51
|
Andrałojć W, Luchinat C, Parigi G, Ravera E. Exploring regions of conformational space occupied by two-domain proteins. J Phys Chem B 2014; 118:10576-87. [PMID: 25144917 DOI: 10.1021/jp504820w] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The presence of heterogeneity in the interdomain arrangement of several biomolecules is required for their function. Here we present a method to obtain crucial clues to distinguish between different kinds of protein conformational distributions based on experimental NMR data. The method explores subregions of the conformational space and provides both upper and lower bounds of probability for the system to be in each subregion.
Collapse
Affiliation(s)
- Witold Andrałojć
- Center for Magnetic Resonance, University of Florence , Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
| | | | | | | |
Collapse
|
52
|
|
53
|
Kursula P. The many structural faces of calmodulin: a multitasking molecular jackknife. Amino Acids 2014; 46:2295-304. [PMID: 25005783 DOI: 10.1007/s00726-014-1795-y] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 06/22/2014] [Indexed: 12/16/2022]
Abstract
Calmodulin (CaM) is a highly conserved protein and a crucial calcium sensor in eukaryotes. CaM is a regulator of hundreds of diverse target proteins. A wealth of studies has been carried out on the structure of CaM, both in the unliganded form and in complexes with target proteins and peptides. The outcome of these studies points toward a high propensity to attain various conformational states, depending on the binding partner. The purpose of this review is to provide examples of different conformations of CaM trapped in the crystal state. In addition, comparisons are made to corresponding studies in solution. The different CaM conformations in crystal structures are also compared based on the positions of the metal ions bound to their EF hands, in terms of distances, angles, and pseudo-torsion angles. Possible caveats and artifacts in CaM crystal structures are discussed, as well as the possibilities of trapping biologically relevant CaM conformations in the crystal state.
Collapse
Affiliation(s)
- Petri Kursula
- Faculty of Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland,
| |
Collapse
|
54
|
Rinaldelli M, Ravera E, Calderone V, Parigi G, Murshudov GN, Luchinat C. Simultaneous use of solution NMR and X-ray data in REFMAC5 for joint refinement/detection of structural differences. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2014; 70:958-67. [PMID: 24699641 PMCID: PMC4306559 DOI: 10.1107/s1399004713034160] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 12/18/2013] [Indexed: 11/12/2022]
Abstract
The program REFMAC5 from CCP4 was modified to allow the simultaneous use of X-ray crystallographic data and paramagnetic NMR data (pseudocontact shifts and self-orientation residual dipolar couplings) and/or diamagnetic residual dipolar couplings. Incorporation of these long-range NMR restraints in REFMAC5 can reveal differences between solid-state and solution conformations of molecules or, in their absence, can be used together with X-ray crystallographic data for structural refinement. Since NMR and X-ray data are complementary, when a single structure is consistent with both sets of data and still maintains reasonably `ideal' geometries, the reliability of the derived atomic model is expected to increase. The program was tested on five different proteins: the catalytic domain of matrix metalloproteinase 1, GB3, ubiquitin, free calmodulin and calmodulin complexed with a peptide. In some cases the joint refinement produced a single model consistent with both sets of observations, while in other cases it indicated, outside the experimental uncertainty, the presence of different protein conformations in solution and in the solid state.
Collapse
Affiliation(s)
- Mauro Rinaldelli
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy
- Department of Chemistry ‘Ugo Schiff’, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Enrico Ravera
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy
- Department of Chemistry ‘Ugo Schiff’, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Vito Calderone
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy
- Department of Chemistry ‘Ugo Schiff’, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Giacomo Parigi
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy
- Department of Chemistry ‘Ugo Schiff’, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Garib N. Murshudov
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, England
| | - Claudio Luchinat
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy
- Department of Chemistry ‘Ugo Schiff’, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| |
Collapse
|
55
|
Ferella L, Luchinat C, Ravera E, Rosato A. SedNMR: a web tool for optimizing sedimentation of macromolecular solutes for SSNMR. JOURNAL OF BIOMOLECULAR NMR 2013; 57:319-26. [PMID: 24243317 DOI: 10.1007/s10858-013-9795-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Accepted: 11/11/2013] [Indexed: 05/09/2023]
Abstract
We have proposed solid state NMR (SSNMR) of sedimented solutes as a novel approach to sample preparation for biomolecular SSNMR without crystallization or other sample manipulations. The biomolecules are confined by high gravity--obtained by centrifugal forces either directly in a SSNMR rotor or in a ultracentrifugal device--into a hydrated non-crystalline solid suitable for SSNMR investigations. When gravity is removed, the sample reverts to solution and can be treated as any solution NMR sample. We here describe a simple web tool to calculate the relevant parameters for the success of the experiment.
