PubRank

Ivano Bertini

Author PubWeight™ 188.82‹?›

Top papers

Rank Title Journal Year PubWeight™‹?›
1 Metal ions in biological catalysis: from enzyme databases to general principles. J Biol Inorg Chem 2008 2.87
2 The Atx1-Ccc2 complex is a metal-mediated protein-protein interaction. Nat Chem Biol 2006 2.56
3 Counting the zinc-proteins encoded in the human genome. J Proteome Res 2006 2.38
4 Metal-free superoxide dismutase forms soluble oligomers under physiological conditions: a possible general mechanism for familial ALS. Proc Natl Acad Sci U S A 2007 2.16
5 Zinc through the three domains of life. J Proteome Res 2006 2.11
6 Evidence of different metabolic phenotypes in humans. Proc Natl Acad Sci U S A 2008 2.06
7 Solution structure of Sco1: a thioredoxin-like protein Involved in cytochrome c oxidase assembly. Structure 2003 2.01
8 The unusually stable quaternary structure of human Cu,Zn-superoxide dismutase 1 is controlled by both metal occupancy and disulfide status. J Biol Chem 2004 1.97
9 Perspectives on NMR in drug discovery: a technique comes of age. Nat Rev Drug Discov 2008 1.95
10 Affinity gradients drive copper to cellular destinations. Nature 2010 1.82
11 Folding studies of Cox17 reveal an important interplay of cysteine oxidation and copper binding. Structure 2005 1.81
12 Metallochaperones and metal-transporting ATPases: a comparative analysis of sequences and structures. Genome Res 2002 1.80
13 MIA40 is an oxidoreductase that catalyzes oxidative protein folding in mitochondria. Nat Struct Mol Biol 2009 1.60
14 Protonless NMR experiments for sequence-specific assignment of backbone nuclei in unfolded proteins. J Am Chem Soc 2006 1.54
15 Metalloproteomes: a bioinformatic approach. Acc Chem Res 2009 1.52
16 A copper(I) protein possibly involved in the assembly of CuA center of bacterial cytochrome c oxidase. Proc Natl Acad Sci U S A 2005 1.52
17 NMR reveals pathway for ferric mineral precursors to the central cavity of ferritin. Proc Natl Acad Sci U S A 2009 1.48
18 Structure of human Wilson protein domains 5 and 6 and their interplay with domain 4 and the copper chaperone HAH1 in copper uptake. Proc Natl Acad Sci U S A 2006 1.47
19 A redox switch in CopC: an intriguing copper trafficking protein that binds copper(I) and copper(II) at different sites. Proc Natl Acad Sci U S A 2003 1.46
20 Solution structure of Apo Cu,Zn superoxide dismutase: role of metal ions in protein folding. Biochemistry 2003 1.44
21 Acycloguanosyl 5'-thymidyltriphosphate, a thymidine analogue prodrug activated by telomerase, reduces pancreatic tumor growth in mice. Gastroenterology 2010 1.44
22 Metabolomics: available results, current research projects in breast cancer, and future applications. J Clin Oncol 2007 1.42
23 Solution structure of human beta-parvalbumin and structural comparison with its paralog alpha-parvalbumin and with their rat orthologs. Biochemistry 2004 1.41
24 A large dust/ice ratio in the nucleus of comet 9P/Tempel 1. Nature 2005 1.40
25 Solution structure and intermolecular interactions of the third metal-binding domain of ATP7A, the Menkes disease protein. J Biol Chem 2006 1.40
26 Italy must invest more in science and technology. Nature 2008 1.38
27 Individual human phenotypes in metabolic space and time. J Proteome Res 2009 1.29
28 SOD1 and amyotrophic lateral sclerosis: mutations and oligomerization. PLoS One 2008 1.27
29 A novel intermembrane space-targeting signal docks cysteines onto Mia40 during mitochondrial oxidative folding. J Cell Biol 2009 1.26
30 A hint to search for metalloproteins in gene banks. Bioinformatics 2004 1.25
31 Occurrence of copper proteins through the three domains of life: a bioinformatic approach. J Proteome Res 2007 1.24
32 13C direct detection experiments on the paramagnetic oxidized monomeric copper, zinc superoxide dismutase. J Am Chem Soc 2003 1.23
33 Metal-MACiE: a database of metals involved in biological catalysis. Bioinformatics 2009 1.23
