Biospectroscopy最新文献

{"title":"EPR spectroscopy: A powerful technique for the structural and functional investigation of metalloproteins","authors":"Claude More,&nbsp;Valérie Belle,&nbsp;Marcel Asso,&nbsp;André Fournel,&nbsp;Guy Roger,&nbsp;Bruno Guigliarelli,&nbsp;Patrick Bertrand","doi":"10.1002/(SICI)1520-6343(1999)5:5+<S3::AID-BSPY2>3.0.CO;2-P","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5+<S3::AID-BSPY2>3.0.CO;2-P","url":null,"abstract":"<p>Numerous metal centers in proteins can be prepared in a redox state in which their ground state is paramagnetic. Complementary data provided by EPR, Mössbauer, electron nuclear double resonance, magnetic circular dichroism, and NMR spectroscopies have therefore played a major role in the elucidation of the structure and function of these centers. Among those techniques the most commonly used is certainly EPR spectroscopy. In this article various aspects of the current applications of EPR to the structural and functional study of metalloproteins are presented. They are illustrated by recent studies carried out in our laboratory in the field of metalloenzymes and electron transfer systems. The power of numerical simulation techniques is emphasized throughout this work. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: S3–S18, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 S5","pages":"S3-S18"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5+<S3::AID-BSPY2>3.0.CO;2-P","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21374428","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 circular dichroism of gramicidin D in organic solvents","authors":"Chunxia Zhao,&nbsp;Prasad L. Polavarapu","doi":"10.1002/(SICI)1520-6343(1999)5:5<276::AID-BSPY2>3.0.CO;2-8","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5<276::AID-BSPY2>3.0.CO;2-8","url":null,"abstract":"<p>The vibrational circular dichroism (VCD) and absorption spectra of gramicidin D in different organic solvents are presented in the amide I and II regions. The absorption and VCD spectra suggest that gramicidin structures are similar in dioxane and chloroform. However, the structures adopted by gramicidin in chloroform are due to the trace amount of protective ethanol present in chloroform solvent. In the absence of this protective ethanol, gramicidin appears to aggregate in chloroform. The gramicidin structures appear to be similar in propanol and ethanol, but the composition of these structures appear to be different from those in dioxane and chloroform. In methanol-<i>d</i>₄, a different composition of structures, including monomers, appears to be present. The structures in dimethyl-<i>d</i>₆-sulfoxide and 2,2,2-trifluoroethanol are entirely different from those in all other solvents. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: 276–283, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 5","pages":"276-283"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5<276::AID-BSPY2>3.0.CO;2-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81312254","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":"Resonance Raman studies of the heme–ligand active site of hemoglobin I from Lucina pectinata","authors":"Jose Cerda,&nbsp;Yolanda Echevarria,&nbsp;Erick Morales,&nbsp;Juan López-Garriga","doi":"10.1002/(SICI)1520-6343(1999)5:5<289::AID-BSPY4>3.0.CO;2-X","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5<289::AID-BSPY4>3.0.CO;2-X","url":null,"abstract":"<p>Hemoglobin I from the clam <i>Lucina pectinata</i> has the unusual ability to bind hydrogen sulfide. This sulfide-reactive hemoglobin has a high content of phenyl residues in the heme pocket that may account for its ligand binding properties. To confirm this, resonance Raman spectroscopy was used to determine the heme structure of deoxy, oxy, carbon monoxy, metaquo, metcyano, and methydrogen sulfide hemoglobin I (HbI) complexes. The oxidation (ν₄), spin (ν₃), and coordination (ν₂) markers were identified in the high-frequency spectra of all the HbI complexes. The data indicated that the aromatic environment near the heme does not affect the iron oxidation state, coordination state, spin state, and core size marker vibrational modes. The marker bands also revealed that metsulfide HbI complex has an Fe(III), six-coordinate, and low-spin structure. The low-frequency vibrational frequencies for the methydrogen sulfide, metcyano, oxy, and carbon monoxy HbI derivatives showed νFe–S at 374 cm⁻¹, νFe–C at 448 cm⁻¹, νFe–O at 563 cm⁻¹, and νFe–C 516 cm⁻¹, respectively. These results suggest a model where the phenyl residues in the Phe29(B10) and Phe68(E11) positions have strong electrostatic interactions with the metcyano, oxy, and carbon