IUCrJ最新文献

{"title":"KINNTREX: a neural network to unveil protein mechanisms from time-resolved X-ray crystallography","authors":"Gabriel Biener ,&nbsp;Tek Narsingh Malla ,&nbsp;Peter Schwander ,&nbsp;Marius Schmidt ,&nbsp;T. Ishikawa (Editor)","doi":"10.1107/S2052252524002392","DOIUrl":"10.1107/S2052252524002392","url":null,"abstract":"<div><p>A kinetics-informed neural-network method (KINNTREX) is designed to analyze a time series of difference maps from a time-resolved X-ray crystallographic experiment.</p></div><div><p>Here, a machine-learning method based on a kinetically informed neural network (NN) is introduced. The proposed method is designed to analyze a time series of difference electron-density maps from a time-resolved X-ray crystallographic experiment. The method is named KINNTREX (kinetics-informed NN for time-resolved X-ray crystallography). To validate KINNTREX, multiple realistic scenarios were simulated with increasing levels of complexity. For the simulations, time-resolved X-ray data were generated that mimic data collected from the photocycle of the photoactive yellow protein. KINNTREX only requires the number of intermediates and approximate relaxation times (both obtained from a singular valued decomposition) and does not require an assumption of a candidate mechanism. It successfully predicts a consistent chemical kinetic mechanism, together with difference electron-density maps of the intermediates that appear during the reaction. These features make KINNTREX attractive for tackling a wide range of biomolecular questions. In addition, the versatility of KINNTREX can inspire more NN-based applications to time-resolved data from biological macromolecules obtained by other methods.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 405-422"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140656083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural insights into the molecular mechanism of phytoplasma immunodominant membrane protein","authors":"Chang-Yi Liu ,&nbsp;Han-Pin Cheng ,&nbsp;Chan-Pin Lin ,&nbsp;Yi-Ting Liao ,&nbsp;Tzu-Ping Ko ,&nbsp;Shin-Jen Lin ,&nbsp;Shih-Shun Lin ,&nbsp;Hao-Ching Wang ,&nbsp;Z.-J. Liu (Editor)","doi":"10.1107/S2052252524003075","DOIUrl":"10.1107/S2052252524003075","url":null,"abstract":"<div><p>The first crystal structure of phytoplasma immunodominant membrane protein is reported and structural analysis revealed its potential for actin binding.</p></div><div><p>Immunodominant membrane protein (IMP) is a prevalent membrane protein in phytoplasma and has been confirmed to be an F-actin-binding protein. However, the intricate molecular mechanisms that govern the function of IMP require further elucidation. In this study, the X-ray crystallographic structure of IMP was determined and insights into its interaction with plant actin are provided. A comparative analysis with other proteins demonstrates that IMP shares structural homology with talin rod domain-containing protein 1 (TLNRD1), which also functions as an F-actin-binding protein. Subsequent molecular-docking studies of IMP and F-actin reveal that they possess complementary surfaces, suggesting a stable interaction. The low potential energy and high confidence score of the IMP–F-actin binding model indicate stable binding. Additionally, by employing immunoprecipitation and mass spectrometry, it was discovered that IMP serves as an interaction partner for the phytoplasmal effector causing phyllody 1 (PHYL1). It was then shown that both IMP and PHYL1 are highly expressed in the S2 stage of peanut witches’ broom phytoplasma-infected <em>Catharanthus roseus</em>. The association between IMP and PHYL1 is substantiated through <em>in vivo</em> immunoprecipitation, an <em>in vitro</em> cross-linking assay and molecular-docking analysis. Collectively, these findings expand the current understanding of IMP interactions and enhance the comprehension of the interaction of IMP with plant F-actin. They also unveil a novel interaction pathway that may influence phytoplasma pathogenicity and host plant responses related to PHYL1. This discovery could pave the way for the development of new strategies to overcome phytoplasma-related plant diseases.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 384-394"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140665379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward a quantitative description of solvation structure: a framework for differential solution scattering measurements","authors":"Niklas B. Thompson ,&nbsp;Karen L. Mulfort ,&nbsp;David M. Tiede ,&nbsp;I. Robinson (Editor)","doi":"10.1107/S2052252524003282","DOIUrl":"10.1107/S2052252524003282","url":null,"abstract":"<div><p>Total X-ray scattering measurements of dilute solutions are uniquely well suited to address the structural basis for the effects of solvation, exemplified by the success of small-/wide-angle X-ray scattering studies of macromolecules in solution. Herein, we extend this methodology to the high-energy X-ray regime by developing a theoretical framework to describe the differential solution scattering experiment, supported by numerical simulation and experiment.