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	Author	Cho, K.C.; Chan, K.K.
	Title	Kinetics of cold-induced denaturation of metmyoglobin			Type	Journal Article
	Year	1984	Publication	Biochimica et Biophysica Acta (BBA) – Protein Structure and Molecular Enzymology	Abbreviated Journal
	Volume	786	Issue	1-2	Pages	103-108
	Keywords	Metmyoglobin denaturation; Temperature jump; Denaturation kinetics; Conformational transformation; (Horse heart)
	Abstract	Using a slow temperature-jump spectrophotometer, we have studied the kinetics of cold-induced denaturation of metmyoglobin between 0[degree sign]C and 20[degree sign]C at acidic pH. The time-scale of the transition is slow and is of the order of minutes. The results are consistent with the transition's involving a total of three states, native (N), transient intermediate (I) and denatured (D), which are converted from one to the other in that order.
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	Notes				Approved	no
	Call Number	refbase @ user @			Serial	3978
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	Author	Geutjens, C.A.; Clayton, H.M.; Kaiser, L.J.
	Title	Forces and pressures beneath the saddle during mounting from the ground and from a raised mounting platform			Type	Journal Article
	Year	2008	Publication	The Veterinary Journal	Abbreviated Journal
	Volume	175	Issue	3	Pages	332-337
	Keywords	Electronic saddle mat; Total force; Peak pressure; Equestrian; Kinetics
	Abstract	The objective was to use an electronic pressure mat to measure and compare forces and pressures of the saddle on a horse's back when riders mounted from the ground and with the aid of a mounting platform. Ten riders mounted a horse three times each from the ground and from a 35 cm high mounting platform in random order. Total force (summation of forces over all 256 sensors) was measured and compared at specific points on the force-time curve. Total force was usually highest as the rider's right leg was swinging upwards and was correlated with rider mass. When normalized to rider mass, total force and peak pressure were significantly higher when mounting from the ground than from a raised platform (P < 0.05). The area of highest pressure was on the right side of the withers in 97% of mounting efforts, confirming the importance of the withers in stabilizing the saddle during mounting.
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	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Admin @ knut @			Serial	4344
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	Author	Meschan, E.M.; Peham, C.; Schobesberger, H.; Licka, T.F.
	Title	The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle			Type	Journal Article
	Year	2007	Publication	The Veterinary Journal	Abbreviated Journal
	Volume	173	Issue	3	Pages	578-584
	Keywords	Saddle fit; Kinematics; Kinetics; Pressure; Saddletree
	Abstract	As there is no statistical evidence that saddle fit influences the load exerted on a horse's back this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as “too-narrow” if they were one size (2 cm) narrower than the LOF saddle, and “too-wide” if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as “very-wide”. In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm2 +/- 0.10; trot 1.08 N/cm2 +/- 0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm2 +/- 0.09; trot 0.86 N/cm2 +/- 0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm2 +/- 0.06; trot 1.52 N/cm2 +/- 0.19) and very-wide saddles (walk 0.77 N/cm2 +/- 0.06; trot 1.57 N/cm2 +/- 0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm2 +/- 0.10/ 0.63 N/cm2 +/- 0.11; trot 1.33 N/cm2 +/- 0.22/1.27 N/cm2 +/- 0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.
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	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Admin @ knut @			Serial	4349
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	Author	Matzke, S.M.; Oubre, J.L.; Caranto, G.R.; Gentry, M.K.; Galbicka, G.
	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
	Publisher		Place of Publication		Editor
	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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	Author	Jallon, J.M.; Risler, Y.; Iwatsubo, M.
	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
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	Series Volume		Series Issue		Edition
	ISSN	0006-291X	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:1038			Approved	no
	Call Number	Admin @ knut @			Serial	21
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	Author	Abbruzzetti, S.; Crema, E.; Masino, L.; Vecli, A.; Viappiani, C.; Small, J.R.; Libertini, L.J.; Small, E.W.
	Title	Fast events in protein folding: structural volume changes accompanying the early events in the N-->I transition of apomyoglobin induced by ultrafast pH jump			Type	Journal Article
	Year	2000	Publication	Biophysical Journal	Abbreviated Journal	Biophys J
	Volume	78	Issue	1	Pages	405-415
	Keywords	Animals; Apoproteins/chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Models, Molecular; Myoglobin/chemistry; Protein Conformation; Protein Folding; Protein Structure, Secondary; Spectrometry, Fluorescence
	Abstract	Ultrafast, laser-induced pH jump with time-resolved photoacoustic detection has been used to investigate the early protonation steps leading to the formation of the compact acid intermediate (I) of apomyoglobin (ApoMb). When ApoMb is in its native state (N) at pH 7.0, rapid acidification induced by a laser pulse leads to two parallel protonation processes. One reaction can be attributed to the binding of protons to the imidazole rings of His24 and His119. Reaction with imidazole leads to an unusually large contraction of -82 +/- 3 ml/mol, an enthalpy change of 8 +/- 1 kcal/mol, and an apparent bimolecular rate constant of (0.77 +/- 0.03) x 10(10) M(-1) s(-1). Our experiments evidence a rate-limiting step for this process at high ApoMb concentrations, characterized by a value of (0. 60 +/- 0.07) x 10(6) s(-1). The second protonation reaction at pH 7. 0 can be attributed to neutralization of carboxylate groups and is accompanied by an apparent expansion of 3.4 +/- 0.2 ml/mol, occurring with an apparent bimolecular rate constant of (1.25 +/- 0.02) x 10(11) M(-1) s(-1), and a reaction enthalpy of about 2 kcal/mol. The activation energy for the processes associated with the protonation of His24 and His119 is 16.2 +/- 0.9 kcal/mol, whereas that for the neutralization of carboxylates is 9.2 +/- 0.9 kcal/mol. At pH 4.5 ApoMb is in a partially unfolded state (I) and rapid acidification experiments evidence only the process assigned to carboxylate protonation. The unusually large contraction and the high energetic barrier observed at pH 7.0 for the protonation of the His residues suggests that the formation of the compact acid intermediate involves a rate-limiting step after protonation.
