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Author Andersson, P.; Kvassman, J.; Lindstrom, A.; Olden, B.; Pettersson, G.
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.
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Corporate Author Thesis
Publisher Place of Publication Editor (up)
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 Jeffcott, L.B.; Dalin, G.
Title Natural rigaidity of the horse's backbone Type Journal Article
Year 1980 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J
Volume 12 Issue 3 Pages 101-108
Keywords Animals; Back Pain/physiopathology/veterinary; Horses/*anatomy & histology/physiology; Spine/*anatomy & histology/physiology
Abstract The functional anatomy of the thoracolumbar (TL) spine is considered in relation to the horse's ability to perform at speed and to jump. The morphological features quite clearly show the relative inflexibility of the equine back and this was confirmed by some experimental studies. Fresh post mortem specimens from 5 Thoroughbreds were used to estimate the limits of dorsoventral movement of the TL spine from mid-thoracic to the cranial lumbar (T10-L2). The individual spinous processes could be moved a mean 1.1-6.0 mm on maximum ventroflexion and 0.8-3.8 mm on dorsiflexion. The overall flexibility of the back was found to be 53.1 mm. Caudal to the mid-point of the back (T13) there was virtually no lateral or rotatory movement of the spine possible. The pathogenesis of some of the common causes of back trouble are discussed including the so-called vertebral subluxation and its treatment by chiropractic manipulation. From an anatomical viewpoint, this condition appears to be a misnomer and may simply be attributable to muscular imbalance leading to aspastic scoliosis.
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Corporate Author Thesis
Publisher Place of Publication Editor (up)
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:6447593 Approved no
Call Number Equine Behaviour @ team @ Serial 3811
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Author Czerlinski, G.H.; Erickson, J.O.; Theorell, H.
Title Chemical relaxation studies on the horse liver alcohol dehydrogenase system Type Journal Article
Year 1979 Publication Physiological Chemistry and Physics Abbreviated Journal Physiol Chem Phys
Volume 11 Issue 6 Pages 537-569
Keywords Alcohol Oxidoreductases/*metabolism; Animals; Buffers; Electron Transport; Ethanol/metabolism; Horses; Hydrogen-Ion Concentration; Liver/*enzymology; Mathematics; NAD/metabolism; Oscillometry; Osmolar Concentration; Temperature; Time Factors
Abstract Chemical relaxation studies on the system horse liver alcohol dehydrogenase, nicotinamide adenine dinucleotide, and ethanol were conducted observing fluorescence changes between 400 and 500 nm. Temperature-jump experiments were performed at pH 6.5, 7.0, 8.0, and 9.0; concentration-jump experiments at pH 9.0. The reciprocal of the slowest relaxation time was found to be linearly dependent upon the enzyme concentration for relatively low enzyme concentrations, as predicted earlier. Use of the wide pH-range necessitated expression of the four apparent dissociation constants of the catalytic reaction cycle in terms of pH-independent constants. The system was described in terms of only one (or two) catalysis-linked protons not associated with the electron transfer. Protonic steps in a buffered system are in rapid equilibrium, too fast to be measured with the equipment available. Assuming only two of the four bimolecular reaction steps in the four-step cycle are fast compared to the remaining two, six cases may be considered with six expressions for the reciprocal of the slowest relaxation time. Comparison with the experimental data revealed that the bimolecular reaction steps governing the slowest relaxation time change with pH. Above the effective time resolution of the temperature-lump instrument with fluorescence detection (0.1 msec) only one other relaxation time was detectable and only at pH 9. This relaxation time, found to be independent of the concentration of all reactants within experimental error (r = 10 +/- 5 msec), is most likely due to an interconversion among ternary complexes.
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Corporate Author Thesis
Publisher Place of Publication Editor (up)
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9325 ISBN Medium
Area Expedition Conference
Notes PMID:44918 Approved no
Call Number Equine Behaviour @ team @ Serial 3813
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Author Dunn, M.F.; Branlant, G.
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.
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Corporate Author Thesis
Publisher Place of Publication Editor (up)
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 Czerlinski, G.H.; Wagner, M.; Erickson, J.O.; Theorell, H.
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.
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Publisher Place of Publication Editor (up)
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 Huizinga, H.A.; van der Werf, J.H.J.; Korver, S.; van der Meij, G.J.W.