Collapse
Affiliation(s)
- Lucio Ferella
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, FI, Italy
| | | | | | | |
Collapse
|
56
|
Russo L, Maestre-Martinez M, Wolff S, Becker S, Griesinger C. Interdomain dynamics explored by paramagnetic NMR. J Am Chem Soc 2013; 135:17111-20. [PMID: 24111622 DOI: 10.1021/ja408143f] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
An ensemble-based approach is presented to explore the conformational space sampled by a multidomain protein showing moderate interdomain dynamics in terms of translational and rotational motions. The strategy was applied on a complex of calmodulin (CaM) with the IQ-recognition motif from the voltage-gated calcium channel Ca(v)1.2 (IQ), which adopts three different interdomain orientations in the crystal. The N60D mutant of calmodulin was used to collect pseudocontact shifts and paramagnetically induced residual dipolar couplings for six different lanthanide ions. Then, starting from the crystal structure, pools of conformations were generated by free MD. We found the three crystal conformations in solution, but four additional MD-derived conformations had to be included into the ensemble to fulfill all the paramagnetic data and cross-validate optimally against unused paramagnetic data. Alternative approaches led to similar ensembles. Our "ensemble" approach is a simple and efficient tool to probe and describe the interdomain dynamics and represents a general method that can be used to provide a proper ensemble description of multidomain proteins.
Collapse
Affiliation(s)
- Luigi Russo
- NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry , Am Fassberg 11 37077 Göttingen, Germany
| | | | | | | | | |
Collapse
|
57
|
Fragai M, Luchinat C, Parigi G, Ravera E. Conformational freedom of metalloproteins revealed by paramagnetism-assisted NMR. Coord Chem Rev 2013. [DOI: 10.1016/j.ccr.2013.02.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
58
|
Lorieau JL, Maltsev AS, Louis JM, Bax A. Modulating alignment of membrane proteins in liquid-crystalline and oriented gel media by changing the size and charge of phospholipid bicelles. JOURNAL OF BIOMOLECULAR NMR 2013; 55:369-77. [PMID: 23508769 PMCID: PMC3636151 DOI: 10.1007/s10858-013-9720-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 02/23/2013] [Indexed: 05/21/2023]
Abstract
We demonstrate that alignment of a structured peptide or small protein solubilized in mixed phospholipid:detergent micelles or bicelles, when embedded in a compressed gel or liquid crystalline medium, can be altered by either changing the phospholipid aggregate shape, charge, or both together. For the hemagglutinin fusion peptide solubilized in bicelles, we show that bicelle shape and charge do not change its helical hairpin structure but impact its alignment relative to the alignment medium, both in charged compressed acrylamide gel and in liquid crystalline d(GpG). The method can be used to generate sets of residual dipolar couplings that correspond to orthogonal alignment tensors, and holds promise for high-resolution structural refinement and dynamic mapping of membrane proteins.
Collapse
Affiliation(s)
- Justin L Lorieau
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health, Building 5, Room 126, 9000 Rockville Pike, Bethesda, MD 20892-0520, USA
| | | | | | | |
Collapse
|
59
|
Elgabarty H, Schmieder P, Sebastiani D. Unraveling the existence of dynamic water channels in light-harvesting proteins: alpha-C-phycocyanobilin in vitro. Chem Sci 2013. [DOI: 10.1039/c2sc21145a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
|
60
|
Fry AJ. Computational Studies of Ion Pairing. 7. Ion-Pairing and Association Effects between Tetraalkylammonium Ions and Nitrobenzene Redox Species. “Ion Pairing” to Neutral Substances. J Org Chem 2012. [DOI: 10.1021/jo302385r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Albert J. Fry
- Chemistry Department, Wesleyan University, Middletown, Connecticut 06459,
United States
| |
Collapse
|
61
|
Bertini I, Engelke F, Gonnelli L, Knott B, Luchinat C, Osen D, Ravera E. On the use of ultracentrifugal devices for sedimented solute NMR. JOURNAL OF BIOMOLECULAR NMR 2012; 54:123-7. [PMID: 22872367 DOI: 10.1007/s10858-012-9657-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 07/26/2012] [Indexed: 05/09/2023]
Abstract
We have recently proposed sedimented solute NMR (SedNMR) as a solid-state method to access biomolecules without the need of crystallization or other sample manipulation. The drawback of SedNMR is that samples are intrinsically diluted and this is detrimental for the signal intensity. Ultracentrifugal devices can be used to increase the amount of sample inside the rotor, overcoming the intrinsic sensitivity limitation of the method. We designed two different devices and we here report the directions for using such devices and the relevant equations for determining the parameters for sedimentation.
Collapse
Affiliation(s)
- Ivano Bertini
- Center for Magnetic Resonance (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino, FI, Italy.
| | | | | | | | | | | | | |
Collapse
|
62
|
Kuczera K, Kursula P. Interactions of calmodulin with death-associated protein kinase peptides: experimental and modeling studies. J Biomol Struct Dyn 2012; 30:45-61. [PMID: 22571432 DOI: 10.1080/07391102.2012.674221] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We have studied the interactions between calmodulin (CaM) and three target peptides from the death-associated protein kinase (DAPK) protein family using both experimental and modeling methods, aimed at determining the details of the underlying biological regulation mechanisms. Experimentally, calorimetric binding free energies were determined for the complexes of CaM with peptides representing the DAPK2 wild-type and S308D mutant, as well as DAPK1. The observed affinity of CaM was very similar for all three studied peptides. The DAPK2 and DAPK1 peptides differ significantly in sequence and total charge, while the DAPK2 S308D mutant is designed to model the effects of DAPK2 Ser308 phosphorylation. The crystal structure of the CaM-DAPK2 S308D mutant peptide is also reported. The structures of CaM-DAPK peptide complexes present a mode of CaM-kinase interaction, in which bulky hydrophobic residues at positions 10 and 14 are both bound to the same hydrophobic cleft. To explain the microscopic effects underlying these interactions, we performed free energy calculations based on the approximate MM-PBSA approach. For these highly charged systems, standard MM-PBSA calculations did not yield satisfactory results. We proposed a rational modification of the approach which led to reasonable predictions of binding free energies. All three complexes are strongly stabilized by two effects: electrostatic interactions and buried surface area. The strong favorable interactions are to a large part compensated by unfavorable entropic terms, in which vibrational entropy is the largest contributor. The electrostatic component of the binding free energy followed the trend of the overall peptide charge, with strongest interactions for DAPK1 and weakest for the DAPK2 mutant. The electrostatics was dominated by interactions of the positively charged residues of the peptide with the negatively charged residues of CaM. The nonpolar binding free energy was comparable for all three peptides, the largest contribution coming from the Trp305. About two-thirds of the buried surface area corresponds to nonpolar residues, showing that hydrophobic interactions play an important role in these CaM-peptide complexes. The simulation results agree with the experimental data in predicting a small effect of the S308D mutation on CaM interactions with DAPK2, suggesting that this mutation is not a good model for the S308 phosphorylation.
