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Yang G, Chen X, Shi W, Chen N, Liu Y, Zhang B, Shao Z. Facile Preparation of a Photo-Cross-Linked Silk Fibroin-Poly Ionic Liquid Hydrogel with Antifreezing and Ion Conductive Properties. ACS APPLIED MATERIALS & INTERFACES 2024; 16:1543-1552. [PMID: 38163251 DOI: 10.1021/acsami.3c15712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
The silk fibroin (SF)/ionic liquid (IL) based hydrogel is a kind of remarkable substrate for flexible devices because of its subzero-temperature elasticity, electrical conductivity, and water retention, although the procedure of the gelation is considered complex and time-consuming. In this work, we introduced an approximate method for the development of novel photo-cross-linked SF/IL hydrogel, that is, SF-IMA/PIL hydrogel via the modification of silk fibroin chain with 2-isocyanatoethyl methacrylate (SF-IMA) in a certain ionic liquid with an unsaturated double bond. The chemical cross-linking between methacrylated SF and IL was triggered by UV light, while the physical cross-linking of the hydrogel was attributed to the β-sheet formation of SF in SF-IMA/IL mixed solution. In addition to being a UV-induced three-dimensional (3D) printable one, the SF-IMA/PIL hydrogel performed significant ionic conductivity between room temperature and -50 °C and water retention within a wide range of relative humidity, which were the featured advantages as the ionic liquid involved. Moreover, the static and dynamic mechanical tests demonstrated that the hydrogel reserved its great elasticity at -50 °C and displayed its stiffness transition temperatures between -100 and -70 °C.
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Affiliation(s)
- Gongwen Yang
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
| | - Xuyang Chen
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
| | - Wenjuan Shi
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
| | - Ni Chen
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
| | - Yi Liu
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
| | - Bo Zhang
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
| | - Zhengzhong Shao
- State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials and Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China
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2
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Wilson AL, Outeiral C, Dowd SE, Doig AJ, Popelier PLA, Waltho JP, Almond A. Deconvolution of conformational exchange from Raman spectra of aqueous RNA nucleosides. Commun Chem 2020; 3:56. [PMID: 36703475 PMCID: PMC9814580 DOI: 10.1038/s42004-020-0298-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 04/06/2020] [Indexed: 01/29/2023] Open
Abstract
Ribonucleic acids (RNAs) are key to the central dogma of molecular biology. While Raman spectroscopy holds great potential for studying RNA conformational dynamics, current computational Raman prediction and assignment methods are limited in terms of system size and inclusion of conformational exchange. Here, a framework is presented that predicts Raman spectra using mixtures of sub-spectra corresponding to major conformers calculated using classical and ab initio molecular dynamics. Experimental optimization allowed purines and pyrimidines to be characterized as predominantly syn and anti, respectively, and ribose into exchange between equivalent south and north populations. These measurements are in excellent agreement with Raman spectroscopy of ribonucleosides, and previous experimental and computational results. This framework provides a measure of ribonucleoside solution populations and conformational exchange in RNA subunits. It complements other experimental techniques and could be extended to other molecules, such as proteins and carbohydrates, enabling biological insights and providing a new analytical tool.
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Affiliation(s)
- Alex L. Wilson
- grid.5379.80000000121662407Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Science, Faculty of Science and Engineering, The University of Manchester, M1 7DN Manchester, UK
| | - Carlos Outeiral
- grid.5379.80000000121662407Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Science, Faculty of Science and Engineering, The University of Manchester, M1 7DN Manchester, UK
| | - Sarah E. Dowd
- grid.5379.80000000121662407Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Science, Faculty of Science and Engineering, The University of Manchester, M1 7DN Manchester, UK
| | - Andrew J. Doig
- grid.5379.80000000121662407Division of Neuroscience and Experimental Psychology, Michael Smith Building, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT Manchester, UK
| | - Paul L. A. Popelier
- grid.5379.80000000121662407Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Science, Faculty of Science and Engineering, The University of Manchester, M1 7DN Manchester, UK
| | - Jonathan P. Waltho
- grid.5379.80000000121662407Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Science, Faculty of Science and Engineering, The University of Manchester, M1 7DN Manchester, UK ,grid.11835.3e0000 0004 1936 9262Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, S10 2TN Sheffield, UK
| | - Andrew Almond
- grid.5379.80000000121662407Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Science, Faculty of Science and Engineering, The University of Manchester, M1 7DN Manchester, UK
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3
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Shashilov V, Xu M, Makarava N, Savtchenko R, Baskakov IV, Lednev IK. Dissecting structure of prion amyloid fibrils by hydrogen-deuterium exchange ultraviolet Raman spectroscopy. J Phys Chem B 2012; 116:7926-30. [PMID: 22681559 PMCID: PMC3490051 DOI: 10.1021/jp2122455] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The molecular mechanisms underlying structural diversity of amyloid fibrils or prion strains formed within the same primary structure is considered to be one of the most enigmatic questions in prion biology. We report here on the direct characterization of amyloid structures using a novel spectroscopic technique, hydrogen-deuterium exchange ultraviolet Raman spectroscopy. This method enables us to assess the structural differences within highly ordered cross-β-cores of two amyloid states produced within the same amino acid sequence of full-length mammalian prion protein. We found that while both amyloid states consisted of β-structures, their cross-β-cores exhibited hydrogen bonding of different strengths. Moreover, Raman spectroscopy revealed that both amyloid states displayed equally narrow crystalline-like bands, suggesting uniform structures of cross-β-cores within each state. Taken together, these data suggest that highly polymorphous fibrils can display highly uniform structures of their cross-β-core and belong to the same prion strain.
