Biospectroscopy最新文献

{"title":"Cyanide binding and active site structure in heme-copper oxidases: Normal coordinate analysis of iron-cyanide vibrations of CN− complexes of cytochromes ba3 and aa3","authors":"Younkyoo Kim,&nbsp;Gerald T. Babcock,&nbsp;Kristene K. Surerus,&nbsp;James A. Fee,&nbsp;R. Brian Dyer,&nbsp;William H. Woodruff,&nbsp;W. Anthony Oertling","doi":"10.1002/(SICI)1520-6343(1998)4:1<1::AID-BSPY1>3.0.CO;2-A","DOIUrl":"10.1002/(SICI)1520-6343(1998)4:1<1::AID-BSPY1>3.0.CO;2-A","url":null,"abstract":"<p>The cyanide isotope-sensitive low-frequency vibrations of ferrous cyano complexes of cytochrome <i>a</i>₃ are studied for cytochrome <i>ba</i>₃ from <i>Thermus thermophilus</i> and cytochrome <i>aa</i>₃ from bovine heart. Cyanide complexes of <i>ba</i>₃ display three isotope sensitive frequencies at 512, 485, and 473 cm⁻¹. The first is primarily an Fe—C stretching motion, whereas the lower wavenumber modes are bending motions. These iron-cyanide vibrations are independent of the redox levels of the other metal centers in the protein. On the other hand, the fully reduced bovine derivative complexed with cyanide gives rise to a bending vibration at 503 cm⁻¹ and a stretching vibration at 469 cm⁻¹. That is, the ordering of the stretching and bending frequencies is reversed from that of the bacterial protein. These results are analyzed by normal coordinate calculations to obtain comparative models for the binuclear O₂ reducing site of the two proteins. We find that the observed frequencies are consistent with a linear Fe—C—N group and larger Fe—C stretching force constant (2.558 mdyn/Å) for <i>ba</i>₃ and a slightly bent Fe—C—N group (angle ∼ 170°) and a smaller Fe—C stretching force constant (2.335 mdyn/Å) for <i>aa</i>₃. Thus, there are significant differences in the interaction of cyanide with ferrous <i>a</i>₃ in the two proteins that are most likely caused by a weaker proximal histidine interaction and stronger peripheral heme electron withdrawing effects in <i>ba</i>₃. Possible sources of these protein-induced effects are discussed. Using the analysis developed here, comparison of the FeCN stretching and bending frequencies of the ferrous bovine <i>a</i>₃-CN complex to those obtained from the ferric <i>a</i>₃-CN complex suggests that upon conversion of the resting to the fully reduced protein, a conformational change occurs that constrains the ligand binding site. © 1998 John Wiley &amp; Sons, Inc. Biospectroscopy 4: 1–15, 1998</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"4 1","pages":"1-15"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1998)4:1<1::AID-BSPY1>3.0.CO;2-A","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20469934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural study of quercetin by vibrational and electronic spectroscopies combined with semiempirical calculations","authors":"J. P. Cornard,&nbsp;J. C. Merlin,&nbsp;A. C. Boudet,&nbsp;L. Vrielynck","doi":"10.1002/(SICI)1520-6343(1997)3:3<183::AID-BSPY2>3.0.CO;2-7","DOIUrl":"10.1002/(SICI)1520-6343(1997)3:3<183::AID-BSPY2>3.0.CO;2-7","url":null,"abstract":"<p>As a follow-up to structural studies of monohydroxylated flavones, the structural and spectroscopic properties of a tetrahydroxylated flavone, the quercetin molecule, have been investigated. The molecular conformation of quercetin has been obtained from semiempirical treatment with the AM1 Hamiltonian. Some structural modifications have been observed between the molecule in the solid state and in an isolated state, notably in the rotation of the phenyl ring with respect to chromone part of the compound. The theoretical model has been validated by both vibrational and electronic spectroscopies. The calculated vibrational and UV-vis spectra are in good accordance with the experiments. The Raman spectra have been assigned, and the main electronic transitions involved in the absorption spectrum have been characterized. © 1997 John Wiley &amp; Sons, Inc. Biospect 3: 183–193, 1997</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"3 3","pages":"183-193"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1997)3:3<183::AID-BSPY2>3.0.CO;2-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79380188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A spectroscopic investigation of the formation mechanism of pigment gallstones","authors":"J.-G. Wu,&nbsp;X.-S. Zhou,&nbsp;Z. Xu,&nbsp;T. Shen,&nbsp;Y.