1
|
Szántó JK, Dietschreit JCB, Shein M, Schütz AK, Ochsenfeld C. Systematic QM/MM Study for Predicting 31P NMR Chemical Shifts of Adenosine Nucleotides in Solution and Stages of ATP Hydrolysis in a Protein Environment. J Chem Theory Comput 2024; 20:2433-2444. [PMID: 38497488 DOI: 10.1021/acs.jctc.3c01280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
NMR (nuclear magnetic resonance) spectroscopy allows for important atomistic insights into the structure and dynamics of biological macromolecules; however, reliable assignments of experimental spectra are often difficult. Herein, quantum mechanical/molecular mechanical (QM/MM) calculations can provide crucial support. A major problem for the simulations is that experimental NMR signals are time-averaged over much longer time scales, and since computed chemical shifts are highly sensitive to local changes in the electronic and structural environment, sufficiently large averages over representative structural ensembles are essential. This entails high computational demands for reliable simulations. For NMR measurements in biological systems, a nucleus of major interest is 31P since it is both highly present (e.g., in nucleic acids) and easily observable. The focus of our present study is to develop a robust and computationally cost-efficient framework for simulating 31P NMR chemical shifts of nucleotides. We apply this scheme to study the different stages of the ATP hydrolysis reaction catalyzed by p97. Our methodology is based on MM molecular dynamics (MM-MD) sampling, followed by QM/MM structure optimizations and NMR calculations. Overall, our study is one of the most comprehensive QM-based 31P studies in a protein environment and the first to provide computed NMR chemical shifts for multiple nucleotide states in a protein environment. This study sheds light on a process that is challenging to probe experimentally and aims to bridge the gap between measured and calculated NMR spectroscopic properties.
Collapse
Affiliation(s)
- Judit Katalin Szántó
- Chair of Theoretical Chemistry, Department of Chemistry, University of Munich (LMU), Butenandtstr. 7, D-81377 München, Germany
| | - Johannes C B Dietschreit
- Chair of Theoretical Chemistry, Department of Chemistry, University of Munich (LMU), Butenandtstr. 7, D-81377 München, Germany
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mikhail Shein
- Department of Chemistry, University of Munich (LMU), Butenandtstr. 5-13, D-81377 München, Germany
| | - Anne K Schütz
- Department of Chemistry, University of Munich (LMU), Butenandtstr. 5-13, D-81377 München, Germany
| | - Christian Ochsenfeld
- Chair of Theoretical Chemistry, Department of Chemistry, University of Munich (LMU), Butenandtstr. 7, D-81377 München, Germany
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, D-70569 Stuttgart, Germany
| |
Collapse
|
2
|
Elghobashi-Meinhardt N. ATP hydrolysis captured in atomic detail. Nat Chem 2024; 16:306-307. [PMID: 38429342 DOI: 10.1038/s41557-024-01466-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
|
3
|
Shein M, Hitzenberger M, Cheng TC, Rout SR, Leitl KD, Sato Y, Zacharias M, Sakata E, Schütz AK. Characterizing ATP processing by the AAA+ protein p97 at the atomic level. Nat Chem 2024; 16:363-372. [PMID: 38326645 PMCID: PMC10914628 DOI: 10.1038/s41557-024-01440-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 01/04/2024] [Indexed: 02/09/2024]
Abstract
The human enzyme p97 regulates various cellular pathways by unfolding hundreds of protein substrates in an ATP-dependent manner, making it an essential component of protein homeostasis and an impactful pharmacological target. The hexameric complex undergoes substantial conformational changes throughout its catalytic cycle. Here we elucidate the molecular motions that occur at the active site in the temporal window immediately before and after ATP hydrolysis by merging cryo-EM, NMR spectroscopy and molecular dynamics simulations. p97 populates a metastable reaction intermediate, the ADP·Pi state, which is poised between hydrolysis and product release. Detailed snapshots reveal that the active site is finely tuned to trap and eventually discharge the cleaved phosphate. Signalling pathways originating at the active site coordinate the action of the hexamer subunits and couple hydrolysis with allosteric conformational changes. Our multidisciplinary approach enables a glimpse into the sophisticated spatial and temporal orchestration of ATP handling by a prototype AAA+ protein.