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Affiliation(s)
- Victor Shashilov
- Department of Chemistry, University at Albany, SUNY, 1400 Washington Ave., Albany, NY, USA 12222
| | - Ming Xu
- Department of Chemistry, University at Albany, SUNY, 1400 Washington Ave., Albany, NY, USA 12222
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA 21201
| | - Regina Savtchenko
- Center for Biomedical Engineering and Technology and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA 21201
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA 21201
| | - Igor K. Lednev
- Department of Chemistry, University at Albany, SUNY, 1400 Washington Ave., Albany, NY, USA 12222
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4
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Secondary structure of chorion proteins of the Lepidoptera Pericallia ricini and Ariadne merione by ATR FT-IR and micro-Raman spectroscopy. Int J Biol Macromol 2011; 49:317-22. [DOI: 10.1016/j.ijbiomac.2011.05.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2011] [Revised: 05/09/2011] [Accepted: 05/11/2011] [Indexed: 11/24/2022]
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5
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Sikirzhytski V, Virkler K, Lednev IK. Discriminant analysis of Raman spectra for body fluid identification for forensic purposes. SENSORS 2010; 10:2869-84. [PMID: 22319277 PMCID: PMC3274205 DOI: 10.3390/s100402869] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 03/13/2010] [Accepted: 03/23/2010] [Indexed: 11/16/2022]
Abstract
Detection and identification of blood, semen and saliva stains, the most common body fluids encountered at a crime scene, are very important aspects of forensic science today. This study targets the development of a nondestructive, confirmatory method for body fluid identification based on Raman spectroscopy coupled with advanced statistical analysis. Dry traces of blood, semen and saliva obtained from multiple donors were probed using a confocal Raman microscope with a 785-nm excitation wavelength under controlled laboratory conditions. Results demonstrated the capability of Raman spectroscopy to identify an unknown substance to be semen, blood or saliva with high confidence.
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Affiliation(s)
| | | | - Igor K. Lednev
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-518-591-8863
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6
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Oshima Y, Sato H, Zaghloul A, Foulks GN, Yappert MC, Borchman D. Characterization of Human Meibum Lipid using Raman Spectroscopy. Curr Eye Res 2009; 34:824-35. [DOI: 10.3109/02713680903122029] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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7
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Preliminary investigations on the effects of ageing and cooking on the Raman spectra of porcine longissimus dorsi. Meat Sci 2008; 80:1205-11. [PMID: 22063858 DOI: 10.1016/j.meatsci.2008.05.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 05/13/2008] [Accepted: 05/15/2008] [Indexed: 11/22/2022]
Abstract
The influence of ageing and cooking on the Raman spectrum of porcine longissimus dorsi was investigated. The rich information contained in the Raman spectrum was highlighted, with numerous changes attributed to changes in the environment and conformations of the myofibrillar proteins. Predictions equations for shear force and cooking loss were developed from the Raman spectra of both raw and cooked pork. Good correlations and standard errors of prediction were obtained for both WB shear force and cooking loss, with the raw and the cooked samples showing almost identical results R(2)=0.77, root mean standard error of prediction (RMSEP)% of mean=12% for shear force; R(2)=0.71, RMSEP% of mean=10% for cooking loss. The Raman spectra were also able to predict the extent of cooking that occurred within the pork (R(2)(val)=0.94, RMSEP% of range=5.5%). Raman spectroscopy has considerable potential as a method for non-destructive and rapid determination of pork quality parameters such as tenderness. Raman spectroscopy may provide a means of determining changes during cooking and the extent to which foods have been cooked.
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8
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Ma L, Ahmed Z, Mikhonin AV, Asher SA. UV resonance Raman measurements of poly-L-lysine's conformational energy landscapes: dependence on perchlorate concentration and temperature. J Phys Chem B 2007; 111:7675-80. [PMID: 17567063 DOI: 10.1021/jp0703758] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
UV resonance Raman spectroscopy has been used to determine the conformational energy landscape of poly-L-lysine (PLL) in the presence of NaClO4 as a function of temperature. At 1 degree C, in the presence of 0.83 M NaClO4, PLL shows an approximately 86% alpha-helix-like content, which contains alpha-helix and pi-bulge/helix conformations. The high alpha-helix-like content of PLL occurs because of charge screening due to strong ion-pair formation between ClO4- and the lysine side chain -NH3+. As the temperature increases from 1 to 60 degrees C, the alpha-helix and pi-bulge/helix conformations melt into extended conformations (PPII and 2.51-helix). We calculate the Psi Ramachandran angle distribution of the PLL peptide bonds from the UV Raman spectra which allows us to calculate the PLL (un)folding energy landscapes along the Psi reaction coordinate. We observe a basin in the Psi angle conformational space associated with alpha-helix and pi-bulge/helix conformations and another basin for the extended PPII and 2.51-helical conformations.
