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Aiyer S, Baldwin PR, Tan SM, Shan Z, Oh J, Mehrani A, Bowman ME, Louie G, Passos DO, Đorđević-Marquardt S, Mietzsch M, Hull JA, Hoshika S, Barad BA, Grotjahn DA, McKenna R, Agbandje-McKenna M, Benner SA, Noel JAP, Wang D, Tan YZ, Lyumkis D. Overcoming resolution attenuation during tilted cryo-EM data collection. Nat Commun 2024; 15:389. [PMID: 38195598 PMCID: PMC10776679 DOI: 10.1038/s41467-023-44555-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 12/15/2023] [Indexed: 01/11/2024] Open
Abstract
Structural biology efforts using cryogenic electron microscopy are frequently stifled by specimens adopting "preferred orientations" on grids, leading to anisotropic map resolution and impeding structure determination. Tilting the specimen stage during data collection is a generalizable solution but has historically led to substantial resolution attenuation. Here, we develop updated data collection and image processing workflows and demonstrate, using multiple specimens, that resolution attenuation is negligible or significantly reduced across tilt angles. Reconstructions with and without the stage tilted as high as 60° are virtually indistinguishable. These strategies allowed the reconstruction to 3 Å resolution of a bacterial RNA polymerase with preferred orientation, containing an unnatural nucleotide for studying novel base pair recognition. Furthermore, we present a quantitative framework that allows cryo-EM practitioners to define an optimal tilt angle during data acquisition. These results reinforce the utility of employing stage tilt for data collection and provide quantitative metrics to obtain isotropic maps.
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Affiliation(s)
- Sriram Aiyer
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Philip R Baldwin
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Shi Min Tan
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558, Singapore
| | - Zelin Shan
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Juntaek Oh
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
- College of Pharmacy, Kyung Hee University, Seoul, 02247, Republic of Korea
| | - Atousa Mehrani
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Marianne E Bowman
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Gordon Louie
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Dario Oliveira Passos
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | | | - Mario Mietzsch
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Joshua A Hull
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Shuichi Hoshika
- Foundation for Applied Molecular Evolution, 13709 Progress Blvd Box 7, Alachua, FL, 32615, USA
| | - Benjamin A Barad
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Danielle A Grotjahn
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Steven A Benner
- Foundation for Applied Molecular Evolution, 13709 Progress Blvd Box 7, Alachua, FL, 32615, USA
| | - Joseph A P Noel
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, 92093, USA
| | - Dong Wang
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, 92093, USA
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Yong Zi Tan
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558, Singapore.
- Disease Intervention Technology Laboratory (DITL), Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, Singapore, 138648, Singapore.
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore, 138673, Republic of Singapore.
| | - Dmitry Lyumkis
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA.
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA.
- Graduate School of Biological Sciences, Section of Molecular Biology, University of California San Diego, La Jolla, CA, 92093, USA.
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2
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Aiyer S, Baldwin PR, Tan SM, Shan Z, Oh J, Mehrani A, Bowman ME, Louie G, Passos DO, Đorđević-Marquardt S, Mietzsch M, Hull JA, Hoshika S, Barad BA, Grotjahn DA, McKenna R, Agbandje-McKenna M, Benner SA, Noel JAP, Wang D, Tan YZ, Lyumkis D. Overcoming Resolution Attenuation During Tilted Cryo-EM Data Collection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.14.548955. [PMID: 37503021 PMCID: PMC10369999 DOI: 10.1101/2023.07.14.548955] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Structural biology efforts using cryogenic electron microscopy are frequently stifled by specimens adopting "preferred orientations" on grids, leading to anisotropic map resolution and impeding structure determination. Tilting the specimen stage during data collection is a generalizable solution but has historically led to substantial resolution attenuation. Here, we develop updated data collection and image processing workflows and demonstrate, using multiple specimens, that resolution attenuation is negligible or significantly reduced across tilt angles. Reconstructions with and without the stage tilted as high as 60° are virtually indistinguishable. These strategies allowed the reconstruction to 3 Å resolution of a bacterial RNA polymerase with preferred orientation. Furthermore, we present a quantitative framework that allows cryo-EM practitioners to define an optimal tilt angle for dataset acquisition. These data reinforce the utility of employing stage tilt for data collection and provide quantitative metrics to obtain isotropic maps.