Collapse
Affiliation(s)
- Mikhail Shein
- Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
- Bavarian NMR Center, Technical University of Munich, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Manuel Hitzenberger
- Physics Department and Center of Protein Assemblies, Technical University of Munich, Garching, Germany.
| | - Tat Cheung Cheng
- Institute for Neuropathology, University Medical Center Göttingen, Göttingen, Germany
- Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells (MBExC), University of Göttingen, Göttingen, Germany
| | - Smruti R Rout
- Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells (MBExC), University of Göttingen, Göttingen, Germany
- Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
| | - Kira D Leitl
- Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
- Bavarian NMR Center, Technical University of Munich, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Yusuke Sato
- Center for Research on Green Sustainable Chemistry, Graduate School of Engineering, Tottori University, Tottori, Japan
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Martin Zacharias
- Physics Department and Center of Protein Assemblies, Technical University of Munich, Garching, Germany.
| | - Eri Sakata
- Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells (MBExC), University of Göttingen, Göttingen, Germany.
- Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany.
| | - Anne K Schütz
- Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, München, Germany.
- Bavarian NMR Center, Technical University of Munich, Garching, Germany.
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.
| |
Collapse
|
4
|
Johnson KA. History of advances in enzyme kinetic methods: From minutes to milliseconds. Enzymes 2023; 54:107-134. [PMID: 37945168 DOI: 10.1016/bs.enz.2023.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
The last review on transient-state kinetic methods in The Enzymes was published three decades ago (Johnson, K.A., 1992. The Enzymes, XX, 1-61). In that review the foundations were laid out for the logic behind the design and interpretation of experiments. In the intervening years the instrumentation has improved mainly in providing better sample economy and shorter dead times. More significantly, in 1992 we were just introducing methods for fitting data based on numerical integration of rate equations, but the software was slow and difficult to use. Today, advances in numerical integration methods for data fitting have led to fast and dynamic software, making it easy to fit data without simplifying approximations. This approach overcomes multiple disadvantages of traditional data fitting based on equations derived by analytical integration of rate equations, requiring simplifying approximations. Mechanism-based fitting using computer simulation resolves mechanisms by accounting for the concentration dependence of the rates and amplitudes of the reaction to find a set of intrinsic rate constants that reproduce the experimental data, including details about how the experiment was performed in modeling the data. Rather than discuss how to design and interpret rapid-quench and stopped-flow experiments individually, we now focus on how to fit them simultaneously so that the quench-flow data anchor the interpretation of fluorescence signals. Computer simulation streamlines the fitting of multiple experiments globally to yield a single unifying model to account for all available data.
Collapse
Affiliation(s)
- Kenneth A Johnson
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States.
