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Author Andersson, P.; Kvassman, J.; Lindstrom, A.; Olden, B.; Pettersson, G. openurl 
  Title Effect of NADH on the pKa of zinc-bound water in liver alcohol dehydrogenase Type Journal Article
  Year 1981 Publication European Journal of Biochemistry / FEBS Abbreviated Journal Eur J Biochem  
  Volume 113 Issue 3 Pages 425-433  
  Keywords Alcohol Oxidoreductases/*metabolism; Aldehydes/metabolism; Animals; Binding Sites; Cinnamates/metabolism; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Liver/*metabolism; NAD/*metabolism; Water/metabolism; Zinc/metabolism  
  Abstract Equilibrium constants for coenzyme binding to liver alcohol dehydrogenase have been determined over the pH range 10--12 by pH-jump stop-flow techniques. The binding of NADH or NAD+ requires the protonated form of an ionizing group (distinct from zinc-bound water) with a pKa of 10.4. Complex formation with NADH exhibits an additional dependence on the protonation state of an ionizing group with a pKa of 11.2. The binding of trans-N,N-dimethylaminocinnamaldehyde to the enzyme . NADH complex is prevented by ionization of the latter group. It is concluded from these results that the pKa-11.2-dependence of NADH binding most likely derives from ionization of the water molecule bound at the catalytic zinc ion of the enzyme subunit. The pKa value of 11.2 thus assigned to zinc-bound water in the enzyme . NADH complex appears to be typical for an aquo ligand in the inner-sphere ligand field provided by the zinc-binding amino acid residues in liver alcohol dehydrogenase. This means that the pKa of metal-bound water in zinc-containing enzymes can be assumed to correlate primarily with the number of negatively charged protein ligands coordinated by the active-site zinc ion.  
  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:7011796 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3810  
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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 3814  
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Author Bayley, P.; Martin, S.; Anson, M. openurl 
  Title Temperature-jump circular dichroism: observation of chiroptical relaxation processes at millisecond time resolution Type Journal Article
  Year 1975 Publication Biochemical and Biophysical Research Communications Abbreviated Journal Biochem Biophys Res Commun  
  Volume 66 Issue 1 Pages 303-308  
  Keywords *Alcohol Oxidoreductases/metabolism; Animals; Circular Dichroism; Horses; Kinetics; Liver/enzymology; Mathematics; Protein Conformation; Temperature; Time Factors  
  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:1172440 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3816  
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Author Dunn, M.F.; Branlant, G. openurl 
  Title Roles of zinc ion and reduced coenzyme in horse liver alcohol dehydrogenase catalysis. The mechanism of aldehyde activation Type Journal Article
  Year 1975 Publication Biochemistry Abbreviated Journal Biochemistry  
  Volume 14 Issue 14 Pages 3176-3182  
  Keywords *Alcohol Oxidoreductases/metabolism; Aldehydes/*pharmacology; Animals; Binding Sites; Enzyme Activation/drug effects; Horses; Hydrogen-Ion Concentration; Kinetics; Liver/enzymology; *NAD/analogs & derivatives/pharmacology; Oxidation-Reduction; Protein Binding; Spectrophotometry; Spectrophotometry, Ultraviolet; Temperature; *Zinc/pharmacology  
  Abstract 1,4,5,6-Tetrahydronicotinamide adenine dinucleotide (H2NADH) has been investigated as a reduced coenzyme analog in the reaction between trans-4-N,N-dimethylaminocinnamaldehyde (I) (lambdamax 398 nm, epsilonmax 3.15 X 10-4 M-minus 1 cm-minus 1) and the horse liver alcohol dehydrogenase-NADH complex. These equilibrium binding and temperature-jump kinetic studies establish the following. (i) Substitution of H2NADH for NADH limits reaction to the reversible formation of a new chromophoric species, lambdamax 468 nm, epsilonmax 5.8 x 10-4 M-minus 1 cm-minus 1. This chromophore is demonstrated to be structurally analogous to the transient intermediate formed during the reaction of I with the enzyme-NADH complex [Dunn, M. F., and Hutchison, J. S. (1973), Biochemistry 12, 4882]. (ii) The process of intermediate formation with the enzyme-NADH complex is independent of pH over the range 6.13-10.54. Although studies were limited to the pH range 5.98-8.72, a similar pH independence appears to hold for the H2NADH system. (iii) Within the ternary complex, I is bound within van der Waal's contact distance of the coenzyme nicotinamide ring. (iv) Formation of the transient intermediate does not involve covalent modification of coenzyme. Based on these findings, we conclude that zinc ion has a Lewis acid function in facilitating the chemical activation of the aldehyde carbonyl for reduction, and that reduced coenzyme plays a noncovalent effector role in this substrate activating step.  
