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Meganathan I, Sundarapandian A, Shanmugam G, Ayyadurai N. Three-dimensional tailor-made collagen-like proteins hydrogel for tissue engineering applications. BIOMATERIALS ADVANCES 2022; 139:212997. [PMID: 35882145 DOI: 10.1016/j.bioadv.2022.212997] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 05/23/2022] [Accepted: 06/19/2022] [Indexed: 06/15/2023]
Abstract
Despite the potential tunable properties of blank slate collagen-like proteins (CLP), an alternative to animal-originated collagen, assembling them into a stable 3D hydrogel to mimic extracellular matrix is a challenge. To address this constraint, the CLP (without hydroxyproline, CLPpro) and its variants encoding functional unnatural amino acids such as hydroxyproline (CLPhyp) and 3,4-dihydroxyphenylalanine (CLPdopa) were generated through genetic code engineering for 3D hydrogel development. The CLPhyp and CLPdopa were chosen to enhance the intermolecular hydrogen bond interaction through additional hydroxyl moiety and thereby facilitate the self-assembly into a fibrillar network of the hydrogel. Hydrogelation was induced through genipin as a cross-linker, enabling intermolecular cross-linking to form a hydrogel. Spectroscopic and rheological analyses confirmed that CLPpro and its variants maintained native triple-helical structure, which is necessary for its function, and viscoelastic nature of the hydrogels, respectively. Unlike CLPpro, the varients (CLPhyp and CLPdopa) increased pore size formation in the hydrogel scaffold, facilitating 3T3 fibroblast cell interactions. DSC analysis indicated that the stability of the hydrogels got increased upon the genetic incorporation of hydroxyproline (CLPhyp) and dopa (CLPdopa) in CLPpro. In addition, CLPdopa hydrogel was found to be relatively stable against collagenase enzyme compared to CLPpro and CLPhyp. It is the first report on 3D biocompatible hydrogel preparation by tailoring CLP sequence with non-natural amino acids. These next-generation tunable CLP hydrogels open a new venue to design synthetic protein-based biocompatible 3D biomaterials for tissue engineering applications.
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Affiliation(s)
- Ilamaran Meganathan
- Division of Biochemistry and Biotechnology, Council of Scientific and Industrial Research (CSIR) - Central Leather Research Institute, Chennai, Tamilnadu, India
| | - Ashokraj Sundarapandian
- Division of Biochemistry and Biotechnology, Council of Scientific and Industrial Research (CSIR) - Central Leather Research Institute, Chennai, Tamilnadu, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India
| | - Ganesh Shanmugam
- Division of Organic and Bioorganic Chemistry, Council of Scientific and Industrial Research (CSIR) - Central Leather Research Institute, Chennai, Tamilnadu, India.
| | - Niraikulam Ayyadurai
- Division of Biochemistry and Biotechnology, Council of Scientific and Industrial Research (CSIR) - Central Leather Research Institute, Chennai, Tamilnadu, India.
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Veettil SP, Gopinath A, Madhan B, Shanmugam G. A cyclodextrin-based macrocyclic oligosaccharide cavitand with a dual functionality limits the collagen fibrillogenesis: A possible carbohydrate-based therapeutic molecule for fibrotic diseases. Int J Biol Macromol 2022; 207:222-231. [PMID: 35259432 DOI: 10.1016/j.ijbiomac.2022.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 02/16/2022] [Accepted: 03/02/2022] [Indexed: 11/05/2022]
Abstract
β-Cyclodextrin (β-CD), a macrocyclic oligosaccharide cavitand, is a well-known candidate for drug delivery and formulation. In this study, we extended the application of β-CD using a β-cyclodextrin sulfate (β-CDS) as a possible therapeutic for fibrotic diseases caused by excess deposition of collagen fibrils. We have strategically chosen β-CDS, which mimics the natural existence of dermatan sulfate in the extracellular matrix, for limiting collagen fibrillation. The hydrophobic nature of the inner core β-CDS is expected to form an inclusion complex with hydrophobic side chain amino acids with the simultaneous action of forming an ionic bond through a negative charge on sulfate group with positively charged amino acids side chain in collagen. Various results suggested that such dual action not only limited the collagen fibrillation but also reduced the fibril size formed in the presence of β-CDS. The contemporary results thus indicate that β-CDS can be explored as a therapeutic molecule in fibrotic diseases.