| |
Collapse
|
5
|
Rydzek S, Shein M, Bielytskyi P, Schütz AK. Observation of a Transient Reaction Intermediate Illuminates the Mechanochemical Cycle of the AAA-ATPase p97. J Am Chem Soc 2020; 142:14472-14480. [DOI: 10.1021/jacs.0c03180] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Simon Rydzek
- Bavarian NMR Center, Department of Chemistry, Technical University of Munich, 85748 Garching, Germany
| | - Mikhail Shein
- Bavarian NMR Center, Department of Chemistry, Technical University of Munich, 85748 Garching, Germany
| | - Pavlo Bielytskyi
- Bavarian NMR Center, Department of Chemistry, Technical University of Munich, 85748 Garching, Germany
| | - Anne K. Schütz
- Bavarian NMR Center, Department of Chemistry, Technical University of Munich, 85748 Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| |
Collapse
|
6
|
Heeley DH, White HD, Taylor EW. Investigation into the mechanism of thin filament regulation by transient kinetics and equilibrium binding: Is there a conflict? J Gen Physiol 2019; 151:628-634. [PMID: 30824574 PMCID: PMC6504287 DOI: 10.1085/jgp.201812198] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/23/2018] [Accepted: 02/07/2019] [Indexed: 11/22/2022] Open
Abstract
The authors examine the apparent discrepancies from studies aimed at understanding the mechanism of thin filament regulation. Striated muscle contraction occurs when myosin undergoes a lever-type structural change. This process (the power stroke) requires ATP and is governed by the thin filament, a complex of actin, tropomyosin, and troponin. The authors have used a fast-mixing instrument to investigate the mechanism of regulation. Such (pre–steady-state kinetic) experiments allow biochemical intermediates in a working actomyosin cycle to be monitored. The regulatory focal point is demonstrated to be the step that involves the departure of inorganic phosphate (i.e., AM-ADP-Pi → AM-ADP). This part of the cycle, which lies on the main kinetic pathway and coincides with the drive stroke, is maximally accelerated ∼100-fold by the combined association of ligands (Ca[II] and rigor myosin heads) with the thin filament. However, the observed ligand dependencies of the rates of Pi dissociation that are reported herein are at variance with predictions of models derived from experiments where ATP hydrolysis is not taking place (and myosin exists in a nonphysiological form). It is concluded that the principal influence of the thin filament is in setting the rate of Pi dissociation and that physiological levels of regulation are dependent upon the liganded state of the thin filament as well as the conformation of myosin.
Collapse
Affiliation(s)
- David H Heeley
- Department of Biochemistry, Memorial University, St. John's, Canada
| | - Howard D White
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA
| | - Edwin W Taylor
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| |
Collapse
|
7
|
Abstract
Two misleading conclusions drawn from the classical treatment of thermodynamics are, first, that single molecules cannot be treated thermodynamically and, second, that all real processes must be irreversible. The first conclusion has meant that the disruptive effect of thermal motions has been ignored, the second has meant that dynamic forces which cannot exist without stored energy, have been left out of account. The effect of these beliefs is demonstrated by analysis in detail of a simple electrostatic model of muscle. It is shown that the necessity of protecting each step against decay of the stored energy, and the requirement that each should be specific, has the effect of stopping the model actually working. Moreover, the character of static forces, which are strongest after their stored energy has been used up, precludes their use in cyclic processes because as much stored energy is required to undo them later in the cycle. Covalent intermediates are also examined from a quantum mechanical viewpoint and it is shown how these store energy which can be transferred by resonant transitions in the ground state when groups like phosphate are transferred chemically between molecules. But this analysis shows that, necessarily, the energy remains stored and therefore not available for muscular contraction. Then it follows naturally both that bond vibrations are produced in exothermic chemical reactions and that, because the force disappears when the energy has been used up, resonant exchange of stored energy in the excited state should solve the difficulties of previous approaches to these problems.