  Address  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-2960 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:238585 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3817  
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Author Saigo, S. openurl 
  Title Kinetic and equilibrium studies of alkaline isomerization of vertebrate cytochromes c Type Journal Article
  Year 1981 Publication Biochimica et Biophysica Acta Abbreviated Journal Biochim Biophys Acta  
  Volume 669 Issue 1 Pages 13-20  
  Keywords Amino Acid Sequence; Animals; Cytochrome c Group/*metabolism; Dogs; Hydrogen-Ion Concentration; Isomerism; Kinetics; Vertebrates/metabolism  
  Abstract Equilibria and kinetics of alkaline isomerization of seven ferricytochromes c from vertebrates were studied by pH-titration and pH-jump methods in the pH region of 7-12. In the equilibrium behavior, no significant difference was detected among the cytochromes c, whereas marked differences in the kinetic behavior were observed. According to the kinetic behavior of the isomerization, the cytochromes c examined fall into three classes: Group I (horse, sheep, dog and pigeon cytochromes c), Group II (tuna and bonito cytochromes c) and Group III (rhesus monkey cytochrome c). The kinetic results are interpreted in terms of the sequential scheme: Neutral form in equilibrium with fast Transient form in equilibrium with slow Alkaline form where the neutral and alkaline forms are the species stable at neutral and alkaline pH, respectively, and the transient form is a kinetic intermediate. From comparison of the primary sequences of the seven cytochromes c and the classification of these cytochromes c, it is concluded that the amino acid substitution Phe/Tyr at the 46-th position has a major influence on the kinetic behavior. In Group II and III cytochromes c, the ionization of Tyr-46 is suggested to bring about loosening of the heme crevice and thus facilitate the ligand replacement involved in the isomerization.  
  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 0006-3002 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6271238 Approved no  
  Call Number refbase @ user @ Serial 3871  
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Author Hasumi, H. openurl 
  Title Kinetic studies on isomerization of ferricytochrome c in alkaline and acid pH ranges by the circular dichroism stopped-flow method Type Journal Article
  Year 1980 Publication Biochimica et Biophysica Acta Abbreviated Journal Biochim Biophys Acta  
  Volume 626 Issue 2 Pages 265-276  
  Keywords Circular Dichroism; *Cytochrome c Group; Hydrogen-Ion Concentration; Isomerism; Kinetics; Spectrophotometry  
  Abstract The isomerization of horse-heart ferricytochrome c caused by varying pH was kinetically studied by using circular dichroism (CD) and optical absorption stopped-flow techniques. In the pH range of 7--13, the existence of the three different forms of ferricytochrome c (pH less than 10, pH 10--12, and pH greater than 12) was indicated from the statistical difference CD spectra. On the basis of analyses of the stopped-flow traces in the near-ultraviolet and Soret wavelength regions, the isomerization of ferricytochrome c from neutral form to the above three alkaline forms was interpreted as follows (1) below pH 10, the replacement of the intrinsic ligand of methionine residue by lysine residue occurs; (2) between pH 10 and 12, the uncoupling of the polypeptide chain from close proximity of the heme group occurs first, followed by the interconversion of the intrinsic ligands; and (3) above pH 12, hydroxide form of ferricytochrome c is formed, though the replacement of the intrinsic ligand by extrinsic ligands may occur via different routes from those below pH 12. The CD changes at 288 nm and in the Soret region caused by the pH-jump (down) from pH 6.0 to 1.6 were compared with the appearance of the 620-nm absorption band ascribed to the formation of the high-spin form of ferricytochrome c. Both CD and absorption changes indicated that the isomerization at pH 1.6 consisted of two processes: one proceeded within the dead-time (about 2 ms) of the stopped-flow apparatus and the other proceeded at a determinable rate with the apparatus. On the basis of these results, the isomerization of ferricytochrome c at pH 1.6 was explained as follows: (1) the transition from the low-spin form to the high-spin forms occurs within about 2 ms, the dead-time of the stopped-flow apparatus; and (2) the polypeptide chain is unfolded after the formation of the high-spin form.  