-Z. Xu,&nbsp;W.-H. Li,&nbsp;D.-F. Xu,&nbsp;R. D. Soloway,&nbsp;E. Wentrup-Byrne,&nbsp;Z.-H. Xu,&nbsp;J.-S. Shi,&nbsp;G.-R. Shen,&nbsp;S.-Q. Deng,&nbsp;X.-F. Li,&nbsp;N. Shi","doi":"10.1002/(SICI)1520-6343(1997)3:5<381::AID-BSPY5>3.0.CO;2-5","DOIUrl":"10.1002/(SICI)1520-6343(1997)3:5<381::AID-BSPY5>3.0.CO;2-5","url":null,"abstract":"<p>Further spectroscopic studies of gallstones are reviewed with an emphasis on the formation of black pigment gallstones. This type of gallstone appears mainly in Western countries, with only 3% of the cholelithiasis patients in China having black gallstones. Fourier transform infrared absorption and electron paramagnetic resonance are used as spectroscopic probes of gallstones and their metal bilirubinate components. Nonlinear phenomena in gallstone formation were investigated through the appearance of ring structure in gallstones and fractal patterns in the formation in the precipitates of bile salt systems. Although a complete understanding of gallstone formation has not yet been achieved, interesting progress toward this goal has been made recently. © 1997 John Wiley &amp; Sons, Inc. Biospectroscopy <b>3:</b> 381–391, 1997</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"3 5","pages":"381-391"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1997)3:5<381::AID-BSPY5>3.0.CO;2-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76535660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FTIR microspectroscopic study of cell types and potential confounding variables in screening for cervical malignancies","authors":"Bayden R. Wood,&nbsp;Michael A. Quinn,&nbsp;Brian Tait,&nbsp;Martin Ashdown,&nbsp;Tracy Hislop,&nbsp;Melissa Romeo,&nbsp;Don McNaughton","doi":"10.1002/(SICI)1520-6343(1998)4:2<75::AID-BSPY1>3.0.CO;2-R","DOIUrl":"10.1002/(SICI)1520-6343(1998)4:2<75::AID-BSPY1>3.0.CO;2-R","url":null,"abstract":"<p>FTIR microscopy was applied to the analysis of cell types and other variables present in Pap smears to ascertain the limitations of infrared spectroscopy in the diagnosis of cervical cancer and dysplasia. It was found that leukocytes, and in particular lymphocytes, have spectral features in the phophodiester region (1300-900 cm⁻¹) suggestive of what has previously been described as changes indicative of malignancy. Endocervical cells and fibroblasts have similar spectral features to HeLa cells and consequently could also confound diagnosis. The use of ethanol as a fixative and dehydrating agent results in retention of glycogen in cervical cell types and thus minimizes spectral changes in the glycogen region due to sampling technique. Spectra of seminal fluids exhibit strong bands in the phosphodiester/carbohydrate region; however, sperm contamination should be easily detectable by the presence of a distinctive doublet at 981/968 cm⁻¹. Erythrocyte spectra exhibit a reduction in glycogen band intensity, but can be discerned by a relatively low-intensity ν_<i>s</i> <span></span> band. Endocervical mucin spectra exhibit a reduction in glycogen bands and a very pronounced ν_<i>s</i> <span></span> band, which is similar in intensity to the corresponding band in HeLa cells. Thrombocytes have strong bands in the phosphodiester region, but thrombocytes can be discerned from other cell types by the presence of two small broad bands at 980 and 935 cm⁻¹. <i>Candida albicans</i> is characterized by strong bands in the polysaccharide region which could potentially obscure diagnostic bands if <i>C. albicans</i> is present in large numbers. Spectra of bacteria common to the female genital tract, in general, also have strong absorptions in the polysaccharide region; however, bacterial contamination is usually minimal and would not be expected to obscure cervical cell spectra. Nylon threads and bristles from cervical sampling implements produce characteristic IR profiles which allow for easy identification. Given the number of potential confounding variables associated with cervical cytology, a multivariate statistical or neural network analysis would appear to be necessary before the implementation of FTIR technology in clinical laboratories. © 1998 John Wiley &amp; Sons, Inc. Biospectroscopy 4: 75–91, 1998</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"4 2","pages":"75-91"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1998)4:2<75::AID-BSPY1>3.0.CO;2-R","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80667588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A