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3
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Gorman J, Wang C, Mason RD, Nazzari AF, Welles HC, Zhou T, Bess JW, Bylund T, Lee M, Tsybovsky Y, Verardi R, Wang S, Yang Y, Zhang B, Rawi R, Keele BF, Lifson JD, Liu J, Roederer M, Kwong PD. Cryo-EM structures of prefusion SIV envelope trimer. Nat Struct Mol Biol 2022; 29:1080-1091. [PMID: 36344847 PMCID: PMC10606957 DOI: 10.1038/s41594-022-00852-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 09/25/2022] [Indexed: 11/09/2022]
Abstract
Simian immunodeficiency viruses (SIVs) are lentiviruses that naturally infect non-human primates of African origin and seeded cross-species transmissions of HIV-1 and HIV-2. Here we report prefusion stabilization and cryo-EM structures of soluble envelope (Env) trimers from rhesus macaque SIV (SIVmac) in complex with neutralizing antibodies. These structures provide residue-level definition for SIV-specific disulfide-bonded variable loops (V1 and V2), which we used to delineate variable-loop coverage of the Env trimer. The defined variable loops enabled us to investigate assembled Env-glycan shields throughout SIV, which we found to comprise both N- and O-linked glycans, the latter emanating from V1 inserts, which bound the O-link-specific lectin jacalin. We also investigated in situ SIVmac-Env trimers on virions, determining cryo-electron tomography structures at subnanometer resolutions for an antibody-bound complex and a ligand-free state. Collectively, these structures define the prefusion-closed structure of the SIV-Env trimer and delineate variable-loop and glycan-shielding mechanisms of immune evasion conserved throughout SIV evolution.
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Affiliation(s)
- Jason Gorman
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Chunyan Wang
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Rosemarie D Mason
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | | | - Hugh C Welles
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Tongqing Zhou
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Julian W Bess
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Tatsiana Bylund
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Myungjin Lee
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Yaroslav Tsybovsky
- Electron Microscopy Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Raffaello Verardi
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Shuishu Wang
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Yongping Yang
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Baoshan Zhang
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Reda Rawi
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Brandon F Keele
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Jun Liu
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT, USA.
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
| | - Mario Roederer
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA.
| | - Peter D Kwong
- Vaccine Research Center, National Institutes of Health, Bethesda, MD, USA.
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Scaramuzza S, Castaño-Díez D. Step-by-step guide to efficient subtomogram averaging of virus-like particles with Dynamo. PLoS Biol 2021; 19:e3001318. [PMID: 34437529 PMCID: PMC8389376 DOI: 10.1371/journal.pbio.3001318] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/09/2021] [Indexed: 11/19/2022] Open
Abstract
Subtomogram averaging (STA) is a powerful image processing technique in electron tomography used to determine the 3D structure of macromolecular complexes in their native environments. It is a fast growing technique with increasing importance in structural biology. The computational aspect of STA is very complex and depends on a large number of variables. We noticed a lack of detailed guides for STA processing. Also, current publications in this field often lack a documentation that is practical enough to reproduce the results with reasonable effort, which is necessary for the scientific community to grow. We therefore provide a complete, detailed, and fully reproducible processing protocol that covers all aspects of particle picking and particle alignment in STA. The command line-based workflow is fully based on the popular Dynamo software for STA. Within this workflow, we also demonstrate how large parts of the processing pipeline can be streamlined and automatized for increased throughput. This protocol is aimed at users on all levels. It can be used for training purposes, or it can serve as basis to design user-specific projects by taking advantage of the flexibility of Dynamo by modifying and expanding the given pipeline. The protocol is successfully validated using the Electron Microscopy Public Image Archive (EMPIAR) database entry 10164 from immature HIV-1 virus-like particles (VLPs) that describe a geometry often seen in electron tomography.