</p></div><div><p>Appreciating that the role of the solute–solvent and other outer-sphere interactions is essential for understanding chemistry and chemical dynamics in solution, experimental approaches are needed to address the structural consequences of these interactions, complementing condensed-matter simulations and coarse-grained theories. High-energy X-ray scattering (HEXS) combined with pair distribution function analysis presents the opportunity to probe these structures directly and to develop quantitative, atomistic models of molecular systems <em>in situ</em> in the solution phase. However, at concentrations relevant to solution-phase chemistry, the total scattering signal is dominated by the bulk solvent, prompting researchers to adopt a differential approach to eliminate this unwanted background. Though similar approaches are well established in quantitative structural studies of macromolecules in solution by small- and wide-angle X-ray scattering (SAXS/WAXS), analogous studies in the HEXS regime—where sub-ångström spatial resolution is achieved—remain underdeveloped, in part due to the lack of a rigorous theoretical description of the experiment. To address this, herein we develop a framework for differential solution scattering experiments conducted at high energies, which includes concepts of the solvent-excluded volume introduced to describe SAXS/WAXS data, as well as concepts from the time-resolved X-ray scattering community. Our theory is supported by numerical simulations and experiment and paves the way for establishing quantitative methods to determine the atomic structures of small molecules in solution with resolution approaching that of crystallography.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 423-433"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11067739/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140857579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The ABC toxin complex from Yersinia entomophaga can package three different cytotoxic components expressed from distinct genetic loci in an unfolded state: the structures of both shell and cargo","authors":"Jason N. Busby ,&nbsp;Sarah Trevelyan ,&nbsp;Cassandra L. Pegg ,&nbsp;Edward D. Kerr ,&nbsp;Benjamin L. Schulz ,&nbsp;Irene Chassagnon ,&nbsp;Michael J. Landsberg ,&nbsp;Mitchell K. Weston ,&nbsp;Mark R. H. Hurst ,&nbsp;J. Shaun Lott ,&nbsp;A. Thorn (Editor)","doi":"10.1107/S2052252524001969","DOIUrl":"10.1107/S2052252524001969","url":null,"abstract":"<div><p>A cytotoxin encoded by an ‘orphan’ genetic locus in the insect pathogen <em>Yersinia entomophaga</em> is shown to be a functional part of an ABC toxin complex, and the structures of both the RHS-repeat-containing ‘shell’ and the free toxin alone are determined by X-ray crystallography. The structure of the toxin indicates that it most likely functions by directly modifying actin in the target cell.</p></div><div><p>Bacterial ABC toxin complexes (Tcs) comprise three core proteins: TcA, TcB and TcC. The TcA protein forms a pentameric assembly that attaches to the surface of target cells and penetrates the cell membrane. The TcB and TcC proteins assemble as a heterodimeric TcB–TcC subcomplex that makes a hollow shell. This TcB–TcC subcomplex self-cleaves and encapsulates within the shell a cytotoxic ‘cargo’ encoded by the C-terminal region of the TcC protein. Here, we describe the structure of a previously uncharacterized TcC protein from <em>Yersinia entomophaga</em>, encoded by a gene at a distant genomic location from the genes encoding the rest of the toxin complex, in complex with the TcB protein. When encapsulated within the TcB–TcC shell, the C-terminal toxin adopts an unfolded and disordered state, with limited areas of local order stabilized by the chaperone-like inner surface of the shell. We also determined the structure of the toxin cargo alone and show that when not encapsulated within the shell, it adopts an ADP-ribosyltransferase fold most similar to the catalytic domain of the SpvB toxin from <em>Salmonella typhimurium</em>. Our structural analysis points to a likely mechanism whereby the toxin acts directly on actin, modifying it in a way that prevents normal polymerization.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 299-308"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11067744/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140184521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linking solid-state phenomena via energy differences in ‘archetype crystal structures’","authors":"B. Dittrich ,&nbsp;L. E. Connor ,&nbsp;F. P. A. Fabbiani ,&nbsp;P. Piechon ,&nbsp;A. Fitch (Editor)","doi":"10.1107/S2052252524002641","DOIUrl":"10.1107/S2052252524002641","url":null,"abstract":"<div><p>Solid-state phenomena like disorder, polymorphism but also the occurrence of high-<em>Z</em>′ crystal structures can be linked via energy differences in ‘archetype crystal structures’, which will permit better prediction of their occurrence.