Collapse
|
8
|
Barman TE, Travers F. The rapid-flow-quench method in the study of fast reactions in biochemistry: extension to subzero conditions. METHODS OF BIOCHEMICAL ANALYSIS 2006; 31:1-59. [PMID: 3160914 DOI: 10.1002/9780470110522.ch1] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
9
|
Phan BC, Cheung P, Stafford WF, Reisler E. Complexes of myosin subfragment-1 with adenosine diphosphate and phosphate analogs: probes of active site and protein conformation. Biophys Chem 1996; 59:341-9. [PMID: 8672721 DOI: 10.1016/0301-4622(95)00127-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Previous work has revealed phosphate-dependent differences in the complexes formed from myosin subfragment-1 with adenosine diphosphate (S1.ADP) and aluminum fluoride (AlF4-) or beryllium fluoride (BeFx) [Phan and Reisler, Biophys. J., 66 (1994) A78], with the former resembling more the S1**.ADP.Pi state while the latter resembles more the S1.ATP state. In this work, the conformations of the S1.epsilon ADP.AlF4- and S1.epsilon ADP.BeFx, complexes were examined by nucleotide chase and collisional quenching experiments. epsilon ADP release from S1.epsilon ADP.AlF4- was slower than that from S1.epsilon ADP.BeFx. However, acrylamide titrations of S1.epsilon ADP.AlF4- and S1.epsilon ADP.BeFx showed little difference in nucleotide protection from quenching between the two complexes. This contrasts with the earlier observation on phosphate analog-dependent changes in the reactivity of the SH1 group on S1. To confirm phosphate-related perturbation of the SH1-SH2 sequence, emission spectra of fluorescein (IAF)-labeled SH1 and IANBD-labeled SH2 were recorded for S1 complexes with nucleotides and phosphate analogs. Considerable differences were found between the BeFx and AlF4- complexes with S1.MgADP for both SH1- and SH2-labeled proteins. These results are consistent with a recent crystallographic study of S1 complexes with ADP and phosphate analogs [Fisher et al., Biophys. J., 68 (1995) 19S] and the idea that the opening of the nucleotide cleft on S1 does not change much during ATP hydrolysis [Franks-Skiba et al., Biochemistry, 33 (1994) 12720], while significant changes in the SH1-SH2 region accompany phosphate cleavage.
Collapse
Affiliation(s)
- B C Phan
- Department of Chemistry and Biochemistry, University of California, Los Angeles 90095, USA
| | | | | | | |
Collapse
|
10
|
Abstract
Striated and smooth muscles have different mechanisms of regulation of contraction which can be the basis for selective pharmacological alteration of the contractility of these muscle types. The progression in our understanding of the tropomyosin-troponin regulatory system of striated muscle from the early 1970s through the early 1990s is described along with key concepts required for understanding this complex system. This review also examines the recent history of the putative contractile regulatory proteins of smooth muscle, caldesmon and calponin. A contrast is made between the actin linked regulatory systems of striated and smooth muscle.
Collapse
Affiliation(s)
- J M Chalovich
- Department of Biochemistry, East Carolina University, School of Medicine, Greenville, NC 27858-4354
| |
Collapse
|
11
|
Hebisch S, Soboll S, Schwenen M, Sies H. Compartmentation of high-energy phosphates in resting and working rat skeletal muscle. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 764:117-24. [PMID: 6696884 DOI: 10.1016/0005-2728(84)90020-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The subcellular distribution of high-energy phosphates in various types of skeletal muscle of the rat was analysed by subfractionation of tissues in non-aqueous solvents. Different glycolytic and oxidative capacities were calculated from the ratio of phosphoglycerate kinase and citrate synthase activities, ranging from 25 in m. soleus to 130 in m. tensor fasciae latae. In the resting state, the subcellular contents of ATP, creatine phosphate and creatine were similar in m. soleus, m. vastus intermedius, m. gastrocnemius and m. tensor fasciae latae but, significantly, a higher extramitochondrial ADP-content was found in m. soleus. A similar observation was made in isometrically and isotonically working m. gastrocnemius. The extramitochondrial, bound ADP accounted fully for actin-binding sites in resting fast-twitch muscles, but an excess of bound ADP was found in m. soleus and working m. gastrocnemius. The amount of non-actin-bound ADP reached maximal values of approx. 1.2 nmol/mg total protein. It could not be enhanced further by prolonged isotonic stimulation or by increased isometric force development. It is suggested that non-actin-bound ADP is accounted for by actomyosin-ADP complexes generated during the contraction cycle. Binding of extramitochondrial ADP to actomyosin complexes in working muscles thus acts as a buffer for cytosolic ADP in addition to the creatine system, maintaining a high cytosolic phosphorylation potential also at increasing rates of ATP hydrolysis during muscle contraction.
