Browsing by Author "Miller, Mitchell D."
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Item A collagen glucosyltransferase drives lung adenocarcinoma progression in mice(Springer Nature, 2021) Guo, Hou-Fu; Bota-Rabassedas, Neus; Terajima, Masahiko; Leticia Rodriguez, B.; Gibbons, Don L.; Chen, Yulong; Banerjee, Priyam; Tsai, Chi-Lin; Tan, Xiaochao; Liu, Xin; Yu, Jiang; Tokmina-Roszyk, Michal; Stawikowska, Roma; Fields, Gregg B.; Miller, Mitchell D.; Wang, Xiaoyan; Lee, Juhoon; Dalby, Kevin N.; Creighton, Chad J.; Phillips, George N.Jr.; Tainer, John A.; Yamauchi, Mitsuo; Kurie, Jonathan M.Cancer cells are a major source of enzymes that modify collagen to create a stiff, fibrotic tumor stroma. High collagen lysyl hydroxylase 2 (LH2) expression promotes metastasis and is correlated with shorter survival in lung adenocarcinoma (LUAD) and other tumor types. LH2 hydroxylates lysine (Lys) residues on fibrillar collagen’s amino- and carboxy-terminal telopeptides to create stable collagen cross-links. Here, we show that electrostatic interactions between the LH domain active site and collagen determine the unique telopeptidyl lysyl hydroxylase (tLH) activity of LH2. However, CRISPR/Cas-9-mediated inactivation of tLH activity does not fully recapitulate the inhibitory effect of LH2 knock out on LUAD growth and metastasis in mice, suggesting that LH2 drives LUAD progression, in part, through a tLH-independent mechanism. Protein homology modeling and biochemical studies identify an LH2 isoform (LH2b) that has previously undetected collagen galactosylhydroxylysyl glucosyltransferase (GGT) activity determined by a loop that enhances UDP-glucose-binding in the GLT active site and is encoded by alternatively spliced exon 13 A. CRISPR/Cas-9-mediated deletion of exon 13 A sharply reduces the growth and metastasis of LH2b-expressing LUADs in mice. These findings identify a previously unrecognized collagen GGT activity that drives LUAD progression.Item CrysFormer: Protein structure determination via Patterson maps, deep learning, and partial structure attention(AIP Publishing LLC, 2024) Pan, Tom; Dun, Chen; Jin, Shikai; Miller, Mitchell D.; Kyrillidis, Anastasios; Phillips, George N., Jr.Determining the atomic-level structure of a protein has been a decades-long challenge. However, recent advances in transformers and related neural network architectures have enabled researchers to significantly improve solutions to this problem. These methods use large datasets of sequence information and corresponding known protein template structures, if available. Yet, such methods only focus on sequence information. Other available prior knowledge could also be utilized, such as constructs derived from x-ray crystallography experiments and the known structures of the most common conformations of amino acid residues, which we refer to as partial structures. To the best of our knowledge, we propose the first transformer-based model that directly utilizes experimental protein crystallographic data and partial structure information to calculate electron density maps of proteins. In particular, we use Patterson maps, which can be directly obtained from x-ray crystallography experimental data, thus bypassing the well-known crystallographic phase problem. We demonstrate that our method, CrysFormer, achieves precise predictions on two synthetic datasets of peptide fragments in crystalline forms, one with two residues per unit cell and the other with fifteen. These predictions can then be used to generate accurate atomic models using established crystallographic refinement programs.Item Crystal Structure of Human Protein N-Terminal Glutamine Amidohydrolase, an Initial Component of the N-End Rule Pathway(Public Library of Science, 2014) Park, Mi Seul; Bitto, Eduard; Kim, Kyung Rok; Bingman, Craig A.; Miller, Mitchell D.; Kim, Hyun-Jung; Han, Byung Woo; Phillips, George N.Jr.The N-end rule states that half-life of protein is determined by their N-terminal amino acid residue. N-terminal glutamine amidohydrolase (Ntaq) converts N-terminal glutamine to glutamate by eliminating the amine group and plays an essential role in the N-end rule pathway for protein degradation. Here, we report the crystal structure of human Ntaq1 bound with the N-terminus of a symmetry-related Ntaq1 molecule at 1.5 Å resolution. The structure reveals a monomeric globular protein with alpha-beta-alpha three-layer sandwich architecture. The catalytic triad located in the active site, Cys-His-Asp, is highly conserved among Ntaq family