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Sun M, Garnier L, Brighouse D, Montorfani J, Cosset E, Walker P, Pot-Kreis C, Petrova T, Muccioli G, Hugues S. 207P Impact of lymphatic vessel derived oxysterol on anti-tumor immunity. Immuno-Oncology and Technology 2022. [DOI: 10.1016/j.iotech.2022.100318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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2
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Goranova Z, Nakov G, Petrova T, Momchilova M, Khvostenko K. Improvement of the quality characteristics of semi-finished sponge cakes by using apple pomace powder. FST 2022. [DOI: 10.15673/fst.v16i1.2286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study aims to assess the effect of powdered apple pomace on the technological characteristics of batter, and on the physicochemical and sensory quality characteristics of sponge cake. Apple pomace powder (10%, 25%, and 50 %) was introduced into the sponge cake formulation, where it replaced an equivalent amount of wheat flour. Assessment of the viscous properties of the composite flour has shown that the peak viscosity ranged from 330.00 to 731.00 Brabender units (BU) and its value decreased with an increase in the mass fraction of apple pomace powder. The gelatinisation temperature for the mixtures ranged 60.50–61.7°C and slightly decreased after adding by-products of apple processing. It has been found that the specific gravity of sponge cake batter increases when pomace powder is used (from 0.72±0.02c to 0.78±0.03d), which is due to the increase in the dietary fibre. The findings have shown that the volume of the cake samples containing apple pomace was smaller than that of the control sample (245.00±6.22 cm3), and the cake with 50% of apple pomace powder had the smallest volume (215.00±7.32cm3). The highest porosity was observed in the control cake sample (66.34±1.72%), while in the cake with 25 % of apple pomace powder, this parameter was 65.15±1.07%. The water absorption capacity of the control (312.60±3.15%) is the lowest compared with that of the cakes with apple pomace powder. Adding apple pomace resulted in a more intense brownish colour of the cakes and in the pleasant fresh apple taste. The semi-finished sponge cakes with 25% and 50% of apple pomace were characterised by an attractive brown colour, small-sized, properly distributed pores in the crumb, and high sensory characteristics. It can be concluded that powdered apple pomace can be successfully used as a functional and nutritionally valuable substitute for wheat flour, without a significant deterioration in the technological quality of products.
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Angelova T, Goranova Z, Petrova T, Penov N. Effect of selected parameters on sectional expansion index and bulk density during the extrusion of chickpea instant semolina. FST 2021. [DOI: 10.15673/fst.v15i2.2107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A four-factor Response surface methodology central composite rotatable design was used to study the effect of moisture content, barrel temperature, screw speed, and feed screw speed on sectional expansion index and bulk density during extrusion of chickpea instant semolina for the purpose of instant product. The regression models for the investigated responses were highly significant (according to P-value) with satisfactory coefficients of determination (R2) 0.894 and 0.957. These results show that the predicted models for the investigated responses are adequate, indicating that the second-order polynomial model could be effectively used to represent the relationship between the selected parameters. The study showed that the expansion was influenced by moisture and temperature and it increased with increasing temperature for moisture content from 20 to 23% and after that decreased. Bulk density decreased with increasing feed moisture and barrel temperature in the extruder. The most important consequences for the science and practice resulting from the conducted research are that the resulting extrudates after grinding can be successfully used for the preparation of instant product with good characteristics, such as bulk density and sectional expansion index.
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Ionova T, Andrievskikh M, Amdiev A, Baryakh E, Chang V, Endakova A, Fadeeva N, Husainova G, Ivanov V, Kaplanov K, Kaverina O, Kiseleva M, Klitochenko T, Kurakin V, Larionova O, Lazareva D, Lepik K, Lysenko I, Melnichenko V, Mikhailova N, Minullina R, Mironov O, Misyurina E, Mochkin N, Nikitina T, Osipov Y, Petrova T, Porfirieva N, Rukavitsyn O, Safin R, Samoylova A, Shelekhova T, Sherstnev D, Simashova P, Smirnova E, Trenina N, Vasiliev E, Volodicheva E. BRENTUXIMAB VEDOTIN FOR TREATMENT IN PATIENTS WITH RELAPSED/REFRACTORY CLASSICAL HODGKIN LYMPHOMA IN A REAL WORLD SETTING: CLINICAL OUTCOMES AND IMPACT ON QUALITY OF LIFE. Hematol Oncol 2021. [DOI: 10.1002/hon.67_2881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- T. Ionova
- Multinational Center for Quality of Life Research Department of Hematology Saint Petersburg Russian Federation
| | - M. Andrievskikh
- Chelyabinsk Regional Clinical Center of Oncology and Nuclear Medicine Hematology Chelyabinsk Russian Federation
| | - A. Amdiev
- V.M. Efetov Crimean Republican Oncology Center, Hematology Simferopol Russian Federation
| | - E. Baryakh
- City Clinical Hospital №52 Hematology Moscow Russian Federation
| | - V. Chang
- Tambov Regional Oncological Clinical Center Hematological Tambov Russian Federation
| | - A. Endakova
- Kirov Research Institute of Hematology and Blood Transfusion under the Federal Medical Biological Agency Hematological Kirov Russian Federation
| | - N. Fadeeva
- Chelyabinsk Regional Clinical Center of Oncology and Nuclear Medicine Hematology Saint Petersburg Russian Federation
| | - G. Husainova
- Republican Clinical Oncology Center of the Ministry of Health of the Republic of Tatarstan, Hematological Kazan Russian Federation
| | - V. Ivanov