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Affiliation(s)
- Lu Ma
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
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9
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Iconomidou VA, Georgaka ME, Chryssikos GD, Gionis V, Megalofonou P, Hamodrakas SJ. Dogfish egg case structural studies by ATR FT-IR and FT-Raman spectroscopy. Int J Biol Macromol 2007; 41:102-8. [PMID: 17292464 DOI: 10.1016/j.ijbiomac.2007.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Revised: 01/09/2007] [Accepted: 01/09/2007] [Indexed: 11/27/2022]
Abstract
The dogfish egg case is a composite structure that combines mechanical tensile strength, toughness and elasticity with high permeability to small molecules and ions. Presumably, it provides both a protective and a filtering role for the egg/embryo contained within it. In this work, we performed structural studies of the Galeus melastomus egg case at two different stages of the hardening process, utilizing ATR FT-IR and FT-Raman spectroscopy. Based on these data we deduce that: (a) The G. melastomus egg case, in close analogy to that of the related species Scyliorhinus cunicula, is a complex, composite structure which consists mainly of an analogue of collagen IV. This network forming protein appears to have common secondary structural characteristics in the entire egg case. (b) The outermost layer of the non-sclerotized egg case is especially rich in tyrosine, while the innermost layer is rich in polysaccharides, presumably glycosaminoglycans, and lipids. These differences are diminished upon hardening. (c) Disulfide bonds do not appear to play a significant role in cross-linking. However, cross-links involving tyrosine residues appear to sclerotize the egg case. It is proposed that the intensity of the Raman band at ca. 1615 cm(-1), which is due to ring stretching vibrations of Tyr, might be a useful indicator of the sclerotization status of a certain proteinaceous tissue, when tyrosines are involved in sclerotization mechanisms.
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Affiliation(s)
- Vassiliki A Iconomidou
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, Panepistimiopolis, Athens 157 01, Greece.
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10
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Ashton L, Barron LD, Hecht L, Hyde J, Blanch EW. Two-dimensional Raman and Raman optical activity correlation analysis of the alpha-helix-to-disordered transition in poly(L-glutamic acid). Analyst 2007; 132:468-79. [PMID: 17471394 DOI: 10.1039/b700421d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rich and complex Raman scattering and Raman optical activity (ROA) spectra have been measured monitoring the pH induced alpha-helix-to-disordered conformational transition in poly(L-glutamic acid). Two-dimensional (2D) correlation techniques have been applied to facilitate a comprehensive analysis of these two complementary spectral sets. Synchronous contour plots have identified band assignments of alpha-helical and disordered conformations, and have revealed bands characteristic of changes in the protonation state of the polypeptide. Asynchronous plots, on the other hand, have probed the relative sequential orders of intensity changes indicating a decrease in intensity of alpha-helical bands in the backbone skeletal stretch region, followed by a subsequent decrease in intensity in the extended amide III and amide I regions, underlying the appearance of disordered structure, including poly(L-proline) II (PPII) helix. The application of a 2D correlation 'moving' window has also disclosed two distinct phases during helix unfolding in the alpha-helix-to-disordered transition, occurring at approximately pH 4.9 and approximately pH 5.2, possibly a result of the difference in helical stability between the end and central regions of the alpha-helix. This paper demonstrates the potential value of combining 2D Raman, 2D ROA and moving window correlation techniques for the detailed investigation of complex and subtle changes of secondary structure during the unfolding mechanisms of polypeptides and proteins.
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Affiliation(s)
- Lorna Ashton
- Manchester Interdisciplinary Biocentre, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester, UKM1 7DN
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11
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The effects of freeze-drying and storage on the FT-Raman spectra of Atlantic mackerel (Scomber scombrus) and horse mackerel (Trachurus trachurus). Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.06.065] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Shih S, Weng YM, Chen S, Huang SL, Huang CH, Chen W. FT-Raman spectroscopic investigation of lens proteins of tilapia treated with dietary vitamin E. Arch Biochem Biophys 2004; 420:79-86. [PMID: 14622977 DOI: 10.1016/j.abb.2003.09.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
FT-Raman spectroscopy was employed to explore the structural changes of lens proteins in Tilapia lenses affected by dietary vitamin E supplementation. The microenvironment of major lens constituents including thiol compounds, tyrosine, and tryptophan exhibited significant change upon vitamin E treatment, while the protein secondary structure was unaltered and remained as an antiparallel beta-pleated sheet. These structures in the cortex were more susceptible to vitamin E treatment than in the nucleus. Protein sulfhydryls in the cortex were predominantly in the reduced form, while in the nucleus both the oxidized and reduced forms coexisted as evidenced by the vibrational mode of SH (2580 cm(-1)) and SS (507 cm(-1)), respectively. Both tyrosine and tryptophan were more accessible to water or more exposed in the cortex than in the nucleus. The symmetrically inverse response of vitamin E, between Raman intensity of 1090 cm(-1) and the glutathione level, was consistent with a close relationship of GSH and vitamin E in defending the lens from external insults.
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Affiliation(s)
- Shoeher Shih
- Department of Food Science, National Chiayi University, Chiayi, Taiwan
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13
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Iconomidou VA, Chryssikos GD, Gionis V, Hoenger A, Hamodrakas SJ. FT-Raman spectroscopy as diagnostic tool of Congo red binding to amyloids. Biopolymers 2003; 72:185-92. [PMID: 12722114 DOI: 10.1002/bip.10344] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chorion is the major component of silkmoth eggshell. More than 95% of its dry mass consists of the A and B families of low molecular weight structural proteins, which have remarkable mechanical and chemical properties protecting the oocyte and developing embryo from environmental hazards. We present data from FT-Raman spectroscopy of silkmoth chorion and amyloid-like fibrils formed from peptide analogues of chorion proteins, both unstained and stained by Congo red. The results show that FT-Raman spectroscopy is not a straightforward diagnostic tool for the specific interactions of Congo red with amyloids: a dilute aqueous solution of the Congo red dye at pH 5.5 and a thin solid film of the dye cast from this solution exhibit the same "diagnostic" Raman shifts relative to the neat Congo red dry powder as do amyloid fibrils formed from peptide analogues of chorion proteins stained by Congo red. An important consequence of this finding is that these shifts of the Raman active modes of Congo red are probably due to the formation of supramolecular dye aggregates in the presence of water. Therefore, this is not an appropriate diagnostic test for Congo red binding to amyloids.
