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Mansuri MS, Bathla S, Lam TT, Nairn AC, Williams KR. Optimal conditions for carrying out trypsin digestions on complex proteomes: From bulk samples to single cells. J Proteomics 2024; 297:105109. [PMID: 38325732 PMCID: PMC10939724 DOI: 10.1016/j.jprot.2024.105109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/10/2024] [Accepted: 01/31/2024] [Indexed: 02/09/2024]
Abstract
To identify proteins by the bottom-up mass spectrometry workflow, enzymatic digestion is essential to break down proteins into smaller peptides amenable to both chromatographic separation and mass spectrometric analysis. Trypsin is the most extensively used protease due to its high cleavage specificity and generation of peptides with desirable positively charged N- and C-terminal amino acid residues that are amenable to reverse phase HPLC separation and MS/MS analyses. However, trypsin can yield variable digestion profiles and its protein cleavage activity is interdependent on trypsin source and quality, digestion time and temperature, pH, denaturant, trypsin and substrate concentrations, composition/complexity of the sample matrix, and other factors. There is therefore a need for a more standardized, general-purpose trypsin digestion protocol. Based on a review of the literature we delineate optimal conditions for carrying out trypsin digestions of complex proteomes from bulk samples to limiting amounts of protein extracts. Furthermore, we highlight recent developments and technological advances used in digestion protocols to quantify complex proteomes from single cells. SIGNIFICANCE: Currently, bottom-up MS-based proteomics is the method of choice for global proteome analysis. Since trypsin is the most utilized protease in bottom-up MS proteomics, delineating optimal conditions for carrying out trypsin digestions of complex proteomes in samples ranging from tissues to single cells should positively impact a broad range of biomedical research.
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Affiliation(s)
- M Shahid Mansuri
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA; Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06511, USA.
| | - Shveta Bathla
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511, USA
| | - TuKiet T Lam
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA; Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06511, USA; Keck MS & Proteomics Resource, Yale School of Medicine, New Haven, CT 06511, USA
| | - Angus C Nairn
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511, USA
| | - Kenneth R Williams
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA; Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06511, USA; Keck MS & Proteomics Resource, Yale School of Medicine, New Haven, CT 06511, USA.
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2
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The role of polymeric chains as a protective environment for improving the stability and efficiency of fluorogenic peptide substrates. Sci Rep 2022; 12:8818. [PMID: 35614307 PMCID: PMC9132916 DOI: 10.1038/s41598-022-12848-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 05/09/2022] [Indexed: 11/17/2022] Open
Abstract
We have faced the preparation of fully water-soluble fluorescent peptide substrate with long-term environmental stability (in solution more than 35 weeks) and, accordingly, with stable results in the use of this probe in determining the activity of enzymes. We have achieved this goal by preparing a co-polymer of the commercial N-vinyl-2-pyrrolidone (99.5% mol) and a fluorescent substrate for trypsin activity determination having a vinylic group (0.5%). The activity of trypsin has been measured in water solutions of this polymer over time, contrasted against the activity of both the commercial substrate Z-L-Arg-7-amido-4-methylcoumarin hydrochloride and its monomeric derivative, prepared ad-hoc. Initially, the activity of the sensory polymer was 74.53 ± 1.72 nmol/min/mg of enzyme, while that of the commercial substrate was 20.44 ± 0.65 nmol/min/mg of enzyme, the former maintained stable along weeks and the latter with a deep decay to zero in three weeks. The ‘protection’ effect exerted by the polymer chain has been studied by solvation studies by UV–Vis spectroscopy, steady-state & time resolved fluorescence, thermogravimetry and isothermal titration calorimetry.