- Almazov National Medical Research Centre Department of Anesthesiology and Intensive Care Medicine Saint Petersburg Russian Federation
| | - K. Kaplanov
- S.P. Botkin City Clinical Hospital Hematological Department Moscow Russian Federation
| | - O. Kaverina
- Altai Regional Oncology Center Hematological Department Barnaul Russian Federation
| | - M. Kiseleva
- V.M. Efetov Crimean Republican Oncology Center, Hematology Simferopol Russian Federation
| | - T. Klitochenko
- Volgograd Regional Clinical Oncological Center Hematological Department Volgograd Russian Federation
| | - V. Kurakin
- Clinical Oncological Center, Hematological Department Omsk Russian Federation
| | - O. Larionova
- Primorskiy Regional Oncologic Center, Hematological Department Vladivostok Russian Federation
| | - D. Lazareva
- Altai Regional Oncology Center Hematological Department Barnaul Russian Federation
| | - K. Lepik
- RM Gorbacheva Research Institute of Pediatric Oncology Hematology and Transplantation, Pavlov University, Chemotherapy and Bone Marrow Transplantation Department Saint Petersburg Russian Federation
| | - I. Lysenko
- National Medical Research Centre for Oncology of the Ministry of Health of Russia, Department of Oncohematology Rostov‐on‐Don Russian Federation
| | - V. Melnichenko
- N.I. Pirogov National Medical Surgical Center Department of Hematology and Chemotherapy with a room of Bone Marrow and Hematopoietic Stem Cells Transplantation Moscow Russian Federation
| | - N. Mikhailova
- RM Gorbacheva Research Institute of Pediatric Oncology Hematology and Transplantation, Pavlov University, Chemotherapy and Bone Marrow Transplantation Department Saint Petersburg Russian Federation
| | - R. Minullina
- Republican Clinical Oncology Center of the Ministry of Health of the Republic of Tatarstan, Hematological Kazan Russian Federation
| | - O. Mironov
- Tambov Regional Oncological Clinical Center Hematological Tambov Russian Federation
| | - E. Misyurina
- City Clinical Hospital №52 Hematology Moscow Russian Federation
| | - N. Mochkin
- N.I. Pirogov National Medical Surgical Center Department of Hematology and Chemotherapy with a room of Bone Marrow and Hematopoietic Stem Cells Transplantation Moscow Russian Federation
| | - T. Nikitina
- Multinational Center for Quality of Life Research Department of Hematology Saint Petersburg Russian Federation
| | - Y. Osipov
- Almazov National Medical Research Centre Department of Oncohematology Saint Petersburg Russian Federation
| | - T. Petrova
- Republican Clinical Oncology Center of the Ministry of Health of the Republic of Tatarstan, Hematological Kazan Russian Federation
| | - N. Porfirieva
- Multinational Center for Quality of Life Research Department of Hematology Saint Petersburg Russian Federation
| | - O. Rukavitsyn
- N.N. Burdenko Main Military Clinical Hospital Hematological Center Moscow Russian Federation
| | - R. Safin
- Republican Clinical Oncology Center of the Ministry of Health of the Republic of Tatarstan, Hematological Kazan Russian Federation
| | - A. Samoylova
- N.I. Pirogov National Medical Surgical Center Department of Hematology and Chemotherapy with a room of Bone Marrow and Hematopoietic Stem Cells Transplantation Moscow Russian Federation
| | - T. Shelekhova
- Clinic of Professional Pathology and Hematology named after V.Ya. Shustov Saratov State Medical University Hematology Saratov Russian Federation
| | - D. Sherstnev
- Clinic of Professional Pathology and Hematology named after V.Ya. Shustov Saratov State Medical University Hematology Saratov Russian Federation
| | - P. Simashova
- N.N. Burdenko Main Military Clinical Hospital Hematological Center Moscow Russian Federation
| | - E. Smirnova
- N.I. Pirogov National Medical Surgical Center Department of Hematology and Chemotherapy with a room of Bone Marrow and Hematopoietic Stem Cells Transplantation Moscow Russian Federation
| | - N. Trenina
- Clinical Oncological Center, Hematological Department Omsk Russian Federation
| | - E. Vasiliev
- Regional Clinical Hospital Hematological Department Krasnoyarsk Russian Federation
| | - E. Volodicheva
- Tula Regional Clinical Hospital Hematological Department Tula Russian Federation
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Abstract
Nowadays, there is growing demand for flour-based products that only contain natural ingredients and are highly nutritional. This tendency promotes further research to find new raw materials for their production. Using by-products of pumpkin processing is a promising way to solve this problem due to their chemical content. In this research, the physicochemical and sensory properties of sponge cake enriched with pumpkin seed powder in two different quantities (5% and 10%) have been studied. Sensory evaluation of sponge cakes with pumpkin seed powder has revealed very high consumer acceptance. It has been established that the semi-finished cake with 5% of pumpkin seed powder added decreased in volume (229.00±5.17cm3), compared with the control (255.00±5.07 cm3). Higher porosity was observed in the control sample (65.62±1.41%) and in the sample with 5% of pumpkin seed powder added (64.20±1.00%). The water-absorbing capacity of the control sample (312.60±3.15%) was the lowest, compared with that of the samples containing 5 and 10% of pumpkin by-products. The lowest values of the crust chroma were in the cake samples containing 10% of pumpkin seed powder. The colour of the crust and crumb in the control was similar to that in the cake with 5% of pumpkin seed powder. An increase in the proportion of pumpkin seed powder from 0 to 10% resulted in an increase in the protein content, fibre, and total carbohydrates. The cake samples with 10% of pumpkin seed powder were the highest in protein (14.77%), fibre (2.76%), and total carbohydrates (75.15%). The results of sensory evaluation have shown that the semi-finished sponge cake enriched with 10% of pumpkin seed powder had better sensory properties, a more acceptable shape, smell, texture of the crumb, colour, and taste, compared with other samples.
