Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    Electronic Resource
    Electronic Resource
    Light as a trigger for time-resolved structural experiments on muscle, lipids, p21 and bacteriorhodopsin (1991)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 24 (1991), S. 857-865 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: With the availability of synchrotron-radiation facilities, new approaches to time-resolved structural experiments in biology have been developed. The common feature of the experiments described is the use of powerful light sources to trigger structural transitions by flash photolysis, flash excitation or laser temperature jump. Special emphasis will be given to the selection criteria for a laser temperature jump system and to the performance of the selected erbium glass laser as a tool for rapid temperature jumps. Experiments are presented on the structure and kinetics of muscle contraction, lipid phase transition, Ha-ras p21 Laue crystallography and structural changes during the photocycle of bacteriorhodopsin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889890013176
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    31P-Resonanzen im Kernspinresonanzspektrum (1984)
    Springer
    Research in experimental medicine 184 (1984), S. 131-132 
    Details
    ISSN: 1433-8580
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01852360
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    31P-NMR spectra of AP4 (1985)
    Springer
    Research in experimental medicine 185 (1985), S. 145-150 
    Details
    ISSN: 1433-8580
    Keywords: 31P-NMR spectra ; AP4 ; Resonances
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 31P-NMR spectra were obtained from adenosine-5′-tetraphosphate under a variety of conditions and the four discernible resonances assigned. The pK-value of the metal-free compound was determined to be 6.4, the pK-value of the Mg2+ complex to be 5.3. The dissociation constant for the AP4⋅Mg2+ complex was estimated to be 10−4 M from the downfield shift of the resonances assigned to theγ- andδ-phosphorus nuclei. The binding of a second metal ion can also be followed by NMR; the dissociation constant for this ternary complex is several orders of magnitude larger than that for the binary complex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01854900
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    The molecular basis of contractility Part I (1974)
    Springer
    Basic research in cardiology 69 (1974), S. 88-104 
    Details
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Muscular contraction stems from a sliding movement of thick and thin filaments relative to each other. These filaments run parallel to the direction of the muscle fibre. The thin filaments, which issue from the Z-membrane into the sarcomere, consist of 60% actin, and 40% regulator proteins (tropomyosin and troponin). The thick filament consists almost entirely of myosin. The two types of filaments form on overlapping region, the length of which depends on the degree of shortening of the muscle. The mechanical work which is produced by the muscle during shortening is produced by the so-called myosin cross-bridges, which appear to attach to actin, change their angle, and then detach in a cyclical “rowing-boat” manner. During such a cycle, ATP is split to ADP and inorganic phosphate, and therefore the production of mechanical work is based on the interaction of actin and myosin at the expense of chemical energy, which is supplied in the form of ATP. In the last 20 years, the structure of the involved proteins and their aggregation and ordering in the filaments has been widely investigated. Similarly, the rough nature of the electromechanical coupling process has been explained. i. e. the sequence of events which is necessary to activate a resting muscle into contraction via a neural impulse. At the present time, much interest is concentrated on the kinetic analysis of ATP hydrolysis and the modification of certain reaction steps by actin. From experiments of this sort, a more detailed and propound understanding of the nature of the mechanochemical energy coupling mechanism can be expected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01910790
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    The molecular basis of contractility Part II (1974)
    Springer
    Basic research in cardiology 69 (1974), S. 204-213 
    Details
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Zusammenfassung Die Muskelkontraktion beruht auf dem aneinander-vorbei-Gleiten von dicken und dünnen Filamenten, die innerhalb der Muskelzelle parallel zur Faserrichtung verlaufen. Die dünnen Filamente, die von der Z-Linie ausgehend in die Sarkomere reichen, bestehen zu 60% aus dem Protein Aktin und zu 40% aus den Regulatorproteinen Tropomyosin und Tropomin. Das dicke Filament ist fast ausschließlich aus dem Protein Myosin aufgebaut. Beide Filamenttypen bilden eine Überlappungszone, deren Breite vom Ausmaß der Verkürzung der Muskelzelle abhängig ist. Die mechanische Kraft, die notwendig ist, um die beiden Filamente aneinander vorbeizutreiben, wird von der s. g. Myosinquerbrücke erzeugt, die in einer Art Ruderbewegung sich zyklisch am Aktinfilament anheftet, umknickt und wieder losläßt. Während dieses Vorgangs wird ATP zu ADP und anorganischem Phosphat vom Myosin hydrolysiert. Der molekulare Vorgang der Kraftgeneration innerhalb der Muskelzelle beruht somit auf der Interaktion der beiden Proteine Aktin und Myosin bei