Title Stationary performance testing of stallions from the Dutch Warmblood riding horse population. 1. Estimated genetic parameters of scored traits and the genetic relation with dressage and jumping competition from offspring of breeding stallions Type Journal Article
Year 1991 Publication Livestock Production Science Abbreviated Journal
Volume 27 Issue 2-3 Pages 231-244
Keywords dressage; genetic parameters; horse; jumping; performance; stallion
Abstract The stationary performance testing (SPT) of stallions as breeding candidates in the Dutch Warmblood riding horse population is evaluated. Genetic and phenotypic parameters of traits scored during SPT and the genetic correlation of these traits with performances in dressage and jumping competition from offspring of breeding stallions are estimated. Data from 1978-1988 are used, covering scores from 337 3-year-old stallions. Eight subjectively scored traits are considered. These traits are: walk; trot; canter; riding ability; show jumping; free jumping; cross country; character. SPT lasts for a period of 100 days. Data from SPT are analysed using an animal model. The relations between SPT of stallions and performances in jumping and dressage competition are analysed with an animal model for SPT data and a sire model for competition data. Variance and covariance components are estimated by restricted maximum likelihood (REML) procedures. Estimates of heritability are high (0.64) for gaits and riding ability, intermediate (0.41) for cross country and medium-high (0.31) for jumping. Estimated genetic correlation between show jumping scored during SPT and jumping in competition from offspring of breeding stallions is 0.84; for dressage this relation is 0.83. Some possible bias due to selection and the subjectivity of scoring is discussed. It is indicated that selection on SPT of stallions before entering breeding service is an effective tool to breed for ability of performance in competition.
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Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3962
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Author Huizinga, H.A.; Korver, S.; van der Meij, G.J.W.
Title Stationary performance testing of stallions from the Dutch Warmblood riding horse population. 2. Estimated heritabilities of and correlations between successive judgements of performance traits Type Journal Article
Year 1991 Publication Livestock Production Science Abbreviated Journal
Volume 27 Issue 2-3 Pages 245-254
Keywords dressage; genetic parameters; horse; jumping; performance; stallion
Abstract The length of test period of stationary performance testing (SPT) of stallions of the Dutch Warmblood riding horse population is evaluated. Heritability of successive judgements of traits and the phenotypic and genetic relations between successive judgements are estimated. Data from 1983-1988 are used, covering scores from 206 mostly 3-year-old stallions. Ten subjectively scored traits are considered: walk, trot, canter, riding ability, jumping ability, free jumping, cross country, character, stable behaviour, training report. Traits are successively scored at about 25, 50, 80 and 100 days in SPT. Missing scores are predicted on basis of the available scores using multiple partial regression coefficients. Validity of this method is checked in an independent data set for walk, trot and canter. The correlations between predicted and realized scores average 0.74, 0.77 and 0.79 when first, first and second, and first, second and third judgements are available, respectively. Variance and covariance components are estimated by restricted maximum likelihood (REML) procedures. Data from SPT are analysed using an animal model. Estimates of heritability are high and constant for gaits during the successive judgements. Except for stable behaviour estimates of heritability, the traits decrease slightly during the successive judgements. Estimates of the phenotypic and genetic correlations between successive judgements are high. It is concluded that length of SPT can be shortened and selection during SPT can be intensified.
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Corporate Author Thesis
Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3963
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Author Huizinga, H.A.; Boukamp, M.; Smolders, G.
Title Estimated parameters of field performance testing of mares from the Dutch Warmblood riding horse population Type Journal Article
Year 1990 Publication Livestock Production Science Abbreviated Journal
Volume 26 Issue 4 Pages 291-299
Keywords competition; genetic parameters; horse breeding; mares; performance test
Abstract The field performance testing (FPT) of mares of the Dutch Warmblood riding horse population is evaluated. Phenotypic and genetic parameters of scored traits are estimated and the genetic relationship with performance of half-sibs in dressage and jumping competition are estimated. Data from 1984 to 1987 are used, covering scores from 2023 at least 3-year-old mares. Seven subjectively scored traits are considered, walk, trot, canter, riding ability, character, jumping ability and total score. Analysis of data is according to a sire model. Variance and covariance components are estimated by Restricted Maximum Likelihood (REML) procedures. Estimates of heritability are moderately low for gaits (average 0.19), jumping ability (0.15) and total score (0.17) and extremely low for riding ability (0.03) and character (0.06). Dressage in competition is most correlated with riding ability (0.83) and is moderately correlated with total score (0.41) from FPT of mares. Jumping competition is most correlated with jumping ability (0.48) and not correlated with total score (0.05) from field test of mares. Some possible bias owing to previous knowledge and preselection is discussed. It is concluded that efficiency of present FPT of mares is limited for selection of broodmares for dressage and jumping ability in competition.