and transglutaminases from diverse organisms. The N-terminus of a symmetry-related Ntaq1 molecule bound in the substrate binding cleft and the active site suggest possible substrate binding mode of hNtaq1. Based on our crystal structure of hNtaq1 and docking study with all the tripeptides with N-terminal glutamine, we propose how the peptide backbone recognition patch of hNtaq1 forms nonspecific interactions with N-terminal peptides of substrate proteins. Upon binding of a substrate with N-terminal glutamine, active site catalytic triad mediates the deamination of the N-terminal residue to glutamate by a mechanism analogous to that of cysteine proteases.Item Drop-on-demand sample delivery for studying biocatalysts in action at X-ray free-electron lasers(Nature Publishing Group, 2017) Fuller, Franklin D.; Gul, Sheraz; Chatterjee, Ruchira; Burgie, E.Sethe; Young, Iris D.; Lebrette, Hugo; Srinivas, Vivek; Brewster, Aaron S.; Michels-Clark, Tara; Clinger, Jonathan A.; Andi, Babak; Ibrahim, Mohamed; Pastor, Ernest; de Lichtenberg, Casper; Hussein, Rana; Pollock, Christopher J.; Zhang, Miao; Stan, Claudiu A.; Kroll, Thomas; Fransson, Thomas; Weninger, Clemens; Kubin, Markus; Aller, Pierre; Lassalle, Louise; Bräuer, Philipp; Miller, Mitchell D.; Amin, Muhamed; Koroidov, Sergey; Roessler, Christian G.; Allaire, Marc; Sierra, Raymond G.; Docker, Peter T.; Glownia, James M.; Nelson, Silke; Koglin, Jason E.; Zhu, Diling; Chollet, Matthieu; Song, Sanghoon; Lemke, Henrik; Liang, Mengning; Sokaras, Dimosthenis; Alonso-Mori, Roberto; Zouni, Athina; Messinger, Johannes; Bergmann, Uwe; Boal, Amie K.; Bollinger, J.Martin Jr.; Krebs, Carsten; Högbom, Martin; Phillips, George N.Jr.; Vierstra,, Richard D.; Sauter, Nicholas K.; Orville, Allen M.; Kern, Jan; Yachandra, Vittal K.; Yano, JunkoX-ray crystallography at X-ray free-electron laser sources is a powerful method for studying macromolecules at biologically relevant temperatures. Moreover, when combined with complementary techniques like X-ray emission spectroscopy, both global structures and chemical properties of metalloenzymes can be obtained concurrently, providing insights into the interplay between the protein structure and dynamics and the chemistry at an active site. The implementation of such a multimodal approach can be compromised by conflicting requirements to optimize each individual method. In particular, the method used for sample delivery greatly affects the data quality. We present here a robust way of delivering controlled sample amounts on demand using acoustic droplet ejection coupled with a conveyor belt drive that is optimized for crystallography and spectroscopy measurements of photochemical and chemical reactions over a wide range of time scales. Studies with photosystem II, the phytochrome photoreceptor, and ribonucleotide reductase R2 illustrate the power and versatility of this method.Item Enzyme intermediates captured “on the fly” by mix-and-inject serial crystallography(Springer Nature, 2018) Olmos, Jose Luis Jr.; Pandey, Suraj; Martin-Garcia, Jose M.; Calvey, George; Katz, Andrea; Knoska, Juraj; Kupitz, Christopher; Hunter, Mark S.; Liang, Mengning; Oberthuer, Dominik; Yefanov, Oleksandr; Wiedorn, Max; Heyman, Michael; Holl, Mark; Pande, Kanupriya; Barty, Anton; Miller, Mitchell D.; Stern, Stephan; Roy-Chowdhury, Shatabdi; Coe, Jesse; Nagaratnam, Nirupa; Zook, James; Verburgt, Jacob; Norwood, Tyler; Poudyal, Ishwor; Xu, David; Koglin, Jason E.; Seaberg, Matthew H.; Zhao, Yun; Bajt, Saša; Grant, Thomas; Mariani, Valerio; Nelson, Garrett; Subramanian, Ganesh; Bae, Euiyoung; Fromme, Raimund; Fung, Russell; Schwander, Peter; Frank, Matthias; White, Thomas A.; Weierstall, Uwe; Zatsepin, Nadia; Spence, John; Fromme, Petra; Chapman, Henry N.; Pollack, Lois; Tremblay, Lee; Ourmazd, Abbas; Phillips, George N.Jr.; Schmidt, MariusBACKGROUND: Ever since the first atomic structure of an enzyme was solved, the discovery of the mechanism and dynamics of reactions catalyzed by biomolecules has been the key goal for the understanding of the molecular processes that drive life on earth. Despite a large number of successful methods for trapping reaction intermediates, the direct observation of an ongoing reaction has been possible only in rare and exceptional cases. RESULTS: Here, we demonstrate a general method for capturing enzyme catalysis "in action" by mix-and-inject serial crystallography (MISC). Specifically, we follow the catalytic reaction of the Mycobacterium tuberculosis β-lactamase with the third-generation antibiotic