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Trojanowska D, Suarato G, Braccia C, Armirotti A, Fiorentini F, Athanassiou A, Perotto G. Wool Keratin Nanoparticle-Based Micropatterns for Cellular Guidance Applications. ACS APPLIED NANO MATERIALS 2022; 5:15272-15287. [PMID: 36338329 PMCID: PMC9624257 DOI: 10.1021/acsanm.2c03116] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
The waste stream of low-grade wool is an underutilized source of keratin-rich materials with appropriate methods for upcycling into high value-added products still being an open challenge. In the present work, keratins were precipitated from their water solution to produce hierarchical keratin particles via isoelectric precipitation. Matrix-assisted laser desorption/ionization coupled with time-of-flight tandem mass spectrometry analysis (MALDI-TOF/TOF MS/MS) showed the presence of the amino acid sequence leucine-aspartic acid-valine (LDV) in the extracted keratin. This well-known cell adhesion motif is recognized by the cell adhesion molecule α4β1 integrin. We showed that keratin particles had this tripeptide exposed on the surface and that it could be leveraged, via patterns obtained with microcontact printing, to support and facilitate dermal fibroblast cell adhesion and direct their growth orientation. The zeta potential, isoelectric point, morphological structures, chemical composition, and biocompatibility of keratin particles and the influence of the surfactant sodium dodecyl sulfate (SDS) were investigated. An appropriate ink for microcontact printing of the keratin particles was developed and micron-sized patterns were obtained. Cells adhered preferentially to the patterns, showing how this strategy could be used to functionalize biointerfaces.
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Affiliation(s)
- Dagmara
J. Trojanowska
- Istituto
Italiano di Tecnologia, Smart Materials Group, Via Morego, 30, 16163Genova, Italy
- Department
of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125Milan, Italy
| | - Giulia Suarato
- Istituto
Italiano di Tecnologia, Smart Materials Group, Via Morego, 30, 16163Genova, Italy
- Istituto
Italiano di Tecnologia, Translational Pharmacology Facility, Via Morego, 30, 16163Genova, Italy
| | - Clarissa Braccia
- Istituto
Italiano di Tecnologia, Analytical Chemistry Facility, Via Morego, 30, 16163Genova, Italy
| | - Andrea Armirotti
- Istituto
Italiano di Tecnologia, Analytical Chemistry Facility, Via Morego, 30, 16163Genova, Italy
| | - Fabrizio Fiorentini
- Istituto
Italiano di Tecnologia, Smart Materials Group, Via Morego, 30, 16163Genova, Italy
| | - Athanassia Athanassiou
- Istituto
Italiano di Tecnologia, Smart Materials Group, Via Morego, 30, 16163Genova, Italy
| | - Giovanni Perotto
- Istituto
Italiano di Tecnologia, Smart Materials Group, Via Morego, 30, 16163Genova, Italy
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Poboinev VV, Khrustalev VV, Khrustaleva TA, Kasko TE, Popkov VD. The PentUnFOLD algorithm as a tool to distinguish the dark and the light sides of the structural instability of proteins. Amino Acids 2022; 54:1155-1171. [PMID: 35294674 PMCID: PMC8924573 DOI: 10.1007/s00726-022-03153-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 02/14/2022] [Indexed: 12/12/2022]
Abstract
Intrinsically disordered proteins are frequently involved in important regulatory processes in the cell thanks to their ability to bind several different targets performing sometimes even opposite functions. The PentUnFOLD algorithm is a physicochemical method that is based on new propensity scales for disordered, nonstable and stable elements of secondary structure and on the counting of stabilizing and destabilizing intraprotein contacts. Unlike other methods, it works with a PDB file, and it can determine not only those fragments of alpha helices, beta strands, and random coils that can turn into disordered state (the “dark” side of the disorder), but also nonstable regions of alpha helices and beta strands which are able to turn into random coils (the “light” side), and vice versa (H ↔ C, E ↔ C). The scales have been obtained from structural data on disordered regions from the middle parts of amino acid sequences only, and not on their expectedly disordered N- and C-termini. Among other tendencies we have found that regions of both alpha helices and beta strands that can turn into the disordered state are relatively enriched in residues of Ala, Met, Asp, and Lys, while regions of both alpha helices and beta strands that can turn into random coil are relatively enriched in hydrophilic residues, and Cys, Pro, and Gly. Moreover, PentUnFOLD has the option to determine the effect of secondary structure transitions on the stability of a given region of a protein. The PentUnFOLD algorithm is freely available at http://3.17.12.213/pent-un-fold and http://chemres.bsmu.by/PentUnFOLD.htm.