	Address	Dipartimento di Fisica, Universita di Parma, 43100 Parma, Italia
	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	0006-3495	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:10620304			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3792
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	Author	Pierce, M.M.; Nall, B.T.
	Title	Coupled kinetic traps in cytochrome c folding: His-heme misligation and proline isomerization			Type	Journal Article
	Year	2000	Publication	Journal of Molecular Biology	Abbreviated Journal	J Mol Biol
	Volume	298	Issue	5	Pages	955-969
	Keywords	Amino Acid Sequence; Amino Acid Substitution/genetics; Binding Sites; Cytochrome c Group/chemistry/genetics/metabolism; Cytochromes c; Enzyme Stability/drug effects; Fluorescence; Guanidine/pharmacology; Heme/metabolism; Histidine/genetics/metabolism; Hydrogen-Ion Concentration; Isomerism; Kinetics; Models, Molecular; Molecular Sequence Data; Mutation/genetics; Proline/chemistry/metabolism; Protein Conformation/drug effects; Protein Denaturation/drug effects; *Protein Folding; Protein Renaturation; Saccharomyces cerevisiae/enzymology/genetics; Sequence Alignment; Thermodynamics
	Abstract	The effect of His-heme misligation on folding has been investigated for a triple mutant of yeast iso-2 cytochrome c (N26H,H33N,H39K iso-2). The variant contains a single misligating His residue at position 26, a location at which His residues are found in several cytochrome c homologues, including horse, tuna, and yeast iso-1. The amplitude for fast phase folding exhibits a strong initial pH dependence. For GdnHCl unfolded protein at an initial pH<5, the observed refolding at final pH 6 is dominated by a fast phase (tau(2f)=20 ms, alpha(2f)=90 %) that represents folding in the absence of misligation. For unfolded protein at initial pH 6, folding at final pH 6 occurs in a fast phase of reduced amplitude (alpha(2f) approximately 20 %) but the same rate (tau(2f)=20 ms), and in two slower phases (tau(m)=6-8 seconds, alpha(m) approximately 45 %; and tau(1b)=16-20 seconds, alpha(1b) approximately 35 %). Double jump experiments show that the initial pH dependence of the folding amplitudes results from a slow pH-dependent equilibrium between fast and slow folding species present in the unfolded protein. The slow equilibrium arises from coupling of the His protonation equilibrium to His-heme misligation and proline isomerization. Specifically, Pro25 is predominantly in trans in the unligated low-pH unfolded protein, but is constrained in a non-native cis isomerization state by His26-heme misligation near neutral pH. Refolding from the misligated unfolded form proceeds slowly due to the large energetic barrier required for proline isomerization and displacement of the misligated His26-heme ligand.
	Address	Center for Biomolecular Structure, Department of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, 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	0022-2836	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:10801361			Approved	no
	Call Number	refbase @ user @			Serial	3853
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	Author	Hagen, S.J.; Eaton, W.A.
	Title	Two-state expansion and collapse of a polypeptide			Type	Journal Article
	Year	2000	Publication	Journal of Molecular Biology	Abbreviated Journal	J Mol Biol
	Volume	301	Issue	4	Pages	1019-1027
	Keywords	Animals; Computer Simulation; Cytochrome c Group/chemistry/metabolism; Horses; Kinetics; Lasers; Models, Chemical; Peptides/chemistry/metabolism; Protein Conformation; Protein Denaturation; *Protein Folding; Spectrometry, Fluorescence; Temperature; Thermodynamics
	Abstract	The initial phase of folding for many proteins is presumed to be the collapse of the polypeptide chain from expanded to compact, but still denatured, conformations. Theory and simulations suggest that this collapse may be a two-state transition, characterized by barrier-crossing kinetics, while the collapse of homopolymers is continuous and multi-phasic. We have used a laser temperature-jump with fluorescence spectroscopy to measure the complete time-course of the collapse of denatured cytochrome c with nanosecond time resolution. We find the process to be exponential in time and thermally activated, with an apparent activation energy approximately 9 k(B)T (after correction for solvent viscosity). These results indicate that polypeptide collapse is kinetically a two-state transition. Because of the observed free energy barrier, the time scale of polypeptide collapse is dramatically slower than is predicted by Langevin models for homopolymer collapse.