ceftriaxone by time-resolved serial femtosecond crystallography. The results reveal, in near atomic detail, antibiotic cleavage and inactivation from 30 ms to 2 s. CONCLUSIONS: MISC is a versatile and generally applicable method to investigate reactions of biological macromolecules, some of which are of immense biological significance and might be, in addition, important targets for structure-based drug design. With megahertz X-ray pulse rates expected at the Linac Coherent Light Source II and the European X-ray free-electron laser, multiple, finely spaced time delays can be collected rapidly, allowing a comprehensive description of biomolecular reactions in terms of structure and kinetics from the same set of X-ray data.Item Improving the efficiency of molecular replacement by utilizing a new iterative transform phasing algorithm(International Union of Crystallography, 2016) He, Hongxing; Fang, Hengrui; Miller, Mitchell D.; Phillips, George N.Jr.; Su, Wu-PeiAn iterative transform method proposed previously for direct phasing of high-solvent-content protein crystals is employed for enhancing the molecular-replacement (MR) algorithm in protein crystallography. Target structures that are resistant to conventional MR due to insufficient similarity between the template and target structures might be tractable with this modified phasing method. Trial calculations involving three different structures are described to test and illustrate the methodology. The relationship of the approach toᅠPHENIX Phaser-MRᅠandᅠMR-Rosettaᅠis discussed.Item Moving beyond static snapshots: Protein dynamics and the Protein Data Bank(Elsevier Inc on behalf of American Society for Biochemistry and Molecular Biology, 2021) Miller, Mitchell D.; Phillips, George N.Jr.Proteins are the molecular machines of living systems. Their dynamics are an intrinsic part of their evolutionary selection in carrying out their biological functions. Although the dynamics are more difficult to observe than a static, average structure, we are beginning to observe these dynamics and form sound mechanistic connections between structure, dynamics, and function. This progress is highlighted in case studies from myoglobin and adenylate kinase to the ribosome and molecular motors where these molecules are being probed with a multitude of techniques across many timescales. New approaches to time-resolved crystallography are allowing simple “movies” to be taken of proteins in action, and new methods of mapping the variations in cryo-electron microscopy are emerging to reveal a more complete description of life’s machines. The results of these new methods are aided in their dissemination by continual improvements in curation and distribution by the Protein Data Bank and their partners around the world.Item Pro-metastatic collagen lysyl hydroxylase dimer assemblies stabilized by Fe2+-binding(Springer Nature, 2018) Guo, Hou-Fu; Tsai, Chi-Lin; Terajima, Masahiko; Tan, Xiaochao; Banerjee, Priyam; Miller, Mitchell D.; Liu, Xin; Yu, Jiang; Byemerwa, Jovita; Alvarado, Sarah K.; Kaoud, Tamer S.; Dalby, Kevin N.; Bota-Rabassedas, Neus; Chen, Yulong; Yamauchi, Mitsuo; Tainer, John A.; Phillips, George N.Jr.; Kurie, Jonathan M.Collagen lysyl hydroxylases (LH1-3) are Fe2+- and 2-oxoglutarate (2-OG)-dependent oxygenases that maintain extracellular matrix homeostasis. High LH2 levels cause stable collagen cross-link accumulations that promote fibrosis and cancer progression. However, developing LH antagonists will require structural insights. Here, we report a 2 Å crystal structure and X-ray scattering on dimer assemblies for the LH domain of L230 in Acanthamoeba polyphaga mimivirus. Loop residues in the double-stranded β-helix core generate a tail-to-tail dimer. A stabilizing hydrophobic leucine locks into an aromatic tyrosine-pocket on the opposite subunit. An active site triad coordinates Fe2+. The two active sites flank a deep surface cleft that suggest dimerization creates a collagen-binding site. Loss of Fe2+-binding disrupts the dimer. Dimer disruption and charge reversal in the cleft increase Km and reduce LH activity. Ectopic L230 expression in tumors promotes collagen cross-linking and metastasis. These insights suggest inhibitor targets for fibrosis and cancer.Item Protein target highlights in CASP15: Analysis of models by structure providers(Wiley, 2023) Alexander, Leila T.; Durairaj, Janani; Kryshtafovych, Andriy; Abriata, Luciano A.; Bayo, Yusupha; Bhabha, Gira; Breyton, Cécile; Caulton, Simon G.; Chen, James; Degroux, Séraphine; Ekiert, Damian