34 A hint for the function of human Sco1 from different structures. Proc Natl Acad Sci U S A 2006 1.23
35 Complete assignment of heteronuclear protein resonances by protonless NMR spectroscopy. Angew Chem Int Ed Engl 2005 1.22
36 Fast resonance assignment and fold determination of human superoxide dismutase by high-resolution proton-detected solid-state MAS NMR spectroscopy. Angew Chem Int Ed Engl 2011 1.21
37 A structural-dynamical characterization of human Cox17. J Biol Chem 2007 1.20
38 Metal binding domains 3 and 4 of the Wilson disease protein: solution structure and interaction with the copper(I) chaperone HAH1. Biochemistry 2008 1.18
39 Cellular copper distribution: a mechanistic systems biology approach. Cell Mol Life Sci 2010 1.18
40 Mechanism of Cu(A) assembly. Nat Chem Biol 2008 1.17
41 Solid-state NMR spectroscopy of a paramagnetic protein: assignment and study of human dimeric oxidized CuII-ZnII superoxide dismutase (SOD). Angew Chem Int Ed Engl 2007 1.17
42 Molecular chaperone function of Mia40 triggers consecutive induced folding steps of the substrate in mitochondrial protein import. Proc Natl Acad Sci U S A 2010 1.16
43 Paramagnetism-based restraints for Xplor-NIH. J Biomol NMR 2004 1.15
44 Solution structure of CopC: a cupredoxin-like protein involved in copper homeostasis. Structure 2002 1.15
45 Standard operating procedures for pre-analytical handling of blood and urine for metabolomic studies and biobanks. J Biomol NMR 2011 1.15
46 High-field dynamic nuclear polarization with high-spin transition metal ions. J Am Chem Soc 2011 1.15
47 Molecular recognition and substrate mimicry drive the electron-transfer process between MIA40 and ALR. Proc Natl Acad Sci U S A 2011 1.14
48 A method for C(alpha) direct-detection in protonless NMR. J Magn Reson 2007 1.13
49 Solution structure of the apo and copper(I)-loaded human metallochaperone HAH1. Biochemistry 2004 1.13
50 Structural and dynamic aspects related to oligomerization of apo SOD1 and its mutants. Proc Natl Acad Sci U S A 2009 1.12
51 Cyanobacterial metallochaperone inhibits deleterious side reactions of copper. Proc Natl Acad Sci U S A 2011 1.12
52 Human SOD1 before harboring the catalytic metal: solution structure of copper-depleted, disulfide-reduced form. J Biol Chem 2005 1.12
53 Structural model for an alkaline form of ferricytochrome C. J Am Chem Soc 2003 1.11
54 A structural characterization of human SCO2. Structure 2007 1.11
55 Mitochondrial copper(I) transfer from Cox17 to Sco1 is coupled to electron transfer. Proc Natl Acad Sci U S A 2008 1.11
56 Structure and backbone dynamics of a microcrystalline metalloprotein by solid-state NMR. Proc Natl Acad Sci U S A 2012 1.10
57 The coiled coil-helix-coiled coil-helix proteins may be redox proteins. FEBS Lett 2009 1.09
58 Human Sco1 functional studies and pathological implications of the P174L mutant. Proc Natl Acad Sci U S A 2006 1.08
59 Structural analysis of metal sites in proteins: non-heme iron sites as a case study. J Mol Biol 2009 1.06
60 Structural characterization of CHCHD5 and CHCHD7: two atypical human twin CX9C proteins. J Struct Biol 2012 1.06
61 Fully metallated S134N Cu,Zn-superoxide dismutase displays abnormal mobility and intermolecular contacts in solution. J Biol Chem 2005 1.05
62 Structure and dynamics of copper-free SOD: The protein before binding copper. Protein Sci 2002 1.04
63 An NMR study of the interaction of the N-terminal cytoplasmic tail of the Wilson disease protein with copper(I)-HAH1. J Biol Chem 2009 1.04
64 Paramagnetically induced residual dipolar couplings for solution structure determination of lanthanide binding proteins. J Am Chem Soc 2002 1.04
65 The G-triplex DNA. Angew Chem Int Ed Engl 2013 1.04
66 A docking approach to the study of copper trafficking proteins; interaction between metallochaperones and soluble domains of copper ATPases. Structure 2004 1.03
67 A bioinformatics view of zinc enzymes. J Inorg Biochem 2011 1.02