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Stoilova O, Koseva N, Petrova T, Manolova N, Rashkov I, Naydenov M. Hydrolysis of Chitosan, Chitosan-Polyoxyethylene and Chitosan-Poly(2-acryloylamido-2-methylpropanesulfonic acid) by a Crude Enzyme Complex from Trichoderma viride. J BIOACT COMPAT POL 2016. [DOI: 10.1106/79tu-6c9k-ep62-n051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The degradation of chitosan using a crude enzyme complex from the soil fungus Trichoderma viride was examined in terms of temperature, pH, enzyme activity and the presence of a polymer partner. It was found that chitosan hydrolysis is not suppressed by combining it with polyoxyethylene or poly(2-acryloylamido-2-methylpropanesulfonic acid). The results on Trichoderma viride immobilized on beads imply that chitosan, as well as its polymer complexes are appropriate carriers for development of ecologically safe phytosanitary preparations.
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Affiliation(s)
| | | | - Ts. Petrova
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - N. Manolova
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - I. Rashkov
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - M. Naydenov
- Department of Microbiology, Higher Agricultural Institute, 4000 Plovdiv, Bulgaria
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Mladenova R, Petrova T, Manolova N, Ignatova M, Rashkov I, Kubisa P. Preparation, Characterization, and Biological Activity of Amides and Esters from 8-Hydroxyquinoline-2-Carboxylic Acid and Jeffamines ED® Or Poly(Ethylene Glycol)S. J BIOACT COMPAT POL 2016. [DOI: 10.1106/ad9e-dqyk-579v-ht7a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
New macromolecular chelators were synthesized under mild conditions by reaction of 8-hydroxyquinoline-2-carboxylic acid (8Q2COOH) with polyethers having amino end-groups (Jeffamines ED®) or poly(ethylene glycol)s in the presence of dicyclohexylcarbodiimide and dimethylamino-pyridine. The prepared amides (8Q2CONH-POE) and esters (8Q2COO-POE) were characterized by SEC, DSC, IR, 1H and 13C NMR spectroscopy, and MALDI-TOF mass spectrometry. It was found that the polyethers had 8-hydroxy-2-quinolinyl end groups and formed complexes with Fe3+ ions. The obtained complexes were studied with IR spectroscopy and DSC. The plant tests showed that the Fe3+ complex of 8Q2CONH-POE2000 had high efficacy in the remedy of iron-deficient maize plants under hydroponic conditions.
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Affiliation(s)
| | - Ts. Petrova
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - N. Manolova
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | | | - I. Rashkov
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - P. Kubisa
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
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Abstract
Three types of polymer networks of chitosan and polyacrylamide (PAAm) – semi-interpenetrating networks (semi-IPNs) of chitosan and crosslinked PAAm ( net-PAAm– t-chitosan), semi-IPNs of PAAm and crosslinked chitosan ( net-chitosan– t-PAAm), and interpenetrating networks (IPNs) of crosslinked chitosan and crosslinked PAAm ( net-PAAm– net-chitosan) were prepared. Chitosan, in a two-fold molar excess to PAAm, provided pH-sensitivity to hydrogel networks. The amount of the crosslinking agent did not have much influence on the microhardness of network films, while higher contents of PAAm increased it. The equilibrium degree of swelling of the hydrogels had the highest values at pH 4 and decreased on increasing pH (pH 7, pH 9) or the ionic strength of the medium as well as with increasing of the degree of crosslinking. The networks in which chitosan was crosslinked, – semi-IPNs net-chitosan– t-PAAm and IPNs net-chitosan– net-PAAm, showed five cycles of completely reversible swelling.