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Affiliation(s)
| | | | - Tatyana Aleksandrovna Khrustaleva
- Biochemical Group of the Multidisciplinary Diagnostic Laboratory, Institute of Physiology of the National Academy of Sciences of Belarus, Minsk, Belarus
| | - Tihon Evgenyevich Kasko
- Department of General Chemistry, Belarusian State Medical University, Dzerzinskogo 83, Minsk, Belarus
| | - Vadim Dmitrievich Popkov
- Department of General Chemistry, Belarusian State Medical University, Dzerzinskogo 83, Minsk, Belarus
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3
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Khrustalev VV, Kordyukova LV, Arutyunyan AM, Poboinev VV, Khrustaleva TA, Stojarov AN, Baratova LA, Sapon AS, Lugin VG. The cytoplasmic tail of influenza A/H1N1 virus hemagglutinin is β-structural. J Biomol Struct Dyn 2020; 40:4642-4661. [PMID: 33317396 DOI: 10.1080/07391102.2020.1860827] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Influenza A/H1N1 virus hemagglutinin (HA) is an integral type I glycoprotein that contains a large glycosylated ectodomain, a transmembrane domain, and a cytoplasmic tail (CT) of 10-14 amino acid residues. There are absolutely no data on the secondary or tertiary structure of the HA CT, which is important for virus pathogenesis. Three highly conserved cysteines are post-translationally modified by the attachment of fatty acid residues that pin the CT to the lipid membrane inside the virion. We applied circular dichroism (CD) and fluorescence spectroscopy analysis to examine four synthetic peptides corresponding to 14-15 C-terminal residues of H1 subtype HA (NH2-WMCSNGSLQCRICI-COOH; NH2-FWMCSNGSLQCRICI-COOH), with free or acetaminomethylated cysteines, in the reduced or non-reduced state, at various pH values and temperatures. The CD analysis detected the formation of a β-structure (30-65% according to the new BeStSel algorithm), in addition to an unstructured random coil, in every peptide in various conditions. It was completely or partially recognized as an antiparallel β-structure that was also confirmed by the multi-bounce Horizontal Attenuated Total Reflectance Fourier Transformed Infrared (HATR-FTIR) spectroscopy analysis. According to the experimental data, as well as 3 D modeling, we assume that the amino acid sequence corresponding to the HA CT may form a short antiparallel β-structure under the lipid membrane within a virion.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | - Larisa V Kordyukova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alexander M Arutyunyan
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Victor V Poboinev
- Department of General Chemistry, Belarusian State Medical University, Minsk, Belarus
| | - Tatyana A Khrustaleva
- Biochemical group of the Multidisciplinary Diagnostic Laboratory, Institute of Physiology of the National Academy of Sciences of Belarus, Minsk, Belarus
| | - Aleksander N Stojarov
- Department of Radiation Medicine and Ecology, Belarusian State Medical University, Minsk, Belarus
| | - Lyudmila A Baratova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alena S Sapon
- Center for Physical and Chemical Research Methods, Belarusian State Technological University, Minsk, Belarus
| | - Valery G Lugin
- Center for Physical and Chemical Research Methods, Belarusian State Technological University, Minsk, Belarus
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4
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Khrustalev VV. Random Coils of Proteins Situated Between a Beta Strand and an Alpha Helix Demonstrate Decreased Solvent Accessibility. Protein J 2020; 39:308-317. [DOI: 10.1007/s10930-020-09905-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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5
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Du MZ, Zhang C, Wang H, Liu S, Wei W, Guo FB. The GC Content as a Main Factor Shaping the Amino Acid Usage During Bacterial Evolution Process. Front Microbiol 2018; 9:2948. [PMID: 30581420 PMCID: PMC6292993 DOI: 10.3389/fmicb.2018.02948] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 11/16/2018] [Indexed: 11/13/2022] Open
Abstract