68 Minimal functional sites allow a classification of zinc sites in proteins. PLoS One 2011 1.02
69 Understanding copper trafficking in bacteria: interaction between the copper transport protein CopZ and the N-terminal domain of the copper ATPase CopA from Bacillus subtilis. Biochemistry 2003 1.02
70 Atomic-resolution monitoring of protein maturation in live human cells by NMR. Nat Chem Biol 2013 1.01
71 Superoxide dismutase folding/unfolding pathway: role of the metal ions in modulating structural and dynamical features. J Mol Biol 2003 1.01
72 An NMR study of the interaction between the human copper(I) chaperone and the second and fifth metal-binding domains of the Menkes protein. FEBS J 2005 1.00
73 Solution structures of a cyanobacterial metallochaperone: insight into an atypical copper-binding motif. J Biol Chem 2004 1.00
74 Solution structure of Cox11, a novel type of beta-immunoglobulin-like fold involved in CuB site formation of cytochrome c oxidase. J Biol Chem 2004 1.00
75 Probing the interaction of cisplatin with the human copper chaperone Atox1 by solution and in-cell NMR spectroscopy. J Am Chem Soc 2011 0.99
76 The functions of Sco proteins from genome-based analysis. J Proteome Res 2007 0.99
77 The evolutionarily conserved trimeric structure of CutA1 proteins suggests a role in signal transduction. J Biol Chem 2003 0.99
78 Dynamic properties of the G93A mutant of copper-zinc superoxide dismutase as detected by NMR spectroscopy: implications for the pathology of familial amyotrophic lateral sclerosis. Biochemistry 2003 0.98
79 A new zinc-protein coordination site in intracellular metal trafficking: solution structure of the Apo and Zn(II) forms of ZntA(46-118). J Mol Biol 2002 0.98
80 The delivery of copper for thylakoid import observed by NMR. Proc Natl Acad Sci U S A 2006 0.98
81 Solution structure and characterization of the heme chaperone CcmE. Biochemistry 2002 0.98
82 NMR structural analysis of cadmium sensing by winged helix repressor CmtR. J Biol Chem 2007 0.98
83 Solution structure and backbone dynamics of the Cu(I) and apo forms of the second metal-binding domain of the Menkes protein ATP7A. Biochemistry 2004 0.98
84 Speeding up (13)C direct detection biomolecular NMR spectroscopy. J Am Chem Soc 2009 0.98
85 Copper(I)-mediated protein-protein interactions result from suboptimal interaction surfaces. Biochem J 2009 0.97
86 Ortholog search of proteins involved in copper delivery to cytochrome C oxidase and functional analysis of paralogs and gene neighbors by genomic context. J Proteome Res 2005 0.97
87 The different intermolecular interactions of the soluble copper-binding domains of the menkes protein, ATP7A. J Biol Chem 2007 0.96
88 The solution structure of reduced dimeric copper zinc superoxide dismutase. The structural effects of dimerization. Eur J Biochem 2002 0.96
89 Solution structures of the actuator domain of ATP7A and ATP7B, the Menkes and Wilson disease proteins. Biochemistry 2009 0.96
90 Are patients with potential celiac disease really potential? The answer of metabonomics. J Proteome Res 2010 0.95
91 A NMR study of the interaction of a three-domain construct of ATP7A with copper(I) and copper(I)-HAH1: the interplay of domains. J Biol Chem 2005 0.95
92 Paramagnetic shifts in solid-state NMR of proteins to elicit structural information. Proc Natl Acad Sci U S A 2008 0.95
93 Anamorsin is a [2Fe-2S] cluster-containing substrate of the Mia40-dependent mitochondrial protein trapping machinery. Chem Biol 2011 0.95
94 Interaction of cisplatin with human superoxide dismutase. J Am Chem Soc 2012 0.94
95 Structure of nucleophosmin DNA-binding domain and analysis of its complex with a G-quadruplex sequence from the c-MYC promoter. J Biol Chem 2012 0.94
96 Human superoxide dismutase 1 (hSOD1) maturation through interaction with human copper chaperone for SOD1 (hCCS). Proc Natl Acad Sci U S A 2012 0.94
97 Molecular recognition in copper trafficking. Nat Prod Rep 2010 0.93