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Affiliation(s)
- Vassiliki A Iconomidou
- Department of Cell Biology and Biophysics, University of Athens, Panepistimiopolis, Athens 157 01, Greece
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14
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Cotton TM, Van Duyne RP. Resonance Raman scattering from Rhodopseudomonas sphaeroides
reaction centers absorbed on a silver electrode. FEBS Lett 2001. [DOI: 10.1016/0014-5793(82)81015-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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15
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Iconomidou VA, Chryssikos GD, Gionis V, Willis JH, Hamodrakas SJ. "Soft"-cuticle protein secondary structure as revealed by FT-Raman, ATR FT-IR and CD spectroscopy. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2001; 31:877-885. [PMID: 11439247 DOI: 10.1016/s0965-1748(01)00033-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The nature of the interaction of insect cuticular proteins and chitin is unknown even though about half of the cuticular proteins sequenced thus far share a consensus region that has been predicted to be the site of chitin binding. We previously predicted the preponderance of a beta-pleated sheet in the consensus region and proposed its responsibility for the formation of helicoidal cuticle (Iconomidou et al., Insect Biochem. Mol. Biol. 29 (1999) 285). In this study, we examined experimentally the secondary structure of intact and guanidine hydrochloride extracted cuticle and the cuticular protein extract. The studied cuticle came from the larval dorsal abdomen of the lepidopteran Hyalophora cecropia, a classical example of "soft" cuticle. Analysis with FT-Raman, ATR FT-IR and CD spectroscopy indicates that antiparallel beta-pleated sheet is the predominant molecular conformation of "soft-cuticle" proteins both in situ in the cuticle and following extraction. It seems that this conformation dictates the modes of chitin-protein interaction in cuticle, in agreement with earlier proposals (Atkins, J. Biosci. 8 (1985) 375).
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Affiliation(s)
- V A Iconomidou
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, 157 01, Athens, Greece
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16
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Iconomidou VA, Chryssikos DG, Gionis V, Pavlidis MA, Paipetis A, Hamodrakas SJ. Secondary structure of chorion proteins of the teleostean fish Dentex dentex by ATR FT-IR and FT-Raman spectroscopy. J Struct Biol 2000; 132:112-22. [PMID: 11162733 DOI: 10.1006/jsbi.2000.4307] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
FT-Raman spectroscopy and ATR-IR spectroscopy were applied to study the secondary structure of the eggshell (chorion) proteins of the teleostean fish Dentex dentex. Raman and IR spectra clearly indicate an abundance of antiparallel beta-pleated sheet conformation in chorion proteins. This finding is further supported by analysis of the vibrational data by regression techniques and deconvolution procedures. Thus, the common morphological characteristics of D. dentex, Salmo gairdneri, and other teleostean fish chorions may be explained on the basis of common secondary structure features of their constituent proteins. A detailed understanding of the interactions that dictate the self-assembly of fish chorion proteins to form the fish eggshell awaits determination of amino acid sequences.
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Affiliation(s)
- V A Iconomidou
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, Athens 157 01, Greece
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17
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Barron LD, Hecht L, Blanch EW, Bell AF. Solution structure and dynamics of biomolecules from Raman optical activity. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2000; 73:1-49. [PMID: 10781828 DOI: 10.1016/s0079-6107(99)00017-6] [Citation(s) in RCA: 164] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Raman optical activity (ROA) measures vibrational optical activity by means of a small difference in the intensity of Raman scattering from chiral molecules in right and left circularly polarized incident laser light. The ROA spectra of a wide range of biomolecules in aqueous solution can now be measured routinely. Because of its sensitivity to the chiral elements of biomolecular structure, ROA provides new information about solution structure and dynamics complementary to that supplied by conventional spectroscopic techniques. This article provides a brief introduction to the theory and practice of ROA spectroscopy followed by a review of recent ROA results on polypeptides, proteins, carbohydrates, nucleic acids and viruses which illustrate how new insight into current problems of structure, folding and function may be obtained from ROA studies.
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Affiliation(s)
- L D Barron
- Chemistry Department, University of Glasgow, Glasgow, UK.
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18
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Benaki DC, Aggeli A, Chryssikos GD, Yiannopoulos YD, Kamitsos EI, Brumley E, Case ST, Boden N, Hamodrakas SJ. Laser-Raman and FT-IR spectroscopic studies of peptide-analogues of silkmoth chorion protein segments. Int J Biol Macromol 1998; 23:49-59. [PMID: 9644596 DOI: 10.1016/s0141-8130(98)00032-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Silkmoth chorion, the proteinaceous major component of the eggshell, with extraordinary mechanical and physiological properties, consists of a complex set of proteins, which have a tripartite structure: a central, evolutionarily conserved, domain and two more variable 'arms'. Peptide-analogues of silkmoth chorion protein central domain segments have been synthesized. Laser-Raman and infrared spectroscopic studies suggest the preponderance of antiparallel beta-pleated sheet structure for these peptides, both in solution and in the solid state.