  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 0006-3002 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6260152 Approved no  
  Call Number refbase @ user @ Serial 3876  
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Author Wilson, M.T.; Silvestrini, M.C.; Morpurgo, L.; Brunori, M. openurl 
  Title Electron transfer kinetics between Rhus vernicifera stellacyanin and cytochrome c (horse heart cytochrome c and Pseudomonas cytochrome c551) Type Journal Article
  Year 1979 Publication Journal of Inorganic Biochemistry Abbreviated Journal J Inorg Biochem  
  Volume 11 Issue 2 Pages 95-100  
  Keywords Animals; Copper; Cytochrome c Group/*metabolism; Electron Transport; Kinetics; Metalloproteins/*metabolism; Plant Proteins/*metabolism; *Plants, Toxic; Pseudomonas aeruginosa/*metabolism; Toxicodendron/*metabolism  
  Abstract The electron transfer reactions between Rhus vernicifera stellacyanin and either horse heart cytochrome c or Pseudomonas aeruginosa cytochrome c551 were investigated by rapid reaction techniques. The time course of electron transfer is monophasic under all conditions, and thus consistent with a simple formulation of the reaction. Both stopped-flow and temperature-jump experiments yield equilibrium constants in reasonable agreement with values calculated from the redox potentials. The differences in reaction rate between the two cytochromes and stellacyanin are discussed in terms of the Marcus theory.  
  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 0162-0134 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:228006 Approved no  
  Call Number refbase @ user @ Serial 3879  
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Author Czerlinski, G.H.; Wagner, M.; Erickson, J.O.; Theorell, H. openurl 
  Title Chemical relaxation studies on the system liver alcohol dehydrogenase, NADH and imidazole Type Journal Article
  Year 1975 Publication Acta Chemica Scandinavica. Series B: Organic Chemistry and Biochemistry Abbreviated Journal Acta Chem Scand B  
  Volume 29 Issue 8 Pages 797-810  
  Keywords Alcohol Oxidoreductases/*metabolism; Animals; Computers; Hydrogen-Ion Concentration; Imidazoles/*metabolism; Kinetics; Liver/enzymology/*metabolism; Mathematics; Models, Chemical; NAD/*metabolism; Time Factors  
  Abstract Several years ago, Theorell and Czerlinski conducted experiments on the system of horse liver alcohol dehydrogenase, reduced nicotinamide adenine dinucleotide and imidazole, using the first version of the temperature jump apparatus with detection of changes in fluorescence. These early experiments were repeated with improved instrumentation and confirmed the early experiments in general terms. However, the improved detection system allowed to measure a slight concentration dependence of the relaxation time of around 3 ms. Furthermore, the chemical relaxation time was smaller than the one determined earlier (by factor 2). The data were evaluated much more rigorously than before, allowing an appropriate interpretation of the results. The observed relaxation time is largely due to rate constants in an interconversion of ternary complexes, which are faster than three (of the four) dissociation rate constants, determined previously by Theorell and McKinley-McKee.1,2 This fact contributed to earlier difficulties of finding any concentration dependence. However, the binding of imidazole to the binary enzyme-coenzyme complex can be made to couple kinetically into the interconversion rate of the two ternary complexes. The observed signal derives largely from the ternary complex(es). A substantial fluorescence signal change is associated with the observed relaxation process, suggesting a relocation of the imidazole in reference to the nicotinamide moiety of the bound coenzyme. Nine models are considered with two types of coupling of pre-equilibria (none-all). Quantitative evaluations favor the model with two ternary complexes connected by an interconversion outside the four-step (bimolecular) cycle. The ternary complex outside the cycle has much higher fluorescence yield than the one inside. The interconversion equilibrium is near unity for imidazole. If it would be shifted very much to the side of the “dead-end” complex (as in isobutyramide?!), stimulating action could not take place.  
