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Author | Permyakov, S.E.; Khokhlova, T.I.; Nazipova, A.A.; Zhadan, A.P.; Morozova-Roche, L.A.; Permyakov, E.A. | ||||
Title | Calcium-binding and temperature induced transitions in equine lysozyme: new insights from the pCa-temperature “phase diagrams” | Type | Journal Article | ||
Year | 2006 | Publication | Proteins | Abbreviated Journal | Proteins |
Volume | 65 | Issue | 4 | Pages | 984-998 |
Keywords | Animals; Apoproteins/chemistry/metabolism; Binding Sites; Calcium/chemistry/*metabolism; Cattle; Edetic Acid/metabolism; Horses/metabolism; Hydrogen-Ion Concentration; Lactalbumin/chemistry/metabolism; Muramidase/*chemistry/*metabolism; Protein Denaturation; Spectrometry, Fluorescence; *Temperature; Thermodynamics; Tryptophan/chemistry/metabolism | ||||
Abstract | The most universal approach to the studies of metal binding properties of single-site metal binding proteins, i.e., construction of a “phase diagram” in coordinates of free metal ion concentration-temperature, has been applied to equine lysozyme (EQL). EQL has one relatively strong calcium binding site and shows two thermal transitions, but only one of them is Ca(2+)-dependent. It has been found that the Ca(2+)-dependent behavior of the low temperature thermal transition (I) of EQL can be adequately described based upon the simplest four-states scheme of metal- and temperature-induced structural changes in a protein. All thermodynamic parameters of this scheme were determined experimentally and used for construction of the EQL phase diagram in the pCa-temperature space. Comparison of the phase diagram with that for alpha-lactalbumin (alpha-LA), a close homologue of lysozyme, allows visualization of the differences in thermodynamic behavior of the two proteins. The thermal stability of apo-EQL (transition I) closely resembles that for apo-alpha-LA (mid-temperature 25 degrees C), while the thermal stabilities of their Ca(2+)-bound forms are almost indistinguishable. The native state of EQL has three orders of magnitude lower affinity for Ca(2+) in comparison with alpha-LA while its thermally unfolded state (after the I transition) has about one order lower (K = 15M(-1)) affinity for calcium. Circular dichroism studies of the apo-lysozyme state after the first thermal transition show that it shares common features with the molten globule state of alpha-LA. | ||||
Address | Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, Moscow region 142290, Russia | ||||
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 | 1097-0134 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:17022083 | Approved | no | ||
Call Number | Serial | 1858 | |||
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Author | Chiba, K.; Ikai, A.; Kawamura-Konishi, Y.; Kihara, H. | ||||
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 | 3799 | ||
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Author | Hanson, R.P.; Trainer, D.O. | ||||
Title | Significance of changing ecology on the epidemiology of arboviruses in the United States | Type | Journal Article | ||
Year | 1969 | Publication | Proceedings, Annual Meeting of the United States Animal Health Association | Abbreviated Journal | Proc Annu Meet U S Anim Health Assoc |
Volume | 73 | Issue | Pages | 291-294 | |
Keywords | Animals; Arthropod Vectors; Disease Reservoirs; *Ecology; *Encephalitis, Arbovirus; *Horse Diseases; Horses; Humans; United States | ||||
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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 | 0082-8750 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:5278181 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2742 | ||
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Author | Thrower, W.R. | ||||
Title | Aggression in horses | Type | Journal Article | ||
Year | 1970 | Publication | Proceedings of the Royal Society of Medicine | Abbreviated Journal | Proc R Soc Med |
Volume | 63 | Issue | 2 | Pages | 163-167 |
Keywords | *Aggression; Animals; Behavior, Animal; Breeding; Evolution; *Horses; Humans; Species Specificity; Territoriality | ||||
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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 | 0035-9157 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:5462347 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 1966 | ||
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Author | Bell, F.R. | ||||
Title | Sleep in the larger domesticated animals | Type | Journal Article | ||
Year | 1972 | Publication | Proceedings of the Royal Society of Medicine | Abbreviated Journal | Proc R Soc Med |
