1
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Uversky VN, Kulkarni P. Intrinsically disordered proteins: Chronology of a discovery. Biophys Chem 2021; 279:106694. [PMID: 34607199 DOI: 10.1016/j.bpc.2021.106694] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/15/2021] [Accepted: 09/23/2021] [Indexed: 10/20/2022]
Abstract
Intrinsic disorder is a new reality that appears to penetrate every corner of modern protein science. It is difficult to imagine that only 20 years ago the situation was completely different, and almost nobody had heard about 'structure-less' but functional proteins. As a matter of fact, for many at that time, this idea was completely heretical when viewed in light of the then dominating lock-and-key model describing the protein structure-function relationship, where a unique amino acid sequence defines a unique crystal-like 3D structure that serves as a prerequisite for a unique function of a protein. It seems like the entire field of protein intrinsic disorder has magically emerged at the turn of the century due to a revelation to a small group of researchers. Although this may very well be true, literature shows that the first observations contradicting the lock-and-key view of protein functionality started to appear almost immediately after this model was proposed. The goal of this article is to provide a brief chronology (though admittedly a subjective one) of the events in the field of protein science that eventually culminated in the discovery of the protein intrinsic disorder phenomenon. The entire process represents a good example of the "dwarf standing on the shoulders of giants" (Latin: nanos gigantum humeris insidentes) metaphor, where the truth is discovered by building on previous discoveries.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy pereulok, 9, Dolgoprudny, 141700 Moscow region, Russia.
| | - Prakash Kulkarni
- Department of Medical Oncology, City of Hope National Medical Center, 1500 Duarte Rd, Duarte, CA, United States
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2
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Bernard H, Hazebrouck S, Gaiani N, Adel-Patient K. Allergen Risk Assessment for Specific Allergy to Small Ruminant's Milk: Development of Sensitive Immunoassays to Detect Goat's and Sheep's Milk Contaminations in Dairy Food Matrices. FRONTIERS IN ALLERGY 2021; 2:733875. [PMID: 35386964 PMCID: PMC8974779 DOI: 10.3389/falgy.2021.733875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/07/2021] [Indexed: 12/02/2022] Open
Abstract
Despite a high level of sequence identity between cow's, goat's, and sheep's milk (CM, GM, and SM, respectively) proteins, some patients tolerant to CM are allergic to GM and SM. In most cases, this specificity is due to the presence of IgE antibodies that bind only to caprine and ovine caseins. The patients may then develop severe allergic reactions after ingestion of CM products contaminated with low amounts of GM or SM. We thus aimed to develop an assay able to detect traces of caprine/ovine β-caseins in different food matrices, irrespective of the presence of the bovine homolog. We produced monoclonal antibodies (mAbs) specific to caprine caseins in mice tolerized to the bovine whole casein then sensitized to the caprine whole casein. In order to develop a two-site immunometric assay, we selected mAbs that could discriminate the caprine β-casein from its bovine homolog. Characteristics and performances of two tests were determined with various dairy products. Results were analyzed in relation with the IgE-immunoreactivity of the food matrices, thanks to sera from CM, GM/SM allergic patients. Our two-site immunometric assays demonstrated a high sensitivity with a detection limit of 1.6–3.2 ng/mL of caprine and ovine β-caseins. The tests were able to detect contaminations of GM in CM at the ppm level. Heat-treatment, ripening and coagulation processes, usually applied to dairy products that exhibit a very high IgE-immunoreactivity, did not impair the test sensitivity. These quantitative assays could then be useful for the risk assessment of food products potentially contaminated with GM and SM in order to prevent adverse reactions in patients specifically allergic to these milks.