Collapse
|
12
|
Watterson JG, Foletta D, Kunz PA, Schaub MC. Interaction of ADP and magnesium with the active site of myosin subfragment-1 observed by reactivity changes of the critical thiols and by direct binding methods at low and high ionic strength. EUROPEAN JOURNAL OF BIOCHEMISTRY 1983; 131:89-96. [PMID: 6832146 DOI: 10.1111/j.1432-1033.1983.tb07234.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Comprehensive binding studies using direct and indirect methods yield stoichiometry and affinities for the binding of Mg X ADP and uncomplexed ADP to the active site of myosin subfragment-1. Additionally, the binding parameters for Mg2+ in the ternary complex protein X Mg X ADP are presented for the first time. The indirect method makes use of reactivity changes of the critical thiol-1 and thiol-2 groups, which occur upon the binding of the ligand at the active site. The affinity constants derived by this method are corroborated by two independent direct methods, equilibrium dialysis and centrifugation transport. For Mg2+, ADP and Mg X ADP just one mole of ligand binds/mole subfragment-1. The affinity of Mg X ADP at low ionic strength is 2.1 X 10(6) M-1 and only five-times lower in the absence of Mg2+. In the ternary complex Mg2+ has a low affinity of 4.1 X 10(4) M-1. At high ionic strength the uncomplexed ADP binds with a 43-times-lower affinity than Mg X ADP, whose affinity is 6.9 X 10(5) M-1. In this case Mg2+ interacts in the ternary complex with the higher affinity of 3.2 X 10(5) M-1, implying that at high salt concentration it plays a more prominent role in anchoring ADP at the active site.
Collapse
|
13
|
Fogel AG. Cooperativity of enzymatic reactions and molecular aspects of energy transduction. Mol Cell Biochem 1982; 47:59-64. [PMID: 7132966 DOI: 10.1007/bf00241567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
This theoretical article concerns the basic principles of enzymatic conversion at the molecular level. The high rate of enzymatic reactions can be explained by a concept of collective substrate conversion of a cooperative nature. The proposed mechanism of charge separation in electron transport includes two aspects: electron tunnelling and coupled proton transfer. Energy transduction in muscle contraction and oxidative phosphorylation is outlined.
Collapse
|
14
|
Sleep JA, Trybus KM, Johnson KA, Taylor EW. Kinetic studies of normal and modified heavy meromyosin and subfragment-1. J Muscle Res Cell Motil 1981. [DOI: 10.1007/bf00711966] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
15
|
|
16
|
Strzelecka-Gołaszewska H, Klimaszewska U, Dydyńska M. Polyphasic character of ATP hydrolysis in actomyosin system. EUROPEAN JOURNAL OF BIOCHEMISTRY 1979; 101:523-30. [PMID: 160315 DOI: 10.1111/j.1432-1033.1979.tb19747.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
17
|
|
18
|
Taylor EW. Mechanism of actomyosin ATPase and the problem of muscle contraction. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1979; 6:103-64. [PMID: 156624 DOI: 10.3109/10409237909102562] [Citation(s) in RCA: 357] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
19
|
Chantler PD, Szent-Györgyi AG. Spectroscopic studies on invertebrate myosins and light chains. Biochemistry 1978; 17:5440-8. [PMID: 215199 DOI: 10.1021/bi00618a018] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
20
|
Schaub MC, Watterson JG, Walser JT, Waser PG. Hydrolytically induced allosteric change in the heavy chain of intact myosin involving nonessential thiol groups. Biochemistry 1978; 17:246-53. [PMID: 339944 DOI: 10.1021/bi00595a009] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The two globular head portions, each bearing an active site, contain an uncleaved heavy chain when isolated by chymotrypsin from intact myosin. By specific labeling with radioactive N-ethylmaleimide the essential thiol 1 and thiol 2 groups were found to reside in this heavy chain. In intact myosin nonessential thiol 3 groups become the most reactive during ATP hydrolysis above 15 degrees C. These thiol 3 groups are located in a portion of the myosin heavy chain which appears as a fragment with an apparent molecular weight of 11 000 during proteolysis. The facts that this fragment is produced in an almost 1: 1 molar ratio with the head heavy chain and that it bears unblocked N-terminal amino groups whereas the heavy chain does not and is not contained in the rod portion of the myosin molecule indicate that it may orginate from the heavy chains in the neck region where the heads are joined to the rod. Since this fragment is removed by ion-exchange chromatography, it is not part of the functioning head and hence not involved in the active site. As its nonessential thiol 3 groups are rendered the most reactive of all thiol groups in the enzyme-product complex M**ADP.Pi, the hydrolytic step induces an allosteric conformational change in the neck region of intact myosin.
