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Author Jallon, J.M.; Risler, Y.; Iwatsubo, M. openurl 
  Title Beef liver L-Glutamate dehydrogenase mechanism: presteady state study of the catalytic reduction of 2.oxoglutarate by NADPH Type Journal Article
  Year 1975 Publication Biochemical and biophysical research communications Abbreviated Journal Biochem Biophys Res Commun  
  Volume 67 Issue 4 Pages 1527-1536  
  Keywords Animals; Cattle; Glutamate Dehydrogenase/*metabolism; Ketoglutaric Acids; Kinetics; Liver/*enzymology; Nadp; Oxidation-Reduction; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-291X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1038 Approved no  
  Call Number Admin @ knut @ Serial (up) 21  
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Author Rodier, F. openurl 
  Title [Spectral properties of porcine plasminogen: study of the acidic transition (author's transl)] Type Journal Article
  Year 1976 Publication European journal of biochemistry / FEBS Abbreviated Journal Eur J Biochem  
  Volume 63 Issue 2 Pages 553-562  
  Keywords Animals; Binding Sites; Guanidines; Hydrogen-Ion Concentration; *Plasminogen; Protein Binding; Protein Conformation; Spectrometry, Fluorescence; Spectrophotometry; Spectrophotometry, Ultraviolet; Swine; Temperature  
  Abstract The acidic transition of porcine plasminogen, prepared by affinity chromatography, was studied by non-destructive methods. These methods are based on the analysis of the behaviour of the tryptophyls under various conditions. The perturbation of the absorption and emission spectra by pH or temperature and the dynamic quenching of the intrinsic fluorescence are used to obtain information on structural changes which affect the environment of these residues. It is shown that by decreasing pH the fluorescence emission spectra are shifted toward the long wavelengths, with a broadening of the fluorescence band. The same effect can be obtained at constant pH by heating the protein solution. In order to analyze these phenomena, it is assumed that the fluorescence intensities at 355 nm and 328 nm reflect the proportion of the tryptophans which are exposed to the solvent, and buried, respectively. The plot of the ratio of the fluorescence intensities at these wavelengths versus pH or temperature leads to a titration curve showing an unmasking of tryptophans. The proportion of exposed tryptophans is measured by the dynamic fluorescence quenching technique and the data analyzed according to Lehrer. The plot of the fraction of exposed tryptophyls versus pH also shows the unmasking of these chromophores. Thermal perturbation of a solution of plaminogen at neutral pH induces a difference absorption spectrum whose amplitudes at the maxima are proportional to the number of exposed aromatic residues. The comparison with a solution of fully denatured plasminogen in 6 M guanidium chloride, where all the tryptophyls are exposed, shows that the percentage of exposure is equal to 59%. This number is significantly higher than the percentage found by the fluorescence quenching technique (20%), indicating that some tryptophyls are located in crevices, exposed to the solvent but not to the iodide. At acidic pH the absorption difference spectra induced by thermal perturbation are not classical, since they show an inversion and a new band between 300 nm and 305 nm. This band is mentioned in the literature as a minor band of tryptophan which appears when this chromophore is located in an asymmetric environment. On plotting the maximum amplitude of these spectra obtained at acidic pH versus temperature, we obtain a curve indicating that two types of antagonistic interactions are involved in the perturbation of the chromophores spectra. The spectrophotometric titration of plasminogen gives classical absorption difference spectra. By plotting the maximum amplitude at 292 nm versus pH, we obtain a titration curve with an apparent pK of 2.9 units. This pK is acidic which respect to the pK value of a normal carboxyl. This low value can be due to a positively charged group in the neighbourhood of a carboxyl, which interacts with one or more chromophores. When the carboxyl becomes protonated, this positively charged group is free and available to perturb the environment of some chromophores...  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language French Summary Language Original Title Proprietes spectrales du plasminogene porcin. Etude de la transition acide  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0014-2956 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:4326 Approved no  