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Markoska T, Vasiljevic T, Huppertz T. Unravelling Conformational Aspects of Milk Protein Structure-Contributions from Nuclear Magnetic Resonance Studies. Foods 2020; 9:E1128. [PMID: 32824355 PMCID: PMC7466366 DOI: 10.3390/foods9081128] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 11/30/2022] Open
Abstract
Changes in the molecular structure and association of milk proteins lead to many desirable (under controlled conditions) or undesirable characteristics of dairy products. Several methods have been used to study the structure of milk proteins and changes therein in different environments. Whey proteins are an excellent model for secondary structure studies using circular dichroism (CD), Fourier-transform infrared spectroscopy (FTIR) and tertiary structure studies using X-ray crystallography and nuclear magnetic resonance (NMR). However, caseins, the most abundant protein class in milk, are far more difficult to characterize. The tertiary structure of caseins cannot be observed by X-ray crystallography due to the inability to crystallize caseins. However, NMR is an appropriate approach for structural elucidation. Thus far, NMR was applied on specific peptides of individual caseins of the molecules including phosphoserine centers and colloidal calcium phosphate. The literature focuses on these parts of the molecule due to its importance in building the sub-unit particles involving individual caseins and calcium phosphate nanoclusters. This review focuses on present structural studies of milk proteins using NMR and their importance in dairy processing.
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Affiliation(s)
- Tatijana Markoska
- Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities, College of Health and Biomedicine, Victoria University, Melbourne VIC 8001, Australia; (T.M.); (T.V.)
| | - Todor Vasiljevic
- Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities, College of Health and Biomedicine, Victoria University, Melbourne VIC 8001, Australia; (T.M.); (T.V.)
| | - Thom Huppertz
- Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities, College of Health and Biomedicine, Victoria University, Melbourne VIC 8001, Australia; (T.M.); (T.V.)
- FrieslandCampina, 3818 LE Amersfoort, The Netherlands
- Food Quality and Design Group, Wageningen University and Research, 6808 WG Wageningen, The Netherlands
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McNelles SA, Marando VM, Adronov A. Globular Polymer Grafts Require a Critical Size for Efficient Molecular Sieving of Enzyme Substrates. Angew Chem Int Ed Engl 2019; 58:8448-8453. [PMID: 30893493 DOI: 10.1002/anie.201902864] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Stuart A. McNelles
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - Victoria M. Marando
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - Alex Adronov
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
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5
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McNelles SA, Marando VM, Adronov A. Globular Polymer Grafts Require a Critical Size for Efficient Molecular Sieving of Enzyme Substrates. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Stuart A. McNelles
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - Victoria M. Marando
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - Alex Adronov
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
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6
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Vincent M, Uversky VN, Schnell S. On the Need to Develop Guidelines for Characterizing and Reporting Intrinsic Disorder in Proteins. Proteomics 2019; 19:e1800415. [PMID: 30793871 DOI: 10.1002/pmic.201800415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/05/2019] [Indexed: 01/02/2023]
Abstract
Since the early 2000s, numerous computational tools have been created and used to predict intrinsic disorder in proteins. At present, the output from these algorithms is difficult to interpret in the absence of standards or references for comparison. There are many reasons to establish a set of standard-based guidelines to evaluate computational protein disorder predictions. This viewpoint explores a handful of these reasons, including standardizing nomenclature to improve communication, rigor and reproducibility, and making it easier for newcomers to enter the field. An approach for reporting predicted disorder in single proteins with respect to whole proteomes is discussed. The suggestions are not intended to be formulaic; they should be viewed as a starting point to establish guidelines for interpreting and reporting computational protein disorder predictions.