Understanding how proteins evolve is important, and the order of amino acids being recruited into the genetic codons was found to be an important factor shaping the amino acid composition of proteins. The latest work about the last universal common ancestor (LUCA) makes it possible to determine the potential factors shaping amino acid compositions during evolution. Those LUCA genes/proteins from Methanococcus maripaludis S2, which is one of the possible LUCA, were investigated. The evolutionary rates of these genes positively correlate with GC contents with P-value significantly lower than 0.05 for 94% homologous genes. Linear regression results showed that compositions of amino acids coded by GC-rich codons positively contribute to the evolutionary rates, while these amino acids tend to be gained in GC-rich organisms according to our results. The first principal component correlates with the GC content very well. The ratios of amino acids of the LUCA proteins coded by GC rich codons positively correlate with the GC content of different bacteria genomes, while the ratios of amino acids coded by AT rich codons negatively correlate with the increase of GC content of genomes. Next, we found that the recruitment order does correlate with the amino acid compositions, but gain and loss in codons showed newly recruited amino acids are not significantly increased along with the evolution. Thus, we conclude that GC content is a primary factor shaping amino acid compositions. GC content shapes amino acid composition to trade off the cost of amino acids with bases, which could be caused by the energy efficiency.
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Affiliation(s)
- Meng-Ze Du
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | | | - Huan Wang
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Shuo Liu
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Wen Wei
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Feng-Biao Guo
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
- Centre for Informational Biology, University of Electronic Science and Technology of China, Chengdu, China
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6
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Khrustalev VV, Khrustaleva TA, Poboinev VV. Amino acid content of beta strands and alpha helices depends on their flanking secondary structure elements. Biosystems 2018; 168:45-54. [DOI: 10.1016/j.biosystems.2018.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 04/21/2018] [Accepted: 04/23/2018] [Indexed: 12/17/2022]
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7
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Adrian-Segarra JM, Schindler N, Gajawada P, Lörchner H, Braun T, Pöling J. The AB loop and D-helix in binding site III of human Oncostatin M (OSM) are required for OSM receptor activation. J Biol Chem 2018; 293:7017-7029. [PMID: 29511087 DOI: 10.1074/jbc.ra118.001920] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/16/2018] [Indexed: 01/11/2023] Open
Abstract
Oncostatin M (OSM) and leukemia inhibitory factor (LIF) are closely related members of the interleukin-6 (IL-6) cytokine family. Both cytokines share a common origin and structure, and both interact through a specific region, termed binding site III, to activate a dimeric receptor complex formed by glycoprotein 130 (gp130) and LIF receptor (LIFR) in humans. However, only OSM activates the OSM receptor (OSMR)-gp130 complex. The molecular features that enable OSM to specifically activate the OSMR are currently unknown. To define specific sequence motifs within OSM that are critical for initiating signaling via OSMR, here we generated chimeric OSM-LIF cytokines and performed alanine-scanning experiments. Replacement of the OSM AB loop within OSM's binding site III with that of LIF abrogated OSMR activation, measured as STAT3 phosphorylation at Tyr-705, but did not compromise LIFR activation. Correspondingly, substitution of the AB loop and D-helix in LIF with their OSM counterparts was sufficient for OSMR activation. The alanine-scanning experiments revealed that residues Tyr-34, Gln-38, Gly-39, and Leu-45 (in the AB loop) and Pro-153 (in the D-helix) had specific roles in activating OSMR but not LIFR signaling, whereas Leu-40 and Cys-49 (in the AB loop), and Phe-160 and Lys-163 (in the D-helix) were required for activation of both receptors. Because most of the key amino acid residues identified here are conserved between LIF and OSM, we concluded that comparatively minor differences in a few amino acid residues within binding site III account for the differential biological effects of OSM and LIF.