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Affiliation(s)
- D C Benaki
- Department of Biology, University of Athens, Greece
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19
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Silva ND, Prendergast FG. Tryptophan dynamics of the FK506 binding protein: time-resolved fluorescence and simulations. Biophys J 1996; 70:1122-37. [PMID: 8785272 PMCID: PMC1225042 DOI: 10.1016/s0006-3495(96)79706-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The FK506-binding protein (FKBP12) is important in the immunosuppressant action of FK506 and rapamycin. We have investigated Trp side chain dynamics in FKBP12, with and without a bound immunosuppressant, by measuring the Trp time-resolved fluorescence anisotropy decay r(t). The r(t) for W59 in aqueous uncomplexed FKBP12 at 20 degrees C is well described by a single exponential with a recovered initial anisotropy, r(eff)o, of 0.192 and an overall rotational correlation time for the protein, phi p, of 4.7 ns; r(eff)o = 0.214 and phi p = 4.2 ns for the FKBP12/FK506 complex. Using an expression for the order parameter squared, namely S2 = r(eff)o/rTo, where rTo is the vitrified steady-state excitation anisotropy, we recovered an S2 of 0.75 for W59 fluorescence in uncomplexed FKBP12 and S2 approximately equal to 1 in the FKBP12/FK506 complex. Results obtained for the FKBP12/rapamycin complex are similar to those found for the FKBP12/FK506 complex. Minimum perturbation mapping simulations were performed on the free and complexed forms of FKBP12 and the results were generally in agreement with the experimental data.
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Affiliation(s)
- N D Silva
- Department of Pharmacology, Mayo Foundation, Rochester, Minnesota 55905, USA
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20
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Wilson G, Hecht L, Barron LD. Vibrational Raman optical activity of α-helical and unordered poly(L-lysine). ACTA ACUST UNITED AC 1996. [DOI: 10.1039/ft9969201503] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Orfanidou CC, Hamodrakas SJ, Chryssikos GD, Kamitsos EI, Wellman SE, Case ST. Spectroscopic studies of Manduca sexta and Sesamia nonagrioides chorion protein structure. Int J Biol Macromol 1995; 17:93-8. [PMID: 7547721 DOI: 10.1016/0141-8130(95)93523-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The secondary structure of Manduca sexta and Sesamia nonagrioides chorion proteins has been studied in intact chorions using laser-Raman and Fourier transform infra-red (FTIR) spectroscopy and in a solution containing extracted and reassembled chorion proteins using circular dichroism (CD) spectroscopy. Laser-Raman and IR spectra suggest the predominance of antiparallel beta-pleated sheet structure in intact chorion proteins of both Lepidoptera species. The bands at 1673, 1674 cm-1 (amide I) and 1234-1238 cm-1 (amide III) in the laser-Raman spectra can best be interpreted as resulting from abundant antiparallel beta-pleated sheet structure. Analysis of the amide I band suggests that chorion proteins consist of 60-70% antiparallel beta-pleated sheet and 30-40% beta-turns. Supporting evidence for the prevalence of antiparallel beta-pleated sheet in chorion proteins was supplied using FTIR spectroscopy by the observation of a very intense absorption band at 1635 cm-1 (amide I) and of a weak band at 1530, 1525 cm-1 (amide II) from chorions of both species. Surprisingly, analysis of the CD spectra of extracted and reassembled chorion proteins suggests that, in solution, they retain a regular secondary structure most probably dominated by beta-pleated sheet. We therefore suggest that the prominent regular beta-sheet structure of chorion proteins may exist in solution and dictate the aggregation and polymerization process in vivo.
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Affiliation(s)
- C C Orfanidou
- Department of Biochemistry, Cell and Molecular Biology and Genetics, University of Athens, Greece
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22
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Affiliation(s)
- W L Peticolas
- Department of Chemistry, University of Oregon, Eugene 97403, USA
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23
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Abstract
I will not attempt to summarize this chapter, which is already a summary. I merely wish to point out that experimental and theoretical evidence to date clearly suggests that antiparallel beta-pleated sheet dictates self-assembly in helicoidal proteinaceous eggshells. Molecular details of this process have started to become clear after the development of the specific, most probably correct, protein structural models in the case of the silkmoths, where amino acid information is available and with the help of several experimental techniques. However, for people seeking universal mechanisms the picture should still be far from complete. Several analogous systems should be studied before providing final answers.
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Affiliation(s)
- S J Hamodrakas
- Department of Biochemistry, Cell and Molecular Biology, and Genetics, University of Athens, Panepistimiopolis, Greece
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24
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McKenzie HA, White FH. Lysozyme and alpha-lactalbumin: structure, function, and interrelationships. ADVANCES IN PROTEIN CHEMISTRY 1991; 41:173-315. [PMID: 2069076 DOI: 10.1016/s0065-3233(08)60198-9] [Citation(s) in RCA: 177] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- H A McKenzie
- Department of Chemistry, University College, University of New South Wales, Australian Defence Force Academy, Canberra, ACT, Australia
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25
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Sessions RB, Dauber-Osguthorpe P, Osguthorpe DJ. Filtering molecular dynamics trajectories to reveal low-frequency collective motions: phospholipase A2. J Mol Biol 1989; 210:617-33. [PMID: 2614836 DOI: 10.1016/0022-2836(89)90136-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A novel method for analysing molecular dynamics trajectories has been developed, which filters out high frequencies using digital signal processing techniques and facilitates focusing on the low-frequency collective motions of proteins. These motions involve low energy slow motions, which lead to important biological phenomena such as domain closure and allosteric effects in enzymes. The filtering method treats each of the atomic trajectories obtained from the molecular dynamics simulation as a "signal". The trajectories of each of the atoms in the system (or any subset of interest) are Fourier transformed to the frequency domain, a filtering function is applied and then an inverse transformation back to the time domain yields the filtered trajectory. The filtering method has been used to study the dynamics of the enzyme phospholipase A2. In the filtered trajectory, all the high frequency bond and valence angle vibrations were eliminated, leaving only low-frequency motion, mainly fluctuations in torsions and conformational transitions. Analysis of this trajectory revealed interesting motions of the protein, including concerted movements of helices, and changes in shape of the active site cavity. Unlike normal mode analysis, which has been used to study the motion of proteins, this method does not require converged minimizations or diagonalization of a matrix of second derivatives. In addition, anharmonicity, multiple minima and conformational transitions are treated explicitly. Thus, the filtering method avoids most of the approximations implicit in other investigations of the dynamic behaviour of large systems.