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Affiliation(s)
- Michael Vincent
- Interdisciplinary Biological Sciences, Northwestern University, Evanston, IL, 60208, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, 142290, Moscow, Russia
| | - Santiago Schnell
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, 48109, USA
- Department of Computational Medicine & Bioinformatics, University of Michigan Medical School, Michigan, 48109, USA
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7
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Melnikova DL, Skirda VD, Nesmelova IV. Effect of Intrinsic Disorder and Self-Association on the Translational Diffusion of Proteins: The Case of α-Casein. J Phys Chem B 2017; 121:2980-2988. [PMID: 28346777 DOI: 10.1021/acs.jpcb.7b00772] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Translational diffusion is the major mode of macromolecular transport in leaving organisms, and therefore it is vital to many biological and biotechnological processes. Although translational diffusion of proteins has received considerable theoretical and experimental scrutiny, much of that attention has been directed toward the description of globular proteins. The translational diffusion of intrinsically disordered proteins (IDPs), however, is much less studied. Here, we use a pulsed-gradient nuclear magnetic resonance technique (PFG NMR) to investigate the translational diffusion of a disordered protein in a wide range of concentrations using α-casein that belongs to the class of natively disordered proteins as an example.
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Affiliation(s)
- Daria L Melnikova
- Department of Physics, Kazan Federal University , Kazan 420011, Russia
| | - Vladimir D Skirda
- Department of Physics, Kazan Federal University , Kazan 420011, Russia
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8
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Carbonaro M, Maselli P, Nucara A. Structural aspects of legume proteins and nutraceutical properties. Food Res Int 2015. [DOI: 10.1016/j.foodres.2014.11.007] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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9
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Naqvi MA, Rauscher S, Pomès R, Rousseau D. The Conformational Ensemble of the β-Casein Phosphopeptide Reveals Two Independent Intrinsically Disordered Segments. Biochemistry 2014; 53:6402-8. [DOI: 10.1021/bi500107u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Muhammad Ali Naqvi
- Department
of Chemistry and Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
| | - Sarah Rauscher
- Max Plank Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Régis Pomès
- Department
of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
- Molecular
Structure and Function, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Dérick Rousseau
- Department
of Chemistry and Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
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10
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Wang X, Guo H, Zhang W, Wen P, Zhang H, Guo Z, Ren F. Effect of iron saturation level of lactoferrin on osteogenic activity in vitro and in vivo. J Dairy Sci 2013; 96:33-9. [DOI: 10.3168/jds.2012-5692] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 10/06/2012] [Indexed: 01/01/2023]
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11
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Kolb AF, Huber RC, Lillico SG, Carlisle A, Robinson CJ, Neil C, Petrie L, Sorensen DB, Olsson IAS, Whitelaw CBA. Milk lacking α-casein leads to permanent reduction in body size in mice. PLoS One 2011; 6:e21775. [PMID: 21789179 PMCID: PMC3138747 DOI: 10.1371/journal.pone.0021775] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Accepted: 06/11/2011] [Indexed: 01/01/2023] Open
Abstract
The major physiological function of milk is the transport of amino acids, carbohydrates, lipids and minerals to mammalian offspring. Caseins, the major milk proteins, are secreted in the form of a micelle consisting of protein and calcium-phosphate. We have analysed the role of the milk protein α-casein by inactivating the corresponding gene in mice. Absence of α-casein protein significantly curtails secretion of other milk proteins and calcium-phosphate, suggesting a role for α-casein in the establishment of casein micelles. In contrast, secretion of albumin, which is not synthesized in the mammary epithelium, into milk is not reduced. The absence of α-casein also significantly inhibits transcription of the other casein genes. α-Casein deficiency severely delays pup growth during lactation and results in a life-long body size reduction compared to control animals, but has only transient effects on physical and behavioural development of the pups. The data support a critical role for α-casein in casein micelle assembly. The results also confirm lactation as a critical window of metabolic programming and suggest milk protein concentration as a decisive factor in determining adult body weight.
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Affiliation(s)
- Andreas F Kolb
- Molecular Recognition Group, Hannah Research Institute, Ayr, United Kingdom.