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Affiliation(s)
- Juan M Adrian-Segarra
- From the Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Natalie Schindler
- From the Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Praveen Gajawada
- From the Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Holger Lörchner
- From the Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Thomas Braun
- From the Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Jochen Pöling
- From the Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
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8
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The alpha helix 1 from the first conserved region of HIV1 gp120 is reconstructed in the short NQ21 peptide. Arch Biochem Biophys 2018; 638:66-75. [DOI: 10.1016/j.abb.2017.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 11/26/2017] [Accepted: 12/05/2017] [Indexed: 01/02/2023]
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9
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Khrustalev VV, Khrustaleva TA, Lelevich SV. Ethanol binding sites on proteins. J Mol Graph Model 2017; 78:187-194. [PMID: 29078103 DOI: 10.1016/j.jmgm.2017.10.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/15/2017] [Accepted: 10/17/2017] [Indexed: 01/19/2023]
Abstract
This study is on the analysis of ethanol binding sites on 3D structures of nonredundant proteins from the Protein Data Bank. The only one amino acid residue that is significantly overrepresented around ethanol molecules is Tyr. There are usually two or more Tyr residues in the same ethanol binding site, while residues of Thr, Asp and Gln are underrepresented around them. Residues of Ala and Pro are significantly underrepresented in ethanol binding surfaces. Several residues (Phe, Val, Pro, Ala, Arg, His, Ser, Asp) bind ethanol significantly more frequent if they are not included in beta strands. Residues of Ala, Ile and Arg preferably bind ethanol when they are included in an alpha helix. Ethanol molecules often make hydrogen bonds with oxygen and nitrogen atoms from the main chain of a protein. Because of this reason, the binding of ethanol may be associated with the decrease of the length of alpha helices and the disappearance of 3/10 helices. Obtained data should be useful for studies on new targets of the direct action of ethanol on enzymes, receptors, and transcription factors.
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Affiliation(s)
| | | | - Sergey Vladimirovich Lelevich
- Department of Clinical Laboratory Diagnostics, Allergology and Immunology, Grodno State Medical University, Gorkogo 80, Grodno, Belarus
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10
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Khrustalev VV, Khrustaleva TA, Szpotkowski K, Poboinev VV, Kakhanouskaya KY. The part of a long beta hairpin from the scrapie form of the human prion protein is reconstructed in the synthetic CC36 protein. Proteins 2016; 84:1462-79. [DOI: 10.1002/prot.25090] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 06/07/2016] [Accepted: 06/13/2016] [Indexed: 11/12/2022]
Affiliation(s)
| | - Tatyana Aleksandrovna Khrustaleva
- Laboratory of Cellular Technologies; Institute of Physiology of the National Academy of Sciences of Belarus; Academicheskaya, 28 Minsk Belarus
| | - Kamil Szpotkowski
- Department of Crystallography Center of Biocrystallographic Research; Institute of Bioorganic Chemistry, Polish Academy of Sciences; Z. Noskowskiego, 12/14 Poznan Poland
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11
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Magnesium and manganese binding sites on proteins have the same predominant motif of secondary structure. J Theor Biol 2016; 395:174-185. [DOI: 10.1016/j.jtbi.2016.02.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 12/30/2015] [Accepted: 02/04/2016] [Indexed: 01/19/2023]
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12
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The influence of flanking secondary structures on amino Acid content and typical lengths of 3/10 helices. INTERNATIONAL JOURNAL OF PROTEOMICS 2014; 2014:360230. [PMID: 25371821 PMCID: PMC4211214 DOI: 10.1155/2014/360230] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/19/2014] [Accepted: 09/27/2014] [Indexed: 11/25/2022]
Abstract
We used 3D structures of a highly redundant set of bacterial proteins encoded by genes of high, average, and low GC-content. Four types of connecting bridges—regions situated between any of two major elements of secondary structure (alpha helices and beta strands)—containing a pure random coil were compared with connecting bridges containing 3/10 helices. We included discovered trends in the original “VVTAK Connecting Bridges” algorithm, which is able to predict more probable conformation for a given connecting bridge. The highest number of significant differences in amino acid usage was found between 3/10 helices containing bridges connecting two beta strands (they have increased Phe, Tyr, Met, Ile, Leu, Val, and His usages but decreased usages of Asp, Asn, Gly, and Pro) and those without 3/10 helices. The typical (most common) length of 3/10 helices situated between two beta strands and between beta strand and alpha helix is equal to 5 amino acid residues. The preferred length of 3/10 helices situated between alpha helix and beta strand is equal to 3 residues. For 3/10 helices situated between two alpha helices, both lengths (3 and 5 amino acid residues) are typical.