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Affiliation(s)
- Sruthi Puthan Veettil
- Organic & Bioorganic Chemistry Laboratory, Council of Scientific and Industrial Research (CSIR) - Central Leather Research Institute (CLRI), Adyar, Chennai 600020, India
| | - Arun Gopinath
- CARE Division, CSIR-CLRI, Adyar, Chennai 600020, India
| | | | - Ganesh Shanmugam
- Organic & Bioorganic Chemistry Laboratory, Council of Scientific and Industrial Research (CSIR) - Central Leather Research Institute (CLRI), Adyar, Chennai 600020, India.
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Physicochemical characterization and self-assembly of human amniotic membrane and umbilical cord collagen: A comparative study. Int J Biol Macromol 2020; 165:2920-2933. [PMID: 33098903 DOI: 10.1016/j.ijbiomac.2020.10.107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 10/09/2020] [Accepted: 10/14/2020] [Indexed: 02/03/2023]
Abstract
The diverse application of collagen has created a need to discover renewable and economical sources with prevailing/improved physico-chemical properties. To address this scenario, the present study has extracted collagen from Human Amniotic Membrane (AM) and Umbilical cord, which are treated as medical waste and compared its physico-chemical properties. Collagen was extracted by pepsin solubilization using various salt concentrations (1 M, 2 M and 4 M). Umbilical Cord Collagen (UC) yield was 10% higher than Amniotic Membrane Collagen (AC). UC reported 58% higher sulphated glycosaminoglycan content than AC. Electrophoretic pattern of AC and UC in both disulphide bond reducing and non-reducing conditions showed bands corresponding to collagen type I, III, IV, V and XV. Collagen morphology was examined using SEM and the amino acid content was quantified by HPLC and LC-MS/MS. Triple helicity was confirmed by CD and FTIR spectra. Thermal transition temperature of AC and UC was found equivalent to animal collagen. Self-assembly, fibril morphology and spatial alignment was studied using AFM and DLS. Biocompatibility was analyzed using 3T3 fibroblast cells. In conclusion, UC with higher yield, presented with better physico-chemical, structural and biological properties than AC could serve as an efficient alternative to the existing animal collagen for diverse applications.
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Keiderling TA. Structure of Condensed Phase Peptides: Insights from Vibrational Circular Dichroism and Raman Optical Activity Techniques. Chem Rev 2020; 120:3381-3419. [DOI: 10.1021/acs.chemrev.9b00636] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Timothy A. Keiderling
- Department of Chemistry, University of Illinois at Chicago 845 West Taylor Street m/c 111, Chicago, Illinois 60607-7061, United States
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Instrumentation for Vibrational Circular Dichroism Spectroscopy: Method Comparison and Newer Developments. Molecules 2018; 23:molecules23092404. [PMID: 30235902 PMCID: PMC6225159 DOI: 10.3390/molecules23092404] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 08/25/2018] [Accepted: 09/07/2018] [Indexed: 01/10/2023] Open
Abstract
Vibrational circular dichroism (VCD) is a widely used standard method for determination of absolute stereochemistry, and somewhat less so for biomolecule characterization and following dynamic processes. Over the last few decades, different VCD instrument designs have developed for various purposes, and reliable commercial instrumentation is now available. This review will briefly survey historical and currently used instrument designs and describe some aspects of more recently reported developments. An important factor in applying VCD to conformational studies is theoretical modeling of spectra for various structures, techniques for which are briefly surveyed.
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Keiderling TA, Lakhani A. Mini review: Instrumentation for vibrational circular dichroism spectroscopy, still a role for dispersive instruments. Chirality 2018; 30:238-253. [PMID: 29293282 DOI: 10.1002/chir.22799] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 11/07/2017] [Accepted: 11/16/2017] [Indexed: 01/30/2023]
Abstract
Vibrational circular dichroism (VCD) has become a standard method for determination of absolute stereochemistry, particularly now that reliable commercial instrumentation has become available. These instruments use a now well-documented Fourier transform infrared-based approach to measure VCD that has virtually displaced initial dispersive infrared-based designs. Nonetheless, many papers have appeared reporting dispersive VCD data, especially for biopolymers. Instrumentation designed with these original methods, particularly after more recent updates optimizing performance in selected spectral regions, has been shown still to have advantages for specific applications. This article presents a mini-review of dispersive VCD instrument designs and includes sample spectra obtained for various biopolymer (particularly peptide) samples. Complementary reviews of Fourier transform-VCD designs are broadly available.