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5
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Hu M, Zhang Q, Yang J, Li X. Unit quaternion description of spatial rotations in 3D electron cryo-microscopy. J Struct Biol 2020; 212:107601. [PMID: 33068699 DOI: 10.1016/j.jsb.2020.107601] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 07/14/2020] [Accepted: 08/10/2020] [Indexed: 10/23/2022]
Abstract
Electron cryo-microscopy (cryoEM) involves the estimation of spatial rotations, or saying orientations, of projection images or three-dimensional (3D) volumes. Euler angle system is widely used to describe spatial rotations in most cryoEM algorithms and software. In this review, we introduce unit quaternion as an alternate to Euler angles for describing spatial rotations, customize and develop corresponding tools for increasing demands of statistical analysis of spatial rotations in cryoEM. Some basic properties and definitions of quaternion are first recalled. Thereafter, distance and geodesic between rotations are introduced to aid comparisons and interpolations between rotations, which are prerequisites of statistics of rotations in 3D cryoEM. Furthermore, statistics of rotations are reviewed. Techniques potentially useful in cryoEM, such as calculations of the average rotation, generation of quasi-regular grids, sampling, inference with uniform distribution and angular central Gaussian (ACG) distribution, and estimation of rotation precision, are reviewed and developed. Finally, molecular symmetry presented in unit quaternion form is discussed. Unit quaternion system is shown as a convenient and comprehensive mathematical tool for cryoEM.
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Affiliation(s)
- Mingxu Hu
- Key Laboratory of Protein Sciences (Tsinghua University), Ministry of Education, Beijing, China; School of Life Science, Tsinghua University, Beijing, China; Beijing Advanced Innovation Center for Structural Biology, China
| | - Qi Zhang
- Department of Mathematical Sciences, Tsinghua University, China
| | - Jing Yang
- Department of Mathematical Sciences, Tsinghua University, China.
| | - Xueming Li
- Key Laboratory of Protein Sciences (Tsinghua University), Ministry of Education, Beijing, China; School of Life Science, Tsinghua University, Beijing, China; Beijing Advanced Innovation Center for Structural Biology, China; Beijing Frontier Research Center for Biological Structure, China.
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6
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Abstract
Cryo-electron tomography (cryo-ET) allows three-dimensional (3D) visualization of frozen-hydrated biological samples, such as protein complexes and cell organelles, in near-native environments at nanometer scale. Protein complexes that are present in multiple copies in a set of tomograms can be extracted, mutually aligned, and averaged to yield a signal-enhanced 3D structure up to sub-nanometer or even near-atomic resolution. This technique, called subtomogram averaging (StA), is powered by improvements in EM hardware and image processing software. Importantly, StA provides unique biological insights into the structure and function of cellular machinery in close-to-native contexts. In this chapter, we describe the principles and key steps of StA. We briefly cover sample preparation and data collection with an emphasis on image processing procedures related to tomographic reconstruction, subtomogram alignment, averaging, and classification. We conclude by summarizing current limitations and future directions of this technique with a focus on high-resolution StA.
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7
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Galaz-Montoya JG, Ludtke SJ. The advent of structural biology in situ by single particle cryo-electron tomography. BIOPHYSICS REPORTS 2017; 3:17-35. [PMID: 28781998 PMCID: PMC5516000 DOI: 10.1007/s41048-017-0040-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 03/30/2017] [Indexed: 01/06/2023] Open
Abstract
Single particle tomography (SPT), also known as subtomogram averaging, is a powerful technique uniquely poised to address questions in structural biology that are not amenable to more traditional approaches like X-ray crystallography, nuclear magnetic resonance, and conventional cryoEM single particle analysis. Owing to its potential for in situ structural biology at subnanometer resolution, SPT has been gaining enormous momentum in the last five years and is becoming a prominent, widely used technique. This method can be applied to unambiguously determine the structures of macromolecular complexes that exhibit compositional and conformational heterogeneity, both in vitro and in situ. Here we review the development of SPT, highlighting its applications and identifying areas of ongoing development.