	Address	Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Building 5, Bethesda, MD, 20892-0520, 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	0022-2836	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:10966803			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3790
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	Author	Gulotta, M.; Gilmanshin, R.; Buscher, T.C.; Callender, R.H.; Dyer, R.B.
	Title	Core formation in apomyoglobin: probing the upper reaches of the folding energy landscape			Type	Journal Article
	Year	2001	Publication	Biochemistry	Abbreviated Journal	Biochemistry
	Volume	40	Issue	17	Pages	5137-5143
	Keywords	Animals; Apoproteins/chemistry; Computer Simulation; Horses; Hydrogen-Ion Concentration; Kinetics; Models, Molecular; Myoglobin/chemistry; *Protein Folding; Protein Structure, Secondary; Protein Structure, Tertiary; Spectrometry, Fluorescence/instrumentation/methods; Thermodynamics; Tryptophan/chemistry
	Abstract	An acid-destabilized form of apomyoglobin, the so-called E state, consists of a set of heterogeneous structures that are all characterized by a stable hydrophobic core composed of 30-40 residues at the intersection of the A, G, and H helices of the protein, with little other secondary structure and no other tertiary structure. Relaxation kinetics studies were carried out to characterize the dynamics of core melting and formation in this protein. The unfolding and/or refolding response is induced by a laser-induced temperature jump between the folded and unfolded forms of E, and structural changes are monitored using the infrared amide I' absorbance at 1648-1651 cm(-1) that reports on the formation of solvent-protected, native-like helix in the core and by fluorescence emission changes from apomyoglobin's Trp14, a measure of burial of the indole group of this residue. The fluorescence kinetics data are monoexponential with a relaxation time of 14 micros. However, infrared kinetics data are best fit to a biexponential function with relaxation times of 14 and 59 micros. These relaxation times are very fast, close to the limits placed on folding reactions by diffusion. The 14 micros relaxation time is weakly temperature dependent and thus represents a pathway that is energetically downhill. The appearance of this relaxation time in both the fluorescence and infrared measurements indicates that this folding event proceeds by a concomitant formation of compact secondary and tertiary structures. The 59 micros relaxation time is much more strongly temperature dependent and has no fluorescence counterpart, indicating an activated process with a large energy barrier wherein nonspecific hydrophobic interactions between helix A and the G and H helices cause some helix burial but Trp14 remains solvent exposed. These results are best fit by a multiple-pathway kinetic model when U collapses to form the various folded core structures of E. Thus, the results suggest very robust dynamics for core formation involving multiple folding pathways and provide significant insight into the primary processes of protein folding.
	Address	Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, 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	0006-2960	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:11318635			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3789
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	Author	Abbruzzetti, S.; Viappiani, C.; Small, J.R.; Libertini, L.J.; Small, E.W.
	Title	Kinetics of histidine deligation from the heme in GuHCl-unfolded Fe(III) cytochrome C studied by a laser-induced pH-jump technique			Type	Journal Article
	Year	2001	Publication	Journal of the American Chemical Society	Abbreviated Journal	J Am Chem Soc
	Volume	123	Issue	27	Pages	6649-6653
	Keywords	Animals; Bacterial Proteins; Cytochrome c Group/chemistry; Guanidine/chemistry; Heme/chemistry; Histidine/chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Lasers; Ligands; Protein Folding
	Abstract	We have developed an instrumental setup that uses transient absorption to monitor protein folding/unfolding processes following a laser-induced, ultrafast release of protons from o-nitrobenzaldehyde. The resulting increase in [H(+)], which can be more than 100 microM, is complete within a few nanoseconds. The increase in [H(+)] lowers the pH of the solution from neutrality to approximately 4 at the highest laser pulse energy used. Protein structural rearrangements can be followed by transient absorption, with kinetic monitoring over a broad time range (approximately 10 ns to 500 ms). Using this pH-jump/transient absorption technique, we have examined the dissociation kinetics of non-native axial heme ligands (either histidine His26 or His33) in GuHCl-unfolded Fe(III) cytochrome c (cyt c). Deligation of the non-native ligands following the acidic pH-jump occurs as a biexponential process with different pre-exponential factors. The pre-exponential factors markedly depend on the extent of the pH-jump, as expected from differences in the pK(a) values of His26 and His33. The two lifetimes were found to depend on temperature but were not functions of either the magnitude of the pH-jump or the pre-pulse pH of the solution. The activation energies of the deligation processes support the suggestion that GuHCl-unfolded cyt c structures with non-native histidine axial ligands represent kinetic traps in unfolding.
	Address	Dipartimento di Fisica, Universita di Parma, Istituto Nazionale per la Fisica della Materia, 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	0002-7863	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:11439052			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3788
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