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12
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Kamilya T, Pal P, Mahato M, Sarkar R, Talapatra GB. Incorporation of pepsin within zwitterionic, anionic, and cationic lipid monolayers: A comparative study. RSC Adv 2011. [DOI: 10.1039/c1ra00158b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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13
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Adsorption of pepsin in octadecylamine matrix at air–water interface. Biophys Chem 2010; 146:85-91. [DOI: 10.1016/j.bpc.2009.10.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 10/16/2009] [Accepted: 10/27/2009] [Indexed: 11/18/2022]
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14
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Calvel P, Kervarrec C, Lavigne R, Vallet-Erdtmann V, Guerrois M, Rolland AD, Chalmel F, Jégou B, Pineau C. CLPH, a novel casein kinase 2-phosphorylated disordered protein, is specifically associated with postmeiotic germ cells in rat spermatogenesis. J Proteome Res 2009; 8:2953-65. [PMID: 19271754 DOI: 10.1021/pr900082m] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In a recent proteomic study of rat spermatogenesis, we identified CLPH (for Casein-Like PHosphoprotein), a new testis-specific protein expressed exclusively in postmeiotic germ cells. In situ hybridization showed that the CLPH transcript was mainly present in round spermatids, whereas the protein was specifically detected by immunohistochemistry in elongated spermatids and in residual bodies. Electron microscopy showed the protein to be mostly cytoplasmic, but also frequently associated with the mitochondrial inner membrane during the last steps of spermatid differentiation. The Clph gene was found to be present solely in mammalian genomes, in a chromosomal region syntenic to the mammalian cluster of secretory calcium-binding phosphoprotein (SCPP) genes. CLPH has several distinctive properties in common with SCPPs: calcium overlay experiments showed that CLPH was a calcium-binding protein, whereas trypsin digestion assay, circular dichroism and fluorescence experiments demonstrated its intrinsically disordered structure. We also showed that CLPH was phosphorylated in vitro and in vivo by casein kinase 2, an enzyme critical for spermatid elongation. Given the specific and strong production of CLPH during rat spermiogenesis, together with the particular biochemical properties of this protein, we suggest that CLPH is involved in the extremely complex structural rearrangements occurring in haploid germ cells during spermiogenesis.
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Affiliation(s)
- Pierre Calvel
- Inserm, U625, Rennes, Universite Rennes I, Campus de Beaulieu, IFR-140, GERHM, Rennes, F-35042, France
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15
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Secondary structure of food proteins by Fourier transform spectroscopy in the mid-infrared region. Amino Acids 2009; 38:679-90. [PMID: 19350368 DOI: 10.1007/s00726-009-0274-3] [Citation(s) in RCA: 281] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Accepted: 03/11/2009] [Indexed: 10/20/2022]
Abstract
Fourier transform spectroscopy in the mid-infrared (400-5,000 cm(-1)) (FT-IR) is being recognized as a powerful tool for analyzing chemical composition of food, with special concern to molecular architecture of food proteins. Unlike other spectroscopic techniques, it provides high-quality spectra with very small amount of protein, in various environments irrespective of the molecular mass. The fraction of peptide bonds in alpha-helical, beta-pleated sheet, turns and aperiodic conformations can be accurately estimated by analysis of the amide I band (1,600-1,700 cm(-1)) in the mid-IR region. In addition, FT-IR measurement of secondary structure highlights the mechanism of protein aggregation and stability, making this technique of strategic importance in the food proteomic field. Examples of applications of FT-IR spectroscopy in the study of structural features of food proteins critical of nutritional and technological performance are discussed.