Collapse
Affiliation(s)
- Krzysztof Kuczera
- Departments of Chemistry and Biochemistry, University of Kansas, Lawrence, KS, 66045, USA.
| | | |
Collapse
|
63
|
Nagulapalli M, Parigi G, Yuan J, Gsponer J, Deraos G, Bamm VV, Harauz G, Matsoukas J, de Planque MRR, Gerothanassis IP, Babu MM, Luchinat C, Tzakos AG. Recognition pliability is coupled to structural heterogeneity: a calmodulin intrinsically disordered binding region complex. Structure 2012; 20:522-33. [PMID: 22405011 DOI: 10.1016/j.str.2012.01.021] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 12/01/2011] [Accepted: 01/03/2012] [Indexed: 11/18/2022]
Abstract
Protein interactions within regulatory networks should adapt in a spatiotemporal-dependent dynamic environment, in order to process and respond to diverse and versatile cellular signals. However, the principles governing recognition pliability in protein complexes are not well understood. We have investigated a region of the intrinsically disordered protein myelin basic protein (MBP(145-165)) that interacts with calmodulin, but that also promiscuously binds other biomolecules (membranes, modifying enzymes). To characterize this interaction, we implemented an NMR spectroscopic approach that calculates, for each conformation of the complex, the maximum occurrence based on recorded pseudocontact shifts and residual dipolar couplings. We found that the MBP(145-165)-calmodulin interaction is characterized by structural heterogeneity. Quantitative comparative analysis indicated that distinct conformational landscapes of structural heterogeneity are sampled for different calmodulin-target complexes. Such structural heterogeneity in protein complexes could potentially explain the way that transient and promiscuous protein interactions are optimized and tuned in complex regulatory networks.
Collapse
Affiliation(s)
- Malini Nagulapalli
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
64
|
Bertini I, Luchinat C, Nagulapalli M, Parigi G, Ravera E. Paramagnetic relaxation enhancement for the characterization of the conformational heterogeneity in two-domain proteins. Phys Chem Chem Phys 2012; 14:9149-56. [PMID: 22622816 DOI: 10.1039/c2cp40139h] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Multidomain proteins are often composed of rigid domains that can reorient in solution more or less freely. Calmodulin (CaM) is a two domain protein which can experience a large degree of conformational freedom thanks to a mobile linker connecting the N-terminal and C-terminal domains of the protein. The maximum occurrences (MOs) of the possible protein conformations have been analyzed using the paramagnetic relaxation enhancements (PREs) induced by a gadolinium(III) ion together with the paramagnetic pseudocontact shift and residual dipolar coupling restraints measured in the presence of terbium(III), thulium(III) or dysprosium(III) ions. The results suggest that the PREs provide complementary information useful for improving the description of the conformational heterogeneity of the protein. The data, acquired at 298 K and at 278 K, suggest that compact conformations are disfavoured by decreasing the temperature.
Collapse
Affiliation(s)
- Ivano Bertini
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy.
| | | | | | | | | |
Collapse
|
65
|
Kobashigawa Y, Saio T, Ushio M, Sekiguchi M, Yokochi M, Ogura K, Inagaki F. Convenient method for resolving degeneracies due to symmetry of the magnetic susceptibility tensor and its application to pseudo contact shift-based protein-protein complex structure determination. JOURNAL OF BIOMOLECULAR NMR 2012; 53:53-63. [PMID: 22487935 PMCID: PMC3351616 DOI: 10.1007/s10858-012-9623-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 03/27/2012] [Indexed: 05/14/2023]
Abstract
Pseudo contact shifts (PCSs) induced by paramagnetic lanthanide ions fixed in a protein frame provide long-range distance and angular information, and are valuable for the structure determination of protein-protein and protein-ligand complexes. We have been developing a lanthanide-binding peptide tag (hereafter LBT) anchored at two points via a peptide bond and a disulfide bond to the target proteins. However, the magnetic susceptibility tensor displays symmetry, which can cause multiple degenerated solutions in a structure calculation based solely on PCSs. Here we show a convenient method for resolving this degeneracy by changing the spacer length between the LBT and target protein. We applied this approach to PCS-based rigid body docking between the FKBP12-rapamycin complex and the mTOR FRB domain, and demonstrated that degeneracy could be resolved using the PCS restraints obtained from two-point anchored LBT with two different spacer lengths. The present strategy will markedly increase the usefulness of two-point anchored LBT for protein complex structure determination.