C.; Erlandsen, Benedikte S.; Freddolino, Peter L.; Gilzer, Dominic; Greening, Chris; Grimes, Jonathan M.; Grinter, Rhys; Gurusaran, Manickam; Hartmann, Marcus D.; Hitchman, Charlie J.; Keown, Jeremy R.; Kropp, Ashleigh; Kursula, Petri; Lovering, Andrew L.; Lemaitre, Bruno; Lia, Andrea; Liu, Shiheng; Logotheti, Maria; Lu, Shuze; Markússon, Sigurbjörn; Miller, Mitchell D.; Minasov, George; Niemann, Hartmut H.; Opazo, Felipe; Phillips Jr, George N.; Davies, Owen R.; Rommelaere, Samuel; Rosas-Lemus, Monica; Roversi, Pietro; Satchell, Karla; Smith, Nathan; Wilson, Mark A.; Wu, Kuan-Lin; Xia, Xian; Xiao, Han; Zhang, Wenhua; Zhou, Z. Hong; Fidelis, Krzysztof; Topf, Maya; Moult, John; Schwede, TorstenWe present an in-depth analysis of selected CASP15 targets, focusing on their biological and functional significance. The authors of the structures identify and discuss key protein features and evaluate how effectively these aspects were captured in the submitted predictions. While the overall ability to predict three-dimensional protein structures continues to impress, reproducing uncommon features not previously observed in experimental structures is still a challenge. Furthermore, instances with conformational flexibility and large multimeric complexes highlight the need for novel scoring strategies to better emphasize biologically relevant structural regions. Looking ahead, closer integration of computational and experimental techniques will play a key role in determining the next challenges to be unraveled in the field of structural molecular biology.Item Reader domain specificity and lysine demethylase-4 family function(Springer Nature, 2016) Su, Zhangli; Wang, Fengbin; Lee, Jin-Hee; Stephens, Kimberly E.; Papazyan, Romeo; Voronina, Ekaterina; Krautkramer, Kimberly A.; Raman, Ana; Thorpe, Jeremy J.; Boersma, Melissa D.; Kuznetsov, Vyacheslav I.; Miller, Mitchell D.; Taverna, Sean D.; Phillips, George N.Jr.; Denu, John M.The KDM4 histone demethylases are conserved epigenetic regulators linked to development, spermatogenesis and tumorigenesis. However, how the KDM4 family targets specific chromatin regions is largely unknown. Here, an extensive histone peptide microarray analysis uncovers trimethyl-lysine histone-binding preferences among the closely related KDM4 double tudor domains (DTDs). KDM4A/B DTDs bind strongly to H3K23me3, a poorly understood histone modification recently shown to be enriched in meiotic chromatin of ciliates and nematodes. The 2.28 Å co-crystal structure of KDM4A-DTD in complex with H3K23me3 peptide reveals key intermolecular interactions for H3K23me3 recognition. Furthermore, analysis of the 2.56 Å KDM4B-DTD crystal structure pinpoints the underlying residues required for exclusive H3K23me3 specificity, an interaction supported by in vivo co-localization of KDM4B and H3K23me3 at heterochromatin in mammalian meiotic and newly postmeiotic spermatocytes. In vitrodemethylation assays suggest H3K23me3 binding by KDM4B stimulates H3K36 demethylation. Together, these results provide a possible mechanism whereby H3K23me3-binding by KDM4B directs localized H3K36 demethylation during meiosis and spermatogenesis.Item Structural Basis for the Stereochemical Control of Amine Installation in Nucleotide Sugar Aminotransferases(American Chemical Society, 2015) Wang, Fengbin; Singh, Shanteri; Xu, Weijun; Helmich, Kate E.; Miller, Mitchell D.; Cao, Hongnan; Bingman, Craig A.; Thorson, Jon S.; Phillips, George N.Jr.Sugar aminotransferases (SATs) are an important class of tailoring enzymes that catalyze the 5'-pyridoxal phosphate (PLP)-dependent stereo- and regiospecific installation of an amino group from an amino acid donor (typically L-Glu or L-Gln) to a corresponding ketosugar nucleotide acceptor. Herein we report the strategic structural study of two homologous C4 SATs (Micromonospora echinospora CalS13 and Escherichia coli WecE) that utilize identical substrates but differ in their stereochemistry of aminotransfer. This study reveals for the first time a new mode of SAT sugar nucleotide binding and, in conjunction with previously reported SAT structural studies, provides the basis from which to propose a universal model for SAT stereo- and regiochemical control of amine installation. Specifically, the universal model put forth highlights catalytic divergence to derive solely from distinctions within nucleotide sugar orientation upon binding within a relatively fixed SAT active site where the available ligand bound structures of the three out of four