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Affiliation(s)
- P. Bonina
- Laboratory of Bioactive Polymers, Institute of Polymers Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Ts. Petrova
- Laboratory of Bioactive Polymers, Institute of Polymers Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - N. Manolova
- Laboratory of Bioactive Polymers, Institute of Polymers Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
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Bonina P, Petrova T, Manolova N, Rashkov I, Naydenov M. pH-Sensitive Hydrogels Composed of Chitosan and Polyacrylamide: Enzymatic Degradation. J BIOACT COMPAT POL 2016. [DOI: 10.1177/0883911504044455] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The enzymatic degradation of three types of pH-sensitive hydrogels, composed of the natural polyaminosaccharide chitosan and polyacrylamide, was studied. The weight of the films that were made with net-PAAm- i-chitosan, net-chitosan- i-PAAm and net-chitosan- net-PAAm decreased in the presence of the Trichoderma viride enzyme complex ; thus, the chitosan in the composite retained its degradability after crosslinking. The rate of enzymatic degradation depended on the structure of the network, on the amount of crosslinking agents, on the pH of the medium and on the temperature. Crosslinked chitosan alone degraded slower than net-chitosan- i-PAAm; this was attributed to the facilitated penetration of enzyme by the water-soluble PAAm in the semi-IPNs. T. viride embedded in chitosan/PAAm films or beads developed and reproduced normally. However, T. viride embedded in net-chitosani-PAAm developed considerably slower, and development was not detected in the case of net-PAAm- i-chitosan. All of the networks proved to be appropriate carriers of Bacillus subtilis.
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Affiliation(s)
- P. Bonina
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - T. Petrova
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - N. Manolova
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - I. Rashkov
- Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - M. Naydenov
- Department of Microbiology, Agricultural University, 4000 Plovdiv, Bulgaria
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Howard EI, Guillot B, Blakeley MP, Haertlein M, Moulin M, Mitschler A, Cousido-Siah A, Fadel F, Valsecchi WM, Tomizaki T, Petrova T, Claudot J, Podjarny A. High-resolution neutron and X-ray diffraction room-temperature studies of an H-FABP-oleic acid complex: study of the internal water cluster and ligand binding by a transferred multipolar electron-density distribution. IUCrJ 2016; 3:115-26. [PMID: 27006775 PMCID: PMC4775160 DOI: 10.1107/s2052252515024161] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 12/16/2015] [Indexed: 05/24/2023]
Abstract
Crystal diffraction data of heart fatty acid binding protein (H-FABP) in complex with oleic acid were measured at room temperature with high-resolution X-ray and neutron protein crystallography (0.98 and 1.90 Å resolution, respectively). These data provided very detailed information about the cluster of water molecules and the bound oleic acid in the H-FABP large internal cavity. The jointly refined X-ray/neutron structure of H-FABP was complemented by a transferred multipolar electron-density distribution using the parameters of the ELMAMII library. The resulting electron density allowed a precise determination of the electrostatic potential in the fatty acid (FA) binding pocket. Bader's quantum theory of atoms in molecules was then used to study interactions involving the internal water molecules, the FA and the protein. This approach showed H⋯H contacts of the FA with highly conserved hydrophobic residues known to play a role in the stabilization of long-chain FAs in the binding cavity. The determination of water hydrogen (deuterium) positions allowed the analysis of the orientation and electrostatic properties of the water molecules in the very ordered cluster. As a result, a significant alignment of the permanent dipoles of the water molecules with the protein electrostatic field was observed. This can be related to the dielectric properties of hydration layers around proteins, where the shielding of electrostatic interactions depends directly on the rotational degrees of freedom of the water molecules in the interface.