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Affiliation(s)
- Timothy A Keiderling
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Ahmed Lakhani
- Department of Biophysical Chemistry and Mathematics, Calumet College of St. Joseph, Whiting, Indiana, USA
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Kurouski D. Advances of Vibrational Circular Dichroism (VCD) in bioanalytical chemistry. A review. Anal Chim Acta 2017; 990:54-66. [PMID: 29029743 PMCID: PMC10389559 DOI: 10.1016/j.aca.2017.08.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/08/2017] [Accepted: 08/09/2017] [Indexed: 12/26/2022]
Abstract
Vibrational Circular Dichroism (VCD) is a unique and relatively new spectroscopic technique that is capable of determining an absolute configuration of chiral molecules. VCD can be also used to determine structure of large macromolecules. This review highlights the most recent advances of VCD in bioanalytical chemistry. It shows that VCD is capable of unraveling supramolecular organization of peptides, proteins, saccharides, glycerophospholipids, polypeptide microcrystals, as well as amyloid fibrils and DNA. This review also demonstrates how VCD can be utilized to explore molecule-molecule interactions that determine mechanisms of chiral separations in chromatography. It aims to attract attention of scientists from all different research areas demonstrating the strength and capability of this very powerful spectroscopic technique.
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Affiliation(s)
- Dmitry Kurouski
- Department Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA.
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Chen S, Tang L, Hao G, Weng W, Osako K, Tanaka M. Effects of α1/α2 ratios and drying temperatures on the properties of gelatin films prepared from tilapia (Tilapia zillii) skins. Food Hydrocoll 2016. [DOI: 10.1016/j.foodhyd.2015.07.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Vedhanayagam M, Mohan R, Nair BU, Sreeram KJ. Nanorod mediated collagen scaffolds as extra cellular matrix mimics. Biomed Mater 2015; 10:065010. [DOI: 10.1088/1748-6041/10/6/065010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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10
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Novotná P, Urbanová M. A Solid Phase Vibrational Circular Dichroism Study of Polypeptide-Surfactant Interaction. Chirality 2015; 27:965-72. [DOI: 10.1002/chir.22534] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 08/07/2015] [Accepted: 08/27/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Pavlína Novotná
- Department of Analytical Chemistry; University of Chemistry and Technology; Prague Czech Republic
| | - Marie Urbanová
- Department of Physics and Measurements; University of Chemistry and Technology; Prague Czech Republic
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Staicu T, Cîrcu V, Ioniţă G, Ghica C, Popa VT, Micutz M. Analysis of bimodal thermally-induced denaturation of type I collagen extracted from calfskin. RSC Adv 2015. [DOI: 10.1039/c5ra02708j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
DSC tracks of collagen in solution revealing a bimodal behaviour during its heat-induced denaturation.
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Affiliation(s)
- Teodora Staicu
- Department of Physical Chemistry
- University of Bucharest
- Bucharest 030018
- Romania
| | - Viorel Cîrcu
- Department of Inorganic Chemistry
- University of Bucharest
- Bucharest 020464
- Romania
| | - Gabriela Ioniţă
- Institute of Physical Chemistry “Ilie Murgulescu”
- Romanian Academy
- Bucharest 060021
- Romania
| | - Corneliu Ghica
- National Institute of Materials Physics
- Măgurele 077125
- Romania
| | - Vlad T. Popa
- Institute of Physical Chemistry “Ilie Murgulescu”
- Romanian Academy
- Bucharest 060021
- Romania
| | - Marin Micutz
- Department of Physical Chemistry
- University of Bucharest
- Bucharest 030018
- Romania
- Institute of Physical Chemistry “Ilie Murgulescu”
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Yang H, Wang H, Zhao Y, Wang H, Zhang H. Effect of heat treatment on the enzymatic stability of grass carp skin collagen and its ability to form fibrils in vitro. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2015; 95:329-336. [PMID: 24798991 DOI: 10.1002/jsfa.6724] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 04/28/2014] [Accepted: 04/28/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND The molecular configuration, molecular weight distribution and thermal transition enthalpy (ΔH) of grass carp skin (GCS) collagens after heat treatment under different conditions were measured using circular dichroism, gel filtration chromatography and differential scanning calorimetry (DSC). The enzymatic stability of collagen was evaluated using different enzymes, while the ability to form fibrils in vitro was assessed by morphological observation of collagen fibrils and turbidity testing. RESULTS The ΔH values, in-solution molecular aggregation and the stability to enzymatic hydrolysis of GCS collagen decreased irreversibly and progressively with the duration of heat treatment at 33 °C, which was the onset endothermic temperature obtained from the DSC curve. A strong positive linear correlation between the enzymatic sensitivity of collagen and the degree of thermal denaturation was found. A decrease in fibril diameter and D-periodicity length with denaturation could also be observed in the SEM and TEM images. CONCLUSION The onset endothermic temperature (To ) rather than the denaturation temperature (Td ) is the threshold temperature for configurational stability of GCS collagen in acidic solution, and the biological properties would obviously change if the collagen was heat treated at this temperature.