  Call Number Admin @ knut @ Serial (up) 22  
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Author Bykov, S.; Lednev, I.; Ianoul, A.; Mikhonin, A.; Munro, C.; Asher, S.A. doi  openurl
  Title Steady-state and transient ultraviolet resonance Raman spectrometer for the 193-270 nm spectral region Type Journal Article
  Year 2005 Publication Applied Spectroscopy Abbreviated Journal Appl Spectrosc  
  Volume 59 Issue 12 Pages 1541-1552  
  Keywords Animals; Equipment Design; Equipment Failure Analysis; Horses; Kinetics; Metmyoglobin/*analysis; Myocardium/*metabolism; Reproducibility of Results; Sensitivity and Specificity; Spectrophotometry, Ultraviolet/*instrumentation/methods; Spectrum Analysis, Raman/*instrumentation/methods  
  Abstract We describe a state-of-the-art tunable ultraviolet (UV) Raman spectrometer for the 193-270 nm spectral region. This instrument allows for steady-state and transient UV Raman measurements. We utilize a 5 kHz Ti-sapphire continuously tunable laser (approximately 20 ns pulse width) between 193 nm and 240 nm for steady-state measurements. For transient Raman measurements we utilize one Coherent Infinity YAG laser to generate nanosecond infrared (IR) pump laser pulses to generate a temperature jump (T-jump) and a second Coherent Infinity YAG laser that is frequency tripled and Raman shifted into the deep UV (204 nm) for transient UV Raman excitation. Numerous other UV excitation frequencies can be utilized for selective excitation of chromophoric groups for transient Raman measurements. We constructed a subtractive dispersion double monochromator to minimize stray light. We utilize a new charge-coupled device (CCD) camera that responds efficiently to UV light, as opposed to the previous CCD and photodiode detectors, which required intensifiers for detecting UV light. For the T-jump measurements we use a second camera to simultaneously acquire the Raman spectra of the water stretching bands (2500-4000 cm(-1)) whose band-shape and frequency report the sample temperature.  
  Address Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-7028 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16390595 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3767  
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Author Abbruzzetti, S.; Viappiani, C.; Sinibaldi, F.; Santucci, R. openurl 
  Title Kinetics of histidine dissociation from the heme Fe(III) in N-fragment (residues 1-56) of cytochrome c Type Journal Article
  Year 2004 Publication The Protein Journal Abbreviated Journal Protein J  
  Volume 23 Issue 8 Pages 519-527  
  Keywords Animals; Cytochromes c/*chemistry; Enzyme Activation; Histidine/*chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Lasers; Ligands; Peptide Mapping; Photolysis; Spectrophotometry  
  Abstract We have here investigated the dissociation kinetics of the His side chains axially ligated to the heme-iron in the ferric (1-56 residues) N-fragment of horse cyt c. The ligand deligation induced by acidic pH-jump occurs as a biexponential process with different pre-exponential factors, consistent with a structural heterogeneity in solution and the presence of two differently coordinated species. In analogy with GuHCl-denatured cyt c, our data indicate the presence in solution of two ferric forms of the N-fragment characterized by bis-His coordination, as summarized in the following scheme: His18-Fe(III)-His26 <==> His18-Fe(III)-His33. We have found that the pre-exponential factors depend on the extent of the pH-jump. This may be correlated with the different pKa values shown by His26 and His33; due to steric factors, His26 binds to the heme-Fe(III) less strongly than His33, as recently shown by studies on denatured cyt c. Interestingly, the two lifetimes are affected by temperature but not by the extent of the pH-jump. The lower pKa for the deligation reaction required the use of an improved laser pH-jump setup, capable of inducing changes in H+ concentration as large as 1 mM after the end of the laser pulse. For the ferric N-fragment, close activation entropy values have been determined for the two histidines coordinated to the iron; this result significantly differs from that for GuHCl-denatured cyt c, where largely different values of activation entropy were calculated. This underlines the role played by the missing segment (residues 57-104) peptide chain in discriminating deligation of the “nonnative” His from the sixth coordination position of the metal.  