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Affiliation(s)
- E. I. Howard
- Department of Integrative Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre de Biologie Intégrative, CNRS, INSERM, UdS, 1 rue Laurent Fries, 67404 Illkirch CEDEX, France
- Instituto de Fisica de Liquidos y Sistemas Biologicos, CONICET, UNLP, Calle 59 No. 789, La Plata, Argentina
| | - B. Guillot
- CNRS and Université de Lorraine, Laboratoire CRM2, UMR 7036, Vandoeuvre-lès-Nancy, F-54506, France
| | - M. P. Blakeley
- Institut Laue–Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
| | - M. Haertlein
- ILL–EMBL Deuteration Laboratory, Partnership for Structural Biology, 71 avenue des Martyrs, Grenoble 38000, France
| | - M. Moulin
- ILL–EMBL Deuteration Laboratory, Partnership for Structural Biology, 71 avenue des Martyrs, Grenoble 38000, France
| | - A. Mitschler
- Department of Integrative Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre de Biologie Intégrative, CNRS, INSERM, UdS, 1 rue Laurent Fries, 67404 Illkirch CEDEX, France
| | - A. Cousido-Siah
- Department of Integrative Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre de Biologie Intégrative, CNRS, INSERM, UdS, 1 rue Laurent Fries, 67404 Illkirch CEDEX, France
| | - F. Fadel
- Department of Integrative Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre de Biologie Intégrative, CNRS, INSERM, UdS, 1 rue Laurent Fries, 67404 Illkirch CEDEX, France
| | - W. M. Valsecchi
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, Junín 956, C1113AAD, Buenos Aires, Argentina
| | - Takashi Tomizaki
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - T. Petrova
- Institute of Mathematical Problems of Biology, Russian Academy of Sciences, Pushchino 142290, Russian Federation
| | - J. Claudot
- CNRS and Université de Lorraine, Laboratoire CRM2, UMR 7036, Vandoeuvre-lès-Nancy, F-54506, France
| | - A. Podjarny
- Department of Integrative Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre de Biologie Intégrative, CNRS, INSERM, UdS, 1 rue Laurent Fries, 67404 Illkirch CEDEX, France
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Velinov N, Petrova T, Tsoncheva T, Genova I, Koleva K, Kovacheva D, Mitov I. Auto-combustion synthesis, Mössbauer study and catalytic properties of copper-manganese ferrites. ACTA ACUST UNITED AC 2016. [DOI: 10.1007/s10751-016-1222-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Fisher SJ, Blakeley MP, Howard EI, Petit-Haertlein I, Haertlein M, Mitschler A, Cousido-Siah A, Salvay AG, Popov A, Muller-Dieckmann C, Petrova T, Podjarny A. Perdeuteration: improved visualization of solvent structure in neutron macromolecular crystallography. ACTA ACUST UNITED AC 2014; 70:3266-72. [DOI: 10.1107/s1399004714021610] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 09/30/2014] [Indexed: 11/10/2022]
Abstract
The 1.8 Å resolution neutron structure of deuterated type III antifreeze protein in which the methyl groups of leucine and valine residues are selectively protonated is presented. Comparison between this and the 1.85 Å resolution neutron structure of perdeuterated type III antifreeze protein indicates that perdeuteration improves the visibility of solvent molecules located in close vicinity to hydrophobic residues, as cancellation effects between H atoms of the methyl groups and nearby heavy-water molecules (D2O) are avoided.
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13
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Petrova T, Bezsudnova EY, Boyko KM, Mardanov AV, Polyakov KM, Volkov VV, Kozin M, Ravin NV, Shabalin IG, Skryabin KG, Stekhanova TN, Kovalchuk MV, Popov VO. ATP-dependent DNA ligase from Thermococcus sp. 1519 displays a new arrangement of the OB-fold domain. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:1440-7. [PMID: 23192021 PMCID: PMC3509962 DOI: 10.1107/s1744309112043394] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 10/18/2012] [Indexed: 11/10/2022]
Abstract
DNA ligases join single-strand breaks in double-stranded DNA by catalyzing the formation of a phosphodiester bond between adjacent 5'-phosphate and 3'-hydroxyl termini. Their function is essential for maintaining genome integrity in the replication, recombination and repair of DNA. High flexibility is important for the function of DNA ligase molecules. Two types of overall conformations of archaeal DNA ligase that depend on the relative position of the OB-fold domain have previously been revealed: closed and open extended conformations. The structure of ATP-dependent DNA ligase from Thermococcus sp. 1519 (LigTh1519) in the crystalline state determined at a resolution of 3.02 Å shows a new relative arrangement of the OB-fold domain which is intermediate between the positions of this domain in the closed and the open extended conformations of previously determined archaeal DNA ligases. However, small-angle X-ray scattering (SAXS) measurements indicate that in solution the LigTh1519 molecule adopts either an open extended conformation or both an intermediate and an open extended conformation with the open extended conformation being dominant.
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Affiliation(s)
- T Petrova
- Bach Institute of Biochemistry, RAS, Leninsky pr. 33, Moscow 119071, Russian Federation.