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Affiliation(s)
- R B Sessions
- Molecular Graphics Unit, University of Bath, Claverton Down, U.K
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26
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Yu NT, DeNagel DC, Slingsby C. Raman spectroscopy of calf lens gamma-II crystallin: direct evidence for the formation of mixed disulfide bonds with 2-mercaptoethanol and glutathione. Exp Eye Res 1989; 48:399-410. [PMID: 2924822 DOI: 10.1016/s0014-4835(89)80008-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This study presents Raman spectra of calf lens gamma-II crystallin and its reaction products with reduced glutathione, 2-mercaptoethanol and p-hydroxymercuribenzoate. The absence of a disulfide vibration in gamma-III crystallin (both in aqueous solution and in lyophilized state) indicates that the seven thiol groups in this protein are resistant to air oxidation, and are capable of maintaining their reduced state in the absence of added reducing agents during isolation. However, treatment of the protein with low molecular weight thiols such as glutathione and 2-mercaptoethanol results in mixed disulfide bonds. We have detected, for the first time, the S--S bond stretching vibration from the mixed disulfides at 510 cm-1, which is very similar to the 508 cm-1 reported for the inter/intramolecular disulfide bonds in intact mouse lenses (Yu, N.-T., DeNagel, D.C., Pruett, P.L. and Kuck, J.F.R., Jr. (1985). Proc. Natl. Acad. Sci. U.S.A., 82, 7965-8). Upon titration with five equivalents of p-hydroxymercuribenzoate, a strong Raman line was detected at 345 cm-1, which is tentatively attributed to the Hg--S stretching vibration of the mercaptide complex. The S--H vibration region (2500-2700 cm-1) exhibits two resolved peaks at 2562 and 2580 cm-1 with an intensity ratio of 2:5. Both reactive surface thiol groups and buried cysteines give rise to the S--H vibration at 2580 cm-1.
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Affiliation(s)
- N T Yu
- School of Chemistry, Georgia Institute of Technology, Atlanta 30332
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27
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Kruse-Jarres JD. Physicochemical determinations of glucose in vivo. JOURNAL OF CLINICAL CHEMISTRY AND CLINICAL BIOCHEMISTRY. ZEITSCHRIFT FUR KLINISCHE CHEMIE UND KLINISCHE BIOCHEMIE 1988; 26:201-8. [PMID: 2841401 DOI: 10.1515/cclm.1988.26.4.201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Conventional methods for the determination of blood glucose are not suitable for application in vivo. It is therefore necessary to seek other methods for monitoring blood glucose as a controlled variable of pancreatic hormonal regulation. Physical methods are preferable to conventional chemical methods, because the chosen methods should not consume or chemically modify glucose. There are two main types of physical chemical methods, which can be considered for this purpose: 1) invasive methods, in which measurements are made directly in the blood stream, and 2) non-invasive methods. The first type is represented by electrochemical catalysts and fuel cells, the latter by spectroscopic procedures (mainly NMR- and IR-spectroscopy).
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Affiliation(s)
- J D Kruse-Jarres
- Institut für Klinische Chemie und Laboratoriumsmedizin, Katharinenhospital, Stuttgart
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28
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Zheng S, Tu AT, Renugopalakrishnan V, Strawich E, Glimcher MJ. A mixed beta-turn and beta-sheet structure for bovine tooth enamel amelogenin: Raman spectroscopic evidence. Biopolymers 1987; 26:1809-13. [PMID: 3663856 DOI: 10.1002/bip.360261012] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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29
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Beswick HT, Harding JJ. Conformational changes induced in lens alpha- and gamma-crystallins by modification with glucose 6-phosphate. Implications for cataract. Biochem J 1987; 246:761-9. [PMID: 3689329 PMCID: PMC1148342 DOI: 10.1042/bj2460761] [Citation(s) in RCA: 98] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
There is good evidence that the non-enzymic chemical modification of proteins plays a role in the aetiology of cataract and diabetic sequelae. This paper presents new evidence that glycosylation of two major lens structural crystallins, alpha- and gamma-crystallins, by glucose 6-phosphate (G6P) induces conformational changes in the proteins. In addition the surface charge on the molecules is altered. These changes would affect protein-protein and protein-water interactions within the lens and could lead to disruption of the short-range order of the lens proteins which is essential for lens transparency. Conformational changes to lens proteins are known to occur in human cataractous lenses but their cause in vivo is not established. Cumulative chemical modification of proteins, over a period of decades, is a strong candidate as a causal agent.