Collapse
Affiliation(s)
- Yoshihiro Kobashigawa
- Department of Structural Biology, Faculty of Advanced Life Science, Hokkaido University, N-21, W-11, Kita-ku, Sapporo, 001-0021 Japan
| | - Tomohide Saio
- Department of Structural Biology, Faculty of Advanced Life Science, Hokkaido University, N-21, W-11, Kita-ku, Sapporo, 001-0021 Japan
| | - Masahiro Ushio
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Mitsuhiro Sekiguchi
- Analysis and Pharmacokinetics Research Labs, Department of Drug Discovery, Astellas Pharma Inc., Tokyo, Japan
| | - Masashi Yokochi
- Department of Structural Biology, Faculty of Advanced Life Science, Hokkaido University, N-21, W-11, Kita-ku, Sapporo, 001-0021 Japan
| | - Kenji Ogura
- Department of Structural Biology, Faculty of Advanced Life Science, Hokkaido University, N-21, W-11, Kita-ku, Sapporo, 001-0021 Japan
| | - Fuyuhiko Inagaki
- Department of Structural Biology, Faculty of Advanced Life Science, Hokkaido University, N-21, W-11, Kita-ku, Sapporo, 001-0021 Japan
| |
Collapse
|
66
|
Piazza M, Futrega K, Spratt DE, Dieckmann T, Guillemette JG. Structure and dynamics of calmodulin (CaM) bound to nitric oxide synthase peptides: effects of a phosphomimetic CaM mutation. Biochemistry 2012; 51:3651-61. [PMID: 22486744 DOI: 10.1021/bi300327z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nitric oxide synthase (NOS) plays a major role in a number of key physiological and pathological processes. Knowledge of how this is regulated is important. The small acidic calcium binding protein, calmodulin (CaM), is required to fully activate the enzyme. The exact mechanism of how CaM activates NOS is not fully understood. Studies have shown CaM to act like a switch that causes a conformational change in NOS to allow for the transfer of an electron between the reductase and oxygenase domains through a process that is thought to be highly dynamic. To investigate the dynamic properties of CaM-NOS interactions, we determined the solution structure of CaM bound to the inducible NOS (iNOS) and endothelial NOS (eNOS) CaM binding region peptides. In addition, we investigated the effect of CaM phosphorylation. Tyrosine 99 (Y99) of CaM is reported to be phosphorylated in vivo. We have produced a phosphomimetic Y99E CaM to investigate the structural and functional effects that the phosphorylation of this residue may have on nitric oxide production. All three mammalian NOS isoforms were included in the investigation. Our results show that a phosphomimetic Y99E CaM significantly reduces the maximal synthase activity of eNOS by 40% while having little effect on nNOS or iNOS activity. A comparative nuclear magnetic resonance study between phosphomimetic Y99E CaM and wild-type CaM bound to the eNOS CaM binding region peptide was performed. This investigation provides important insights into how the increased electronegativity of a phosphorylated CaM protein affects the binding, dynamics, and activation of the NOS enzymes.
Collapse
Affiliation(s)
- Michael Piazza
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | | | | | | | | |
Collapse
|
67
|
Luchinat C, Parigi G, Ravera E, Rinaldelli M. Solid-state NMR crystallography through paramagnetic restraints. J Am Chem Soc 2012; 134:5006-9. [PMID: 22393876 DOI: 10.1021/ja210079n] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pseudocontact shifts (PCSs) measured by solid-state NMR spectroscopy (SS-NMR) on microcrystalline powders of a paramagnetic metalloprotein permit NMR crystallography. Along with other restraints for SS-NMR experiments, the protein molecular structure as well as the correct crystal packing are obtained.
Collapse
Affiliation(s)
- Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, via Sacconi 6, Sesto Fiorentino, Italy.
| | | | | | | |
Collapse
|
68
|
Luchinat C, Nagulapalli M, Parigi G, Sgheri L. Maximum occurrence analysis of protein conformations for different distributions of paramagnetic metal ions within flexible two-domain proteins. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 215:85-93. [PMID: 22264683 DOI: 10.1016/j.jmr.2011.12.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Revised: 12/14/2011] [Accepted: 12/18/2011] [Indexed: 05/31/2023]
Abstract
Multidomain proteins are composed of rigid domains connected by (flexible) linkers. Therefore, the domains may experience a large degree of reciprocal reorientation. Pseudocontact shifts and residual dipolar couplings arising from one or more paramagnetic metals successively placed in a single metal binding site in the protein can be used as restraints to assess the degree of mobility of the different domains. They can be used to determine the maximum occurrence (MO) of each possible protein conformation, i.e. the maximum weight that such conformations can have independently of the real structural ensemble, in agreement with the provided restraints. In the case of two-domain proteins, the metal ions can be placed all in the same domain, or distributed between the two domains. It has been demonstrated that the quantity of independent information for the characterization of the system is larger when all metals are bound in the same domain. At the same time, it has been shown that there are practical advantages in placing the metals in different domains. Here, it is shown that distributing the metals between the domains provides a tool for defining a coefficient of compatibility among the restraints obtained from different metals, without a significant decrease of the capability of the MO values to discriminate among conformations with different weights.