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Affiliation(s)
- Huan Yang
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei, China
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MORISAKU T, SOHARA Y, YUI H. Thermal Denaturation of Type I Collagen Fibrils Investigated with Vibrational Circular Dichroism Spectroscopy. KOBUNSHI RONBUNSHU 2015. [DOI: 10.1295/koron.2015-0033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Toshinori MORISAKU
- Department of Chemistry, Faculty of Science, Tokyo University of Science
| | - Yusuke SOHARA
- Department of Chemistry, Faculty of Science, Tokyo University of Science
| | - Hiroharu YUI
- Department of Chemistry, Faculty of Science, Tokyo University of Science
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Effect of aqueous ethanol on the triple helical structure of collagen. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2014; 43:643-52. [PMID: 25376150 DOI: 10.1007/s00249-014-0994-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/15/2014] [Accepted: 10/19/2014] [Indexed: 10/24/2022]
Abstract
Collagen, the most abundant protein in mammals, is widely used for making biomaterials. Recently, organic solvents have been used to fabricate collagen-based biomaterials for biological applications. It is therefore necessary to understand the behavior of collagen in the presence of organic solvents at low (≤50%, v/v) and high (≥90%, v/v) concentrations. This study was conducted to examine how collagen reacts when exposed to low and high concentrations of ethanol, one of the solvents used to make collagen-based biomaterials. Solubility testing indicated that collagen remains in solution at low concentrations (≤50%, v/v) of ethanol but precipitates (gel-like) thereafter, irrespective of the method of addition of ethanol (single shot or gradual addition); this behavior is different from that observed recently with acetonitrile. Collagen retains its triple helix in the presence of ethanol but becomes thermodynamically unstable, with substantially reduced melting temperature, with increasing concentration of ethanol. It was also found that the CD ellipticity at 222 nm, characteristic of the triple-helical structure, does not correlate with the thermal stability of collagen. Time-dependent experiments reveal that the collagen triple helix is kinetically stable in the presence of 0-40% (v/v) ethanol at low temperature (5 °C) but highly unstable in the presence of ethanol at elevated temperature (~34 °C). These results indicate that when ethanol is used to process collagen-based biomaterials, such factors as temperature and duration should be done taking into account, to prevent extensive damage to the triple-helical structure of collagen.