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Affiliation(s)
- H T Beswick
- Nuffield Laboratory of Ophthalmology, University of Oxford, U.K
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30
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Hamodrakas SJ, Kamitsos EI, Papadopoulou PG. Laser-Raman and infrared spectroscopic studies of protein conformation in the eggshell of the fish Salmo gairdneri. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 913:163-9. [PMID: 3593737 DOI: 10.1016/0167-4838(87)90326-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Laser-Raman and infrared spectroscopic studies reveal abundant beta-pleated sheet conformation in the eggshell proteins of the fish Salmo gairdneri. This secondary structure is the underlying molecular conformation, dictating the formation of the helicoidal architecture of the eggshell. Disulphide bonds crosslink the eggshell proteins of the fertilized eggs and are apparently found in g-g-g (gauche-gauche-gauche), g-g-t (gauche-gauche-trans) and t-g-t (trans-gauche-trans) conformation. There is no evidence for the existence of free sulphydryls. The tyrosines appear to act as hydrogen-bond acceptors, whereas the aromatic residues phenylalanine and tryptophan are also eggshell protein constituents.
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31
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32
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Diem M, Bhatnagar RS, Druyan ME, Renugopalakrishnan V. Solution-phase Raman-spectroscopic studies on synthetic collagen analogs: prolyl-prolyl-glycine and (prolyl-prolyl-glycine). Biopolymers 1984; 23:2955-61. [PMID: 6525410 DOI: 10.1002/bip.360231218] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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33
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Hamodrakas S, Kamitsos E, Papanikolaou A. Laser-Raman spectroscopic studies of the eggshell (chorion) of Bombyx mori. Int J Biol Macromol 1984. [DOI: 10.1016/0141-8130(84)90019-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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34
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Bennett WS, Huber R. Structural and functional aspects of domain motions in proteins. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1984; 15:291-384. [PMID: 6325088 DOI: 10.3109/10409238409117796] [Citation(s) in RCA: 206] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Three distinct categories of large-scale flexibility in proteins have been documented by single-crystal X-ray diffraction studies: the relatively free movement of essentially rigid globular domains that are connected by a flexible segment of polypeptide, the reorientation of essentially rigid domains among a few distinct conformations, and the concerted transition of a contiguous region of the surface of a protein from a disordered state to an ordered state. In a number of examples, well-defined functions can be assigned to these large-scale structural changes. The occurrence of such motions in proteins of known structure is reviewed, and the best-studied examples are discussed in detail to allow a critical evaluation of the methods used to identify and study these motions.
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35
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Nielsen OF, Lund PA, Nielsen LS, Praestgaard E. Aspects of low frequency vibrations (20-350 cm-1) from Watson-Crick base pairing in an aqueous solution of tRNA. Biochem Biophys Res Commun 1983; 111:120-6. [PMID: 6187341 DOI: 10.1016/s0006-291x(83)80125-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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36
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Hamodrakas SJ, Asher SA, Mazur GD, Regier JC, Kafatos FC. Laser Raman studies of protein conformation in the silkmoth chorion. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 703:216-22. [PMID: 7082682 DOI: 10.1016/0167-4838(82)90051-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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37
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3. Raman Spectroscopy. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/s0076-695x(08)60152-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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38
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Tu AT, Fox J, Pool WR, Bieber AL. Comparison of conformations of Mojave toxin subunits and reconstituted toxin. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/0305-0491(82)90059-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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39
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40
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Kuck JF, Yu NT, Askren CC. Total sulfhydryl by raman spectroscopy in the intact lens of several species: variations in the nucleus and along the optical axis during aging. Exp Eye Res 1982; 34:23-37. [PMID: 7056309 DOI: 10.1016/0014-4835(82)90005-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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41
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Laser Raman characterization of conformational changes in sarcoplasmic reticulum induced by temperature, Ca2+, and Mg2+. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(18)43288-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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42
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Ishizaki H, Balaram P, Nagaraj R, Venkatachalapathi YV, Tu AT. Determination of beta-turn conformation by laser Raman spectroscopy. Biophys J 1981; 36:509-17. [PMID: 7326322 PMCID: PMC1327643 DOI: 10.1016/s0006-3495(81)84749-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
To correlate the Raman frequencies of the amide I and III bands to beta-turn structures, three peptides shown to contain beta-turn structure by x-ray diffraction and NMR were examined. The compounds examined were tertiary (formula: see text). The amide I band of these compounds is seen at 1,668, 1,665, and 1,677 cm-1, and the amide III band appears at 1,267, 1,265, and 1,286 cm-1, respectively. Thus, it is concluded that the amide I band for type III beta-turn structure appears in the range between 1,665 and 1,677 cm-1 and the amide III band between 1,265 and 1,286 cm-1.