Collapse
|
21
|
Hundley RF, Wynn J. Role of ADP in the control of actomyosin superprecipitation and ATPase activity. Arch Biochem Biophys 1977; 179:432-43. [PMID: 139848 DOI: 10.1016/0003-9861(77)90131-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
22
|
Tonomura Y, Inoue A. Yuji Tonomura and Akio Inoue — there must be two pathways. Trends Biochem Sci 1977. [DOI: 10.1016/0968-0004(77)90245-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
23
|
Neraal R, Hamm R. [On the enzymatic breakdown of tripolyphosphate and diphosphate in minced meat II. occurence of tripolyphosphatase in muscular tissue (author's transl)]. ZEITSCHRIFT FUR LEBENSMITTEL-UNTERSUCHUNG UND -FORSCHUNG 1977; 163:18-20. [PMID: 189526 DOI: 10.1007/bf01123550] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
After a review on the present knowledge of the occurence of tripolyphosphatase in muscular tissue own data of the tripolyphosphatase activity in the bovine longissimus muscle of seven animals are reported. Remarkable differences between animals were observed which seem to depend on the pH of tissue.
Collapse
|
24
|
Lehman W. Phylogenetic diversity of the proteins regulating muscular contraction. INTERNATIONAL REVIEW OF CYTOLOGY 1976; 44:55-92. [PMID: 131113 DOI: 10.1016/s0074-7696(08)61647-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
25
|
Watterson JG, Schaub MC, Locher R, Di Pierri S, Kutzer M. Temperature-induced transitions in the conformation of intermediates in the hydrolytic cycle of myosin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1975; 56:79-90. [PMID: 240711 DOI: 10.1111/j.1432-1033.1975.tb02209.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The conformations of the transitory intermediates of the myosin ATPase occurring during the hydrolytic cycle, enzyme without ligand, enzyme-substrate complex and two different forms of enzyme-product complex, have been characterized in terms of numbers and classes of reactive thiol groups based on incorporation of radioactively labeled alkylation reagent. The techniques employed allowed this to be done under steady-state conditions in the presence of high ligand concentrations on intact myosin from rabbit fast skeletal muscles at low ionic strength where the protein is in the gel state as it is in muscle. The binding of a divalent cation (Mg2+ or Ca2+) nucleotide complex exposes thiol-1 as well as thiol-2 groups. The long-lived ATPase intermediate occurring at temperatures above 10 degrees C adopts the same conformation with Mg2+ and Ca2+ ions. This intermediate does not protect the thiol-1 and thiol-2 groups but exposes a number of thiol-3 groups which seem to be located distant from the active site. The conformation of the intermediate prevailing in the presence of ATP changes with lowering temperature below 10 degrees C and is identical with that found in the presence of ADP at 0 degree C indicating a change in the rate-limiting step of the hydrolytic cycle. In the absence of divalent cations no such temperature-dependent change in conformation was observed. Evaluation of the activation entropies shows that the structure of the long-lived intermediate occurring above 10 degrees C in the presence of Mg2+ ions goes through a transformation from low to high order at around 20 degrees C. In the case of the monovalent-cation-stimulated ATPase a constant activation energy of around 70 kJ/mol, typical of many enzyme reactions, was found over the entire temperature range from 0--35 degrees C.