98 Novel 13C direct detection experiments, including extension to the third dimension, to perform the complete assignment of proteins. J Magn Reson 2005 0.93
99 Exploration of serum metabolomic profiles and outcomes in women with metastatic breast cancer: a pilot study. Mol Oncol 2012 0.92
100 Rapid measurement of pseudocontact shifts in metalloproteins by proton-detected solid-state NMR spectroscopy. J Am Chem Soc 2012 0.92
101 13C- 13C NOESY spectra of a 480 kDa protein: solution NMR of ferritin. J Biomol NMR 2007 0.92
102 An electron-transfer path through an extended disulfide relay system: the case of the redox protein ALR. J Am Chem Soc 2012 0.91
103 An atomic-level investigation of the disease-causing A629P mutant of the Menkes protein, ATP7A. J Mol Biol 2005 0.91
104 Solution structure of the N-terminal domain of a potential copper-translocating P-type ATPase from Bacillus subtilis in the apo and Cu(I) loaded states. J Mol Biol 2002 0.91
105 The characterization and role of zinc binding in yeast Cox4. J Biol Chem 2007 0.91
106 New Type 2 Copper-Cysteinate Proteins. Copper Site Histidine-to-Cysteine Mutants of Yeast Copper-Zinc Superoxide Dismutase. Inorg Chem 1996 0.91
107 Mapping the interaction between the hemophore HasA and its outer membrane receptor HasR using CRINEPT-TROSY NMR spectroscopy. J Am Chem Soc 2009 0.91
108 Structural basis for the function of the N-terminal domain of the ATPase CopA from Bacillus subtilis. J Biol Chem 2003 0.91
109 15N-1H Residual dipolar coupling analysis of native and alkaline-K79A Saccharomyces cerevisiae cytochrome c. Biophys J 2003 0.90
110 Non-heme iron through the three domains of life. Proteins 2007 0.90
111 H-start for exclusively heteronuclear NMR spectroscopy: the case of intrinsically disordered proteins. J Magn Reson 2009 0.90
112 Paramagnetic ions provide structural restraints in solid-state NMR of proteins. J Am Chem Soc 2007 0.90
113 Exclusively heteronuclear NMR experiments to obtain structural and dynamic information on proteins. Chemphyschem 2010 0.90
114 Speeding up sequence specific assignment of IDPs. J Biomol NMR 2012 0.89
115 Direct-detected 13C NMR to investigate the iron(III) hemophore HasA. J Am Chem Soc 2006 0.89
116 Structural and dynamic characterization of intrinsically disordered human securin by NMR spectroscopy. J Am Chem Soc 2008 0.89
117 A strategy for the NMR characterization of type II copper(II) proteins: the case of the copper trafficking protein CopC from Pseudomonas Syringae. J Am Chem Soc 2003 0.88
118 Metabolomic fingerprint of heart failure in humans: a nuclear magnetic resonance spectroscopy analysis. Int J Cardiol 2013 0.88
119 Structural interplay between calcium(II) and copper(II) binding to S100A13 protein. Angew Chem Int Ed Engl 2005 0.88
120 Dynamic nuclear polarization of sedimented solutes. J Am Chem Soc 2013 0.87
121 In vitro fermentation of potential prebiotic flours from natural sources: impact on the human colonic microbiota and metabolome. Mol Nutr Food Res 2012 0.87
122 Transverse-dephasing optimized homonuclear j-decoupling in solid-state NMR spectroscopy of uniformly 13C-labeled proteins. J Am Chem Soc 2009 0.86
123 Seeking the determinants of the elusive functions of Sco proteins. FEBS J 2011 0.86
124 The binding mode of ATP revealed by the solution structure of the N-domain of human ATP7A. J Biol Chem 2009 0.86
125 13C direct detected NMR increases the detectability of residual dipolar couplings. J Am Chem Soc 2006 0.86
126 Structural basis for metal binding specificity: the N-terminal cadmium binding domain of the P1-type ATPase CadA. J Mol Biol 2005 0.85
127 Targeting and maturation of Erv1/ALR in the mitochondrial intermembrane space. ACS Chem Biol 2012 0.85
128 A selective experiment for the sequential protein backbone assignment from 3D heteronuclear spectra. J Magn Reson 2005 0.85
129 A prokaryotic superoxide dismutase paralog lacking two Cu ligands: from largely unstructured in solution to ordered in the crystal. Proc Natl Acad Sci U S A 2005 0.85