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43
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Asher SA, Schuster TM. Differences in iron-fluoride bonding between the isolated subunits of human methemoglobin fluoride and sperm whale metmyoglobin fluoride as measured by resonance Raman spectroscopy. Biochemistry 1981; 20:1866-73. [PMID: 7225362 DOI: 10.1021/bi00510a023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The heme geometries of the isolated alpha and beta subunits of human methemoglobin fluoride (HbIIIF) and sperm whale metmyoglobin fluoride (MbIIIF) have been examined by exciting their Raman spectra within their ca. 6000-A charge-transfer absorption bands. The Fe-F stretching vibration at 471 cm-1 in the beta subunits shifts to 466 cm-1 in the alpha subunits and to 461 cm-1 in MbIIIF. The Fe-F bond is estimated to elongate by 0.02 A in the alpha subunits and 0.03 AZ in MbIIIF compared with that in the beta subunits. This bond elongation is interpreted to result from an increased iron displacement toward the proximal histidine side of the heme in the series MbIIIF greater than alpha greater than beta. A comparison of the isolated subunit spectra with that of tetrameric HbIIIF indicates little change occurs in isolated subunit heme geometry upon association into tetrameric HbIIIF. A correlation is found between the gamma max of the 600-A charge-transfer absorption band and the Fe-F bond length. Elongation of the Fe-F bond is associated with a shift of the absorption spectral maximum to a longer wavelength. However, the absorption spectral shift induced by the inositsol hexaphosphate induced R leads to T conversion does not result from a change in the Fe-F stretching frequency (+/- 0.5 cm-1). In contrast, frequency shifts are observed for heme macrocyclic vibrational modes. The data are interpreted to indicate that the effect of the R leads to T conversion in HbIIIF is to perturb heme macrocycle conformation without altering the heme out-of-plane iron distance or the Fe-F bond length.
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44
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Lord RC, Mendelsohn R. Raman spectroscopy of membrane constituents and related molecules. MOLECULAR BIOLOGY, BIOCHEMISTRY, AND BIOPHYSICS 1981; 31:377-436. [PMID: 7015109 DOI: 10.1007/978-3-642-81537-9_8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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45
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Karplus M, McCammon JA. The internal dynamics of globular proteins. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1981; 9:293-349. [PMID: 7009056 DOI: 10.3109/10409238109105437] [Citation(s) in RCA: 422] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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46
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47
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Hseu TH, Chang H. Laser Raman studies on the conformation of Pro-Leu-Gly-NH2. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 624:340-5. [PMID: 6106507 DOI: 10.1016/0005-2795(80)90075-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Laser Raman spectra of Pro-Leu-Gly-NH2, the factor that inhibits release of pituitary melanotropin, have been obtained in the solid state, in dimethylsuloxide and in aqueous solution. The amide I frequencies were observed at 1650 and 1687 cm-1 in the solid state and at 1669 cm-1 in dimethylsulfoxide. The conformation of this tripeptide has been proposed by 1H-NMR studies in [2H]-dimethylsulfoxide and revealed by X-ray analysis to be type II beta-turn. These observed amide I frequencies thus are characteristic of type II beta-turn conformation. The relatively lower amide I frequency, 1645 cm-1, observed in 2H2O indicates that the conformation of the peptide in aqueous solution could be different from those in solid state and in dimethylsulfoxide. pH changes hae no significant effect on aqueous solution spectra, except for the shape of the amide III band. The maximum of the amide III band shifted from 1259 cm-1 at pH 2.0 to 1242 cm-1 at pH 11.7. The amide III peaks in the solid state were at 1234 and 1268 cm-1.
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48
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Pézolet M, Pigeon-Gosselin M, Nadeau J, Caillé JP. Laser Raman scattering. A molecular probe of the contractile state of intact single muscle fibers. Biophys J 1980; 31:1-8. [PMID: 7272428 PMCID: PMC1328760 DOI: 10.1016/s0006-3495(80)85036-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The 500 to 1,800-cm-1 region of the Raman spectra of intact single muscle fibers from the giant barnacle are dominated by bands caused by the protein component of the fibers. The frequency and the intensity of the conformationally sensitive bands indicate that the contractile proteins adopt a predominantly alpha-helical structure and are not affected when the contractile state of the fibers is changed from relaxed to contracted by addition of ATP and Ca. However, the contraction induces a decrease of the scattering intensity of some of the Raman bands caused by the acidic and tryptophan side chains, showing that these amino acids are involved during the generation of tension.
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49
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Lippert JL, Lindsay RM, Schultz R. Laser-Raman investigation of lysozyme-phospholipid interactions. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 599:32-41. [PMID: 7397154 DOI: 10.1016/0005-2736(80)90054-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The interaction of lysozyme with mixed 1,2-dipalmitoyl-L-phosphatidic acid/1,2-dimyristoyl-L-phosphatidylcholine liposomes was investigated by laser Raman spectroscopy. Substantial changes were observed i the spectra of both the lipid and protein in the mixed liposomes over the range 10-62 degrees C. At temperatures below 27 degrees C, interaction with lipid appears to slightly increase the amount of helical structure in lysozyme at the expense of random conformation. At temperatures above 30 degrees C, considerable beta-sheet is irreversibly formed. Onset of beta-formation appears to coincide with the formation of disordered lipid side-chains in the acidic component of the lipid. At all temperatures, the O-P-O diester stretching mode at 782 cm-1 is much more intense in the lipid/protein mixture than in lipid alone. It is observed that the dimyristoyl phosphatidylcholine chain-disorder transition is lowered by 3 degrees C, while that of the phosphatidic acid is lowered by 12 degrees C, yet the post-transition conformation contains a significantly higher proportion of trans-segments in the presence of lysozyme. These results are interpreted in terms of: (1) a polar interaction between acidic phospholipid and lysozyme at temperatures below either chain-disorder transition, in which lysozyme is essentially excluded from the hydrophobic portion of the lipid and (2) an interaction at higher temperatures which involves the lipid side-chains of dipalmitoyl phosphatidic acid in the disordered state and is manifested by a substantial conformational change.
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50
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Fox JW, Tu AT. Laser raman spectroscopic analysis of angiotensin peptides' conformation. Arch Biochem Biophys 1980; 201:375-83. [PMID: 7396514 DOI: 10.1016/0003-9861(80)90525-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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