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Johansson A, Lugand D, Rolet-Répécaud O, Mollé D, Delage MM, Peltre G, Marchesseau S, Léonil J, Dupont D. Epitope characterization of a supramolecular protein assembly with a collection of monoclonal antibodies: the case of casein micelle. Mol Immunol 2008; 46:1058-66. [PMID: 18992943 DOI: 10.1016/j.molimm.2008.09.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Revised: 09/23/2008] [Accepted: 09/24/2008] [Indexed: 11/29/2022]
Abstract
In milk, kappa-, beta-, alphas(1)- and alphas(2)-casein (CN) are associated into a supramolecular assembly, the micelle. In this work, CN micelles contained in fresh skim milk were used to produce over 100 monoclonal antibodies. The specificity of these probes was determined using libraries of synthetic peptides and peptides fractionated from tryptic hydrolysis of purified CNs. Although kappa-CN and alphas(2)-CN are minor proteins in the micelle (ratio 1:1:4:4 for kappa, alphas(2), alphas(1), beta) a proportionally high number of clones were produced towards these two proteins (32 for each), compared to 9 and 29 for alphas(1)-CN and beta-CN, respectively. Most of the beta-CN and kappa-CN epitopes were identified, while about 50% of alphas(1)-CN and alphas(2)-CN antibodies were suspected to react to conformational linear or discontinuous epitopes, since no peptide binding could be identified. Antibody binding to the phosphoserine rich regions of the three calcium sensitive CNs was weak or non-existing, suggesting them to be hidden in the micelle structure together with alphas(1)-CN. The C-terminal glycomacropeptide of kappa-CN and the C-terminal moiety of beta-CN were well exposed generating the majority of the antibodies specific for these two proteins. The two major antigenic sites of alphas(2) were alphas(2)-CN (f96-114) and (f16-35). Cross-reaction between alphas(2)-CN specific antibodies with alphas(1)-CN illustrated the tangled structure between the two proteins. Immuno-dominant epitopes identified in the present study totally differ from those known for the purified caseins suggesting they were specific for the micelle supramolecular structure.
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Affiliation(s)
- Annette Johansson
- INRA-Unité de Recherches en Technologie et Analyses Latières, BP 20089, F-39800 Poligny, France
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17
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Carbonaro M, Maselli P, Dore P, Nucara A. Application of Fourier transform infrared spectroscopy to legume seed flour analysis. Food Chem 2008. [DOI: 10.1016/j.foodchem.2007.10.045] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Gaspar AM, Appavou MS, Busch S, Unruh T, Doster W. Dynamics of well-folded and natively disordered proteins in solution: a time-of-flight neutron scattering study. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2008; 37:573-82. [PMID: 18228014 DOI: 10.1007/s00249-008-0266-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2007] [Revised: 12/19/2007] [Accepted: 01/08/2008] [Indexed: 11/28/2022]
Abstract
Casein proteins belong to the class of natively disordered proteins. The existence of disordered biologically active proteins questions the assumption that a well-folded structure is required for function. A hypothesis generally put forward is that the unstructured nature of these proteins results from the functional need of a higher flexibility. This interplay between structure and dynamics was investigated in a series of time-of-flight neutron scattering experiments, performed on casein proteins, as well as on three well-folded proteins with distinct secondary structures, namely, myoglobin (alpha), lysozyme (alpha/beta) and concanavalin A (beta). To illustrate the subtraction of the solvent contribution from the scattering spectra, we used the dynamic susceptibility spectra emphasizing the high frequency part of the spectrum, where the solvent dominates. The quality of the procedure is checked by comparing the corrected spectra to those of the dry and hydrated protein with negligible solvent contamination. Results of spectra analysis reveal differences in motional amplitudes of well-folded proteins, where beta-sheet structures appear to be more rigid than a cluster of alpha-helices. The disordered caseins display the largest conformational displacements. Moreover their global diffusion rates deviate from the expected dependence, suggesting further large-scale conformational motions.
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Affiliation(s)
- A M Gaspar
- E13, Physik Department, Technische Universität München, Lichtenberg str 1, 85747 Garching bei München, Germany.