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Shanmugam G, Reddy SMM, Madhan B, Rao JR. Method of addition of acetonitrile influences the structure and stability of collagen. Process Biochem 2014. [DOI: 10.1016/j.procbio.2013.11.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Thirupathi Kumara Raja S, Thiruselvi T, Sailakshmi G, Ganesh S, Gnanamani A. Rejoining of cut wounds by engineered gelatin–keratin glue. Biochim Biophys Acta Gen Subj 2013; 1830:4030-9. [DOI: 10.1016/j.bbagen.2013.04.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/17/2013] [Accepted: 04/04/2013] [Indexed: 11/25/2022]
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17
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Shanmugam G, Reddy SMM, Natarajan V, Madhan B. 2,2,2-Trifluoroethanol disrupts the triple helical structure and self-association of type I collagen. Int J Biol Macromol 2013; 54:155-9. [DOI: 10.1016/j.ijbiomac.2012.12.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 11/16/2012] [Accepted: 12/07/2012] [Indexed: 12/01/2022]
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Liu Y, Liu L, Chen M, Zhang Q. Double thermal transitions of type I collagen in acidic solution. J Biomol Struct Dyn 2012; 31:862-73. [PMID: 22963008 DOI: 10.1080/07391102.2012.715042] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Contributed equally to this work. To further understand the origin of the double thermal transitions of collagen in acidic solution induced by heating, the denaturation of acidic soluble collagen was investigated by micro-differential scanning calorimeter (micro-DSC), circular dichroism (CD), dynamic laser light scattering (DLLS), transmission electron microscopy (TEM), and two-dimensional (2D) synchronous fluorescence spectrum. Micro-DSC experiments revealed that the collagen exhibited double thermal transitions, which were located within 31-37 °C (minor thermal transition, T(s) ∼ 33 °C) and 37-55 °C (major thermal transition, T(m) ∼ 40 °C), respectively. The CD spectra suggested that the thermal denaturation of collagen resulted in transition from polyproline II type structure to unordered structure. The DLLS results showed that there were mainly two kinds of collagen fibrillar aggregates with different sizes in acidic solution and the larger fibrillar aggregates (T(p2) = 40 °C) had better heat resistance than the smaller one (T(p1) = 33 °C). TEM revealed that the depolymerization of collagen fibrils occurred and the periodic cross-striations of collagen gradually disappeared with increasing temperature. The 2D fluorescence correlation spectra were also applied to investigate the thermal responses of tyrosine and phenylalanine residues at the molecular level. Finally, we could draw the conclusion that (1) the minor thermal transition was mainly due to the defibrillation of the smaller collagen fibrillar aggregates and the unfolding of a little part of triple helices; (2) the major thermal transition primarily arose from the defibrillation of the larger collagen fibrillar aggregates and the complete denaturation of the majority part of triple helices.
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Affiliation(s)
- Yan Liu
- Department of Biomaterials & Artificial Organs, Institute of Biomedical Engineering, Chinese Academy of Medical Science & Peking Union Medical College, Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, China
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Shanmugam G, Polavarapu PL, Láng E, Majer Z. Conformational analysis of amyloid precursor protein fragment containing amino acids 667–676, and the effect of d-Asp and iso-Asp substitution at Asp672 residue. J Struct Biol 2012; 177:621-9. [DOI: 10.1016/j.jsb.2012.01.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Revised: 01/10/2012] [Accepted: 01/26/2012] [Indexed: 11/28/2022]
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Polavarapu PL, Shanmugam G. Comparison of mid-infrared Fourier transform vibrational circular dichroism measurements with single and dual polarization modulations. Chirality 2011; 23:801-7. [DOI: 10.1002/chir.20999] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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Shanmugam G, Polavarapu PL. Isotope-assisted vibrational circular dichroism investigations of amyloid β peptide fragment, Aβ(16-22). J Struct Biol 2011; 176:212-9. [PMID: 21855637 DOI: 10.1016/j.jsb.2011.08.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 07/26/2011] [Accepted: 08/04/2011] [Indexed: 10/17/2022]
Abstract
Isotope-assisted vibrational circular dichroism (VCD) investigations have been used to probe the site specific local structure of an amyloid peptide for the first time. A seven residue peptide, NH(2)-KLVFFAE-COOH, which represents the Aβ(16-22) fragment of the Alzheimer's amyloid β peptide, was used for these investigations. (13)C labels were introduced separately at the carbonyl group of leucine (residue 17), alanine (residue 21) and also at both sites together. Since VCD spectra provide structure dependent signs, band shapes and frequencies, the isotope-assisted VCD spectroscopy revealed information on site specific secondary structure of the polypeptide. Isotope dilution VCD experiments provided a means to distinguish between parallel and anti-parallel nature of the β-sheet structure formed by the Aβ(16-22) fragment. The current results establish the usefulness of isotope-assisted VCD analysis in determining the site specific secondary structure of amyloid peptides.
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Affiliation(s)
- Ganesh Shanmugam
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
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Friebe VM, Mikulis B, Kole S, Ruffing CS, Sacks MS, Vyavahare NR. Neomycin enhances extracellular matrix stability of glutaraldehyde crosslinked bioprosthetic heart valves. J Biomed Mater Res B Appl Biomater 2011; 99:217-29. [DOI: 10.1002/jbm.b.31889] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 01/13/2011] [Accepted: 02/10/2011] [Indexed: 11/08/2022]
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