Collapse
Affiliation(s)
- Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy.
| | | | | | | |
Collapse
|
69
|
Schmitz C, Vernon R, Otting G, Baker D, Huber T. Protein structure determination from pseudocontact shifts using ROSETTA. J Mol Biol 2012; 416:668-77. [PMID: 22285518 DOI: 10.1016/j.jmb.2011.12.056] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 12/16/2011] [Accepted: 12/27/2011] [Indexed: 11/25/2022]
Abstract
Paramagnetic metal ions generate pseudocontact shifts (PCSs) in nuclear magnetic resonance spectra that are manifested as easily measurable changes in chemical shifts. Metals can be incorporated into proteins through metal binding tags, and PCS data constitute powerful long-range restraints on the positions of nuclear spins relative to the coordinate system of the magnetic susceptibility anisotropy tensor (Δχ-tensor) of the metal ion. We show that three-dimensional structures of proteins can reliably be determined using PCS data from a single metal binding site combined with backbone chemical shifts. The program PCS-ROSETTA automatically determines the Δχ-tensor and metal position from the PCS data during the structure calculations, without any prior knowledge of the protein structure. The program can determine structures accurately for proteins of up to 150 residues, offering a powerful new approach to protein structure determination that relies exclusively on readily measurable backbone chemical shifts and easily discriminates between correctly and incorrectly folded conformations.
Collapse
Affiliation(s)
- Christophe Schmitz
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia
| | | | | | | | | |
Collapse
|
70
|
Bianconi A, Ciasca G, Tenenbaum A, Battisti A, Campi G. Temperature and solvent dependence of the dynamical landscape of tau protein conformations. J Biol Phys 2012; 38:169-79. [PMID: 23277677 PMCID: PMC3285732 DOI: 10.1007/s10867-011-9244-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 10/18/2011] [Indexed: 02/05/2023] Open
Abstract
We report the variation with temperature of the ensemble distribution of conformations spanned by the tau protein in its dynamical states measured by small-angle X-ray scattering (SAXS) using synchrotron radiation. The SAXS data show a clear temperature variation of the distribution of occupied protein conformations from 293 to 318 K. More conformations with a smaller radius of gyration are occupied at higher temperature. The protein-solvent interactions are shown by computer simulation to be essential for controlling the dynamics of protein conformations, providing evidence for the key role of water solvent in the protein dynamics, as proposed by Giorgio Careri.
Collapse
Affiliation(s)
- Antonio Bianconi
- Physics Department, Sapienza University of Rome, Piazzale A. Moro 2, 00185 Roma, Italy
| | - Gabriele Ciasca
- Physics Department, Sapienza University of Rome, Piazzale A. Moro 2, 00185 Roma, Italy
| | - Alexander Tenenbaum
- Physics Department, Sapienza University of Rome, Piazzale A. Moro 2, 00185 Roma, Italy
| | - Anna Battisti
- Physics Department, University of Trento, Via Sommarive 14, 38123 Povo (Trento), Italy
- LISC, FBK-CMM and University of Trento, Via Sommarive 18, 38123 Povo (Trento), Italy
| | - Gaetano Campi
- CNR, Institute of Crystallography, Via Salaria Km 29.300, 00016 Monterotondo (Roma), Italy
| |
Collapse
|
71
|
Dasgupta S, Hu X, Keizers PHJ, Liu WM, Luchinat C, Nagulapalli M, Overhand M, Parigi G, Sgheri L, Ubbink M. Narrowing the conformational space sampled by two-domain proteins with paramagnetic probes in both domains. JOURNAL OF BIOMOLECULAR NMR 2011; 51:253-263. [PMID: 21826520 DOI: 10.1007/s10858-011-9532-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 07/14/2011] [Indexed: 05/31/2023]
Abstract
Calmodulin is a two-domain protein which in solution can adopt a variety of conformations upon reorientation of its domains. The maximum occurrence (MO) of a set of calmodulin conformations that are representative of the overall conformational space possibly sampled by the protein, has been calculated from the paramagnetism-based restraints. These restraints were measured after inclusion of a lanthanide binding tag in the C-terminal domain to supplement the data obtained by substitution of three paramagnetic lanthanide ions to the calcium ion in the second calcium binding loop of the N-terminal domain. The analysis shows that the availability of paramagnetic restraints arising from metal ions placed on both domains, reduces the MO of the conformations to different extents, thereby helping to identify those conformations that can be mostly sampled by the protein.
Collapse
Affiliation(s)
- Soumyasri Dasgupta
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
72
|
The catalytic domain of MMP-1 studied through tagged lanthanides. FEBS Lett 2011; 586:557-67. [DOI: 10.1016/j.febslet.2011.09.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 09/12/2011] [Accepted: 09/12/2011] [Indexed: 11/22/2022]
|
73
|
Molecular mechanisms of calmodulin action on TRPV5 and modulation by parathyroid hormone. Mol Cell Biol 2011; 31:2845-53. [PMID: 21576356 DOI: 10.1128/mcb.01319-10] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The epithelial Ca(2+) channel transient receptor potential vanilloid 5 (TRPV5) constitutes the apical entry gate for active Ca(2+) reabsorption in the kidney. Ca(2+) influx through TRPV5 induces rapid channel inactivation, preventing excessive Ca(2+) influx. This inactivation is mediated by the last ∼30 residues of the carboxy (C) terminus of the channel. Since the Ca(2+)-sensing protein calmodulin has been implicated in Ca(2+)-dependent regulation of several TRP channels, the potential role of calmodulin in TRPV5 function was investigated. High-resolution nuclear magnetic resonance (NMR) spectroscopy revealed a Ca(2+)-dependent interaction between calmodulin and a C-terminal fragment of TRPV5 (residues 696 to 729) in which one calmodulin binds two TRPV5 C termini. The TRPV5 residues involved in calmodulin binding were mutated to study the functional consequence of releasing calmodulin from the C terminus. The point mutants TRPV5-W702A and TRPV5-R706E, lacking calmodulin binding, displayed a strongly diminished Ca(2+)-dependent inactivation compared to wild-type TRPV5, as demonstrated by patch clamp analysis. Finally, parathyroid hormone (PTH) induced protein kinase A (PKA)-dependent phosphorylation of residue T709, which diminished calmodulin binding to TRPV5 and thereby enhanced channel open probability. The TRPV5-W702A mutant exhibited a significantly increased channel open probability and was not further stimulated by PTH. Thus, calmodulin negatively modulates TRPV5 activity, which is reversed by PTH-mediated channel phosphorylation.