Verbrauch von chemischer Energie, die in Form von ATP vorliegt. In den letzten 20 Jahren ist die Struktur der beteiligten Proteine, die Art ihrer Aggregation in den Filamenten und die relative Anordnung der Filamente zueinander eingehend erforscht worden. Ebenfalls in groben Zügen ist auf molekularer Ebene der elektromechanische Koppelungsvorgang geklärt, d. h. die Sequenz von Vorgängen, die nötig sind, einen Muskel in Ruhe durch einen neuralen Impuls in einen sich aktiv verkürzenden zu verwandeln. Im Augenblick konzentriert sich das Interesse auf die kinetische Analyse der Hydrolyse des ATPs durch Myosin und den modifizierenden Einfluß des Aktins auf bestimmte Reaktionsschritte der ATP-Bindung und Spaltung am Myosin. Von derartigen Untersuchungen ist ein tieferer Einblick in den Vorgang der chemotechnischen Energieumwandlung auf molekularer Ebene zu erwarten.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01906200
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    The European Molecular Biology Organization Workshop on the Structure and Mechanism of Muscle, Alpbach, March 1980 (1980)
    Springer
    Journal of muscle research and cell motility 1 (1980), S. 251-253 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00711930
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Time-resolved X-ray diffraction studies on stretch-activated insect flight muscle (1991)
    Springer
    Journal of muscle research and cell motility 12 (1991), S. 208-215 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The specific feature of stretch activation of the indirect flight muscle of the tropical waterbugLethocerus was used to correlate mechanical and structural aspects of muscle contraction. The time courses of the changes in intensities of the strongest equatorial reflections, the (10) and (20) and of the first meridional reflection at 14.5 nm−1 were monitored using synchrotron radiation as a high intensity X-ray source. The ratio of the intensities of the equatorial reflections, (I20/I10), which reflects the mass distribution within the filament lattice array, increases by about 10% relative to the Ca2+-activated level when a rapid stretch is imposed, compared with a 200% change seen when fibres change from the relaxed to the rigor state, while the spacing of the lattice planes decreases by about 1%. The intensity of the first meridional reflection at 14.5 nm−1 decreases by about 35% during stretch activation with a slightly faster time course than the delayed tension increase. The results suggest that the average structure of cycling crossbridges is different from that present in the rigor state.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01774040
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    The European Molecular Biology Organization/Muscular Dystrophy Association Workshop on the Structure of Actin and Myosin and the Mechanism of their Interaction, Alpbach, March 1983 (1983)
    Springer
    Journal of muscle research and cell motility 4 (1983), S. 391-394 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00711945
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Stereochemical aspects of the interaction of myosin and actomyosin with nucleotides (1980)
    Springer
    Journal of muscle research and cell motility 1 (1980), S. 101-115 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The five possible analogues of ATP and the three possible analogues of ADP which contain single non-bridging sulphur atoms instead of oxygen in the polyphosphate structure have been used as probes of the interaction of nucleotides with myosin and actomyosin. Evidence is presented for the requirement of an α, β, γ-tridentate complex of magnesium and ATP as the substrate for myosin. Of the four possible tridentate MgATP diastereomers, the Δ exo isomer (nomenclature of Cornelius & Cleland, 1978) appears to be the actual substrate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00711928
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Kinetics of acto-S1 interaction as a guide to a model for the crossbridge cycle (1984)
    Springer
    Journal of muscle research and cell motility 5 (1984), S. 351-361 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Recent experiments on the kinetics of the interaction between myosin subfragment 1 (S1) and F-actin in solution are summarized. It is concluded that, at every step of the ATPase cycle, the association between the two proteins takes place in two stages. The equilibrium constant of the second step and thus the affinity of S1 for actin changes from step to step during the enzymatic reaction. It is proposed that the transient kinetic evidence can be interpreted in terms of two different classes of contraction models. The first one, which is widely used at present, identifies particular steps in the enzymatic reaction as directly responsible for the conformational change which represents the power stroke of muscle contraction (direct coupling model). In the second class of model, to which we wish to draw attention, changes in affinity modulated by the enzymatic reaction result in changes in the relative amounts of time spent by parts of the myosin molecule in two different environments. These environments determine whether the molecule exists in the ‘long’ or ‘short’ state, and it is the transition between these two which constitutes the power stroke (indirect coupling model).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00818255
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...