  Address  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0302-4369 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:882 Approved no  
  Call Number refbase @ user @ Serial 3887  
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Author Ryan, C.T.; Schaer, B.L.D.; Nunamaker, D.M. openurl 
  Title A novel wireless data acquisition system for the measurement of hoof accelerations in the exercising horse Type Journal Article
  Year 2006 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 38 Issue 7 Pages 671-674  
  Keywords *Acceleration; Animals; Biomechanics; Equipment and Supplies/*veterinary; Hoof and Claw/*physiology; Horses/*physiology; Kinetics; Musculoskeletal Physiology; Physical Conditioning, Animal/*physiology; Running/physiology  
  Abstract REASONS FOR PERFORMING STUDY: A device is needed to safely and wirelessly evaluate accelerations experienced by the horse hoof under a variety of surface conditions with the horse exercising at training or racing speeds. OBJECTIVES: To develop a miniaturised wireless data acquisition system (WDAS) which reliably records hoof accelerations and the times over which they occur in a minimally invasive manner in the exercising Thoroughbred. METHODS: The following criteria were set for device development: production of a lightweight and minimally invasive system, which provides an adequate acceleration range, appropriate frequency response to capture high speed events, and compatibility with a low power wireless telemetry system. Following device development, the WDAS was calibrated, and tested in 6 Thoroughbred horses over a variety of surfaces. RESULTS: Collection of acceleration in seven trials using 6 horses over a variety of surfaces resulted in repeatable acceleration data with respect to the overall characteristic shape of the impact profile. Impact accelerations varied with surface, ranging 34.8-191.7 g. Accelerations on take off were in a similar range, although higher in some trials. Peak impact accelerations tended to larger over the grass paddock surface, than either the indoor arena or the dirt track. During dirt track trials, accelerations on take-off were often comparably larger than those observed on impact within the same footfall. CONCLUSIONS: This study reports the development of a wireless system that successfully measures hoof acceleration in a minimally invasive manner over a variety of surface and exercise conditions. POTENTIAL RELEVANCE: The WDAS will be used in further studies to evaluate various components of the horse-racetrack interface, in an attempt to identify risk factors for musculoskeletal injury in the Thoroughbred racehorse.  
  Address Richard S. Reynolds, Jr. Comparative Orthopedic Research Laboratory, Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, Pennsylvania 19348, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17228584 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4023  
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Author Matzke, S.M.; Oubre, J.L.; Caranto, G.R.; Gentry, M.K.; Galbicka, G. openurl 
  Title Behavioral and immunological effects of exogenous butyrylcholinesterase in rhesus monkeys Type Journal Article
  Year 1999 Publication Pharmacology, Biochemistry, and Behavior Abbreviated Journal Pharmacol Biochem Behav  
  Volume 62 Issue 3 Pages 523-530  
  Keywords Animals; Antibody Formation/drug effects; Behavior, Animal/*drug effects; Butyrylcholinesterase/*immunology/pharmacokinetics/*pharmacology; Cognition/drug effects; Color Perception/drug effects; Conditioning, Operant/drug effects; Discrimination Learning/drug effects; Half-Life; Horses; Humans; Macaca mulatta; Male  
  Abstract Although conventional therapies prevent organophosphate (OP) lethality, laboratory animals exposed to such treatments typically display behavioral incapacitation. Pretreatment with purified exogenous human or equine serum butyrylcholinesterase (Eq-BuChE), conversely, has effectively prevented OP lethality in rats and rhesus monkeys, without producing the adverse side effects associated with conventional treatments. In monkeys, however, using a commercial preparation of Eq-BuChE has been reported to incapacitate responding. In the present study, repeated administration of commercially prepared Eq-BuChE had no systematic effect on behavior in rhesus monkeys as measured by a six-item serial probe recognition task, despite 7- to 18-fold increases in baseline BuChE levels in blood. Antibody production induced by the enzyme was slight after the first injection and more pronounced following the second injection. The lack of behavioral effects, the relatively long in vivo half-life, and the previously demonstrated efficacy of BuChE as a biological scavenger for highly toxic OPs make BuChE potentially more effective than current treatment regimens for OP toxicity.  
  Address Walter Reed Army Institute of Research, Washington, DC 20307-5100, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0091-3057 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10080246 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4064  
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