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14
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Petrova T, Lunin V, Ginell S, Mitschler A, Kim Y, Joachimiak G, Cousido-Siah A, Hazemann I, Podjarny A, Lazarski K, Joachimiak A. X-ray-induced overall structural changes in a protein molecule at cryogenic temperatures. Acta Crystallogr A 2012. [DOI: 10.1107/s0108767312094810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
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15
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Podjarny A, Blakeley MP, Haertlein M, Petit-Haertlein I, Hazemann I, Mitschler A, Cousido-Siah A, Fisher SJ, Salvay AG, Muller-Dieckmann C, Popov A, Afonine P, Ventura O, Cachau R, Ginell S, Joachimiak A, Meilleur F, Petrova T, Myles D, Howard EI. Protein neutron crystallography with 'tiny' crystals of fully deuterated proteins. Acta Crystallogr A 2012. [DOI: 10.1107/s0108767312098261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Podjarny A, Blakeley MP, Petit-Haertlein I, Haertlein M, Cousido-Siah A, Petrova T, Howard EI. Neutron structure of type-III antifreeze protein leads to ice interface model. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311095523] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Petrova T, Ginell S, Mitschler A, Kim Y, Lunin VY, Joachimiak G, Cousido-Siah A, Hazemann I, Podjarny A, Lazarski K, Joachimiak A. X-ray-induced cooperative atomic movements in protein crystals. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311083449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Affiliation(s)
- T. Petrova
- Institute of Atmospheric Optics SB RAS , Tomsk, Russia
| | | | - V. Serdyukov
- Institute of Atmospheric Optics SB RAS , Tomsk, Russia
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- Institute of Atmospheric Optics SB RAS , Tomsk, Russia
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Podjarny AD, Mitschler A, Hazemann I, Petrova T, Ruiz F, Howard E, Darmanin C, Chung R, Schneider TR, Sanishvili R, Schulze-Briesse C, Tomizaki T, Van Zandt M, Oka M, Joachimiak A, El-Kabbani O. Inhibitor binding to aldose reductase studied at subatomic resolution. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305094845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Podjarny A, Mitschler A, Hazemann I, Petrova T, Ruiz F, Blakeley M, Dauvergne MT, Meilleur F, Van Zandt M, Ginell S, Joachimiak A, Myles D. Neutron diffraction structure of fully deuterated aldose reductase: a necessary complement to X-ray ultra-high-resolution structures. Acta Crystallogr A 2004. [DOI: 10.1107/s0108767304096941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Mitschler A, Ginell S, Petrova T, Hazemann I, Cousido A, Ruiza F, Van Zandt M, Joachimiak A, Podjarny A. X-ray structures of aldose reductase-inhibitor complexes at 0.9 Å resolution from LN2-cryocooled crystals measured at 10 K. Acta Crystallogr A 2004. [DOI: 10.1107/s0108767304096606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gousterova A, Stankova I, Christov P, Petrova T, Nedkov P. Comparison of Some Preparations, Obtained from Waste Yeast Cells for their Ability to Stimulate Microorganism Growth. BIOTECHNOL BIOTEC EQ 2003. [DOI: 10.1080/13102818.2003.10819215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Lerer B, Macciardi F, Segman RH, Adolfsson R, Blackwood D, Blairy S, Del Favero J, Dikeos DG, Kaneva R, Lilli R, Massat I, Milanova V, Muir W, Noethen M, Oruc L, Petrova T, Papadimitriou GN, Rietschel M, Serretti A, Souery D, Van Gestel S, Van Broeckhoven C, Mendlewicz J. Variability of 5-HT2C receptor cys23ser polymorphism among European populations and vulnerability to affective disorder. Mol Psychiatry 2001; 6:579-85. [PMID: 11526472 DOI: 10.1038/sj.mp.4000883] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2000] [Revised: 01/11/2001] [Accepted: 01/16/2001] [Indexed: 11/08/2022]
Abstract
Substantial evidence supports a role for dysfunction of brain serotonergic (5-HT) systems in the pathogenesis of major affective disorder, both unipolar (recurrent major depression) and bipolar.(1) Modification of serotonergic neurotransmission is pivotally implicated in the mechanism of action of antidepressant drugs(2) and also in the action of mood stabilizing agents, particularly lithium carbonate.(3) Accordingly, genes that code for the multiple subtypes of serotonin receptors that have been cloned and are expressed in brain,(4) are strong candidates for a role in the genetic etiology of affective illness. We examined a structural variant of the serotonin 2C (5-HT2C) receptor gene (HTR2C) that gives rise to a cysteine to serine substitution in the N terminal extracellular domain of the receptor protein (cys23ser),(5) in 513 patients with recurrent major depression (MDD-R), 649 patients with bipolar (BP) affective disorder and 901 normal controls. The subjects were drawn from nine European countries participating in the European Collaborative Project on Affective Disorders. There was significant variation in the frequency of the HT2CR ser23 allele among the 10 population groups included in the sample (from 24.6% in Greek control subjects to 9.2% in Scots, chi(2) = 20.9, df 9, P = 0.01). Logistic regression analysis demonstrated that over and above this inter-population variability, there was a significant excess of HT2CR ser23 allele carriers in patients compared to normal controls that was demonstrable for both the MDD (chi(2) = 7.34, df 1, P = 0.006) and BP (chi(2) = 5.45, df 1, P = 0.02) patients. These findings support a possible role for genetically based structural variation in 5-HT2C receptors in the pathogenesis of major affective disorder.
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Affiliation(s)
- B Lerer
- Biological Psychiatry Laboratory, Hadassah Medical Organization, Jerusalem, Israel.
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Nedelchev L, Nikolova L, Todorov T, Petrova T, Tomova N, Dragostinova V, Ramanujam PS, Hvilsted S. Light propagation through photoinduced chiral structures in azobenzene-containing polymers. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/1464-4258/3/4/313] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Petrova T, Benova E, Petrov G, Zhelyazkov I. Self-consistent axial modeling of surface-wave-produced discharges at low and intermediate pressures. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1999; 60:875-86. [PMID: 11969832 DOI: 10.1103/physreve.60.875] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/1998] [Indexed: 04/18/2023]
Abstract
A model for description of the axial structure of a surface-wave-produced and -sustained plasma based on numerical calculation of a complete set of electrodynamic and kinetic equations is presented. The model includes a self-consistent solution to the electron Boltzmann equation, a set of particle balance equations for electrons, excited atoms, atomic and molecular ions, as well as Maxwell's equations with appropriate boundary conditions. A gas thermal balance equation is used to predict the neutral gas temperature self-consistently. Precise calculations of discharge characteristics of an argon plasma column sustained by an azimuthally symmetric surface wave at low and intermediate gas pressures have been performed. A comparison with available experimental data is done in order to test the validity of the model.