representative C3 and C4 SAT examples provide a basis for the overall model. Importantly, this study presents a new predictive model to support SAT functional annotation, biochemical study and rational engineering.Item Structure-Guided Functional Characterization of Enediyne Self-Sacrifice Resistance Proteins, CalU16 and CalU19(American Chemical Society, 2014) Elshahawi, Sherif I.; Ramelot, Theresa A.; Seetharaman, Jayaraman; Chen, Jing Han; Singh, Shanteri; Yang, Yunhuang; Pederson, Kari; Kharel, Madan K.; Xiao, Rong; Lew, Scott; Yennamalli, Ragothaman M.; Miller, Mitchell D.; Wang, Fengbin; Tong, Liang; Montelione, Gaetano T.; Kennedy, Michael A.; Bingman, Craig A.; Zhu, Haining; Phillips, George N.Jr.; Thorson, Jon S.Calicheamicin γ1I (1) is an enediyne antitumor compound produced by Micromonospora echinospora spp. calichensis, and its biosynthetic gene cluster has been previously reported. Despite extensive analysis and biochemical study, several genes in the biosynthetic gene cluster of 1 remain functionally unassigned. Using a structural genomics approach and biochemical characterization, two proteins encoded by genes from the 1 biosynthetic gene cluster assigned as “unknowns”, CalU16 and CalU19, were characterized. Structure analysis revealed that they possess the STeroidogenic Acute Regulatory protein related lipid Transfer (START) domain known mainly to bind and transport lipids and previously identified as the structural signature of the enediyne self-resistance protein CalC. Subsequent study revealed calU16 and calU19 to confer resistance to 1, and reminiscent of the prototype CalC, both CalU16 and CalU19 were cleaved by 1 in vitro. Through site-directed mutagenesis and mass spectrometry, we identified the site of cleavage in each protein and characterized their function in conferring resistance against 1. This report emphasizes the importance of structural genomics as a powerful tool for the functional annotation of unknown proteins.Item The Structure of the Arabidopsis PEX4-PEX22 Peroxin Complex—Insights Into Ubiquitination at the Peroxisomal Membrane(Frontiers Media S.A., 2022) Traver, Melissa S.; Bradford, Sarah E.; Olmos, Jose Luis; Wright, Zachary J.; Miller, Mitchell D.; Xu, Weijun; Phillips, George N.; Bartel, BonniePeroxisomes are eukaryotic organelles that sequester critical oxidative reactions and process the resulting reactive oxygen species into less toxic byproducts. Peroxisome function and formation are coordinated by peroxins (PEX proteins) that guide peroxisome biogenesis and division and shuttle proteins into the lumen and membrane of the organelle. Despite the importance of peroxins in plant metabolism and development, no plant peroxin structures have been reported. Here we report the X-ray crystal structure of the PEX4-PEX22 peroxin complex from the reference plant Arabidopsis thaliana. PEX4 is a ubiquitin-conjugating enzyme (UBC) that ubiquitinates proteins associated with the peroxisomal membrane, and PEX22 is a peroxisomal membrane protein that anchors PEX4 to the peroxisome and facilitates PEX4 activity. We co-expressed Arabidopsis PEX4 as a translational fusion with the soluble PEX4-interacting domain of PEX22 in E. coli. The fusion was linked via a protease recognition site, allowing us to separate PEX4 and PEX22 following purification and solve the structure of the complex. We compared the structure of the PEX4-PEX22 complex to the previously published structures of yeast orthologs. Arabidopsis PEX4 displays the typical UBC structure expected from its sequence. Although Arabidopsis PEX22 lacks notable sequence identity to yeast PEX22, it maintains a similar Rossmann fold-like structure. Several salt bridges are positioned to contribute to the specificity of PEX22 for PEX4 versus other Arabidopsis UBCs, and the long unstructured PEX22 tether would allow PEX4-mediated ubiquitination of distant peroxisomal membrane targets without dissociation from PEX22. The Arabidopsis PEX4-PEX22 structure also revealed that the residue altered in pex4-1 (P123L), a mutant previously isolated via a forward-genetic screen for peroxisomal dysfunction, is near the active site cysteine of PEX4. We demonstrated in vitro UBC activity for the PEX4-PEX22 complex and found that the pex4-1 enzyme has reduced in vitro ubiquitin-conjugating activity and altered specificity compared to PEX4. Our findings illuminate the role of PEX4 and PEX22 in peroxisome structure and function and provide tools for future exploration of ubiquitination at the peroxisome surface.