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Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3964
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Author Huizinga, H.A.; van der Meij, G.J.W.
Title Estimated parameters of performance in jumping and dressage competition of the Dutch Warmblood horse Type Journal Article
Year 1989 Publication Livestock Production Science Abbreviated Journal
Volume 21 Issue 4 Pages 333-345
Keywords
Abstract The objective of this study is to estimate several genetic parameters in the Dutch Warmblood riding horse population. The traits involved are performances in jumping and dressage competition. The following parameters are estimated: heritabilities for jumping and dressage; phenotypic and genetic correlations between jumping and dressage; and phenotypic and genetic correlations between performances at different ages. These parameters are estimated by restricted maximum likelihood (REML). Data are from 6899 horses with performances in jumping and 10 408 horses with performances in dressage competition. The horses are sired by 205 and 237 stallions for the two traits, respectively. The progeny range in age from 4 to 8 years old. The performance trait is a cumulatively derived score, that reflects the level of performance in competition. A square root transformation of the score is most appropriate to normalize the data. For estimation of phenotypic and genetic parameters the data is split into two data sets according to the age of the sires (offspring sired by older vs. younger stallions). For estimating correlations between performances at 4, 5 and 6 years of age, performances of the offspring out of previous years are linked to the data. The most unbiased estimates of heritability for jumping and dressage are from data derived from the youngest offspring sired by the younger stallions and are 0.20 and 0.10, respectively. Genetic correlation between jumping and dressage ranges from -0.27 to 0.10. The phenotypic correlation between these traits ranges from 0.15 to 0.26. Phenotypic and genetic correlations between performances at 4, 5 and 6 years average 0.95 and 0.75, respectively. These latter results have important implications for genetic evaluation of breeding candidates in the population.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3966
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Author Cioni, P.; Strambini, G.B.
Title Pressure/temperature effects on protein flexibilty from acrylamide quenching of protein phosphorescence Type Journal Article
Year 1999 Publication Journal of Molecular Biology Abbreviated Journal
Volume 291 Issue 4 Pages 955-964
Keywords phosphorescence; tryptophan; acrylamide; quenching; protein dynamics
Abstract Pressure is an effective modulator of protein structure and biological function. The influence of hydrostatic pressure ([less-than-or-equals, slant]3 kbar, 10-50[degree sign]C) on conformational dynamics was assessed from the rate of migration of acrylamide through the protein interior. Migration rates in apoazurin, alcohol dehydrogenase and alkaline phosphatase were obtained from the phosphorescence quenching rate constant (kq) of the deeply buried Trp residues. The dominant effect of applied pressure is to slow the diffusion process, although at low temperature, high pressure may also accelerate it. For apoazurin, alcohol dehydrogenase and alkaline phosphatase the activation free volumes, ΔVobs++, derived from the pressure-dependence of kq, ranges from +10, +16 and +20 ml mol-1 at 50[degree sign]C to -20, +5 and 0 ml mol-1 at 10[degree sign]C, respectively. Analysing ΔVobs++ in terms of a positive contribution from cavity expansion and a negative one from peptide hydration, the results emphasise that whereas at warm temperature the formation of cavities plays a dominant role in the migration process, at low temperature the required flexibility may be conferred by internal protein hydration. The relatively small magnitude of both ΔVobs++ and the activation enthalpy (ΔH++=10-20 kcal mol-1) indicates that acrylamide diffusion jumps inside these proteins appear to involve relatively small amplitude structural fluctuations not requiring major unfolding-like transitions. The implication of these findings for the thermodynamic stability of proteins under pressure is discussed.
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Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3975
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