spectroscopic study of the hydrogen bonding and π–π stacking interactions of harmane with quinoline","authors":"Manuel Balón,&nbsp;Pilar Guardado,&nbsp;María A. Muñoz,&nbsp;Carmen Carmona","doi":"10.1002/(SICI)1520-6343(1998)4:3<185::AID-BSPY4>3.0.CO;2-3","DOIUrl":"10.1002/(SICI)1520-6343(1998)4:3<185::AID-BSPY4>3.0.CO;2-3","url":null,"abstract":"<p>A spectroscopic (UV–vis, Fourier transform IR, steady state, and time-resolved fluorescence) study of the interactions of the ground and excited singlet states of harmane (1-methyl-9H-pyrido/3,4-b/indole) with quinoline has been carried out in cyclohexane, toluene, and buffered pH = 8.7 aqueous solutions. To analyze how the number of rings in the substrate influences these interactions, pyridine and phenanthridine have also been included in this study. In cyclohexane and toluene 1 : 1 stoichiometric hydrogen-bonded complexes are formed in both the ground and the excited singlet states. As the number of rings of the benzopyridines and the solvent polarity increase hydrogen-bonding interactions weaken and π–π van der Waals interactions become apparent. © 1998 John Wiley &amp; Sons, Inc. Biospectroscopy 4: 185–195, 1998</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"4 3","pages":"185-195"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1998)4:3<185::AID-BSPY4>3.0.CO;2-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20557729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chlorophyll and pheophytin derivatives in geochemical transformation pathways: A surface-enhanced resonance Raman spectroscopic study","authors":"Paul S. Woolley,&nbsp;Brendan J. Keely,&nbsp;Ronald E. Hester","doi":"10.1002/(SICI)1520-6343(1998)4:3<147::AID-BSPY1>3.0.CO;2-1","DOIUrl":"10.1002/(SICI)1520-6343(1998)4:3<147::AID-BSPY1>3.0.CO;2-1","url":null,"abstract":"<p>Protected surface-enhanced resonance Raman spectroscopy (PSERRS) has been used to study a number of chlorophyll transformation products that have been suggested as intermediates in the so-called Treibs hypothesis which describes the transformation of ancient chlorophyll <i>a</i> (chl<i>a</i>) in the biosphere into desoxophylloerythroetioporphyrin (DPEP) found in sedimentary environments. Both Soret- and <i>Q_y</i>-resonant PSERR spectra have been recorded, providing two-dimensional structural fingerprints containing a number of bands which enable the presence of specific peripheral substituents to be identified. Some of these marker bands can be assigned directly to vibrational modes of the particular substituents. This has allowed further characterization of the vibrational spectrum of chl <i>a</i>; in particular, a vinyl mode has been identified which previously was thought to be Raman silent. © 1998 John Wiley &amp; Sons, Inc. Biospectroscopy 4: 147–159, 1998</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"4 3","pages":"147-159"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1998)4:3<147::AID-BSPY1>3.0.CO;2-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20557818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface-enhanced Raman spectroscopy of γ-aminobutyric acid on silver colloid surfaces","authors":"J. L. Castro,&nbsp;S. Sanchez-Cortes,&nbsp;J. V. Garcia Ramos,&nbsp;J. C. Otero,&nbsp;J. I. Marcos","doi":"10.1002/(SICI)1520-6343(1997)3:6<449::AID-BSPY4>3.0.CO;2-W","DOIUrl":"10.1002/(SICI)1520-6343(1997)3:6<449::AID-BSPY4>3.0.CO;2-W","url":null,"abstract":"<p>The surface-enhanced Raman spectroscopy (SERS) of γ-aminobutyric acid (GABA) adsorbed on silver colloids in H₂O and D₂O were recorded and analyzed. When the concentration is greater than 10⁻³ <i>M</i>, the adsorbed species is the anionic form of the amino acid that interacts with the surface through both functional groups. According to the vibrational interpretation of the spectra, it is assumed that at concentrations in the order of or less than 10⁻³ <i>M</i>, GABA undergoes chemical transformations, which increase upon dilution, and spectra are recorded that are the result of the competitive adsorption between the amino acid in its anionic form and the products resulting from the chemical transformations. © 1997 John Wiley &amp; Sons, Inc. Biospectroscopy <b>3:</b> 449–455, 1997</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"3 