</p></div><div><p>Categorization underlies understanding. Conceptualizing solid-state structures of organic molecules with ‘archetype crystal structures’ bridges established categories of disorder, polymorphism and solid solutions and is herein extended to special position and high-<em>Z</em>′ structures. The concept was developed in the context of disorder modelling [Dittrich, B. (2021). <em>IUCrJ</em>, <strong>8</strong>, 305–318] and relies on adding quantum chemical energy differences between disorder components to other criteria as an explanation as to why disorder – and disappearing disorder – occurs in an average structure. Part of the concept is that disorder, as probed by diffraction, affects entire molecules, rather than just the parts of a molecule with differing conformations, and the finding that an <em>R·T</em> energy difference between disorder archetypes is usually not exceeded. An illustrative example combining disorder and special positions is the crystal structure of oestradiol hemihydrate analysed here, where its space-group/subgroup relationship is required to explain its disorder of hydrogen-bonded hydrogen atoms. In addition, we show how high-<em>Z</em>′ structures can also be analysed energetically and understood via archetypes: high-<em>Z</em>′ structures occur when an energy gain from combining different rather than overall alike conformations in a crystal significantly exceeds <em>R·T</em>, and this finding is discussed in the context of earlier explanations in the literature. Twinning is not related to archetype structures since it involves macroscopic domains of the same crystal structure. Archetype crystal structures are distinguished from crystal structure prediction trial structures in that an experimental reference structure is required for them. Categorization into archetype structures also has practical relevance, leading to a new practice of disorder modelling in experimental least-squares refinement alluded to in the above-mentioned publication.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 347-358"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140694912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystal structure of human peptidylarginine deiminase type VI (PAD6) provides insights into its inactivity","authors":"Fanomezana M. Ranaivoson ,&nbsp;Rieke Bande ,&nbsp;Isabell Cardaun ,&nbsp;Antonio De Riso ,&nbsp;Annette Gärtner ,&nbsp;Pui Loke ,&nbsp;Christina Reinisch ,&nbsp;Prasuna Vogirala ,&nbsp;Edward Beaumont ,&nbsp;J. L. Smith (Editor)","doi":"10.1107/S2052252524002549","DOIUrl":"10.1107/S2052252524002549","url":null,"abstract":"<div><p>The human peptidylarginine deiminase type VI (PAD6) is essential in oocyte and embryonic development as a component of the supramolecular assemblies called cytoplasmic lattices. The crystal structure presented here suggests PAD6 assembles as a dimer resembling other PADs, albeit with compromised abilities to bind Ca²⁺ and substrates. This aligns with existing <em>in vitro</em> data which indicate an enzymatically inactive isoform of PAD.</p></div><div><p>Human peptidylarginine deiminase isoform VI (PAD6), which is predominantly limited to cytoplasmic lattices in the mammalian oocytes in ovarian tissue, is essential for female fertility. It belongs to the peptidylarginine deiminase (PAD) enzyme family that catalyzes the conversion of arginine residues to citrulline in proteins. In contrast to other members of the family, recombinant PAD6 was previously found to be catalytically inactive. We sought to provide structural insight into the human homologue to shed light on this observation. We report here the first crystal structure of PAD6, determined at 1.7 Å resolution. PAD6 follows the same domain organization as other structurally known PAD isoenzymes. Further structural analysis and size-exclusion chromatography show that PAD6 behaves as a homodimer similar to PAD4. Differential scanning fluorimetry suggests that PAD6 does not coordinate Ca²⁺ which agrees with acidic residues found to coordinate Ca²⁺ in other PAD homologs not being conserved in PAD6. The crystal structure of PAD6 shows similarities with the inactive state of <em>apo</em> PAD2, in which the active site conformation is unsuitable for catalytic citrullination. The putative active site of PAD6 adopts a non-productive conformation that would not allow protein–substrate binding due to steric hindrance with rigid secondary structure elements. This observation is further supported by the lack of activity on the histone H3 and cytokeratin 5 substrates. These findings suggest a different mechanism for enzymatic activation compared with other PADs; alternatively, PAD6 may exert a non-enzymatic function in the cytoplasmic lattice of oocytes and early embryos.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 395-404"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140661838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chaperone-mediated MHC-I peptide exchange in antigen presentation","authors":"Jiansheng Jiang ,&nbsp;Kannan Natarajan ,&nbsp;David H. Margulies ,&nbsp;J. L. Smith (Editor)","doi":"10.1107/S2052252524002768","DOIUrl":"10.1107/S2052252524002768","url":null,"abstract":"<div><p>This topic review summarizes structures of chaperones complexed with MHC-I, the structural principles that govern peptide exchange and the mechanism in antigen presentation.