, Sun L, Dovichi NJ. Dynamic pH junction preconcentration in capillary electrophoresis- electrospray ionization-mass spectrometry for proteomics analysis. Analyst 2016; 141:5216-20. [PMID: 27460877 DOI: 10.1039/c6an01140c] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Capillary zone electrophoresis (CZE)-electrospray ionization (ESI)-mass spectrometry (MS) is an interesting complimentary technique to reversed phase liquid chromatography (RPLC)-ESI-MS for proteomics research. However, the low sample loading capacity of CZE (typically a few nL) can limit its application for large-scale proteomics. A number of on-line sample preconcentration methods have been developed to increase sample loading volumes. This review considers the dynamic pH junction as a simple on-line sample preconcentration method; this method is well suited for amphiprotic analytes. In the pH junction, these analytes are suspended in a basic buffer, injected by pressure into the capillary, and separated in an acidic background electrolyte, with no changes in either CZE-MS operations or instrumentation. We have demonstrated that the dynamic pH junction method can improve the sample loading volume to sub-μL volumes without significant loss of separation capacity for bottom-up proteomic analysis. The dynamic pH junction based CZE-ESI-MS system has been applied for a number of complex biological samples, including the E. coli proteome, impurities in recombinant antibody therapeutics, and the characterization of the phosphoproteome from a human cell line.
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Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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46
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Ibrahim M, Gahoual R, Enkler L, Becker HD, Chicher J, Hammann P, François YN, Kuhn L, Leize-Wagner E. Improvement of Mitochondria Extract from Saccharomyces cerevisiae Characterization in Shotgun Proteomics Using Sheathless Capillary Electrophoresis Coupled to Tandem Mass Spectrometry. J Chromatogr Sci 2016; 54:653-63. [PMID: 26860395 PMCID: PMC4885408 DOI: 10.1093/chromsci/bmw005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 12/11/2015] [Indexed: 12/16/2022]
Abstract
In this work, we describe the characterization of a quantity-limited sample (100 ng) of yeast mitochondria by shotgun bottom-up proteomics. Sample characterization was carried out by sheathless capillary electrophoresis, equipped with a high sensitivity porous tip and coupled to tandem mass spectrometry (CESI-MS-MS) and concomitantly with a state-of-art nano flow liquid chromatography coupled to a similar mass spectrometry (MS) system (nanoLC-MS-MS). With single injections, both nanoLC-MS-MS and CESI-MS-MS 60 min-long separation experiments allowed us to identify 271 proteins (976 unique peptides) and 300 proteins (1,765 unique peptides) respectively, demonstrating a significant specificity and complementarity in identification depending on the physicochemical separation employed. Such complementary, maximizing the number of analytes detected, presents a powerful tool to deepen a biological sample's proteomic characterization. A comprehensive study of the specificity provided by each separating technique was also performed using the different properties of the identified peptides: molecular weight, mass-to-charge ratio (m/z), isoelectric point (pI), sequence coverage or MS-MS spectral quality enabled to determine the contribution of each separation. For example, CESI-MS-MS enables to identify larger peptides and eases the detection of those having extreme pI without impairing spectral quality. The addition of peptides, and therefore proteins identified by both techniques allowed us to increase significantly the sequence coverages and then the confidence of characterization. In this study, we also demonstrated that the two yeast enolase isoenzymes were both characterized in the CESI-MS-MS data set. The observation of discriminant proteotypic peptides is facilitated when a high number of precursors with high-quality MS-MS spectra are generated.
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Affiliation(s)
- Marianne Ibrahim
- Laboratoire de Spectrométrie de Masse des Interactions et des Systèmes (LSMIS), UDS-CNRS UMR 7140, Université de Strasbourg, 67008 Strasbourg, France
| | - Rabah Gahoual
- Laboratoire de Spectrométrie de Masse des Interactions et des Systèmes (LSMIS), UDS-CNRS UMR 7140, Université de Strasbourg, 67008 Strasbourg, France
| | - Ludovic Enkler
- Unité Mixte de Recherche 7156 Génétique Moléculaire Génomique Microbiologie, Centre National de la Recherche Scientifique, Université de Strasbourg, 67084 Strasbourg, France
| | - Hubert Dominique Becker
- Unité Mixte de Recherche 7156 Génétique Moléculaire Génomique Microbiologie, Centre National de la Recherche Scientifique, Université de Strasbourg, 67084 Strasbourg, France
| | - Johana Chicher
- Plateforme Protéomique Strasbourg-Esplanade, Institut de Biologie Moléculaire et Cellulaire, FRC 1589, Centre National de la Recherche Scientifique, Université de Strasbourg, 67084 Strasbourg, France
| | - Philippe Hammann
- Plateforme Protéomique Strasbourg-Esplanade, Institut de Biologie Moléculaire et Cellulaire, FRC 1589, Centre National de la Recherche Scientifique, Université de Strasbourg, 67084 Strasbourg, France
| | - Yannis-Nicolas François
- Laboratoire de Spectrométrie de Masse des Interactions et des Systèmes (LSMIS), UDS-CNRS UMR 7140, Université de Strasbourg, 67008 Strasbourg, France
| | - Lauriane Kuhn
- Plateforme Protéomique Strasbourg-Esplanade, Institut de Biologie Moléculaire et Cellulaire, FRC 1589, Centre National de la Recherche Scientifique, Université de Strasbourg, 67084 Strasbourg, France
| | - Emmanuelle Leize-Wagner
- Laboratoire de Spectrométrie de Masse des Interactions et des Systèmes (LSMIS), UDS-CNRS UMR 7140, Université de Strasbourg, 67008 Strasbourg, France
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47
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Zhu G, Sun L, Dovichi NJ. Thermally-initiated free radical polymerization for reproducible production of stable linear polyacrylamide coated capillaries, and their application to proteomic analysis using capillary zone electrophoresis-mass spectrometry. Talanta 2016; 146:839-43. [PMID: 26695337 PMCID: PMC4690009 DOI: 10.1016/j.talanta.2015.06.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/01/2015] [Accepted: 06/02/2015] [Indexed: 02/03/2023]
Abstract