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3
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Le Feunteun S, Verkempinck S, Floury J, Janssen A, Kondjoyan A, Marze S, Mirade PS, Pluschke A, Sicard J, van Aken G, Grauwet T. Mathematical modelling of food hydrolysis during in vitro digestion: From single nutrient to complex foods in static and dynamic conditions. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.08.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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4
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Rivera Del Rio A, Keppler JK, Boom RM, Janssen AEM. Protein acidification and hydrolysis by pepsin ensure efficient trypsin-catalyzed hydrolysis. Food Funct 2021; 12:4570-4581. [PMID: 33908536 DOI: 10.1039/d1fo00413a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Enzyme-catalysed hydrolysis is important in protein digestion. Protein hydrolysis is initiated by pepsin at low pH in the stomach. However, pepsin action and acidification happen simultaneously to gastric emptying, especially for liquid meals. Therefore, different extents of exposure to the gastric environment change the composition of the chyme that is emptied from the stomach into the small intestine over time. We assessed the susceptibility of a protein to trypsin-catalysed hydrolysis in the small intestine, depending on its pH and hydrolysis history, simulating chyme at different times after the onset of gastric emptying. Isothermal titration calorimetry was used to study the kinetics of pepsin and trypsin-catalysed hydrolysis. Bovine serum albumin (BSA) that was acidified and hydrolysed with pepsin, showed the highest extent and most efficient hydrolysis by trypsin. BSA in the chyme that would be first emptied from the stomach, virtually bypassing gastric acidity and peptic action, reduced trypsin-catalysed hydrolysis by up to 58% compared to the acidified, intact protein, and 77% less than the acidified, pepsin-hydrolysate. The least efficient substrate for trypsin-catalysed hydrolysis was the acidified, intact protein with a specificity constant (kcat/Km) nearly five times lower than that of the acidified, pepsin-hydrolysate. Our results illustrate the synergy between pepsin and trypsin hydrolysis, and indicate that gastric hydrolysis increases the efficiency of the subsequent trypsin-catalysed hydrolysis of a model protein in the small intestine.
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Affiliation(s)
- Andrea Rivera Del Rio
- Food Process Engineering, Wageningen University, P.O. Box 176700 AA, Wageningen, The Netherlands.
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5
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Wang Y, Wang G, Moitessier N, Mittermaier AK. Enzyme Kinetics by Isothermal Titration Calorimetry: Allostery, Inhibition, and Dynamics. Front Mol Biosci 2020; 7:583826. [PMID: 33195429 PMCID: PMC7604385 DOI: 10.3389/fmolb.2020.583826] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/11/2020] [Indexed: 12/14/2022] Open
Abstract
Isothermal titration calorimetry (ITC) involves accurately measuring the heat that is released or absorbed in real time when one solution is titrated into another. This technique is usually used to measure the thermodynamics of binding reactions. However, there is mounting interest in using it to measure reaction kinetics, particularly enzymatic catalysis. This application of ITC has been steadily growing for the past two decades, and the method is proving to be sensitive, generally applicable, and capable of providing information on enzyme activity that is difficult to obtain using traditional biochemical assays. This review aims to give a broad overview of the use of ITC to measure enzyme kinetics. It describes several different classes of ITC experiment, their strengths and weaknesses, and recent methodological advancements. A summary of applications in the literature is given and several examples where ITC has been used to investigate challenging aspects of enzyme behavior are presented in more detail. These include examples of allostery, where small-molecule binding outside the active site modulates activity. We describe the use of ITC to measure the strength, mode (i.e., competitive, uncompetitive, or mixed), and association and dissociation kinetics of enzyme inhibitors. Further, we provide examples of ITC applied to complex, heterogeneous mixtures, such as insoluble substrates and live cells. These studies exemplify the wide range of problems where ITC can provide answers, and illustrate the versatility of the technique and potential for future development and applications.
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Affiliation(s)
- Yun Wang
- Department of Chemistry, McGill University, Montreal, QC, Canada
| | - Guanyu Wang
- Department of Chemistry, McGill University, Montreal, QC, Canada
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6
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Phytase catalysis of dephosphorylation studied using isothermal titration calorimetry and electrospray ionization time-of-flight mass spectroscopy. Anal Biochem 2020; 606:113859. [DOI: 10.1016/j.ab.2020.113859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 11/21/2022]
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7
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Melikishvili S, Dizon M, Hianik T. Application of high-resolution ultrasonic spectroscopy for real-time monitoring of trypsin activity in β-casein solution. Food Chem 2020; 337:127759. [PMID: 32777568 DOI: 10.1016/j.foodchem.2020.127759] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 07/30/2020] [Accepted: 08/02/2020] [Indexed: 11/29/2022]
Abstract
High-resolution ultrasonic spectroscopy (HR-US) was applied for real-time monitoring of β-casein hydrolysis by trypsin at various conditions for the first time. The technique is based on the precision measurement of hydration changes proportional to the number of peptide bond hydrolyzed. As HR-US exhibits ultrasonic transparency for most solution, the analysis did not require optical transparency like for 2,4,6-trinitrobenzenesulfonic acid (TNBS) assay. Appropriate enzymatic models were fitted with degree of hydrolysis (dh) profiles to provide kinetic and mechanistic description of proteolysis in terms of initial hydrolysis rate, r0, and rate constant of hydrolysis, kh, and enzyme inactivation, kd. Maximal r0 and dh were obtained at 45 °C and pH 8. The exponential dependence of kinetic parameters allowed determination of the activation (EA = 50.3 ± 7 kJ/mol) and deactivation (ED = 62.23 ± 3 kJ/mol) energies of hydrolysis. The ultrasonic assay provided rapid detection of trypsin activity even at sub-nanomolar concentration.