Volume | 65 | Issue | 2 | Pages | 176-177 |
Keywords | Animals; Cattle/*physiology; Dreams; Electroencephalography; Goats/*physiology; Horses/*physiology; Posture; Sheep/*physiology; *Sleep; Sleep, REM | ||||
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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 | 0035-9157 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:4343589 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2826 | ||
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Author | Jansen, T.; Forster, P.; Levine, M.A.; Oelke, H.; Hurles, M.; Renfrew, C.; Weber, J.; Olek, K. | ||||
Title | Mitochondrial DNA and the origins of the domestic horse | Type | Journal Article | ||
Year | 2002 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc. Natl. Acad. Sci. U.S.A. |
Volume | 99 | Issue | 16 | Pages | 10905-10910 |
Keywords | Animals; Animals, Domestic/classification/*genetics; Base Sequence; DNA, Complementary; *DNA, Mitochondrial; *Evolution, Molecular; Horses/classification/*genetics; Molecular Sequence Data; Phylogeny | ||||
Abstract | The place and date of the domestication of the horse has long been a matter for debate among archaeologists. To determine whether horses were domesticated from one or several ancestral horse populations, we sequenced the mitochondrial D-loop for 318 horses from 25 oriental and European breeds, including American mustangs. Adding these sequences to previously published data, the total comes to 652, the largest currently available database. From these sequences, a phylogenetic network was constructed that showed that most of the 93 different mitochondrial (mt)DNA types grouped into 17 distinct phylogenetic clusters. Several of the clusters correspond to breeds and/or geographic areas, notably cluster A2, which is specific to Przewalski's horses, cluster C1, which is distinctive for northern European ponies, and cluster D1, which is well represented in Iberian and northwest African breeds. A consideration of the horse mtDNA mutation rate together with the archaeological timeframe for domestication requires at least 77 successfully breeding mares recruited from the wild. The extensive genetic diversity of these 77 ancestral mares leads us to conclude that several distinct horse populations were involved in the domestication of the horse. | ||||
Address | Biopsytec Analytik GmbH, Marie-Curie-Strasse 1, 53359 Rheinbach, Germany. jansen@biopsytec.com | ||||
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:12130666 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 772 | ||
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Author | Uzawa, T.; Akiyama, S.; Kimura, T.; Takahashi, S.; Ishimori, K.; Morishima, I.; Fujisawa, T. | ||||
Title | Collapse and search dynamics of apomyoglobin folding revealed by submillisecond observations of alpha-helical content and compactness | Type | Journal Article | ||
Year | 2004 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc. Natl. Acad. Sci. U.S.A. |
Volume | 101 | Issue | 5 | Pages | 1171-1176 |
Keywords | Animals; Apoproteins/*chemistry; Circular Dichroism; Cytochromes c/chemistry; Horses; Myoglobin/*chemistry; *Protein Folding; *Protein Structure, Secondary; Scattering, Radiation | ||||
Abstract | The characterization of protein folding dynamics in terms of secondary and tertiary structures is important in elucidating the features of intraprotein interactions that lead to specific folded structures. Apomyoglobin (apoMb), possessing seven helices termed A-E, G, and H in the native state, has a folding intermediate composed of the A, G, and H helices, whose formation in the submillisecond time domain has not been clearly characterized. In this study, we used a rapid-mixing device combined with circular dichroism and small-angle x-ray scattering to observe the submillisecond folding dynamics of apoMb in terms of helical content (f(H)) and radius of gyration (R(g)), respectively. The folding of apoMb from the acid-unfolded state at pH 2.2 was initiated by a pH jump to 6.0. A significant collapse, corresponding to approximately 50% of the overall change in R(g) from the unfolded to native conformation, was observed within 300 micros after the pH jump. The collapsed intermediate has a f(H) of 33% and a globular shape that involves >80% of all its atoms. Subsequently, a stepwise helix formation was detected, which was interpreted to be associated with a conformational search for the correct tertiary contacts. The characterized folding dynamics of apoMb indicates the importance of the initial collapse event, which is suggested to facilitate the subsequent conformational search and the helix formation leading to the native structure. | ||||