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19
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Glomm WR, Halskau, Ø, Hanneseth AMD, Volden S. Adsorption Behavior of Acidic and Basic Proteins onto Citrate-Coated Au Surfaces Correlated to Their Native Fold, Stability, and pI. J Phys Chem B 2007; 111:14329-45. [DOI: 10.1021/jp074839d] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Beaufils S, Hadaoui-Hammoutène R, Vié V, Miranda G, Perez J, Terriac E, Henry G, Delage MM, Léonil J, Martin P, Renault A. Comparative behaviour of goat β and αs1-caseins at the air–water interface and in solution. Food Hydrocoll 2007. [DOI: 10.1016/j.foodhyd.2006.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Pihlanto A, Korhonen H. Bioactive peptides and proteins. ADVANCES IN FOOD AND NUTRITION RESEARCH 2003; 47:175-276. [PMID: 14639784 DOI: 10.1016/s1043-4526(03)47004-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Affiliation(s)
- Anne Pihlanto
- MTT Agrifood Research Finland, Food Research, 31600 Jokioinen, Finland
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22
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Chobert JM. Milk protein modification to improve functional and biological properties. ADVANCES IN FOOD AND NUTRITION RESEARCH 2003; 47:1-71. [PMID: 14639781 DOI: 10.1016/s1043-4526(03)47001-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Affiliation(s)
- Jean-Marc Chobert
- Laboratoire d'Etude des Interactions des Molécules Alimentaires Institut National de la Recherche Agronomique Rue de la Géraudière B.P. 71627, 44316 Nantés, France
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23
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Scaloni A, Perillo V, Franco P, Fedele E, Froio R, Ferrara L, Bergamo P. Characterization of heat-induced lactosylation products in caseins by immunoenzymatic and mass spectrometric methodologies. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1598:30-9. [PMID: 12147341 DOI: 10.1016/s0167-4838(02)00290-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nonenzymatic glycosylation of proteins occur during milk thermal treatment through the Maillard reaction. Immunoenzymatic and spectrometric methodologies were used to investigate caseins modification in samples submitted to different processing. As expected, protein-bound carbonyl content in raw and thermal-treated milks was positively correlated with the severity of the treatment. When immunoblotting and ELISA experiments were carried out either on isolated or whole milk proteins, carbonyl accumulation on caseins and macromolecular aggregates produced by thermal processing was evidenced. A comparative electrospray-mass spectrometry (ES-MS) analysis of different milks allowed verifying the extent of Amadori adducts on the more abundant protein components (alphas1- and beta-casein (alphas1- and beta-CN)). A combined matrix-assisted laser desorption ionization (MALDI)-MS/Edman degradation approach on enzymatic digests identified caseins modification sites. In moderately heat-treated milks, we observed that lactosylation occurred specifically at Lys-34 (alphas1-CN) and Lys-107 (beta-CN); whereas, samples subjected to more severe conditions presented modification at Lys-7, Lys-34, Lys-83, Lys-103, Lys-105, Lys-132 and Lys-193 (alphas1-CN) and at Lys-32, Lys-48, Lys-107, Lys-113 and Lys-176 (beta-CN). Differences in secondary structure of these components was assayed by circular dichroism (CD) spectroscopy.
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Affiliation(s)
- Andrea Scaloni
- Proteomics and Mass Spectrometry Laboratory, I.A.B.B.A.M., National Research Council, Naples, Italy
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CHEVALIER FRANÇOIS, CHOBERT JEANMARC, DALGALARRONDO MICHÈLE, HAERTLÉ THOMAS. CHARACTERIZATION OF THE MAILLARD REACTION PRODUCTS OF ?-LACTOGLOBULIN GLUCOSYLATED IN MILD CONDITIONS. J Food Biochem 2001. [DOI: 10.1111/j.1745-4514.2001.tb00723.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Sawyer L, Kontopidis G. The core lipocalin, bovine beta-lactoglobulin. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1482:136-48. [PMID: 11058756 DOI: 10.1016/s0167-4838(00)00160-6] [Citation(s) in RCA: 311] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The lipocalin family became established shortly after the structural similarity was noted between plasma retinol binding protein and the bovine milk protein, beta-lactoglobulin. During the past 60 years, beta-lactoglobulin has been studied by essentially every biochemical technique available and so there is a huge literature upon its properties. Despite all of these studies, no specific biological function has been ascribed definitively to the protein, although several possibilities have been suggested. During the processing of milk on an industrial scale, the unpredictable nature of the process has been put down to the presence of beta-lactoglobulin and certainly the whey protein has been implicated in the initiation of aggregation that leads to the fouling of heat exchangers. This short review of the properties of the protein will concentrate mainly on studies carried out under essentially physiological conditions and will review briefly some of the possible functions for the protein that have been described.