  Address Dipartimento di Fisica, Universita degli Studi di Parma, Parco Area delle Scienze 7/A 43100 Parma, Italy  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1572-3887 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15648974 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3770  
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Author Hirota, S.; Suzuki, M.; Watanabe, Y. openurl 
  Title Hydrophobic effect of trityrosine on heme ligand exchange during folding of cytochrome c Type Journal Article
  Year 2004 Publication Biochemical and Biophysical Research Communications Abbreviated Journal Biochem Biophys Res Commun  
  Volume 314 Issue 2 Pages 452-458  
  Keywords Amino Acids/chemistry; Animals; Cytochromes c/*chemistry; Heme/*chemistry; Histidine/chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium/chemistry; Peptides/chemistry; Protein Folding; Spectrophotometry; Spectrum Analysis, Raman; Tyrosine/*analogs & derivatives/*chemistry  
  Abstract Effect of a hydrophobic peptide on folding of oxidized cytochrome c (cyt c) is studied with trityrosine. Folding of cyt c was initiated by pH jump from 2.3 (acid-unfolded) to 4.2 (folded). The Soret band of the 2-ms transient absorption spectrum during folding decreased its intensity and red-shifted from 397 to 400 nm by interaction with trityrosine, whereas tyrosinol caused no significant effect. The change in the transient absorption spectrum by interaction with trityrosine was similar to that obtained with 100 mM imidazole, which showed that the population of the intermediate His/His coordinated species increased during folding of cyt c by interaction with trityrosine. The absorption change was biphasic, the fast phase (82+/-9s(-1)) corresponding to the transition from the His/H(2)O to the His/Met coordinated species, whereas the slow phase (24+/-3s(-1)) from His/His to His/Met. By addition of trityrosine, the relative ratio of the slow phase increased, due to increase of the His/His species at the initial stage of folding. According to the resonance Raman spectra of cyt c, the high-spin 6-coordinate and low-spin 6-coordinate species were dominated at pH 2.3 and 4.2, respectively, and these species were not affected by addition of trityrosine. These results demonstrated that the His/His species increased by interaction with trityrosine at the initial stage of cyt c folding, whereas the heme coordination structure was not affected by trityrosine when the protein was completely unfolded or folded. Hydrophobic peptides thus may be useful to study the effects of hydrophobic interactions on protein folding.  
  Address Department of Physical Chemistry, Kyoto Pharmaceutical University, Yamashina-ku, 607-8414 Kyoto, Japan. hirota@mb.kyoto-phu.ac.jp  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-291X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:14733927 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3777  
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Author Ballew, R.M.; Sabelko, J.; Gruebele, M. openurl 
  Title Direct observation of fast protein folding: the initial collapse of apomyoglobin Type Journal Article
  Year 1996 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume 93 Issue 12 Pages 5759-5764  
  Keywords Animals; Apoproteins/*chemistry; Circular Dichroism; Horses; Kinetics; Muscle, Skeletal/chemistry; Myoglobin/*chemistry; *Protein Folding; Spectrometry, Fluorescence; Spectrophotometry, Infrared; Temperature  
  Abstract The rapid refolding dynamics of apomyoglobin are followed by a new temperature-jump fluorescence technique on a 15-ns to 0.5-ms time scale in vitro. The apparatus measures the protein-folding history in a single sweep in standard aqueous buffers. The earliest steps during folding to a compact state are observed and are complete in under 20 micros. Experiments on mutants and consideration of steady-state CD and fluorescence spectra indicate that the observed microsecond phase monitors assembly of an A x (H x G) helix subunit. Measurements at different viscosities indicate diffusive behavior even at low viscosities, in agreement with motions of a solvent-exposed protein during the initial collapse.  
  Address School of Chemical Sciences and Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, 61801, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8650166 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3798  
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Author Chiba, K.; Ikai, A.; Kawamura-Konishi, Y.; Kihara, H. doi  openurl
  Title Kinetic study on myoglobin refolding monitored by five optical probe stopped-flow methods Type Journal Article
  Year 1994 Publication Proteins Abbreviated Journal Proteins  
  Volume 19 Issue 2 Pages 110-119  
  Keywords Animals; Chromatography, Gel; Circular Dichroism; Horses; Kinetics; Metmyoglobin/analogs & derivatives/chemistry; Myoglobin/*chemistry; *Protein Folding; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet; Urea  
  Abstract The refolding kinetics of horse cyanometmyoglobin induced by concentration jump of urea was investigated by five optical probe stopped-flow methods: absorption at 422 nm, tryptophyl fluorescence at around 340 nm, circular dichroism (CD) at 222 nm, CD at 260 nm, and CD at 422 nm. In the refolding process, we detected three phases with rate constants of > 1 x 10(2) s-1, (4.5-9.3) s-1, and (2-5) x 10(-3) s-1. In the fastest phase, a substantial amount of secondary structure (approximately 40%) is formed within the dead time of the CD stopped-flow apparatus (10.7 ms). The kinetic intermediate populated in the fastest phase is shown to capture a hemindicyanide, suggesting that a “heme pocket precursor” recognized by hemindicyanide must be constructed within the dead time. In the middle phase, most of secondary and tertiary structures, especially around the captured hemindicyanide, have been constructed. In the slowest phase, we detected a minor structural rearrangement accompanying the ligand-exchange reaction in the fifth coordination of ferric iron. We present a possible model for the refolding process of myoglobin in the presence of the heme group.  