130 In-cell NMR in E. coli to monitor maturation steps of hSOD1. PLoS One 2011 0.85
131 A structural and dynamic characterization of the EF-hand protein CLSP. Structure 2006 0.85
132 Paramagnetism-based refinement strategy for the solution structure of human alpha-parvalbumin. Biochemistry 2004 0.84
133 X-ray absorption and NMR spectroscopic studies of CopZ, a copper chaperone in Bacillus subtilis: the coordination properties of the copper ion. Biochemistry 2003 0.84
134 Exclusively heteronuclear (13) C-detected amino-acid-selective NMR experiments for the study of intrinsically disordered proteins (IDPs). Chembiochem 2012 0.84
135 Metalation of the amyotrophic lateral sclerosis mutant glycine 37 to arginine superoxide dismutase (SOD1) apoprotein restores its structural and dynamical properties in solution to those of metalated wild-type SOD1. Biochemistry 2007 0.84
136 Solid-state NMR of matrix metalloproteinase 12: an approach complementary to solution NMR. Chembiochem 2007 0.84
137 The cardiovascular risk of healthy individuals studied by NMR metabonomics of plasma samples. J Proteome Res 2011 0.83
138 Solution structure of the unbound, oxidized Photosystem I subunit PsaC, containing [4Fe-4S] clusters F(A) and F(B): a conformational change occurs upon binding to photosystem I. J Biol Inorg Chem 2002 0.83
139 Direct carbon detection in paramagnetic metalloproteins to further exploit pseudocontact shift restraints. J Am Chem Soc 2004 0.83
140 Molecular view of an electron transfer process essential for iron-sulfur protein biogenesis. Proc Natl Acad Sci U S A 2013 0.83
141 Combination of DQ and ZQ coherences for sensitive through-bond NMR correlation experiments in biosolids under ultra-fast MAS. Chemphyschem 2012 0.82
142 A Systems Biology Approach to Deciphering the Etiology of Steatosis Employing Patient-Derived Dermal Fibroblasts and iPS Cells. Front Physiol 2012 0.82
143 Solution structure of a monoheme ferrocytochrome c from Shewanella putrefaciens and structural analysis of sequence-similar proteins: functional implications. Biochemistry 2002 0.82
144 Catalytic domain of MMP20 (Enamelysin) - the NMR structure of a new matrix metalloproteinase. FEBS Lett 2007 0.82
145 Structural characterization of human S100A16, a low-affinity calcium binder. J Biol Inorg Chem 2010 0.82
146 NMR in structural proteomics and beyond. Prog Nucl Magn Reson Spectrosc 2010 0.82
147 Sco proteins are involved in electron transfer processes. J Biol Inorg Chem 2010 0.82
148 NMR structural analysis of the soluble domain of ZiaA-ATPase and the basis of selective interactions with copper metallochaperone Atx1. J Biol Inorg Chem 2009 0.82
149 A simple protocol for the comparative analysis of the structure and occurrence of biochemical pathways across superkingdoms. J Chem Inf Model 2011 0.81
150 DNP-enhanced MAS NMR of bovine serum albumin sediments and solutions. J Phys Chem B 2014 0.81
151 The unfolding of oxidized c-type cytochromes: the instructive case of Bacillus pasteurii. J Mol Biol 2002 0.81
152 From an inactive prokaryotic SOD homologue to an active protein through site-directed mutagenesis. J Am Chem Soc 2005 0.80
153 Chemical shift-based constraints for solution structure determination of paramagnetic low-spin heme proteins with bis-His and His-CN axial ligands: the cases of oxidized cytochrome b(5) and Met80Ala cyano-cytochrome c. J Biol Inorg Chem 2001 0.80
154 Integration of XAS and NMR techniques for the structure determination of metalloproteins. Examples from the study of copper transport proteins. J Synchrotron Radiat 2004 0.80
155 A further investigation of the cytochrome b5-cytochrome c complex. J Biol Inorg Chem 2003 0.80
156 Bioinformatic comparison of structures and homology-models of matrix metalloproteinases. J Proteome Res 2004 0.80
157 Modeling protein-protein complexes involved in the cytochrome C oxidase copper-delivery pathway. J Proteome Res 2007 0.80