Collapse
|
74
|
Patel AK, Yadav RP, Majava V, Kursula I, Kursula P. Structure of the dimeric autoinhibited conformation of DAPK2, a pro-apoptotic protein kinase. J Mol Biol 2011; 409:369-83. [PMID: 21497605 DOI: 10.1016/j.jmb.2011.03.065] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 03/24/2011] [Accepted: 03/28/2011] [Indexed: 11/27/2022]
Abstract
The death-associated protein kinase (DAPK) family has been characterized as a group of pro-apoptotic serine/threonine kinases that share specific structural features in their catalytic kinase domain. Two of the DAPK family members, DAPK1 and DAPK2, are calmodulin-dependent protein kinases that are regulated by oligomerization, calmodulin binding, and autophosphorylation. In this study, we have determined the crystal and solution structures of murine DAPK2 in the presence of the autoinhibitory domain, with and without bound nucleotides in the active site. The crystal structure shows dimers of DAPK2 in a conformation that is not permissible for protein substrate binding. Two different conformations were seen in the active site upon the introduction of nucleotide ligands. The monomeric and dimeric forms of DAPK2 were further analyzed for solution structure, and the results indicate that the dimers of DAPK2 are indeed formed through the association of two apposed catalytic domains, as seen in the crystal structure. The structures can be further used to build a model for DAPK2 autophosphorylation and to compare with closely related kinases, of which especially DAPK1 is an actively studied drug target. Our structures also provide a model for both homodimerization and heterodimerization of the catalytic domain between members of the DAPK family. The fingerprint of the DAPK family, the basic loop, plays a central role in the dimerization of the kinase domain.
Collapse
Affiliation(s)
- Ashok K Patel
- Department of Biochemistry, University of Oulu, Finland
| | | | | | | | | |
Collapse
|
75
|
|
76
|
Bertini I, Giachetti A, Luchinat C, Parigi G, Petoukhov MV, Pierattelli R, Ravera E, Svergun DI. Conformational space of flexible biological macromolecules from average data. J Am Chem Soc 2010; 132:13553-8. [PMID: 20822180 DOI: 10.1021/ja1063923] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The concept of maximum occurrence (MO), i.e., the maximum percent of time that flexible proteins can spend in any given conformation, is introduced, and a rigorous method is developed to extensively sample the conformational space and to construct MO maps from experimental data. The method is tested in a case study, the flexible two-domain protein calmodulin (CaM), using SAXS and NMR data (i.e., pseudocontact shifts and self-orientation residual dipolar couplings arising from the presence of paramagnetic lanthanide ions), revealing that the "closed" and "fully extended" conformations trapped in the crystalline forms of CaM have MOs of only 5 and 15%, respectively. Compact conformations in general have small MOs, whereas some extended conformations have MO as high as 35%, strongly suggesting these conformations to be most abundant in solution. The method is universally applicable as it requires only standard SAXS data and specific NMR data on lanthanide derivatives of the protein (using native metal sites or lanthanide tagging). The computer program is publicly available using the grid computing infrastructure through the authors' Web portal.
Collapse
Affiliation(s)
- Ivano Bertini
- CERM, University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
77
|
Hass MAS, Keizers PHJ, Blok A, Hiruma Y, Ubbink M. Validation of a lanthanide tag for the analysis of protein dynamics by paramagnetic NMR spectroscopy. J Am Chem Soc 2010; 132:9952-3. [PMID: 20586489 DOI: 10.1021/ja909508r] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Paramagnetic lanthanide tags potentially can enhance the effects of microsecond to millisecond dynamics in proteins on NMR signals and provide structural information on lowly populated states encoded in the pseudocontact shifts. We have investigated the microsecond to millisecond mobility of a two-point attached lanthanide tag, CLaNP-5, using paramagnetic (1)H CPMG relaxation dispersion methods. CLaNP-5 loaded with Lu(3+), Yb(3+), or Tm(3+) was attached to three sites on the surface of two proteins, pseudoazurin and cytochrome c. The paramagnetic center causes large relaxation dispersion effects for two attachment sites, suggesting that local dynamics of the protein at the attachment site causes mobility of the paramagnetic center. At one site the relaxation dispersions are small and limited to the immediate environment of the tag. It is concluded that paramagnetic relaxation dispersion could represent a sensitive method to probe protein dynamics. However, the selection of a rigid attachment site is of critical importance.