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Khrustaleva TA, Khrustalev VV, Barkovsky EV, Kolodkina VL, Astapov AA. Structural and antigenic features of the synthetic SF23 peptide corresponding to the receptor binding fragment of diphtheria toxin. Mol Immunol 2014; 63:235-44. [PMID: 25062832 DOI: 10.1016/j.molimm.2014.07.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Revised: 07/01/2014] [Accepted: 07/05/2014] [Indexed: 10/25/2022]
Abstract
The SF23 peptide corresponding to the receptor binding fragment of diphtheria toxin (residues 508-530) has been synthesized. This fragment forming a protruding beta hairpin has been chosen because it is the less mutable B-cell epitope. Affine chromatography and ELISA show that antibodies from the sera of persons infected by toxigenic Corynebacterium diphtheriae and those immunized by diphtheria toxoid are able to bind the synthetic SF23 peptide. There are antibodies recognizing the SF23 peptide in the serum of horses hyperimmunized with diphtheria toxoid. Analysis of circular dichroism spectra show formation of beta hairpin by the peptide. Taken together, the results showed that the structure of the less mutable epitope of C. diphtheriae toxin was reproduced by the short SF23 peptide. Since antibodies against that epitope should block its interactions with cellular receptor (heparin-binding epidermal growth factor), the SF23 peptide can be considered as a promising candidate for synthetic vaccine development. Fluorescence quenching studies showed the existence of chloride and phosphate binding sites on the SF23 molecule. Phosphate containing adjuvants (aluminum hydroxyphosphate or aluminum hydroxyphosphate sulfate) are recommended to increase the SF23 immunogenic properties.
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Affiliation(s)
- Tatyana Aleksandrovna Khrustaleva
- Regulatory Proteins and Peptides Laboratory, Institute of Physiology of the National Academy of Sciences of Belarus, Academicheskaya 28, Minsk, Belarus
| | | | | | - Valentina Leonidovna Kolodkina
- Laboratory of Vaccine Preventable Diseases, Republican Research and Practical Centre for Epidemiology and Microbiology, Filimonova 23, Minsk, Belarus
| | - Anatoly Archipovich Astapov
- Department of Child Infectious Diseases, Belarusian State Medical University, Dzerzinskogo 83, Minsk, Belarus
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Secondary structure preferences of mn (2+) binding sites in bacterial proteins. Adv Bioinformatics 2014; 2014:501841. [PMID: 24778647 PMCID: PMC3977119 DOI: 10.1155/2014/501841] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 01/26/2014] [Accepted: 02/10/2014] [Indexed: 12/13/2022] Open
Abstract
3D structures of proteins with coordinated Mn2+ ions from bacteria with low, average, and high genomic GC-content have been analyzed (149 PDB files were used). Major Mn2+ binders are aspartic acid (6.82% of Asp residues), histidine (14.76% of His residues), and glutamic acid (3.51% of Glu residues). We found out that the motif of secondary structure “beta strand-major binder-random coil” is overrepresented around all the three major Mn2+ binders. That motif may be followed by either alpha helix or beta strand. Beta strands near Mn2+ binding residues should be stable because they are enriched by such beta formers as valine and isoleucine, as well as by specific combinations of hydrophobic and hydrophilic amino acid residues characteristic to beta sheet. In the group of proteins from GC-rich bacteria glutamic acid residues situated in alpha helices frequently coordinate Mn2+ ions, probably, because of the decrease of Lys usage under the influence of mutational GC-pressure. On the other hand, the percentage of Mn2+ sites with at least one amino acid in the “beta strand-major binder-random coil” motif of secondary structure (77.88%) does not depend on genomic GC-content.
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15
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Khrustalev VV, Khrustaleva TA, Barkovsky EV. Random coil structures in bacterial proteins. Relationships of their amino acid compositions to flanking structures and corresponding genic base compositions. Biochimie 2013; 95:1745-54. [DOI: 10.1016/j.biochi.2013.05.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 05/30/2013] [Indexed: 12/29/2022]
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