Collapse
|
26
|
Koretz JF, Taylor EW. Transient state kinetic studies of proton liberation by myosin and subfragment 1. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)41072-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
27
|
Fabiato A, Fabiato F. Contractions induced by a calcium-triggered release of calcium from the sarcoplasmic reticulum of single skinned cardiac cells. J Physiol 1975; 249:469-95. [PMID: 809571 PMCID: PMC1309588 DOI: 10.1113/jphysiol.1975.sp011026] [Citation(s) in RCA: 447] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
1. Fragments of single cardiac cells were obtained by homogenization of ventricular tissue from adult rats. Remaining pieces of sacrolemma were removed by micro-dissection. Tension was recorded from the ends of the skinned (sarcolemma-free) cells with a photodiode force transducer. 2. In the presence of a strong buffering of the free [Ca2+] with 4-0 mM total EGTA, a tonic tension was obtained that increased according to t sigmoid curve when the free ([Ca2+] was increased from 10(-6-75)M to 10(-5-0)M. This curve was not modified by the destruction of the sarcoplasmic reticulum (SR) by the detergent Brij 58. Therefore, the tonic tension corresponded to the direct effect of the free [Ca2+] present in the buffer on the myofilaments. 3. In the presence of a slight buffering of the free [Ca2+] with 0-050 mM total EGTA, cyclic contractions were observed that were attributed to cyclic releases and re-sequestrations of Ca2+ by the SR. The absence of effect of azide and ruthenium red on the cyclic contractions obtained at a free [Ca2+] lower than 10(-6-50)M demonstrated that the mitochondria played no role in the triggering of these contractions. 4. Cyclic contractions were induced by a slight variation of free [Ca2+] in the buffer from 10(-7-65)M to 10(-7-40)M. Their amplitude at 10(-7-40)M free Ca2+ was equal to the tonic tension developed by a free [Ca2+] 20 times higher applied to the myofilaments when the SR was destroyed by detergent or functionally inhibited by high total [EGTA]. It was concluded that these cyclic contractions corresponded to a Ca2+-triggered release of Ca2+ from the SR. 5. The cyclic contractions were induced by the filling of the SR with Ca2+ to a critical level at which it released a fraction of the Ca2+ it contained. Each contraction was followed by a re-sequestration of Ca2+, the kinetics of which conditioned the duration of the cycles. 6. The amplitude of the cyclic contractions increased when the free [Ca2+] that triggered them was increased. This gradation was deemed incompatible with a simple regenerative process, which should produce an all-or-nothing response. Additional process, such as a modulation of the Ca2+ release by free [Mg2+] and [ADP] may help to explain the gradation of the contractions. 7. It was concluded that a Ca2+-triggered release of Ca2+ from the SR of rat ventricular cells may amplify the Ca2+ flux crossing the sarcolemma during the plateau of the action potential, thereby permitting the activation of the myofilaments.
Collapse
|
28
|
Goody RS, Holmes KC, Mannherz HG, Leigh JB, Rosenbaum G. Cross-bridge conformation as revealed by x-ray diffraction studies on insect flight muscles with ATP analogues. Biophys J 1975; 15:687-705. [PMID: 1139036 PMCID: PMC1334729 DOI: 10.1016/s0006-3495(75)85848-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The effects of three ATP analogues, alpha,beta-methylene-ATP [ATP(alpha,beta-CH1)], adenosine 5'-0-(3-thiotrophosphate) [ATP(gamma-S)], and beta,gamma-amino-ATP [ATP(beta,gamma-NH)] at various concentrations and temperatures on the X-ray fiber diagrams of glycerinated flight muscles from a water bug (Lethocerus maximus) have been investigated. It is shown that the "relaxed" state can be obtained with all three analogues at high concentrations, the result being particularly clear with ATP(gamma-S). It is inferred that the binding of an ATP-like molecule suffices to produce the relaxed state. At low concentrations ATP(beta,gamma-NH) produces state intermediate between rigor and relaxed which is not simply a mixture of the two. The possible nature of the intermediate is discussed.
