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Huang Y, Shao X, Liu Y, Yan K, Ying W, He F, Wang D. RUPE-phospho: Rapid Ultrasound-Assisted Peptide-Identification-Enhanced Phosphoproteomics Workflow for Microscale Samples. Anal Chem 2023; 95:17974-17980. [PMID: 38011496 DOI: 10.1021/acs.analchem.3c02623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Global phosphoproteome profiling can provide insights into cellular signaling and disease pathogenesis. To achieve comprehensive phosphoproteomic analyses with minute quantities of material, we developed a rapid and sensitive phosphoproteomics sample preparation strategy based on ultrasound. We found that ultrasonication-assisted digestion can significantly improve peptide identification by 20% due to the generation of longer peptides that can be detected by mass spectrometry. By integrating this rapid ultrasound-assisted peptide-identification-enhanced proteomic method (RUPE) with streamlined phosphopeptide enrichment steps, we established RUPE-phospho, a fast and efficient strategy to characterize protein phosphorylation in mass-limited samples. This approach dramatically reduces the sample loss and processing time: 24 samples can be processed in 3 h; 5325 phosphosites, 4549 phosphopeptides, and 1888 phosphoproteins were quantified from 5 μg of human embryonic kidney (HEK) 293T cell lysate. In addition, 9219 phosphosites were quantified from 1-2 mg of OCT-embedded mouse brain with 120 min streamlined RUPE-phospho workflow. RUPE-phospho facilitates phosphoproteome profiling for microscale samples and will provide a powerful tool for proteomics-driven precision medicine research.
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Affiliation(s)
- Yuanxuan Huang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Science-Beijing (PHOENIX Center), Beijing Institute of Lifeomics, Beijing 102206, China
| | - Xianfeng Shao
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Science-Beijing (PHOENIX Center), Beijing Institute of Lifeomics, Beijing 102206, China
| | - Yuanyuan Liu
- The π-HuB Project Infrastructure, Guangzhou 510000, China
| | - Kehan Yan
- The π-HuB Project Infrastructure, Guangzhou 510000, China
| | - Wantao Ying
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Science-Beijing (PHOENIX Center), Beijing Institute of Lifeomics, Beijing 102206, China
| | - Fuchu He
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Science-Beijing (PHOENIX Center), Beijing Institute of Lifeomics, Beijing 102206, China
- The π-HuB Project Infrastructure, Guangzhou 510000, China
- Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Beijing 102206, China
| | - Dongxue Wang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Science-Beijing (PHOENIX Center), Beijing Institute of Lifeomics, Beijing 102206, China
- The π-HuB Project Infrastructure, Guangzhou 510000, China
- Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Beijing 102206, China
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Dridi C, Millette M, Aguilar B, Manus J, Salmieri S, Lacroix M. Effect of Physical and Enzymatic Pre-Treatment on the Nutritional and Functional Properties of Fermented Beverages Enriched with Cricket Proteins. Foods 2021; 10:2259. [PMID: 34681307 PMCID: PMC8534633 DOI: 10.3390/foods10102259] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/08/2021] [Accepted: 09/10/2021] [Indexed: 01/26/2023] Open
Abstract
The aim of this study was to evaluate the effects of γ-irradiation (IR), ultrasound (US), and combined treatments of ultrasound followed by γ-irradiation (US-IR), ultrasound followed by enzymatic hydrolysis with and without centrifugation (US-E and US-EWC, respectively), and ultrasound followed by γ-irradiation and enzymatic hydrolysis (US-IRE), on the digestibility and the nutritional value of fermented beverages containing probiotics. Results showed that US (20 min), IR (3 kGy) and US-IR (tUS = 20 min, dose = 3 kGy) treatments raised protein solubility from 11.5 to 21.5, 24.3 and 29.9%, respectively. According to our results, these treatments were accompanied by the increased amount of total sulfhydryl groups, surface hydrophobicity and changes to the secondary structure of the proteins measured by Fourier-transform infrared spectroscopy (FTIR). Fermented probiotic beverages, non-enriched (C) and enriched with untreated (Cr) or treated cricket protein with combined treatments were also evaluated for their in vitro protein digestibility. Results showed that the soluble fraction of US-IRE fermented beverage had the highest digestibility (94%) as compared to the whole fermented tested beverages. The peptides profile demonstrated that US-IRE had a low proportion of high molecular weight (MW) peptides (0.7%) and the highest proportion of low MW peptides by over 80% as compared to the other treatments.