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Affiliation(s)
- Sopio Melikishvili
- Department of Nuclear Physics and Biophysics, Comenius University, Mlynska dolina F1, 842 48 Bratislava, Slovakia
| | - Mark Dizon
- School of Chemistry and Chemical Biology, University College of Dublin, Belfield, Dublin 4, Ireland
| | - Tibor Hianik
- Department of Nuclear Physics and Biophysics, Comenius University, Mlynska dolina F1, 842 48 Bratislava, Slovakia.
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8
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Dong L, Lv M, Gao X, Zhang L, Rogers M, Cao Y, Lan Y. In vitrogastrointestinal digestibility of phytosterol oleogels: influence of self-assembled microstructures on emulsification efficiency and lipase activity. Food Funct 2020; 11:9503-9513. [DOI: 10.1039/d0fo01642j] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The objective of this study was to investigate the influence of a self-assembled microstructure on lipid digestibility of phytosterol (γ-oryzanol and β-sitosterol) oleogels, including the oil emulsification process and further lipolysis.
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Affiliation(s)
- Lulu Dong
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods
- College of Food Sciences
- South China Agricultural University
- Guangzhou
- P.R. China
| | - Muwen Lv
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods
- College of Food Sciences
- South China Agricultural University
- Guangzhou
- P.R. China
| | - Xiangyang Gao
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods
- College of Food Sciences
- South China Agricultural University
- Guangzhou
- P.R. China
| | - Luping Zhang
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods
- College of Food Sciences
- South China Agricultural University
- Guangzhou
- P.R. China
| | - Michael Rogers
- Department of Food Science
- University of Guelph
- Guelph
- Canada
| | - Yong Cao
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods
- College of Food Sciences
- South China Agricultural University
- Guangzhou
- P.R. China
| | - Yaqi Lan
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods
- College of Food Sciences
- South China Agricultural University
- Guangzhou
- P.R. China
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9
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Maximova K, Reuter N, Trylska J. Peptidomimetic inhibitors targeting the membrane-binding site of the neutrophil proteinase 3. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:1502-1509. [DOI: 10.1016/j.bbamem.2019.06.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/04/2019] [Accepted: 06/17/2019] [Indexed: 02/07/2023]
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10
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Santra M, Luthra-Guptasarma M. Assaying Collagenase Activity by Specific Labeling of Freshly Generated N-Termini with Fluorescamine at Mildly Acidic pH. Int J Pept Res Ther 2019. [DOI: 10.1007/s10989-019-09885-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Szabó K, Kandra L, Gyémánt G. Studies on the reversible enzyme reaction of rabbit muscle glycogen phosphorylase b using isothermal titration calorimetry. Carbohydr Res 2019; 477:58-65. [PMID: 31005807 DOI: 10.1016/j.carres.2019.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/27/2019] [Accepted: 03/30/2019] [Indexed: 10/27/2022]
Abstract
Glycogen phosphorylase enzymes (GP) catalyse reversible reactions; the glucose transfer from glycogen to inorganic phosphate (Pi, phosphorolysis) or the reverse glucose transfer from glucose-1-phosphate (G-1-P) to glycogen (synthesis). Rabbit muscle GPb (rmGPb) was used as a model enzyme to study the reversible enzyme reaction. To follow both directions of this reversible reaction, we have developed a novel isothermal titration calorimetry (ITC) method for the determination of the direct reaction rate. The preference of forward or reverse reaction was ensured by the 0.1 or 10 concentration ratios of G-1-P/Pi, respectively. Substrate specificity was studied using different maltooligosaccharides and glycogen. Based on the KM values, glycogen and 2-chloro-4-nitrophenyl maltoheptaoside (CNP-G7) were found to be analogous substrates, which allowed to optimize the method by taking advantage of the CNP chromophore being detectable in HPLC. In case of CNP-G7, substrate inhibition was observed and characterised by Ki of 23 ± 7 mM. Inhibition of human GP is a promising strategy for the treatment of diabetes. Our ITC measurements have confirmed that caffeine and glucopyranosylidene-spiro-thiohydantoin (GTH), as known GPb inhibitors, inhibit the rmGPb-catalysed reversible reaction in both directions. Ki values obtained in the direction of synthesis (1.92 ± 0.14 mM for caffeine and 11.5 ± 2.0 μM for GTH) have been shown to be in good agreement with the Ki values obtained in the direction of phosphorolysis (4.05 ± 0.26 mM for caffeine and 13.8 ± 1.6 μM for GTH). The higher difference between the inhibition constants of caffeine was explained by the non-competitive mechanism. The described ITC method using the developed experimental design and reaction conditions is suitable for activity measurements of different phosphorylase enzymes on various substrates and is applicable for inhibition studies as well.