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Affiliation(s)
- L Sawyer
- The Structural Biochemistry Group, Institute of Cell and Molecular Biology, Mayfield University of Edinburgh, Swann Building, King's Buildings, Mayfield Road, Edinburgh EH9 3JR, UK.
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26
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Abstract
The caseins comprise the major protein component of milk of most mammals and are secreted as micelles that also carry high concentrations of calcium. They are phosphoproteins that represent the products of four genes, equivalent to those that encode the bovine alpha s1, alpha s2, beta, and kappa-caseins. There is considerable variation in the relative proportions of the particular caseins across species. The primary sequences of the alpha s1, alpha s2, and beta-caseins also show considerable species variation consistent with rapidly evolving genes that are proposed to have a common precursor. In contrast, the kappa-caseins exhibit features that demonstrate a separate origin and function where they are proposed to stabilise the micelle structure. This review focuses on comparative aspects of the caseins across a number of species for which information is now available.
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Affiliation(s)
- M R Ginger
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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Jermutus L, Guez V, Bedouelle H. Disordered C-terminal domain of tyrosyl-tRNA synthetase: secondary structure prediction. Biochimie 1999; 81:235-44. [PMID: 10385005 DOI: 10.1016/s0300-9084(99)80057-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The C-terminal domain (residues 320-419) of tyrosyl-tRNA synthetase (TyrRS) from Bacillus stearothermophilus is disordered in the crystal structure and involved in the binding of the anticodon arm of tRNA(Tyr). The sequences of 11 TyrRSs of prokaryotic or mitochondrial origins were aligned and the alignment showed the existence of conserved residues in the sequences of the C-terminal domains. A consensus could be deduced from the application of five programs of secondary structure prediction to the 11 sequences of the query set. These results suggested that the sequences of the C-terminal domains determined a precise and conserved secondary structure. They predicted that the C-terminal domain would have a mixed fold (alpha/beta or alpha+beta), with the alpha-helices in the first half of the sequence and the beta-strands mainly in its second half. Several programs of fold recognition from sequence alone, by threading onto known structures, were applied but none of them identified a type of fold that would be common to the different sequences of the query set. Therefore, the fold of the C-terminal, anticodon binding domain might be novel.
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Affiliation(s)
- L Jermutus
- Groupe d'Ingénierie des Protéines (CNRS URA 1129), Unité de Biochimie Cellulaire, Institut Pasteur, Paris, France
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Li-Chan EC. Methods to monitor process-induced changes in food proteins. An overview. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 434:5-23. [PMID: 9598186 DOI: 10.1007/978-1-4899-1925-0_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Proteins in food systems may undergo various changes in their structural properties as a consequence of processing. Whether these changes are beneficial or detrimental in terms of the nutritional, biological or functional properties of the processed system, it is important to apply analytical methods which can monitor the course of protein structural changes, in order to elucidate the underlying mechanism behind the results of different processes. Proteins are usually found in high concentrations in foods; furthermore, these proteins frequently may either initially be part of a solid food or may become insoluble due to processing. As a result, many of the traditional biochemical methods for analysis of protein structural properties in dilute solution cannot be applied directly to study food proteins. This chapter gives an overview of some potential methods which may be used to monitor the changes in quaternary, tertiary, secondary and primary structure of proteins in food systems.