Address | Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, 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 | 0027-8424 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:14711991 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 3779 | ||
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Author | Ballew, R.M.; Sabelko, J.; Gruebele, M. | ||||
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 | 3798 | ||
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Author | König von Borstel, U.; Kienapfel, K.; McLean, A.; Wilkins, C.; Evans, D.; McGreevy, P. | ||||
Title | Hyperflexing the horse‘s neck: a cost-benefit and meta-analysis | Type | Conference Article | ||
Year | 2015 | Publication | Proceedings of the 3. International Equine Science Meeting | Abbreviated Journal | Proc. 3. Int. Equine. Sci. Mtg |
Volume | Issue | Pages | |||
Keywords | horse, head-and-neck posture, hyperflexion, welfare, gymnastics | ||||
Abstract | In ethical discussions, a cost-benefit analysis requires that welfare costs associated with an activity can be reliably estimated and balanced against the potential benefits of the activity to both humans and animals. The current study applies a meta-analysis to the peer-reviewed evidence for costs and benefits of hyperflexion of the neck in horses; a practice that has attracted enormous public and scientific scrutiny over the past 15 years. A literature review identified 55 studies dealing with horses’ head and neck postures. Fourty-two of these studies examined the impact of various postures on equine welfare, for example, by assessing behavior, physiological stress parameters, health or rider-horse interaction. Thirty-five studies examined the impact of various postures on gymnastics (e.g. kinematics, shifts in weight distribution, muscle activity, airway functioning or overall workload). For the meta-analysis a dataset containing information from each of the individual studies was created. Data included information such as type, degree, duration and circumstances of hyperflexion applied in that particular study as well as information on the horses (e.g., sport discipline, level of training, breed) and on the study design (e.g., size of study and experimental or epidemiological research design). The results of the study regarding the impact of hyperflexion on a) welfare and b) gymnastics were coded as positive (1), insignificant or contradictory (0) or negative (-1). The significant majority of studies (88%) concluded that a hyperflexed head and neck posture negatively impacts welfare. Just one study suggested welfare advantages of training in a hyperflexed head and neck posture. An analysis using a generalized linear mixed model to assess the influence of the above factors collated in the dataset revealed that none of these factors significantly influenced the probability of a study to detect negative welfare implications. Thus hyperflexing the neck appears to impair horses’ welfare regardless of, for example, the duration or the way of achieving hyperflexion. A concurrent assessment of the evidence for gymnastic benefits showed that approximately one quarter of studies conclude that there may be benefits, while another quarter of the studies conclude that hyperflexion has detrimental effects on gymnastics. Thus, on the costs-side there is a clear reduction in equine welfare and some undesirable gymnastic effects, as well as likely a compromised profile of the equestrian sports in public. Benefits, on the other hand, include some desirable gymnastic effects, and potentially increased control of the horse for the rider. On balance, it appears that the costs associated with hyperflexion exceed the potential benefits of the activity to both humans and horses. | ||||
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Corporate Author | König von Borstel, U. | Thesis | |||
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Notes | Approved | no | |||
Call Number | Equine Behaviour @ team @ | Serial | 5872 | ||
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Author | Baragli, P.; Demuru, E.; Palagi, E. | ||||
Title | Mirror on the wall, who is the horsest of our all? Self-recognition in Equus caballus | Type | Conference Article | ||
Year | 2015 | Publication | Proceedings of the 3. International Equine Science Meeting | Abbreviated Journal | Proc. 3. Int. Equine. Sci. Mtg |
Volume | Issue | Pages | |||
Keywords | Domestic horse • Mark test • Socio-cognitive skills • Self-awareness | ||||