monoxy ligands of the HbIO₂, HbICO, and HbICN complexes. The multipolar interaction explains the higher νFe–C frequency for the carbon monoxy HbI complex, and the lower νCO, νFe–O₂ and νFe–C frequencies for the HbICO, HbIO₂, and HbICN complexes, respectively. The repulsion between the carbonyl group of Gln64(E7) and oxygen or nitrogen of the oxy, carbon monoxy, and metcyano HbI complexes would also contribute to the above behavior. This model implies that Gln64(E7), in HbI <i>Lucina pectinata</i>, does not rotate from its original position to stabilize, by means of hydrogen bonding, the coordination of the other ligands, for example, the metcyano, oxy, and carbon monoxy heme complexes. Instead the electronic interaction between the phenylalanine in B10 and E11 positions stabilize these HbI complexes. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: 289–301, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 5","pages":"289-301"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5<289::AID-BSPY4>3.0.CO;2-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85622026","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":"Temperature dependent quaternary state relaxation in sol–gel encapsulated hemoglobin","authors":"Tapan Kanti Das,&nbsp;Imran Khan,&nbsp;Denis L. Rousseau,&nbsp;Joel M. Friedman","doi":"10.1002/(SICI)1520-6343(1999)5:5+<S64::AID-BSPY7>3.0.CO;2-W","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5+<S64::AID-BSPY7>3.0.CO;2-W","url":null,"abstract":"<p>Samples of human adult hemoglobin (HbA) encapsulated in a wet porous sol–gel are prepared under aerobic and anaerobic conditions. Resonance Raman spectroscopy is used to compare equilibrium deoxyHbA to the nonequilibrium deoxy species generated by deoxygenating an encapsulated oxyHbA sample. The spectra of the deoxygenated samples as a function of delay subsequent to deoxygenation reveal a marked slow down by the gel of the two phases of relaxation: the tertiary relaxation associated with the transition from the liganded R to deoxy R conformations and the quaternary relaxation associated with the deoxy R to deoxy T transition. The temperature dependence (4–80°C) of the relaxation indicates that the internal viscosity of the gel is greatly enhanced at the lower temperatures. At 80°C the tertiary and quaternary relaxations occur over minutes to hours, respectively, whereas at 4°C both relaxations are essentially frozen. These results demonstrate the impressive potential of using sol–gel encapsulation as a means of studying substrate binding induced conformational changes in proteins. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: S64–S70, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 S5","pages":"S64-S70"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5+<S64::AID-BSPY7>3.0.CO;2-W","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21374370","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":"Special issue on bioinorganic spectroscopy","authors":"Giulietta Smulevich","doi":"10.1002/(SICI)1520-6343(1999)5:5+<S1::AID-BSPY1>3.0.CO;2-U","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5+<S1::AID-BSPY1>3.0.CO;2-U","url":null,"abstract":"","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 S5","pages":"S1-S2"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5+<S1::AID-BSPY1>3.0.CO;2-U","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89817857","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 and functional studies of monomeric mutant of Cu–Zn superoxide dismutase without Arg 143","authors":"Lucia Banci,&nbsp;Ivano Bertini,&nbsp;Rebecca Del Conte,&nbsp;Maria Silvia Viezzoli","doi":"10.1002/(SICI)1520-6343(1999)5:5+<S33::AID-BSPY4>3.0.CO;2-E","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5+<S33::AID-BSPY4>3.0.CO;2-E","url":null,"abstract":"<p>Mutation of arginine (Arg) 143 with Ile in the monomeric mutant (Phe50Glu, Gly51Glu, Val148Lys, Ile151Lys) of copper–zinc superoxide dismutase (R143I M4SOD, where M4SOD is the above mutant) leads to a protein with low copper content. Cobalt(II) binds the demetalized protein with a low and comparable affinity for the two metal sites, whereas it binds first and stochiometrically at the zinc site in the M4SOD protein and in the dimeric wild type SOD. However, a CuCo SOD derivative can be obtained whose NMR spectra indicate the structural changes induced by monomerization plus those induced by the Arg → Ile mutation. The electronic, circular dichroism, and EPR spectra provide structural information on the copper site. The low activity of the enzyme is accounted for on the basis of the structural properties of the active cavity. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: S33–S41, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 S5","pages":"S33-S41"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5+<S33::AID-BSPY4>3.0.CO;2-E","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21374430","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":"Binding of the cationic 5-coordinate Zn(II)-5,10,15,20-tetrakis(4-N-methylpyridyl)porphyrin to DNA and model polynucleotides: Ionic-strength dependent intercalation in [poly(dG-dC)]2","authors":"Vladimir S. Chirvony,&nbsp;Victor A. Galievsky,&nbsp;Sergei N. Terekhov,&nbsp;Boris M. Dzhagarov,&nbsp;Vladimir V. Ermolenkov,&nbsp;Pierre-Yves Turpin","doi":"10.1002/(SICI)1520-6343(1999)5:5<302::AID-BSPY5>3.0.CO;2-N","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5<302::AID-BSPY5>3.0.CO;2-N","url":null,"abstract":"<p>The localization of the water-soluble cationic porphyrin ZnTMpyP(4) [Zn(II) derivative of 5,10,15,20-tetrakis(4-<i>N</i>-methylpyridyl)porphyrin] in its complex with [poly(dG-dC)]₂ is studied as a function of the solution ionic strength μ (μ = 0.20–0.03). It is shown that the position of the Soret band maximum of ZnTMpyP(4) shifts from 436 to 446 nm on complexation, while its intensity markedly decreases (∼40%) when μ decreases from 0.20 to 0.03. This suggests that the porphyrin is mainly intercalated in [poly(dG-dC)]₂ at μ = 0.03. Shifts of resonance Raman marker lines under ZnTMpyP(4) complexation to [poly(dG-dC)]₂ at μ = 0.03 also support porphyrin intercalation. At last, a time-resolved transient absorption study of the porphyrin triplet state quenching by molecular oxygen shows that, at μ = 0.03, biexponential kinetics of triplet state quenching is observed with time constants ∼12 μs (40%) and ∼35 μs (60%), that is, much longer than that of the free ZnTMpyP(4) species (∼3 μs). Such a strong “shielding effect” of [poly(dG-dC)]₂, resulting in the ∼35-μs component, is characteristic for porphyrin intercalation. The other component at ∼12 μs likely corresponds to a less protected, “partially intercalated” species in the polynucleotide. It is assumed that a decrease of the ionic strength μ (in terms of Na⁺ concentration) decreases the neutralization of the negative charges of the polynucleotide phosphate groups and, therefore, allows cationic ZnTMpyP(4) molecules to come closer to the nucleotides, this favoring, in a second step, full (or partial) intercalation. Since ZnTMpyP(4) is known to be axially ligated by a H₂O molecule, intercalation undoubtedly must result in a loss of its axial ligand. As far as we know, this is the first observation of such an axial ligand release in metalloporphyrin, induced by intercalation in a DNA sequence. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: 302–312, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 5","pages":"302-312"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5<302::AID-BSPY5>3.0.CO;2-N","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81292209","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":"Nitration of internal tyrosine of cytochrome c probed by resonance Raman scattering","authors":"L. Quaroni,&nbsp;W. E. Smith","doi":"10.1002/(SICI)1520-6343(1999)5:5+<S71::AID-BSPY8>3.0.CO;2-T","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5+<S71::AID-BSPY8>3.0.CO;2-T","url":null,"abstract":"<p>Tyrosines can be selectively nitrated in a protein and the resultant chromophore can be used as an <i>in situ</i> probe of the tyrosine environment. Resonance Raman scattering could have specific advantages as a detection method because of the inherent selectivity of the technique and because shifts in the intensity and frequency of the nitro stretch can be detected and related to the form and environment of the nitrotyrosine. To evaluate this possibility the internal residue Tyr₆₇ of cytochrome <i>c</i> was nitrated and resonance Raman scattering was recorded. With 413.1-nm excitation the resonance scattering from the heme protein dominates, but with 457.9-nm excitation intense bands due to nitrostretching vibrations are readily observed. The frequency of the internal Tyr₆₇ indicates an aqueous environment that suggests that on nitration this residue becomes exposed on the protein surface or that water enters the active pocket. pH dependent measurements can be used to follow the protonation of the residue. A p<i>K</i>_<i>a</i> of approximately 7 also indicates an aqueous environment. This initial study indicates that resonance Raman scattering does have unique advantages as an <i>in situ</i> probe of the local structure of nitrated tyrosine residues. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: S71–S76, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 S5","pages":"S71-S76"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5+<S71::AID-BSPY8>3.0.CO;2-T","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21374371","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":"Paramagnetic NMR studies of blue and purple copper proteins","authors":"Urszula Kolczak,&nbsp;Jesús Salgado,&nbsp;Gregg Siegal,&nbsp;Matti Saraste,&nbsp;Gerard W. Canters","doi":"10.1002/(SICI)1520-6343(1999)5:5+<S19::AID-BSPY3>3.0.CO;2-H","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5+<S19::AID-BSPY3>3.0.CO;2-H","url":null,"abstract":"<p>¹H- and ¹³C-NMR spectroscopy is applied to investigate the Cu_A and type 1 active sites of copper proteins in solution. The analysis of hyperfine shifted ¹H resonances allows the comparison of the electron spin density delocalization in the Cu_A site of the wild-type soluble domains of various cytochrome <i>c</i> oxidases (<i>Thermus thermophilus</i>,<i> Paracoccus denitrificans</i>, and <i>Paracoccus versutus</i>) and genetically engineered constructs (soluble domain of quinol oxidase from <i>Escherichia coli</i> and <i>Thiobacillus versutus</i> amicyanin). Comparable spin densities are found on the two terminal His ligands for the wild-type constructs as opposed to the engineered proteins where the spin is more unevenly distributed on the two His residues. A reevaluation of the Cys H^β chemical shifts that is in agreement with the data published for both the <i>P</i>.<i> denitrificans</i> and the <i>P</i>.<i> versutus</i> Cu_A soluble domains confirms the thermal accessibility of the ²B_3u electronic excited state and indicates the existence of slightly different spin densities on the two bridging Cys ligands. The ¹³C-NMR spectrum of isotopically enriched oxidized azurin from <i>Pseudomonas aeruginosa</i> reveals six fast relaxing signals, which can be partially identified by 1- and 2-dimensional (1-D, 2-D) direct detection techniques combined with 3-D triple resonance experiments. The observed contact shifts suggest the presence of direct spin density transfer and spin polarization mechanisms for the delocalization of the unpaired electron. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: S19–S32, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 S5","pages":"S19-S32"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5+<S19::AID-BSPY3>3.0.CO;2-H","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21374429","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":"Analysis and interpretation of infrared microscopic maps: Visualization and classification of skin components by digital staining and multivariate analysis","authors":"Laura M. McIntosh,&nbsp;James R. Mansfield,&nbsp;A. Neil Crowson,&nbsp;Henry H. Mantsch,&nbsp;Michael Jackson","doi":"10.1002/(SICI)1520-6343(1999)5:5<265::AID-BSPY1>3.0.CO;2-F","DOIUrl":"10.1002/(SICI)1520-6343(1999)5:5<265::AID-BSPY1>3.0.CO;2-F","url":null,"abstract":"<p>Four analytical methods have been applied to infrared microscopic maps of human skin which contained basal cell carcinoma tumors—namely, point spectroscopy, grayscale functional group mapping, digital staining, and fuzzy C-means (FCM) cluster analysis. Spectroscopic interpretation using point spectroscopy allowed discrimination between normal and tumor-bearing skin components. Functional group mapping provided information on the distribution of lipids, proteins, nucleic acids, and collagen within skin sections. While functional group mapping only allowed examination of one material (or a ratio of two materials) at a time, a new approach termed <i>digital staining</i> allowed visualization of the distribution of up to three materials at one time. Digital staining thus gave a more detailed understanding of the tissue section. Finally, application of FCM cluster analysis, a nonsubjective, unsupervised classification methodology, allowed us to group spectra into five distinct clusters, which correlated to distinct tissue components in skin. Tumor-bearing skin was clearly separated from normal skin. When different analytical methods are used in conjunction, a unique understanding of tissues can be obtained. Our results demonstrate that infrared microscopy has potential for the pathological diagnosis of skin tumors. © 1999 John Wiley &amp; Sons, Inc. Biospectroscopy 5: 265–275, 1999</p>","PeriodicalId":9037,"journal":{"name":"Biospectroscopy","volume":"5 5","pages":"265-275"},"PeriodicalIF":0.0,"publicationDate":"1999-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(SICI)1520-6343(1999)5:5<265::AID-BSPY1>3.0.CO;2-F","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90329845","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}