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Affiliation(s)
- Kármen Szabó
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Lili Kandra
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Gyöngyi Gyémánt
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary.
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12
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Maximova K, Wojtczak J, Trylska J. Enzyme kinetics in crowded solutions from isothermal titration calorimetry. Anal Biochem 2018; 567:96-105. [PMID: 30439369 DOI: 10.1016/j.ab.2018.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/08/2018] [Accepted: 11/05/2018] [Indexed: 11/30/2022]
Abstract
Isothermal titration calorimetry (ITC) is a universal technique that directly measures the heat absorbed or released in a process. ITC is typically used to determine thermodynamic parameters of association of molecules without the need to label them. However, ITC is still rarely applied to study chemical reactions catalyzed by enzymes. In addition, these few studies of enzyme kinetic measurements that have been performed were in diluted solutions. Yet, to estimate realistic kinetic parameters, we have to account for the fact that enzymatic reactions in cells occur in a crowded environment because cells contain 200-400 g/L of macromolecular crowders such as proteins, ribosomes and lipids. Thus we expanded the ITC application for solutions mimicking the cellular environment by adding various macromolecular crowders. We investigated how these crowders affect the kinetics of trypsin-catalyzed reactions and determined the Michaelis-Menten parameters for hydrolysis of two trypsin substrates: Nα-benzoyl-l-arginine ethyl ester (BAEE) and Nα-benzoyl-dl-arginine β-naphthylamide (BANA). Since ITC enables investigations of complex and turbid solutions with label-free reagents, it seems a perfect technique for kinetic analyses in crowded solutions. ITC also offers the opportunity to control enzyme-crowder and substrate-crowder interactions.
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Affiliation(s)
- Ksenia Maximova
- Centre of New Technologies University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland.
| | - Jakub Wojtczak
- Centre of New Technologies University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland; Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland
| | - Joanna Trylska
- Centre of New Technologies University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland.
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13
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Salaga M, Binienda A, Draczkowski P, Kosson P, Kordek R, Jozwiak K, Fichna J. Novel peptide inhibitor of dipeptidyl peptidase IV (Tyr-Pro-D-Ala-NH 2) with anti-inflammatory activity in the mouse models of colitis. Peptides 2018; 108:34-45. [PMID: 30179653 DOI: 10.1016/j.peptides.2018.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 08/03/2018] [Accepted: 08/24/2018] [Indexed: 12/19/2022]
Abstract
Protease inhibition has become a new possible approach in the inflammatory bowel disease (IBD) therapy. A serine exopeptidase, dipeptidyl peptidase IV (DPP IV) is responsible for inactivation of incretin hormone, glucagon-like peptide 2 (GLP-2), a potent stimulator of intestinal epithelium regeneration and growth. Recently we showed that the novel peptide analog of endomorphin-2, EMDB-1 (Tyr-Pro-D-ClPhe-Phe-NH2) is a potent blocker of DPP IV and exhibits an anti-inflammatory activity in vivo. The aim of this study was to design, synthesize and characterize the therapeutic activity and mechanism of action of a series of novel EMDB-1 analogs. The inhibitory potential of all peptides was evaluated using the fluorometric screening assay employing Gly-Pro-Aminomethylcoumarin (AMC) to measure DPP IV activity. Consequently, one compound, namely DI-1 was selected and its therapeutic activity evaluated using mouse models of experimental colitis (induced by TNBS and DSS). Macro- and microscopic score, ulcer score, colonic wall thickness as well as myeloperoxidase activity were measured. We showed that DI-1 blocks DPP IV in vitro (IC50 = 0.76 ± 0.04 nM) and attenuates acute, semichronic and relapsing TNBS- as well as DSS-induced colitis in mice after topical administration. Its anti-inflammatory action is associated with the increase of colonic GLP-2 but not GLP2 receptor or DPP IV expression. Our results validate DPP IV as a pharmacological target for the anti-IBD drugs and its inhibitors, such as DI-1, have the potential to become valuable anti-inflammatory therapeutics.