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Affiliation(s)
- T Petrova
- Faculty of Physics, Sofia University, BG-1164 Sofia, Bulgaria
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Petrova T, Manolova N, Rashkov I, Mincheva Z, Kalcheva V. Synthesis and Characterization of Poly(Oxyethylene)S with (2-Benzoxazolon-3-yl)Acetyl End-Groups. Complex Formation with Polycarboxylic Acids. Journal of Macromolecular Science, Part A 1998. [DOI: 10.1080/10601329808007316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Flaud J, Camy-Peyret C, Bykov A, Naumenko O, Petrova T, Scherbakov A, Sinitsa L. The Water Vapor Linestrengths between 11 600 and 12 750 cm-1. J Mol Spectrosc 1997; 185:211-221. [PMID: 9398557 DOI: 10.1006/jmsp.1997.7377] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The water vapor linestrengths in the region of the 3nu + delta resonance polyad of interacting vibrational states (the corresponding upper states are (310), (211), (112), (013), (131), (230), (032), and (051)) have been analyzed leading to accurate dipole moment transition parameters. The effective rotational Hamiltonian constants used to calculate the vibration-rotation wavefunctions (J.-M. Flaud, C. Camy-Peyret, A. Bykov, O. Naumenko, T. Petrova, A. Scherbakov, L. Sinitsa, 1994. J. Mol. Spectrosc. 183, 300-309) take into account both strong centrifugal distortion effects and dark states presence. These effects are known to be important for the highly excited vibrational states of water-like molecules. The input data set included the line intensities measured by Toth (R. Toth, 1994. J. Mol. Spectrosc. 166, 176-183) and the line intensities of the weak bands 2nu1 + 3nu2, 3nu2 + 2nu3, and 3nu1 + nu2 derived from peak absorptions of a spectrum recorded at a pressure of 17.0 Torr and a path length of 434 m. The parameters of the effective dipole moment operator determined by least square fitting give a very satisfactory agreement with experimental values since the mean error for the 876 experimental linestrengths is only 3.9%. It is worth noticing that such an agreement could be reached only because high-order resonance couplings with dark states were explicitly taken into account. Copyright 1997 Academic Press. Copyright 1997Academic Press
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Affiliation(s)
- J Flaud
- Laboratoire de Photophysique Moleculaire, CNRS, Universite de Paris-Sud, Campus d'Orsay, Bat. 210, Orsay Cedex, 91405, France
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Flaud J, Camy-Peyret C, Bykov A, Naumenko O, Petrova T, Scherbakov A, Sinitsa L. The High-Resolution Spectrum of Water Vapor between 11 600 and 12 750 cm-1. J Mol Spectrosc 1997; 183:300-309. [PMID: 9252301 DOI: 10.1006/jmsp.1997.7275] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The absorption spectrum of water vapor has been recorded between 11 600 and 12 750 cm-1 with a Fourier transform spectrometer (Kitt Peak, Az) at a resolution of 0.012 cm-1 and with a path length of 434 m. The line assignment has led to the determination of 506 accurate energy levels of the (310) (211), (112), (013), (230), (131), (032), and (051) vibrational states which belong to the so-called 3nu + delta resonance polyad. The rotational energy levels obtained are on the average in agreement with those reported recently by R. Toth (J. Mol. Spectrosc. 166, 176-183 (1994)) for the strong bands, but there are differences for high J levels or weak bands levels (about 15% of all levels). The experimental rotational energy levels have been fitted using Pade-Borel approximants and a set of 104 vibrational energies and rotational, resonance, and centrifugal distortion constants for the (310), (211), (112), (013), (230), (131), (032), and (051) vibrational states have been determined.
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Affiliation(s)
- J Flaud
- CNRS, Universite de Paris-Sud, Bat. 210, Orsay Cedex, 91405, France
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Prêcheur B, Cox JA, Petrova T, Mispelter J, Craescu CT. Nereis sarcoplasmic Ca2+-binding protein has a highly unstructured apo state which is switched to the native state upon binding of the first Ca2+ ion. FEBS Lett 1996; 395:89-94. [PMID: 8849695 DOI: 10.1016/0014-5793(96)01007-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
NSCP, a sarcoplasmic Ca2+/Mg2+-binding protein from Nereis diversicolor, shows an allosteric change during Ca2+ binding and a high positive cooperativity for Mg2+ binding. Here we report the results of CD and NMR experiments aiming to characterize the apo state and the Ca2+-induced conformational changes in this protein. Circular dichroism spectra of the apo form are indicative of a reduced helical structure. In contrast, NMR spectra show no element of regular secondary or tertiary structure. Addition of one Ca2+ determines large spectral changes bringing the molecule in a conformation which is very close to the native three Ca2+ state. Addition of the second and third Ca2+ shifts this equilibrium progressively towards the liganded conformation but affects only minimally the spectrum of the liganded species.