6","pages":"449-455"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1997)3:6<449::AID-BSPY4>3.0.CO;2-W","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75729276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vibrational study of phosphate modes in GDP and GTP and their interaction with magnesium in aqueous solution","authors":"J. H. Wang,&nbsp;D. G. Xiao,&nbsp;H. Deng,&nbsp;Robert Callender,&nbsp;Martin R. Webb","doi":"10.1002/(SICI)1520-6343(1998)4:4<219::AID-BSPY1>3.0.CO;2-Y","DOIUrl":"10.1002/(SICI)1520-6343(1998)4:4<219::AID-BSPY1>3.0.CO;2-Y","url":null,"abstract":"<p>Raman and infrared spectra were examined for guanosine 5′-diphosphate (GDP) and guanosine 5′-triphosphate (GTP) in aqueous solution. The vibrational modes were assigned on the basis of isotopic frequency shifts and relative intensities in the Raman and infrared spectra. The observed frequency shifts on ¹⁸O isotope labeling made it possible to identify the bands from each phosphate group (α, β, γ). Frequency shifts were observed as Mg²⁺ complexes with GDP and GTP. The results suggested that Mg²⁺ binds to GDP in a bidentate manner to the α, β P · · O bonds and in a tridentate manner to the α, β and γ P · · O bonds of Mg·GTP. The results indicate that structure of Mg²⁺ coordinated to GTP in aqueous solution differs somewhat to that found for Mg·ATP. © 1998 John Wiley &amp; Sons, Inc. Biospectroscopy 4: 219–227, 1998</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"4 4","pages":"219-227"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1998)4:4<219::AID-BSPY1>3.0.CO;2-Y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72607470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interaction configurations of H2O molecules absorbed in isolated plant cuticles by infrared spectrometry","authors":"Yves Maréchal,&nbsp;André Chamel","doi":"10.1002/(SICI)1520-6343(1997)3:2<143::AID-BSPY7>3.0.CO;2-8","DOIUrl":"10.1002/(SICI)1520-6343(1997)3:2<143::AID-BSPY7>3.0.CO;2-8","url":null,"abstract":"<p>In a previous article, spectrometric arguments were used to determine the two interaction configurations adopted by H₂O molecules present in isolated ivy leaf cuticles which are in equilibrium with atmospheric water molecules. In this article, on the same basis, the configurations of H₂O molecules at a higher concentration of water supplied as a droplet deposited on cuticle surfaces are determined. Addition of heavy water allows us to determine the single alcohol site which exchanges its H atom with a D atom in these conditions. The majority of added molecules which are inserted in the cuticle adopt configurations similar to those of volatile H₂O molecules which are in equilibrium with atmosphere. An appreciable number of molecules, however, display new configurations. These results show the interest of infrared spectrometry in following hydration processes in biological membranes. © 1997 John Wiley &amp; Sons, Inc. Biospect <b>3:</b> 143–153, 1997</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"3 2","pages":"143-153"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1997)3:2<143::AID-BSPY7>3.0.CO;2-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79288355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Infrared spectroscopy of human tissue. II. A comparative study of spectra of biopsies of cervical squamous epithelium and of exfoliated cervical cells","authors":"L. Chiriboga,&nbsp;P. Xie,&nbsp;V. Vigorita,&nbsp;D. Zarou,&nbsp;D. Zakim,&nbsp;M. Diem","doi":"10.1002/(SICI)1520-6343(1998)4:1<55::AID-BSPY6>3.0.CO;2-R","DOIUrl":"10.1002/(SICI)1520-6343(1998)4:1<55::AID-BSPY6>3.0.CO;2-R","url":null,"abstract":"<p>A comparison of infrared absorption spectra obtained from the different layers of squamous epithelium from the human cervix, and infrared spectra obtained from exfoliated cervical cells, is presented. Infrared spectroscopy has been shown (in part I of this series) to be a sensitive tool to monitor maturation and differentiation of human cervical cells; therefore, this spectroscopic technique provides new insights into the composition and state of health of exfoliated cells. © 1998 John Wiley &amp; Sons, Inc. Biospectroscopy 4: 55–59, 1998</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"4 1","pages":"55-59"},"PeriodicalIF":0.0,"publicationDate":"1998-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1998)4:1<55::AID-BSPY6>3.0.CO;2-R","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86373973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}