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Affiliation(s)
- M Salaga
- Department of Biochemistry, Department of Pathology, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - A Binienda
- Department of Biochemistry, Department of Pathology, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - P Draczkowski
- Department of Biopharmacy, Medical University of Lublin, Poland
| | - P Kosson
- Mossakowski Medical Research Centre Polish Academy of Sciences, Warsaw, Poland
| | - R Kordek
- Department of Biochemistry, Department of Pathology, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - K Jozwiak
- Department of Biopharmacy, Medical University of Lublin, Poland
| | - J Fichna
- Department of Biochemistry, Department of Pathology, Faculty of Medicine, Medical University of Lodz, Lodz, Poland.
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14
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Maximova K, Venken T, Reuter N, Trylska J. d-Peptides as inhibitors of PR3-membrane interactions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:458-466. [PMID: 29132840 DOI: 10.1016/j.bbamem.2017.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 11/02/2017] [Accepted: 11/07/2017] [Indexed: 01/08/2023]
Abstract
Proteinase 3 (PR3) is a neutrophil serine protease present in cytoplasmic granules but also expressed at the neutrophil surface where it mediates proinflammatory effects. Studies of the underlying molecular mechanisms have been hampered by the lack of inhibitors of the PR3 membrane anchorage. Indeed while there exist inhibitors of the catalytic activity of PR3, its membrane interfacial binding site (IBS) is distinct from its catalytic site. The IBS has been characterized both by mutagenesis experiments and molecular modeling. Through docking and molecular dynamics simulations we have designed d-peptides targeting the PR3 IBS. We used surface plasmon resonance to evaluate their effect on the binding of PR3 to phospholipid bilayers. Next, we verified their ability of binding to PR3 via fluorescence spectroscopy and isothermal titration calorimetry. The designed peptides did not affect the catalytic activity of PR3. A few peptides bound to PR3 hydrophobic pockets and inhibited PR3 binding to lipids. While the (KFF)3K d-peptide inconveniently showed a significant affinity for the lipids, another d-peptide (SAKEAFFKLLAS) did not and it inhibited the PR3-membrane binding site with IC50 of about 40μM. Our work puts forward d-peptides as promising inhibitors of peripheral protein-membrane interactions, which remain high-hanging fruits in drug design.
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Affiliation(s)
- Ksenia Maximova
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Tom Venken
- Department of Molecular Biology, University of Bergen, 5008 Bergen, Norway; Flemish Institute for Technological Research, VITO, B-2400 Mol, Belgium
| | - Nathalie Reuter
- Department of Molecular Biology, University of Bergen, 5008 Bergen, Norway.
| | - Joanna Trylska
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland.
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15
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Falconer RJ. Applications of isothermal titration calorimetry - the research and technical developments from 2011 to 2015. J Mol Recognit 2016; 29:504-15. [PMID: 27221459 DOI: 10.1002/jmr.2550] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 04/05/2016] [Accepted: 04/14/2016] [Indexed: 12/12/2022]
Abstract
Isothermal titration calorimetry is a widely used biophysical technique for studying the formation or dissociation of molecular complexes. Over the last 5 years, much work has been published on the interpretation of isothermal titration calorimetry (ITC) data for single binding and multiple binding sites. As over 80% of ITC papers are on macromolecules of biological origin, this interpretation is challenging. Some researchers have attempted to link the thermodynamics constants to events at the molecular level. This review highlights work carried out using binding sites characterized using x-ray crystallography techniques that allow speculation about individual bond formation and the displacement of individual water molecules during ligand binding and link these events to the thermodynamic constants for binding. The review also considers research conducted with synthetic binding partners where specific binding events like anion-π and π-π interactions were studied. The revival of assays that enable both thermodynamic and kinetic information to be collected from ITC data is highlighted. Lastly, published criticism of ITC research from a physical chemistry perspective is appraised and practical advice provided for researchers unfamiliar with thermodynamics and its interpretation. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Robert J Falconer
- Department of Chemical and Biological Engineering, ChELSI Institute, University of Sheffield, Sheffield, S1 3JD, UK.