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Affiliation(s)
- Jesús G Galaz-Montoya
- National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030 USA
| | - Steven J Ludtke
- National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030 USA
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8
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Frazier Z, Xu M, Alber F. TomoMiner and TomoMinerCloud: A Software Platform for Large-Scale Subtomogram Structural Analysis. Structure 2017; 25:951-961.e2. [PMID: 28552576 DOI: 10.1016/j.str.2017.04.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 12/17/2016] [Accepted: 04/28/2017] [Indexed: 11/19/2022]
Abstract
Cryo-electron tomography (cryo-ET) captures the 3D electron density distribution of macromolecular complexes in close to native state. With the rapid advance of cryo-ET acquisition technologies, it is possible to generate large numbers (>100,000) of subtomograms, each containing a macromolecular complex. Often, these subtomograms represent a heterogeneous sample due to variations in the structure and composition of a complex in situ form or because particles are a mixture of different complexes. In this case subtomograms must be classified. However, classification of large numbers of subtomograms is a time-intensive task and often a limiting bottleneck. This paper introduces an open source software platform, TomoMiner, for large-scale subtomogram classification, template matching, subtomogram averaging, and alignment. Its scalable and robust parallel processing allows efficient classification of tens to hundreds of thousands of subtomograms. In addition, TomoMiner provides a pre-configured TomoMinerCloud computing service permitting users without sufficient computing resources instant access to TomoMiners high-performance features.
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Affiliation(s)
- Zachary Frazier
- Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, 1050 Childs Way, Los Angeles, CA 90089, USA
| | - Min Xu
- Computational Biology Department, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
| | - Frank Alber
- Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, 1050 Childs Way, Los Angeles, CA 90089, USA.
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Hampton CM, Strauss JD, Ke Z, Dillard RS, Hammonds JE, Alonas E, Desai TM, Marin M, Storms RE, Leon F, Melikyan GB, Santangelo PJ, Spearman PW, Wright ER. Correlated fluorescence microscopy and cryo-electron tomography of virus-infected or transfected mammalian cells. Nat Protoc 2016; 12:150-167. [PMID: 27977021 DOI: 10.1038/nprot.2016.168] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Correlative light and electron microscopy (CLEM) combines spatiotemporal information from fluorescence light microscopy (fLM) with high-resolution structural data from cryo-electron tomography (cryo-ET). These technologies provide opportunities to bridge knowledge gaps between cell and structural biology. Here we describe our protocol for correlated cryo-fLM, cryo-electron microscopy (cryo-EM), and cryo-ET (i.e., cryo-CLEM) of virus-infected or transfected mammalian cells. Mammalian-derived cells are cultured on EM substrates, using optimized conditions that ensure that the cells are spread thinly across the substrate and are not physically disrupted. The cells are then screened by fLM and vitrified before acquisition of cryo-fLM and cryo-ET images, which is followed by data processing. A complete session from grid preparation through data collection and processing takes 5-15 d for an individual experienced in cryo-EM.
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Affiliation(s)
- Cheri M Hampton
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Joshua D Strauss
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Zunlong Ke
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Rebecca S Dillard
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Jason E Hammonds
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Eric Alonas
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, USA
| | - Tanay M Desai
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Mariana Marin
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Rachel E Storms
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Fredrick Leon
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Gregory B Melikyan
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Philip J Santangelo
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, USA
| | - Paul W Spearman
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Elizabeth R Wright
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, USA.,Robert P. Apkarian Integrated Electron Microscopy Core, Emory University, Atlanta, Georgia, USA
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