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Affiliation(s)
- B Prêcheur
- Institut National de la Santé et de la Recherche Médicale, Institut Curie, Orsay, France
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Abstract
Troponin C (TnC) from amphioxus (Protochordate) was purified and its primary structure determined. Unlike the case of vertebrates and other invertebrates, amphioxus TnC is found in the soluble fraction after extractions at physiological ionic strength in the presence of Ca2+. Edman sequencing combined with mass spectroscopy indicate that the protein contains 163 amino acid residues. It possesses an acetylated N-terminus (although a small percentage has a free Ser N-terminus) and either epsilon-N-methyllysine or epsilon-N-dimethyllysine in position 20. It displays about 50% sequence identity with vertebrate skeletal-muscle and cardiac-muscle TnC, 44% with TnC of sea squirt, also a Protochordate, and 30% with other invertebrate TnC. Like vertebrate TnC, amphioxus TnC contains a N-terminal alpha-helix plus the usual four ancestral Ca(2+)-binding regions, but analysis of the sequence suggests that the fourth site is not functional. Flow dialysis shows that amphioxus TnC binds three Ca2+ with the mean apparent affinity constant K' of 3.4 +/- 1.5 10(5) M-1. No cooperativity exists between the sites, and the presence of up to 10 mM Mg2+ does not influence the Ca(2+)-binding isotherm, indicating that the metal-binding sites are Ca(2+)-specific at physiological Mg2+ concentrations. It forms a Ca(2+)-dependent, 1:1 complex with melittin and rabbit or crayfish troponin I (TnI). Amphioxus TnC possesses one Trp residue in position 151 and one at the C-terminus. Trp fluorescence suggests that one or both residues are solvent-exposed in the metal-free form and efficiently shielded in the Ca2+ form. Although Mg2+ has no effect on the Ca2+ binding, the Trp fluorescence is influenced by millimolar Mg2+, suggesting the presence of one or more independent Mg(2+)-binding site(s). A phylogenetic analysis clearly shows that amphioxus TnC is positioned on the branch of the Chordates, but at a distance from the vertebrate TnC. Its place on the phylogenetic tree is in accordance with the consensus evolutionary phylogeny.
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Affiliation(s)
- T Takagi
- Biological Institute, Faculty of Science, Tohoku University, Sendai, Japan
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Manolova N, Stefanova R, Petrova T, Rashkov I. Ultraviolet and 1H-NMR studies on the products of the chemical modification of α,ω-dichloropoly(oxyethylene) with potassium 5-nitro-8-quinolinolate. Eur Polym J 1993. [DOI: 10.1016/0014-3057(93)90133-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Durussel I, Luan-Rilliet Y, Petrova T, Takagi T, Cox JA. Cation binding and conformation of tryptic fragments of Nereis sarcoplasmic calcium-binding protein: calcium-induced homo- and heterodimerization. Biochemistry 1993; 32:2394-400. [PMID: 8443179 DOI: 10.1021/bi00060a034] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Nereis sarcoplasmic calcium-binding protein (NSCP) is a compact 20-kDa protein that competitively binds three Ca2+ or Mg2+ ions and displays strong positive cooperativity. Its three-dimensional structure is known. It thus constitutes a good model for the study of intramolecular information transduction. Here we probed its domain structure and interaction between domains using fragments obtained by controlled proteolysis. The metal-free form, but not the Ca2+ or Mg2+ form, is sensitive to trypsin proteolysis and is preferentially cleaved at two peptide bonds in the middle of the protein. The N-terminal fragment 1-80 (T1-80) and the C-terminal fragment 90-174 (T90-174) were purified to electrophoretic homogeneity. T1-80, which consists of a paired EF-hand domain, binds one Ca2+ with Ka = 3.1 x 10(5) M-1; entropy increase is the main driving force of complex formation. Circular dichroism indicates that T1-80 is rich in secondary structure, irrespective of the Ca2+ saturation. Ca2+ binding provokes a difference spectrum which is similar to that observed in the intact protein. These data suggest that this N-terminal domain constitutes the stable structural nucleus in NSCP to which the first Ca2+ binds. T90-174 binds two Ca2+ ions with Ka = 3.2 x 10(4) M-1; the enthalpy change contributes predominantly to the binding process. Metal-free T90-174 is mostly in random coil but converts to an alpha-helical-rich conformation upon Ca2+ binding. Ca2+ binding to T1-80 provokes a red-shift and intensity decrease of the Trp fluorescence but a blue-shift and intensity increase in T90-174.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- I Durussel
- Department of Biochemistry, University of Geneva, Switzerland
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