</p></div><div><p>This work focuses on molecules that are encoded by the major histocompatibility complex (MHC) and that bind self-, foreign- or tumor-derived peptides and display these at the cell surface for recognition by receptors on T lymphocytes (T cell receptors, TCR) and natural killer (NK) cells. The past few decades have accumulated a vast knowledge base of the structures of MHC molecules and the complexes of MHC/TCR with specificity for many different peptides. In recent years, the structures of MHC-I molecules complexed with chaperones that assist in peptide loading have been revealed by X-ray crystallography and cryogenic electron microscopy. These structures have been further studied using mutagenesis, molecular dynamics and NMR approaches. This review summarizes the current structures and dynamic principles that govern peptide exchange as these relate to the process of antigen presentation.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 287-298"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140662862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-series analysis of rhenium(I) organometallic covalent binding to a model protein for drug development","authors":"Francois J.F. Jacobs ,&nbsp;John R. Helliwell ,&nbsp;Alice Brink ,&nbsp;E. N. Baker (Editor)","doi":"10.1107/S2052252524002598","DOIUrl":"10.1107/S2052252524002598","url":null,"abstract":"<div><p>A detailed analysis of rhenium(I) organometallic covalent binding to a model protein is conducted at seven time points over 38 weeks. Changes in the protein structure induced at the Re binding sites over the time series as well as the relationship between the proximity of the solvent channels to the residues containing the highest-occupied Re are described.</p></div><div><p>Metal-based complexes with their unique chemical properties, including multiple oxidation states, radio-nuclear capabilities and various coordination geometries yield value as potential pharmaceuticals. Understanding the interactions between metals and biological systems will prove key for site-specific coordination of new metal-based lead compounds. This study merges the concepts of target coordination with fragment-based drug methodologies, supported by varying the anomalous scattering of rhenium along with infrared spectroscopy, and has identified rhenium metal sites bound covalently with two amino acid types within the model protein. A time-based series of lysozyme-rhenium-imidazole (HEWL-Re-Imi) crystals was analysed systematically over a span of 38 weeks. The main rhenium covalent coordination is observed at His15, Asp101 and Asp119. Weak (<em>i.e.</em> noncovalent) interactions are observed at other aspartic, asparagine, proline, tyrosine and tryptophan side chains. Detailed bond distance comparisons, including precision estimates, are reported, utilizing the diffraction precision index supplemented with small-molecule data from the Cambridge Structural Database. Key findings include changes in the protein structure induced at the rhenium metal binding site, not observed in similar metal-free structures. The binding sites are typically found along the solvent-channel-accessible protein surface. The three primary covalent metal binding sites are consistent throughout the time series, whereas binding to neighbouring amino acid residues changes through the time series. Co-crystallization was used, consistently yielding crystals four days after setup. After crystal formation, soaking of the compound into the crystal over 38 weeks is continued and explains these structural adjustments. It is the covalent bond stability at the three sites, their proximity to the solvent channel and the movement of residues to accommodate the metal that are important, and may prove useful for future radiopharmaceutical development including target modification.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 359-373"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140683057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D electron diffraction goes multipolar","authors":"R. Beanland","doi":"10.1107/S2052252524003774","DOIUrl":"10.1107/S2052252524003774","url":null,"abstract":"<div><p>Over 30 years ago, it was shown that bonding between atoms has a noticeable effect on convergent beam electron diffraction patterns. The paper by Olech <em>et al.</em> [(2024). <em>IUCrJ</em>, <strong>11</strong>, 309–324] demonstrates that its influence is also clearly present in 3D electron diffraction data, opening up new possibilities for quantum crystallography.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 277-278"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11067748/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140851808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A solid solution to computational challenges presented by crystal structures exhibiting disorder","authors":"Peter R. Spackman","doi":"10.1107/S2052252524001684","DOIUrl":"10.1107/S2052252524001684","url":null,"abstract":"<div><p>Crystal structues exhibiting disorder still present a barrier for many computational methods. Dittrich <em>et al.</em> [(2024). <em>IUCrJ</em>, <strong>11</strong>, 347–358] showcase a unified approach, tackling solid solutions, near symmetry and more.</p></div>","PeriodicalId":14775,"journal":{"name":"IUCrJ","volume":"11 3","pages":"Pages 275-276"},"PeriodicalIF":3.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11067745/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140860142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}