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Affiliation(s)
- Chaima Dridi
- INRS Armand-Frappier Health Biotechnology Research Centre, Research Laboratories in Sciences, Applied to Food (RESALA), Canadian Irradiation Centre (CIC), Institute of Nutrition and Functional Foods (INAF), 531 Boulevard des Prairies, Laval, QC H7V 1B7, Canada; (C.D.); (J.M.); (S.S.)
| | - Mathieu Millette
- Bio-K Plus International Inc., a Kerry Company, Preclinical Research Division, 495 Armand-Frappier Blvd, Laval, QC H7V 4B3, Canada;
| | - Blanca Aguilar
- Research Laboratory of Industrial Microbiology, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, 1421, Blvd, Marcelino Garcia Barragan, Col. Olímpica, Guadalajara 44430, Jalisco, Mexico;
| | - Johanne Manus
- INRS Armand-Frappier Health Biotechnology Research Centre, Research Laboratories in Sciences, Applied to Food (RESALA), Canadian Irradiation Centre (CIC), Institute of Nutrition and Functional Foods (INAF), 531 Boulevard des Prairies, Laval, QC H7V 1B7, Canada; (C.D.); (J.M.); (S.S.)
| | - Stephane Salmieri
- INRS Armand-Frappier Health Biotechnology Research Centre, Research Laboratories in Sciences, Applied to Food (RESALA), Canadian Irradiation Centre (CIC), Institute of Nutrition and Functional Foods (INAF), 531 Boulevard des Prairies, Laval, QC H7V 1B7, Canada; (C.D.); (J.M.); (S.S.)
| | - Monique Lacroix
- INRS Armand-Frappier Health Biotechnology Research Centre, Research Laboratories in Sciences, Applied to Food (RESALA), Canadian Irradiation Centre (CIC), Institute of Nutrition and Functional Foods (INAF), 531 Boulevard des Prairies, Laval, QC H7V 1B7, Canada; (C.D.); (J.M.); (S.S.)
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Kim Y, Lee D, Kim J. Effects of incubation temperature and acetonitrile amount on microwave-assisted tryptic digestion of proteins. Anal Biochem 2019; 569:31-38. [PMID: 30707897 DOI: 10.1016/j.ab.2019.01.009] [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: 12/29/2018] [Revised: 01/23/2019] [Accepted: 01/25/2019] [Indexed: 11/29/2022]
Abstract
The effects of incubation temperature and acetonitrile (ACN) amount on microwave-assisted tryptic digestion of horse skeletal muscle myoglobin (MYG) and bovine serum albumin (BSA) were investigated. Microwave-assisted tryptic digestion was performed on BSA or MYG solutions containing different amounts (0, 10, and 20%) of ACN for different times (10, 20, 30, 40, and 50 min) at different temperatures (25, 37, and 55 °C). Conventional overnight tryptic digestion was also conducted with gentle mixing at 37 °C for 16 h. Digested samples were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. Similar sequence coverage (SC) values were obtained under most conditions except when the protein sample solutions were digested with 20% ACN at 55 °C, which provided the lowest SC for both MYG and BSA for all investigated digestion times. Considering the missed cleavage (MC) ratios for 50-min microwave-assisted digestion, the highest MC ratio, (i.e., lowest trypsin activity) was observed for the digestion condition of 20% ACN at 55 °C for both proteins, while the lowest MC ratio was observed with 0% ACN at 25 °C for MYG and with 0% ACN at 55 °C for BSA. Conventional overnight tryptic digestion at 37 °C provided more completely cleaved peptides than 50-min microwave-assisted tryptic digestion at the same temperature.
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Affiliation(s)
- Yeoseon Kim
- Department of Chemistry, Chungnam National University, Daejeon, Republic of Korea
| | - Dabin Lee
- Department of Chemistry, Chungnam National University, Daejeon, Republic of Korea
| | - Jeongkwon Kim
- Department of Chemistry, Chungnam National University, Daejeon, Republic of Korea.
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Perspectives on potentiating immunocapture-LC-MS for the bioanalysis of biotherapeutics and biomarkers. Bioanalysis 2018; 10:1679-1690. [PMID: 30371100 DOI: 10.4155/bio-2018-0205] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The integration of ligand-binding assay and LC-MS/MS (immunocapture-LC-MS) has unleashed the combined advantages of both powerful techniques for addressing the ever increasing bioanalytical challenges for biotherapeutics and biomarker assays. The highly specific, selective and sensitive characteristics of the immunocapture-LC-MS-based assays have enabled the determination of biotherapeutics and biomarkers in biomatrices with ease of method development, less requirements on key reagents as well as structural specificity for endogenous and engineered biomolecules. In addition, the versatile immunocapture-LC-MS technology has expanded into many challenging areas to enhance mechanistic studies of drug interactions with their targets. This paper intends to summarize our perspectives on enhancing the use of immunocapture-LC-MS in drug discovery and development for emerging new modalities.