Abstract | Mirror Self-Recognition (MSR) is an extremely rare capacity in the animal kingdom that reveals the emergence of complex cognitive capacities (de Waal 2008). So far, MSR has been reported only in humans, chimpanzees (Gallup, 1970), bottlenose dolphins (Reiss and Marino, 2001) and Asian elephants (Plotnik et al, 2006), all species characterized by a highly developed cognition. There is growing evidence that domestic horses posses high cognitive abilities, such as cross-modal individual recognition (Proops et al, 2009), triadic post-conflict reunion to maintain social homeostasis (Cozzi et al, 2010), complex communicative systems (Whatan and McComb, 2014), flexibility in problem-solving (Lovrovich et al, 2015), and long-term memory (Hanggi and Ingersoll, 2009). All these capacities make horses a good candidate to test the ability of MSR in a domestic species. Through a classical MSR experimental paradigm (de Waal 2008) we tested eight horses living in social groups under semi-natural conditions (from the Italian Horse Protection rescue centre). Animals showing MSR typically go through four stages (Plotnik et al, 2006): (i) social response, (ii) physical mirror inspection (e.g., looking behind the mirror), (iii) repetitive mirror-testing behaviour (i.e., the beginning of mirror understanding), and (iv) self-directed behaviour (i.e., recognition of the mirror image as self). The final stage, known as the “mark-test”, is verified when a subject spontaneously uses the mirror to check for a coloured artificial mark on its own body which it cannot perceive otherwise. The horses underwent a three-phase “mark-test”: 1) with sham mark (transparent ultrasound water gel) positioned on both side at jaw level, 2) mark (yellow eye shadow mixed with ultrasound water gel) positioned on left side of jaw (with sham mark on the right), 3) mark (yellow eye shadow mixed with ultrasound water gel) positioned on right side of jaw (with sham mark on the left) The mirror was one 0.5-cm-thick piece of 140x220-cm plexiglass glue on wood. Each test lasted one hour, horses were tested once a day, in consecutive days and at the same time. Our preliminary result on 1 horse shows some changes in self-directed behaviours which can be attributed to presence of the coloured mark. Firstly, the presence of the coloured mark significantly increased the frequency of scratching on both sides of the muzzle (p < 0.0001). The most intriguing result (p < 0.0001) comes from the comparison of the scratching rates directed towards the coloured mark side (N = 41) and the sham mark side (N = 23). Under the control condition (i.e. sham mark on both sides) no statistical difference was found for the scratching rates directed to the muzzle sides (dx N = 8; sx N = 5). Although further analyses are needed to confirm these preliminary results, our finding opens new scenarios about the evolution of Mirror Self-Recognition. The capacity of horses to recognize themselves in a mirror may be the outcome of an evolutionary convergence process driven by the cognitive pressures imposed by a complex social system and maintained despite thousands years of domestication. Keywords: Domestic horse · Mark test · Socio-cognitive skills · Self-awareness References De Waal FBM (2008) The thief in the mirror. PloS Biol 6(8):e201 Gallup GG Jr (1970) Chimpanzees: Self-recognition. Science 167: 86-87. Reiss D, Marino L (2001). Mirror self-recognition in the bottlenose dolphin: A case of cognitive convergence. Proc Natl Acad Sci U S A 98:5937-5942. Plotnik J, de Waal FBM, Reiss D (2006) Self-recognition in an Asian elephant. Proc Natl Acad Sci U S A 103: 17053-17057. Proops L, McComb K, Reby D. (2009) Cross-modal individual recognition in domestic horses (Equus caballus). Proc Nat Acad Sci USA;106:947-951. Cozzi A, Sighieri C, Gazzano A, Nicol CJ, Baragli P. Post-conflict friendly reunion in a permanent group of horses (Equus caballus). Behav Process 2010;85:185-190. Wathan J, McComb K. The eyes and ears are visual indicators of attention in domestic horses. Curr Biol 2014;24(15): R677-R679. Lovrovich P, Sighieri C, Baragli P (2015) Following human-given cues or not? Horses (Equus caballus) get smarter and change strategy in a delayed three choice task. Appl Anim Behav Sci, in press. Hanggi EB, Ingersoll JF. (2009) Long-term memory for categories and concepts in horses (Equus caballus). Anim Cogn; 12:451-462. |
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Corporate Author | Baragli, P. | Thesis | |||
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Notes | Approved | no | |||
Call Number | Equine Behaviour @ team @ | Serial | 5874 | ||
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