158 NMR characterization of a "fibril-ready" state of demetalated wild-type superoxide dismutase. J Am Chem Soc 2010 0.80
159 The metal reductase activity of some multiheme cytochromes c: NMR structural characterization of the reduction of chromium(VI) to chromium(III) by cytochrome c(7). Proc Natl Acad Sci U S A 2002 0.79
160 Matrix metalloproteinase-inhibitor interaction: the solution structure of the catalytic domain of human matrix metalloproteinase-3 with different inhibitors. J Biol Inorg Chem 2007 0.79
161 Protein stability and mutations in the axial methionine loop of a minimal cytochrome c. J Biol Inorg Chem 2004 0.79
162 A core mutation affecting the folding properties of a soluble domain of the ATPase protein CopA from Bacillus subtilis. J Mol Biol 2003 0.79
163 Individual Reduction Potentials of the Iron Ions in Fe(2)S(2) and High-Potential Fe(4)S(4) Ferredoxins. Inorg Chem 1996 0.79
164 The stability of the cytochrome c scaffold as revealed by NMR spectroscopy. J Inorg Biochem 2004 0.78
165 An intrinsically disordered domain has a dual function coupled to compartment-dependent redox control. J Mol Biol 2012 0.78
166 Comparative analysis of the ADAM and ADAMTS families. J Proteome Res 2005 0.78
167 A quick solution structure determination of the fully oxidized double mutant K9-10A cytochrome c7 from Desulfuromonas acetoxidans and mechanistic implications. J Biomol NMR 2002 0.78
168 Structure-independent cross-validation between residual dipolar couplings originating from internal and external orienting media. J Biomol NMR 2002 0.78
169 Solution structure of apo CopZ from Bacillus subtilis: further analysis of the changes associated with the presence of copper. Biochemistry 2003 0.78
170 Does a fast nuclear magnetic resonance spectroscopy- and X-ray crystallography hybrid approach provide reliable structural information of ligand-protein complexes? A case study of metalloproteinases. J Med Chem 2009 0.78
171 Structure and dynamics of reduced Bacillus pasteurii cytochrome c: oxidation state dependent properties and implications for electron transfer processes. Biochemistry 2003 0.77
172 Dynamics of wild-type HiPIPs: a Cys77Ser mutant and a partially unfolded HiPIP. J Biol Inorg Chem 2002 0.77
173 Zinc proteomes, phylogenetics and evolution. Metallomics 2010 0.77
174 Interaction of the two soluble metal-binding domains of yeast Ccc2 with copper(I)-Atx1. Biochem Biophys Res Commun 2007 0.77
175 Copper exposure effects on yeast mitochondrial proteome. J Proteomics 2011 0.77
176 Cytochrome c and organic molecules: solution structure of the p-aminophenol adduct. Biochemistry 2007 0.77
177 Structural analysis of protein interfaces from 13C direct-detected paramagnetic relaxation enhancements. J Am Chem Soc 2010 0.77
178 Principal component analysis of the conformational freedom within the EF-hand superfamily. J Proteome Res 2005 0.76
179 Copper trafficking in biology: an NMR approach. HFSP J 2009 0.76
180 Structural genomics. Acc Chem Res 2003 0.76
181 Functional role of two interhelical disulfide bonds in human Cox17 protein from a structural perspective. J Biol Chem 2011 0.76
182 Frontiers in solid-state NMR technology. Acc Chem Res 2013 0.76
183 NMR solution structure, backbone mobility, and homology modeling of c-type cytochromes from gram-positive bacteria. Chembiochem 2002 0.76
184 Copper proteomes, phylogenetics and evolution. Metallomics 2010 0.75
185 Spectroscopy: Unexpected interactions. Nature 2011 0.75
186 Backbone-only restraints for fast determination of the protein fold: the role of paramagnetism-based restraints. Cytochrome b562 as an example. J Magn Reson 2005 0.75
187 Direct measurement of dynamic frequency shift induced by cross-correlations in 15N-enriched proteins. Chemphyschem 2004 0.75
188 Metallomics and the cell: some definitions and general comments. Met Ions Life Sci 2013 0.75
189 Erratum: Paramagnetism-based restraints for Xplor-NIH. J Biomol NMR 2004 0.75