Collapse
Affiliation(s)
- Mathias A S Hass
- Leiden University, Institute of Chemistry, Gorlaeus Laboratories, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | | | | | | | | |
Collapse
|
78
|
Schwieters CD, Suh JY, Grishaev A, Ghirlando R, Takayama Y, Clore GM. Solution structure of the 128 kDa enzyme I dimer from Escherichia coli and its 146 kDa complex with HPr using residual dipolar couplings and small- and wide-angle X-ray scattering. J Am Chem Soc 2010; 132:13026-45. [PMID: 20731394 PMCID: PMC2955445 DOI: 10.1021/ja105485b] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The solution structures of free Enzyme I (EI, ∼128 kDa, 575 × 2 residues), the first enzyme in the bacterial phosphotransferase system, and its complex with HPr (∼146 kDa) have been solved using novel methodology that makes use of prior structural knowledge (namely, the structures of the dimeric EIC domain and the isolated EIN domain both free and complexed to HPr), combined with residual dipolar coupling (RDC), small- (SAXS) and wide- (WAXS) angle X-ray scattering and small-angle neutron scattering (SANS) data. The calculational strategy employs conjoined rigid body/torsion/Cartesian simulated annealing, and incorporates improvements in calculating and refining against SAXS/WAXS data that take into account complex molecular shapes in the description of the solvent layer resulting in a better representation of the SAXS/WAXS data. The RDC data orient the symmetrically related EIN domains relative to the C(2) symmetry axis of the EIC dimer, while translational, shape, and size information is provided by SAXS/WAXS. The resulting structures are independently validated by SANS. Comparison of the structures of the free EI and the EI-HPr complex with that of the crystal structure of a trapped phosphorylated EI intermediate reveals large (∼70-90°) hinge body rotations of the two subdomains comprising the EIN domain, as well as of the EIN domain relative to the dimeric EIC domain. These large-scale interdomain motions shed light on the structural transitions that accompany the catalytic cycle of EI.
Collapse
Affiliation(s)
- Charles D. Schwieters
- Division of Computational Biosciences, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892-5624
| | - Jeong-Yong Suh
- Laboratory of Chemical Physics, Building 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, U.S.A
| | - Alexander Grishaev
- Laboratory of Chemical Physics, Building 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, U.S.A
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, Building 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of health, Bethesda, MD 20892-0530, U.S.A
| | - Yuki Takayama
- Laboratory of Chemical Physics, Building 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, U.S.A
| | - G. Marius Clore
- Laboratory of Chemical Physics, Building 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, U.S.A
| |
Collapse
|
79
|
Shapira B, Prestegard JH. Electron-nuclear interactions as probes of domain motion in proteins. J Chem Phys 2010; 132:115102. [PMID: 20331317 DOI: 10.1063/1.3328644] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Long range interactions between nuclear spins and paramagnetic ions can serve as a sensitive monitor of internal motion of various parts of proteins, including functional loops and separate domains. In the case of interdomain motion, the interactions between the ion and NMR-observable nuclei are modulated in direction and magnitude mainly by a combination of overall and interdomain motions. The effects on observable parameters such as paramagnetic relaxation enhancement (PRE) and pseudocontact shift (PCS) can, in principle, be used to characterize motion. These parameters are frequently used for the purpose of structural refinements. However, their use to probe actual domain motions is less common and is lacking a proper theoretical treatment from a motional perspective. In this work, a suitable spin Hamiltonian is incorporated in a two body diffusion model to produce the time correlation function for the nuclear spin-paramagnetic ion interactions. Simulated observables for nuclei in different positions with respect to the paramagnetic ion are produced. Based on these simulations, it demonstrated that both the PRE and the PCS can be very sensitive probes of domain motion. Results for different nuclei within the protein sense different aspects of the motions. Some are more sensitive to the amplitude of the internal motion, others are more sensitive to overall diffusion rates, allowing separation of these contributions. Experimentally, the interaction strength can also be tuned by substitution of different paramagnetic ions or by varying magnetic field strength (in the case of lanthanides) to allow the use of more detailed diffusion models without reducing the reliability of data fitting.
Collapse
Affiliation(s)
- Boaz Shapira
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602, USA
| | | |
Collapse
|
80
|
Duan L, Liu W, Wang ZJ, Liang AH, Yang BS. Critical role of tyrosine 79 in the fluorescence resonance energy transfer and terbium(III)-dependent self-assembly of ciliate Euplotes octocarinatus centrin. J Biol Inorg Chem 2010; 15:995-1007. [DOI: 10.1007/s00775-010-0660-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 04/11/2010] [Indexed: 11/30/2022]
|
81
|
Saio T, Yokochi M, Kumeta H, Inagaki F. PCS-based structure determination of protein-protein complexes. JOURNAL OF BIOMOLECULAR NMR 2010; 46:271-80. [PMID: 20300805 PMCID: PMC2844537 DOI: 10.1007/s10858-010-9401-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 02/17/2010] [Indexed: 05/03/2023]
Abstract
A simple and fast nuclear magnetic resonance method for docking proteins using pseudo-contact shift (PCS) and (1)H(N)/(15)N chemical shift perturbation is presented. PCS is induced by a paramagnetic lanthanide ion that is attached to a target protein using a lanthanide binding peptide tag anchored at two points. PCS provides long-range (approximately 40 A) distance and angular restraints between the lanthanide ion and the observed nuclei, while the (1)H(N)/(15)N chemical shift perturbation data provide loose contact-surface information. The usefulness of this method was demonstrated through the structure determination of the p62 PB1-PB1 complex, which forms a front-to-back 20 kDa homo-oligomer. As p62 PB1 does not intrinsically bind metal ions, the lanthanide binding peptide tag was attached to one subunit of the dimer at two anchoring points. Each monomer was treated as a rigid body and was docked based on the backbone PCS and backbone chemical shift perturbation data. Unlike NOE-based structural determination, this method only requires resonance assignments of the backbone (1)H(N)/(15)N signals and the PCS data obtained from several sets of two-dimensional (15)N-heteronuclear single quantum coherence spectra, thus facilitating rapid structure determination of the protein-protein complex.