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Wang D, Yan L, Ma X, Wang W, Zou M, Zhong J, Ding T, Ye X, Liu D. Ultrasound promotes enzymatic reactions by acting on different targets: Enzymes, substrates and enzymatic reaction systems. Int J Biol Macromol 2018; 119:453-461. [PMID: 30041035 DOI: 10.1016/j.ijbiomac.2018.07.133] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 12/24/2022]
Abstract
With the extensive application of enzyme-catalyzed reactions in numerous fields, improving enzymatic efficiency has attracted wide attention for reducing operating costs and increasing output. There are three targets throughout enzymatic reactions: the enzyme, substrate, and mixed reaction system. Ultrasound has been known to accelerate enzymatic reactions by acting on different targets. It can modify both enzyme and substrate macromolecules, which is helpful for enhancing enzyme activity and product yields. The synergistic effect of ultrasound and enzymes is widely reported to increase catalytic rates. The present review discusses the positive effect induced by ultrasound throughout the enzymatic process, including ultrasonic modification of enzymes, ultrasound assisted immobilization, ultrasonic pretreatment of substrates, and ultrasound assisted enzymatic reactions.
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Affiliation(s)
- Danli Wang
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
| | - Lufeng Yan
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Xiaobin Ma
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Wenjun Wang
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Mingming Zou
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Jianjun Zhong
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Tian Ding
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Hangzhou 310058, China; Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou 310058, China
| | - Xingqian Ye
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Hangzhou 310058, China; Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Donghong Liu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Hangzhou 310058, China; Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China.
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6
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Devi S, Wu BH, Chu PY, Liu YP, Wu HL, Ho YP. Studying the effect of microwave heating on the digestion process and identification of proteins. Electrophoresis 2016; 38:429-440. [PMID: 27770443 DOI: 10.1002/elps.201600392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/06/2016] [Accepted: 10/12/2016] [Indexed: 11/07/2022]
Abstract
The impact of microwave irradiation on the in-solution digestion processes and the detection limit of proteins are systematically studied. Kinetic processes of many peptides produced through the trypsin digestion of various proteins under microwave heating at 50°C were investigated with MALDI-MS. This study also examines the detection limits and digestion completeness of individual proteins under microwave heating at 50°C and at different time intervals (1, 5 and 30 min) using LC-MS. We conclude that if the peptides without missed cleavage dictate the detection limit, conventional digestion will lead to a better detection limit. The detection limit may not differ between the microwave and conventional heating if the peptides with missed cleavage sites and strong intensity are formed at the very early stage (i.e., less than 1 min) and are not further digested throughout the entire digestion process. The digestion of Escherichia coli lysate was compared under conventional and short time (microwave) conditions. The number of proteins identified under conventional heating exceeded that obtained from microwave heating over heating periods less than 5 min. The overall results show that the microwave-assisted digestion is not complete. Although the sequence coverage might be better, the detection limit might be worse than that under conventional heating.
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Affiliation(s)
- Shobha Devi
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Bo-Hung Wu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Pei-Yu Chu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Yue-Pei Liu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Hsin-Lin Wu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Yen-Peng Ho
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
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Ultrasound applications for the extraction, identification and delivery of food proteins and bioactive peptides. Trends Food Sci Technol 2015. [DOI: 10.1016/j.tifs.2015.07.012] [Citation(s) in RCA: 134] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Jiang S, Zhang Z, Li L. A one-step preparation method of monolithic enzyme reactor for highly efficient sample preparation coupled to mass spectrometry-based proteomics studies. J Chromatogr A 2015; 1412:75-81. [PMID: 26300481 DOI: 10.1016/j.chroma.2015.07.121] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 07/25/2015] [Accepted: 07/31/2015] [Indexed: 01/02/2023]
Abstract
Mass spectrometry (MS) coupled to sample preparation and separation techniques has become a primary tool for proteomics studies. However, due to sample complexity, it is often challenging to achieve fast and efficient sample preparation prior to MS analysis. In recent decades, monolithic materials have been developed not only as chromatographic media, but also as efficient solid supports for immobilizing multiple types of affinity reagents. Herein, the N-acryloxysuccinimide-co-acrylamide-co-N,N'-methylenebisacrylamide (NAS-AAm-Bis) monolith was fabricated within silanized 200 μm i.d. fused-silica capillaries and was used as an immobilized enzyme reactor (IMER). The column was conjugated with trypsin/Lys-C and Lys-N enzymes to allow enzymatic digestions to occur while protein mixture was loaded onto the IMER column followed by MS-based proteomics analysis. Similar MS signal and protein sequence coverage were observed using protein standard bovine serum albumin (BSA) compared to in-solution digestion. Furthermore, mouse serum, yeast, and human cell lysate samples were also subjected to enzymatic digestion by both IMER (in seconds to minutes) and conventional in solution digestion (overnight) for comparison in large-scale proteomics studies. Comparable protein identification results obtained by the two methods highlighted the potential of employing NAS-based IMER column for fast and highly efficient sample preparation for MS analysis in proteomics studies.