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16
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Lehoczki G, Szabó K, Takács I, Kandra L, Gyémánt G. Simple ITC method for activity and inhibition studies on human salivary α-amylase. J Enzyme Inhib Med Chem 2016; 31:1648-53. [DOI: 10.3109/14756366.2016.1161619] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Gábor Lehoczki
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Kármen Szabó
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - István Takács
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Lili Kandra
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Gyöngyi Gyémánt
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
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17
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Rana H, Moussatche P, Rocha LS, Abdellaoui S, Minteer SD, Moomaw EW. Isothermal titration calorimetry uncovers substrate promiscuity of bicupin oxalate oxidase from Ceriporiopsis subvermispora. Biochem Biophys Rep 2016; 5:396-400. [PMID: 28955847 PMCID: PMC5600335 DOI: 10.1016/j.bbrep.2016.01.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 12/30/2015] [Accepted: 01/28/2016] [Indexed: 12/05/2022] Open
Abstract
Isothermal titration calorimetry (ITC) may be used to determine the kinetic parameters of enzyme-catalyzed reactions when neither products nor reactants are spectrophotometrically visible and when the reaction products are unknown. We report here the use of the multiple injection method of ITC to characterize the catalytic properties of oxalate oxidase (OxOx) from Ceriporiopsis subvermispora (CsOxOx), a manganese dependent enzyme that catalyzes the oxygen-dependent oxidation of oxalate to carbon dioxide in a reaction coupled with the formation of hydrogen peroxide. CsOxOx is the first bicupin enzyme identified that catalyzes this reaction. The multiple injection ITC method of measuring OxOx activity involves continuous, real-time detection of the amount of heat generated (dQ) during catalysis, which is equal to the number of moles of product produced times the enthalpy of the reaction (ΔHapp). Steady-state kinetic constants using oxalate as the substrate determined by multiple injection ITC are comparable to those obtained by a continuous spectrophotometric assay in which H2O2 production is coupled to the horseradish peroxidase-catalyzed oxidation of 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and by membrane inlet mass spectrometry. Additionally, we used multiple injection ITC to identify mesoxalate as a substrate for the CsOxOx-catalyzed reaction, with a kinetic parameters comparable to that of oxalate, and to identify a number of small molecule carboxylic acid compounds that also serve as substrates for the enzyme. ITC is used to assay the catalytic activity of oxalate oxidase. ITC enzymatic assay is sensitive, direct, and continuous. Mesoxalate and other carboxylic acids are substrates for oxalate oxidase.
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Affiliation(s)
- Hassan Rana
- Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA 30144, USA
| | | | - Lis Souza Rocha
- Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA 30144, USA
| | - Sofiene Abdellaoui
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Shelley D Minteer
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Ellen W Moomaw
- Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA 30144, USA
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Application of ITC in foods: A powerful tool for understanding the gastrointestinal fate of lipophilic compounds. Biochim Biophys Acta Gen Subj 2015; 1860:1026-1035. [PMID: 26456046 DOI: 10.1016/j.bbagen.2015.10.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 09/22/2015] [Accepted: 10/01/2015] [Indexed: 01/08/2023]
Abstract
BACKGROUND Isothermal titration calorimetry (ITC) is a biophysical technique widely used to study molecular interactions in biological and non-biological systems. It can provide important information about molecular interactions (such as binding constant, number of binding sites, free energy, enthalpy, and entropy) simply by measuring the heat absorbed or released during an interaction between two liquid solutions. SCOPE OF THE REVIEW In this review, we present an overview of ITC applications in food science, with particular focus on understanding the fate of lipids within the human gastrointestinal tract. In this area, ITC can be used to study micellization of bile salts, inclusion complex formation, the interaction of surface-active molecules with proteins, carbohydrates and lipids, and the interactions of lipid droplets. MAJOR CONCLUSIONS ITC is an extremely powerful tool for measuring molecular interactions in food systems, and can provide valuable information about many types of interactions involving food components such as proteins, carbohydrates, lipids, surfactants, and minerals. For systems at equilibrium, ITC can provide fundamental thermodynamic parameters that can be used to establish the physiochemical origin of molecular interactions. GENERAL SIGNIFICANCE It is expected that ITC will continue to be utilized as a means of providing fundamental information about complex materials such as those found in foods. This knowledge may be used to create functional foods designed to behave in the gastrointestinal tract in a manner that will improve human health and well-being.
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Improving the activity of the subtilisin nattokinase by site-directed mutagenesis and molecular dynamics simulation. Biochem Biophys Res Commun 2015; 465:580-6. [DOI: 10.1016/j.bbrc.2015.08.063] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 08/14/2015] [Indexed: 11/17/2022]
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