Collapse
Affiliation(s)
- Tomohide Saio
- Graduate School of Life Science, Hokkaido University, Sapporo, 001-0021 Japan
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, 001-0021 Japan
| | - Masashi Yokochi
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, 001-0021 Japan
| | - Hiroyuki Kumeta
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, 001-0021 Japan
| | - Fuyuhiko Inagaki
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, 001-0021 Japan
| |
Collapse
|
82
|
Man B, Su XC, Liang H, Simonsen S, Huber T, Messerle B, Otting G. 3-Mercapto-2,6-Pyridinedicarboxylic Acid: A Small Lanthanide-Binding Tag for Protein Studies by NMR Spectroscopy. Chemistry 2010; 16:3827-32. [DOI: 10.1002/chem.200902904] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
83
|
Simon B, Madl T, Mackereth C, Nilges M, Sattler M. An Efficient Protocol for NMR-Spectroscopy-Based Structure Determination of Protein Complexes in Solution. Angew Chem Int Ed Engl 2010; 49:1967-70. [DOI: 10.1002/anie.200906147] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
84
|
Simon B, Madl T, Mackereth C, Nilges M, Sattler M. An Efficient Protocol for NMR-Spectroscopy-Based Structure Determination of Protein Complexes in Solution. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.200906147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
85
|
Häussinger D, Huang JR, Grzesiek S. DOTA-M8: An extremely rigid, high-affinity lanthanide chelating tag for PCS NMR spectroscopy. J Am Chem Soc 2010; 131:14761-7. [PMID: 19785413 DOI: 10.1021/ja903233w] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new lanthanide chelating tag (M8) for paramagnetic labeling of biomolecules is presented, which is based on an eight-fold, stereoselectively methyl-substituted DOTA that can be covalently linked to the host molecule by a single disulfide bond. The steric overcrowding of the DOTA scaffold leads to an extremely rigid, kinetically and chemically inert lanthanide chelator. Its steric bulk restricts the motion of the tag relative to the host molecule. These properties result in very large pseudocontact shifts (>5 ppm) and residual dipolar couplings (>20 Hz) for Dy-M8 linked to ubiquitin, which are unprecedented for a small, single-point-attachment tag. Such large pseudocontact shifts should be well detectable even for larger proteins and distances beyond approximately 50 A. Due to its exceptionally high stability and lanthanide affinity M8 can be used under extreme chemical or physical conditions, such as those applied for protein denaturation, or when it is undesirable that buffer or protein react with excess lanthanide ions.
Collapse
Affiliation(s)
- Daniel Häussinger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland.
| | | | | |
Collapse
|
86
|
Myllykoski M, Kuczera K, Kursula P. Complex formation between calmodulin and a peptide from the intracellular loop of the gap junction protein connexin43: Molecular conformation and energetics of binding. Biophys Chem 2009; 144:130-5. [PMID: 19716642 DOI: 10.1016/j.bpc.2009.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 07/31/2009] [Accepted: 08/01/2009] [Indexed: 11/18/2022]
Abstract
Gap junctions are formed by a family of transmembrane proteins, connexins. Connexin43 is a widely studied member of the family, being ubiquitously expressed in a variety of tissues and a target of a large number of disease mutations. The intracellular loop of connexin43 has been shown to include a calmodulin binding domain, but detailed 3-dimensional data on the structure of the complex are not available. In this study, we used a synthetic peptide from this domain to reveal the conformation of the calmodulin-peptide complex by small angle X-ray scattering. Upon peptide binding, calmodulin lost its dumbbell shape, adopting a more globular conformation. We also studied the energetics of the interaction using calorimetry and computational methods. All our data indicate that calmodulin binds to the peptide from cx43 in the classical 'collapsed' conformation.
Collapse
Affiliation(s)
- Matti Myllykoski
- Department of Biochemistry, FIN-90014, University of Oulu, Oulu, Finland
| | | | | |
Collapse
|
87
|
Su XC, Liang H, Loscha KV, Otting G. [Ln(DPA)3]3− Is a Convenient Paramagnetic Shift Reagent for Protein NMR Studies. J Am Chem Soc 2009; 131:10352-3. [DOI: 10.1021/ja9034957] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xun-Cheng Su
- Research School of Chemistry, Australian National University, Canberra, Australia
| | - Haobo Liang
- Research School of Chemistry, Australian National University, Canberra, Australia
| | - Karin V. Loscha
- Research School of Chemistry, Australian National University, Canberra, Australia
| | - Gottfried Otting
- Research School of Chemistry, Australian National University, Canberra, Australia
| |
Collapse
|