Collapse
|
29
|
Hotta K. Intermediate complex of ATP hydrolysis and synthesis by muscle proteins. JOURNAL OF SUPRAMOLECULAR STRUCTURE 1975; 3:333-7. [PMID: 172738 DOI: 10.1002/jss.400030404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Myosin catalyzed exchange between 32Pi and ATP in reaction medium during its enzymatic hydrolysis of ATP only by a very small amount. Addition of actin increased to a great extent the rate of incorporation of 32Pi in the presence of Mg. Glycerinated smooth muscle fibers also exhibited the ability to exchange 32Pi and ATP upon the application of external force (repeated stretching and releasing). A schematic mechanism of the action of actin and external force on acceleration of 32Pi incorporation is proposed and the importance of the M-ADP complex for force generation is suggested.
Collapse
|
30
|
Tonomura Y, Inoue A. The substructure of myosin and the reaction mechanism of its adenosine triphosphatase. Mol Cell Biochem 1974; 5:127-43. [PMID: 4280507 DOI: 10.1007/bf01731376] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
31
|
|
32
|
|
33
|
Blumenfeld LA, Ignatéva LG. Conformational changes in myosin under ATP hydrolysis. EUROPEAN JOURNAL OF BIOCHEMISTRY 1974; 47:75-9. [PMID: 4373241 DOI: 10.1111/j.1432-1033.1974.tb03669.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
34
|
|
35
|
Murphy AJ. Circular dichroism of the adenine and 6-mercaptopurine nucleotide complexes of heavy meromyosin. Arch Biochem Biophys 1974; 163:290-6. [PMID: 4604220 DOI: 10.1016/0003-9861(74)90479-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
36
|
Hozumi T, Tawada K. Kinetics of steady state ATPase activity and rigor complex formation of acto-heavy meromyosin. BIOCHIMICA ET BIOPHYSICA ACTA 1974; 347:469-82. [PMID: 4276404 DOI: 10.1016/0005-2728(74)90084-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
37
|
|
38
|
Schaub MC, Watterson JG. Conformational differences in myosin. Evidence for change in rate limiting step of the magnesium stimulated ITPase of myosin. FEBS Lett 1974; 39:317-21. [PMID: 4368532 DOI: 10.1016/0014-5793(74)80139-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
39
|
|
40
|
|
41
|
|
42
|
Einflu� von Diphosphat (Pyrophosphat) auf den Abbau von Adenosintriphosphat und Glykogen in zerkleinertem Rindermuskelpost mortem. ACTA ACUST UNITED AC 1973. [DOI: 10.1007/bf01140358] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
43
|
|
44
|
|
45
|
Seidel JC, Gergely J. Electron spin resonance of myosin spin labeled at the S1 thiol groups during hydrolysis of adenosine triphosphate. Arch Biochem Biophys 1973; 158:853-63. [PMID: 4361111 DOI: 10.1016/0003-9861(73)90581-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
46
|
|
47
|
|
48
|
Yamada T, Shimizu H, Suga H. A kinetic study of the energy storing enzyme-product complex in the hydrolysis of ATP by heavy meromyosin. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 305:642-53. [PMID: 4270154 DOI: 10.1016/0005-2728(73)90083-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
49
|
Marston S. The nucleotide complexes of myosin in glycerol-extracted muscle fibres. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 305:397-412. [PMID: 4270181 DOI: 10.1016/0005-2728(73)90186-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
50
|
Mannherz HG, Leigh JB, Holmes KC, Rosenbaum G. Identification of the transitory complex myosin-ATP by the use of , -methylene-ATP. NATURE: NEW BIOLOGY 1973; 241:226-9. [PMID: 4266989 DOI: 10.1038/newbio241226a0] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|