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Affiliation(s)
- Shan Jiang
- School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, United States
| | - Zichuan Zhang
- School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, United States
| | - Lingjun Li
- School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, United States; Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI 53706, United States.
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da Costa JP, Oliveira-Silva R, Daniel-da-Silva AL, Vitorino R. Bionanoconjugation for Proteomics applications — An overview. Biotechnol Adv 2014; 32:952-70. [DOI: 10.1016/j.biotechadv.2014.04.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 03/15/2014] [Accepted: 04/26/2014] [Indexed: 12/29/2022]
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10
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Islam MN, Zhang M, Adhikari B. The Inactivation of Enzymes by Ultrasound—A Review of Potential Mechanisms. FOOD REVIEWS INTERNATIONAL 2013. [DOI: 10.1080/87559129.2013.853772] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Optimization of separation and digestion conditions in immune complexome analysis. Anal Biochem 2013; 443:181-6. [DOI: 10.1016/j.ab.2013.08.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 08/21/2013] [Accepted: 08/26/2013] [Indexed: 11/18/2022]
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12
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Switzar L, Giera M, Niessen WMA. Protein Digestion: An Overview of the Available Techniques and Recent Developments. J Proteome Res 2013; 12:1067-77. [DOI: 10.1021/pr301201x] [Citation(s) in RCA: 164] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Linda Switzar
- AIMMS Division of BioMolecular
Analysis, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Martin Giera
- Division of Molecular Cell Physiology,
Faculty of Earth and Life Sciences, VU University Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
- Biomolecular Mass Spectrometry
Unit, Department of Parasitology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands
| | - Wilfried M. A. Niessen
- AIMMS Division of BioMolecular
Analysis, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
- hyphen MassSpec, de Wetstraat 8, 2332 XT Leiden, The Netherlands
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Yamaguchi H, Miyazaki M. Enzyme-immobilized reactors for rapid and efficient sample preparation in MS-based proteomic studies. Proteomics 2013; 13:457-66. [DOI: 10.1002/pmic.201200272] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 11/03/2012] [Accepted: 11/14/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Hiroshi Yamaguchi
- Liberal Arts Education Center; Tokai University; Minamiaso Kumamoto Japan
| | - Masaya Miyazaki
- Measurement Solution Research Center; National Institute of Advanced Industrial Science and Technology; Tosu Saga Japan
- Interdisciplinary Graduate School of Engineering Science; Kyushu University; Kasuga Fukuoka Japan
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Shin S, Yang HJ, Kim JH, Kim J, Lee JH, Park KH, Kim HS, Kim J. Clarification of a peak at m/z 1634 from tryptically digested cytochrome c. JOURNAL OF MASS SPECTROMETRY : JMS 2012; 47:1576-1581. [PMID: 23280746 DOI: 10.1002/jms.3119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 10/03/2012] [Accepted: 10/04/2012] [Indexed: 06/01/2023]
Abstract
A peptide peak at m/z 1634 in the mass spectrum of tryptically digested cytochrome c has been ambiguously assigned to either a peptide IFVQKCAQCHTVEK or a peptide CAQCHTVEK combined with a heme group (CAQCHTVEK + heme (Fe(III))). A comprehensive investigation was performed to clearly identify the origin of the peak. Tryptic digests of cytochrome c were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), liquid chromatography-tandem MS (LC-MS/MS), LC-ultraviolet (LC-UV), and MALDI Fourier transform-ion cyclotron resonance (FT-ICR) MS. The use of instruments with extremely high mass accuracy revealed the mass difference between the IFVQKCAQCHTVEK and the (CAQCHTVEK + heme (Fe(III))) ions. Fragmentation of the peptide associated with the unknown peak yielded a heme ion and other fragment ions originating from a (CAQCHTVEK + heme (Fe(III))) ion. Furthermore, an absorption peak at 395 nm confirmed the presence of a heme group in the unknown peptide. High mass accuracy analyses of MS and MS/MS spectra, in addition to three-dimensional UV contour mapping, showed that the peak at m/z 1634 is due to a (CAQCHTVEK + heme (Fe(III))) ion and not from protonated IFVQKCAQCHTVEK.
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Park SJ, Koo KM, Kim JH, Kim JK. Comparison of peptide guanidination efficiency using various reaction conditions. ANALYTICAL SCIENCE AND TECHNOLOGY 2012. [DOI: 10.5806/ast.2012.25.2.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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