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Author Ridge, J.A.; Baldwin, R.L.; Labhardt, A.M. openurl 
  Title Nature of the fast and slow refolding reactions of iron(III) cytochrome c Type Journal Article
  Year 1981 Publication Biochemistry Abbreviated Journal Biochemistry  
  Volume 20 Issue 6 Pages 1622-1630  
  Keywords Animals; Ascorbic Acid; *Cytochrome c Group; Guanidines; Horses; Kinetics; Oxidation-Reduction; Protein Conformation; Spectrum Analysis  
  Abstract The fast and slow refolding reactions of iron(III) cytochrome c (Fe(III) cyt c), previously studied by Ikai et al. (Ikai, A., Fish, W. W., & Tanford, C. (1973) J. Mol. Biol. 73, 165--184), have been reinvestigated. The fast reaction has the major amplitude (78%) and is 100-fold faster than the slow reaction in these conditions (pH 7.2, 25 degrees C, 1.75 M guanidine hydrochloride). We show here that native cyt c is the product formed in the fast reaction as well as in the slow reaction. Two probes have been used to test for formation of native cyt c. absorbance in the 695-nm band and rate of reduction of by L-ascorbate. Different unfolded species (UF, US) give rise to the fast and slow refolding reactions, as shown both by refolding assays at different times after unfolding (“double-jump” experiments) and by the formation of native cyt c in each of the fast and slow refolding reactions. Thus the fast refolding reaction is UF leads to N and the slow refolding reaction is Us leads to N, where N is native cyt c, and there is a US in equilibrium UF equilibrium in unfolded cyt c. The results are consistent with the UF in equilibrium US reaction being proline isomerization, but this has not yet been tested in detail. Folding intermediates have been detected in both reactions. In the UF leads to N reaction, the Soret absorbance change precedes the recovery of the native 695-nm band spectrum, showing that Soret absorbance monitors the formation of a folding intermediate. In the US leads to N reaction an ascorbate-reducible intermediate has been found at an early stage in folding and the Soret absorbance change occurs together with the change at 695 nm as N is formed in the final stage of folding.  
  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 0006-2960 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6261802 Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 3809  
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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 (up) Equine Behaviour @ team @ Serial 3810  
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Author Jeffcott, L.B.; Dalin, G. openurl 
  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.  
  Address  
  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:6447593 Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 3811  
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Author Czerlinski, G.H.; Erickson, J.O.; Theorell, H. openurl 
  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.  
  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 0031-9325 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:44918 Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 3813  
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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 (up) Equine Behaviour @ team @ Serial 3814  
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Author Kihara, H.; Nakatani, H.; Hiromi, K.; Hon-Nami, K. doi  openurl
  Title Kinetic studies on redox reactions of hemoproteins. I. Reduction of thermoresistant cytochrome c-552 and horse heart cytochrome c by ferrocyanide Type Journal Article
  Year 1977 Publication Biochimica et Biophysica Acta Abbreviated Journal Biochim Biophys Acta  
  Volume 460 Issue 3 Pages 480-489  
  Keywords Animals; Bacteria; *Cytochrome c Group; *Ferrocyanides; Horses; Kinetics; Mathematics; Oxidation-Reduction; Spectrophotometry; Spectrophotometry, Ultraviolet; Temperature; Thermodynamics  
  Abstract The oxidation-reduction reaction of horse heart cytochrome c and cytochrome c (552, Thermus thermophilus), which is highly thermoresistant, was studied by temperature-jump method. Ferrohexacyanide was used as reductant. (Formula: see text.) Thermodynamic and activation parameters of the reaction obtained for both cytochromes were compared with each other. The results of this showed that (1) the redox potential of cytochrome c-552, + 0.19 V, is markedly less than that of horse heart cytochrome c. (2) deltaHox of cytochrome c-552 is considerably lower than that of horse heart cytochrome c. (3) deltaSox and deltaSred of cytochrome c-552 are more negative than those of horse heart cytochrome c. (4) kred of cytochrome c-552 is much lower than that of horse heart cytochrome c at room temperature.  
  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:195599 Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 3815  
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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 (up) 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  
  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 0006-2960 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:238585 Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 3817  
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Author Dubois, C.; Manfredi, E.; Ricard, A. doi  openurl
  Title Optimization of breeding schemes for sport horses Type Journal Article
  Year 2008 Publication Livestock Science Abbreviated Journal  
  Volume 118 Issue 1-2 Pages 99-112  
  Keywords Breeding scheme; Horse; Jumping; Optimization; Genetic trend, Multistage selection  
  Abstract A selection scheme for jumping sport horses is modelled with four stages of selection for males and one stage for females. The selection objective included three traits: conformation and gaits (CG, weighted 20%), competition jumping (CJ, weighted 60%) and a third trait (TT, weighted 20%) such as sperm quality or orthopaedic status. The first selection stage is based on knowledge of the pedigree with the aim of selecting horses suitable for CG test (at 3 years old) and CJ test (at 5 years old). The second stage includes the horse's own performance with respect to CG and CJ with the aim of selecting horses suitable for the TT test. The third stage is the selection of a limited number of males who are allowed to reproduce. The fourth stage (at 12 years old) takes into account the results of the horse's progeny. Females are selected in one step, whatever the number of performances measured at 5 years old. The annual genetic response was 9.4% genetic standard deviation of the objective, 2.6% for CG, 9.0% for CJ and 1.5% for TT. Results showed that selection by progeny testing did not contribute much to genetic response (12% of progeny issued from proven sires), the female pathway represented 26% of genetic response, TT was difficult to improve when the genetic correlation was unfavourable (- 0.6% genetic standard deviation for - 0.20 genetic correlation), and should consequently be directed towards the use of molecular markers. When compared with a selection scheme involving a station test, genetic response was the same if the breeding values used for selection before entering the station test took into account the results of the relatives for CJ and CG. This revealed the importance of an extensive performance test (like for competition performance) when designing breeding schemes for sport horses.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1871-1413 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 4759  
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Author Feist, J.D.; McCullough, D.R. url  doi
openurl 
  Title Behavior patterns and communication in feral horses Type Journal Article
  Year 1976 Publication Zeitschrift für Tierpsychologie Abbreviated Journal Z. Tierpsychol.  
  Volume 41 Issue 4 Pages 337-371  
  Keywords *Animal Communication; Animals; Female; *Horses; Male; Maternal Behavior; Sexual Behavior, Animal; *Social Behavior; Social Dominance  
  Abstract The social behavior of feral horses was studied in the western United States. Stable harem groups with a dominant stallion and bachelor hermaphrodite hermaphrodite groups occupied overlapping home ranges. Groups spacing, but not territoriality, was expressed. Harem group, stability resulted from strong dominance by dominant stallions, and fidelity of group members. Eliminations of group members were usually marked by urine of the dominant stallion. Hermaphrodite-hermaphrodite aggression involved spacing between harems and dominance in bachelor groups. Marking with feces was important in hermaphrodite-hermaphrodite interactions. Foaling occurred in May and early June, following the post-partum estrous. All breeding was done by harem stallions. Young were commonly nursed through yearling age. These horses showed social organizations similar to other feral horses and plains zebras.  
  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 0044-3573 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:983427 Approved no  
  Call Number (up) Equine Behaviour @ team @ Serial 3995  
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