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Affiliation(s)
- E C Li-Chan
- Department of Food Science, University of British Columbia, Vancouver, Canada
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29
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MADSEN J, QVIST K. Hydrolysis of Milk Protein by a Bacillus licheniformis Protease Specific for Acidic Amino Acid Residues. J Food Sci 1997. [DOI: 10.1111/j.1365-2621.1997.tb04435.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Creamer LK, MacGibbon AK. Some recent advances in the basic chemistry of milk proteins and lipids. Int Dairy J 1996. [DOI: 10.1016/0958-6946(96)85309-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Puyol P, Perez MD, Sanchez L, Ena JM, Calvo M. Uptake and passage of beta-lactoglobulin, palmitic acid and retinol across the Caco-2 monolayer. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1236:149-54. [PMID: 7794943 DOI: 10.1016/0005-2736(95)00041-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Caco-2 cell line grown on collagen coated polycarbonate membranes in bicameral chambers has been used to study the effect of the binding of palmitic acid or retinol on the uptake and passage of iodinated beta-lactoglobulin and albumin across cell monolayers. The percentage of beta-lactoglobulin transported through the monolayer was higher than that of albumin, about 50% and 30% of the total protein after 24 h of incubation, respectively. In all cases, less than 1% of protein was retained intracellularly. No differences were found in the uptake and transport of beta-lactoglobulin or albumin in the presence or absence of ligands. Furthermore, uptake and passage across Caco-2 monolayer of retinol or palmitic acid added either bound to beta-lactoglobulin or to albumin have been compared. The percentage of retinol found in the lower chamber was about 35% of the total retinol after 24 h of incubation for both proteins. However, the amount of retinol associated to cells was higher when it was added bound to beta-lactoglobulin than to albumin, about 26% and 10%, respectively. This fact suggests that the metabolic processing of retinol by Caco-2 cells is the rate-limiting step for retinol transport. The percentage of palmitic acid that crossed the monolayer was about 7%, remaining approx. 90% in the cells for beta-lactoglobulin and albumin. These data support the hypothesis that palmitic acid internalized by Caco-2 cells is mainly destined to serve the structural and energy needs. These results show evidence of retinol and palmitic uptake by Caco-2 cells when beta-lactoglobulin or albumin are the donors, and indicate that the type of binding protein does not affect the transport of both ligands through Caco-2 monolayer.
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Affiliation(s)
- P Puyol
- Facultad de Veterinaria, Universidad de Zaragoza, Spain
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32
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Pérez MD, Calvo M. Interaction of beta-lactoglobulin with retinol and fatty acids and its role as a possible biological function for this protein: a review. J Dairy Sci 1995; 78:978-88. [PMID: 7622732 DOI: 10.3168/jds.s0022-0302(95)76713-3] [Citation(s) in RCA: 197] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
beta-Lactoglobulin is the major whey protein in the milk of ruminants and some nonruminants, such as pigs and horses. Although beta-lactoglobulin was first isolated 60 yr ago, no function has been definitely ascribed to beta-lactoglobulin. Recent x-ray crystallographic studies have advanced knowledge of the structure of beta-lactoglobulin, which is homologous with that of retinol-binding protein and lipocalycins; the function of these proteins seems to be participation in the transport of small hydrophobic substances. By analogy, this protein has been suggested as having a role as a transporter of fatty acids and retinol. This review reassesses the function of beta-lactoglobulin in light of the large amount of information that has accrued in the last few years. In particular, this review concentrates upon studies of the binding of retinol and fatty acids to beta-lactoglobulin, including the binding constants and number of binding sites, the location of the binding sites, and the influence of chemical modifications in the interaction of the protein with both ligands. This study also describes studies of the influence of beta-lactoglobulin on several biological processes that may be relevant to the possible biological role of this protein.
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Affiliation(s)
- M D Pérez
- Tecnología y Bioquímica de los Alimentos, Facultad de Veterinaria, Zaragoza, Spain
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