  Address Laboratory of Biodynamics, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0887-3585 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8090705 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3799  
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Author Dyson, H.J.; Beattie, J.K. openurl 
  Title Spin state and unfolding equilibria of ferricytochrome c in acidic solutions Type Journal Article
  Year 1982 Publication The Journal of Biological Chemistry Abbreviated Journal J Biol Chem  
  Volume 257 Issue 5 Pages 2267-2273  
  Keywords Animals; *Cytochrome c Group; Electron Spin Resonance Spectroscopy; Heme; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium; Protein Binding; Protein Conformation; Spectrophotometry; Temperature  
  Abstract Equilibrium, stopped flow, and temperature-jump spectrophotometry have been used to identify processes in the unfolding of ferricytochrome c in acidic aqueous solutions. A relaxation occurring in approximately 100 microseconds involves perturbation of a spin-equilibrium between two folded conformers of the protein with methionine-80 coordinated or dissociated from the heme iron. The protein unfolds more slowly, in milliseconds, with dissociation and protonation of histidine-18. These two transitions appear cooperative in equilibrium measurements at low (0.01 M) ionic strength, but are separated at higher (0.10 M) ionic strength. They are resolved under both conditions in the dynamic measurements. The spin-equilibrium description permits a unified explanation of a number of properties of ferricytochrome c in acidic aqueous solutions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9258 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6277891 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3807  
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Author Saigo, S. openurl 
  Title A transient spin-state change during alkaline isomerization of ferricytochrome c Type Journal Article
  Year 1981 Publication Journal of Biochemistry Abbreviated Journal J Biochem (Tokyo)  
  Volume 89 Issue 6 Pages 1977-1980  
  Keywords Animals; *Cytochrome c Group; Horses; Hydrogen-Ion Concentration; Isomerism; Kinetics; Myocardium/enzymology; Oxidation-Reduction; Spectrophotometry  
  Abstract Kinetic difference spectra during the alkaline isomerization of ferricytochrome c were obtained by the pH-jump method in the range of 540 to 655 nm. The spectrum of the transient intermediate, which appears during the course of the isomerization, was reproduced from the spectra. The intermediate showed an intense absorption band at 600 nm, indicating that it is a high spin or mixed spin species. This is in contrast to the stable neutral and alkaline forms which are low spin species. The transient spin-state change during the isomerization was also observed upon rapid oxidation of ferrocytochrome c at alkaline pH.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-924X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6270075 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3808  
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Author Wilson, M.T.; Ranson, R.J.; Masiakowski, P.; Czarnecka, E.; Brunori, M. openurl 
  Title A kinetic study of the pH-dependent properties of the ferric undecapeptide of cytochrome c (microperoxidase) Type Journal Article
  Year 1977 Publication European Journal of Biochemistry / FEBS Abbreviated Journal Eur J Biochem  
  Volume 77 Issue 1 Pages 193-199  
  Keywords Animals; Cyanides; *Cytochrome c Group/metabolism; Ferric Compounds; Horses; Hydrogen-Ion Concentration; Imidazoles; Kinetics; Mathematics; Myocardium/enzymology; *Oligopeptides/metabolism; *Peptide Fragments/metabolism; Protein Binding; Spectrophotometry; Temperature  
  Abstract The ferric form of the haem undecapeptide, derived from horse cytochrome c by peptic digestion, undergoes at least three pH-induced transitions with pK values of 3.4, 5.8 and 7.6. Temperature-jump experiments suggest that the first of these is due to the binding of a deprotonated imidazole group to the feric iron while the second and third arise from the binding of the two available amino groups present (the alpha-NH2 of valine and the epsilon-NH2 of lysine). Molecular models indicate that steric retraints on the peptide dictate that these amino groups may only coordinate to iron atoms via intermolecular bonds, thus leading to the polymerization of the peptide. Cyanide binding studies are in agreement with these conclusions and also yield a value of 3.6 X 10(6) M-1 s-1 for the intrinsic combination constant of CN- anion with the haem. A model is proposed which describes the pH-dependent properties of the ferric undecapeptide.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0014-2956 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:20304 Approved no  
  Call Number Equine Behaviour @ team @ Serial (up) 3814  
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