Proteomic analysis using capillary zone electrophoresis (CZE) typically is performed with linear polyacrylamide (LPA) coated capillaries. These capillaries both minimize the adsorption of peptides and proteins to the inner wall of the capillary and decrease electroosmosis, which increases the separation capacity. LPA coating protocols were first reported by Hjerten in 1985. Conventional LPA production is based on the use of tetramethylethylenediamine (TEMED) to catalyze the free-radical polymerization that couples acrylamide to a capillary wall that has been pretreated with γ-methacryloxypropyltrimethoxysilane. The treated capillary is filled with a mixture of monomer, TEMED, and ammonium persulfate; free radical polymerization forms the LPA coating. Over many years, we have observed significant variation in the electroosmotic properties of commercial LPA coated capillaries both along the capillary length and between lots. We believe this variation is due to differences in the time between initiation of the reaction and the filling of the capillary. Here, we report a simple method for the generation of very stable and reproducible coatings. In this protocol, the monomer mixture and an ammonium persulfate initiator are introduced into the capillary without TEMED initiator. The mixture is stable and does not begin polymerization at room temperature. The filled capillary is then heated in a water bath to initiate polymerization in a well-controlled manner. A mixture of four standard proteins was used to evaluate the coating performance. Compared with commercialized LPA capillaries, our LPA capillaries generate much better separation performance and superior protein peak shape in CZE analysis. We also analyzed an intact antibody (MW 150K) by CZE-MS with the new LPA capillary in triplicate runs. The intact antibody generated a Gaussian-shaped electrophoresis peak with 1.2% relative standard deviation in migration time and 8.5% in base peak intensity. An automated CZE-MS system was used to generate 97 successive separations of a BSA tryptic digest over a 145-h period. Separation efficiency averaged over 100,000 theoretical plates across this period with no systematic variation. The LPA coating protocol had excellent batch-to-batch reproducibility with relative standard deviation in migration time<7%, and in separation window<1%.
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Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, IN 46556, USA
| | - Liangliang Sun
- Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, IN 46556, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, IN 46556, USA
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48
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Sun L, Zhu G, Yan X, Zhang Z, Wojcik R, Champion MM, Dovichi NJ. Capillary zone electrophoresis for bottom-up analysis of complex proteomes. Proteomics 2015; 16:188-96. [PMID: 26508368 DOI: 10.1002/pmic.201500339] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 09/30/2015] [Accepted: 10/22/2015] [Indexed: 12/22/2022]
Abstract
Capillary zone electrophoresis (CZE) is emerging as a useful tool in proteomic analysis. Interest arises from dramatic improvements in performance that result from improvements in the background electrolyte used for the separation, the incorporation of advanced sample injection methods, the development of robust and sensitive electrospray interfaces, and the coupling with Orbitrap mass spectrometers with high resolution and sensitivity. The combination of these technologies produces performance that is rapidly approaching the performance of UPLC-based methods for microgram samples and exceeds the performance of UPLC-based methods for mid- to low nanogram samples. These systems now produce over 10 000 peptide IDs in a single 100-min analysis of the HeLa proteome.
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Affiliation(s)
- Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Xiaojing Yan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Zhenbin Zhang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Roza Wojcik
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Matthew M Champion
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
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Zhang Z, Sun L, Zhu G, Cox OF, Huber PW, Dovichi NJ. Nearly 1000 Protein Identifications from 50 ng of Xenopus laevis Zygote Homogenate Using Online Sample Preparation on a Strong Cation Exchange Monolith Based Microreactor Coupled with Capillary Zone Electrophoresis. Anal Chem 2015; 88:877-82. [PMID: 26670623 DOI: 10.1021/acs.analchem.5b03496] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A sulfonate-silica hybrid strong cation exchange monolith microreactor was synthesized and coupled to a linear polyacrylamide coated capillary for online sample preparation and capillary zone electrophoresis-tandem mass spectrometry (CZE-MS/MS) bottom-up proteomic analysis. The protein sample was loaded onto the microreactor in an acidic buffer. After online reduction, alkylation, and digestion with trypsin, the digests were eluted with 200 mM ammonium bicarbonate at pH 8.2 for CZE-MS/MS analysis using 1 M acetic acid as the background electrolyte. This combination of basic elution and acidic background electrolytes results in both sample stacking and formation of a dynamic pH junction. 369 protein groups and 1274 peptides were identified from 50 ng of Xenopus laevis zygote homogenate, which is comparable with an offline sample preparation method, but the time required for sample preparation was decreased from over 24 h to less than 40 min. Dramatically improved performance was produced by coupling the reactor to a longer separation capillary (∼100 cm) and a Q Exactive HF mass spectrometer. 975 protein groups and 3749 peptides were identified from 50 ng of Xenopus protein using the online sample preparation method.
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Affiliation(s)
- Zhenbin Zhang
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Olivia F Cox
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Paul W Huber
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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50
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Kašička V. Recent developments in capillary and microchip electroseparations of peptides (2013-middle 2015). Electrophoresis 2015; 37:162-88. [DOI: 10.1002/elps.201500329] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 08/25/2015] [Accepted: 08/25/2015] [Indexed: 12/16/2022]
Affiliation(s)
- Václav Kašička
- Institute of Organic Chemistry and Biochemistry, v.v.i; The Czech Academy of Sciences; Prague Czech Republic
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