602 results match your criteria: "San Diego Supercomputer Center[Affiliation]"

Assessing PDB macromolecular crystal structure confidence at the individual amino acid residue level.

Structure

October 2022

Research Collaboratory for Structural Bioinformatics Protein Data Bank, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; Research Collaboratory for Structural Bioinformatics Protein Data Bank, San Diego Supercomputer Center, University of California San Diego, La Jolla, CA 92093, USA; Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA; Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA. Electronic address:

Approximately 87% of the more than 190,000 atomic-level three-dimensional (3D) biostructures in the PDB were determined using macromolecular crystallography (MX). Agreement between 3D atomic coordinates and experimental data for >100 million individual amino acid residues occurring within ∼150,000 PDB MX structures was analyzed in detail. The real-space correlation coefficient (RSCC) calculated using the 3D atomic coordinates for each residue and experimental-data-derived electron density enables outlier detection of unreliable atomic coordinates (particularly important for poorly resolved side-chain atoms) and ready evaluation of local structure quality by PDB users.

View Article and Find Full Text PDF

Establishing a blockchain-enabled Indigenous data sovereignty framework for genomic data.

Cell

July 2022

Global Health Program, Department of Anthropology, University of California, San Diego, San Diego, CA, USA; Native BioData Consortium, Eagle Butte, SD, USA; Indigenous Futures Institute, Division of Design and Innovation, University of California, San Diego, San Diego, CA, USA. Electronic address:

Technological advances have enabled the rapid generation of health and genomic data, though rarely do these technologies account for the values and priorities of marginalized communities. In this commentary, we conceptualize a blockchain genomics data framework built out of the concept of Indigenous Data Sovereignty.

View Article and Find Full Text PDF

Structure-selected RBM immunogens prime polyclonal memory responses that neutralize SARS-CoV-2 variants of concern.

PLoS Pathog

July 2022

The Laboratory of Immunology, Department of Medicine and Moores Cancer Center, University of California San Diego, La Jolla, California, United States of America.

Successful control of the COVID-19 pandemic depends on vaccines that prevent transmission. The full-length Spike protein is highly immunogenic but the majority of antibodies do not target the virus: ACE2 interface. In an effort to affect the quality of the antibody response focusing it to the receptor-binding motif (RBM) we generated a series of conformationally-constrained immunogens by inserting solvent-exposed RBM amino acid residues into hypervariable loops of an immunoglobulin molecule.

View Article and Find Full Text PDF

As efforts advance around the globe, the US falls behind.

View Article and Find Full Text PDF

Bcl2-associated athanogene 3 (BAG3) is a multifunctional cochaperone responsible for protein quality control within cells. BAG3 interacts with chaperones HSPB8 and Hsp70 to transport misfolded proteins to the Microtubule Organizing Center (MTOC) and degrade them in autophagosomes in a process known as Chaperone Assisted Selective Autophagy (CASA). Mutations in the second conserved IPV motif of BAG3 are known to cause Dilated Cardiomyopathy (DCM) by inhibiting adequate removal of non-native proteins.

View Article and Find Full Text PDF

Exploring protein symmetry at the RCSB Protein Data Bank.

Emerg Top Life Sci

September 2022

Research Collaboratory for Structural Bioinformatics Protein Data Bank, San Diego Supercomputer Center, University of California, San Diego, La Jolla, CA 92093, U.S.A.

The symmetry of biological molecules has fascinated structural biologists ever since the structure of hemoglobin was determined. The Protein Data Bank (PDB) archive is the central global archive of three-dimensional (3D), atomic-level structures of biomolecules, providing open access to the results of structural biology research with no limitations on usage. Roughly 40% of the structures in the archive exhibit some type of symmetry, including formal global symmetry, local symmetry, or pseudosymmetry.

View Article and Find Full Text PDF

Density functional theory (DFT) is the most widely used electronic structure method, due to its simplicity and cost effectiveness. The accuracy of a DFT calculation depends not only on the choice of the density functional approximation (DFA) adopted but also on the electron density produced by the DFA. SCAN is a modern functional that satisfies all known constraints for meta-GGA functionals.

View Article and Find Full Text PDF

Computer-aided drug design, quantum-mechanical methods for biological problems.

Curr Opin Struct Biol

August 2022

Department of Chemistry and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, United States. Electronic address:

Quantum chemistry enables to study systems with chemical accuracy (<1 kcal/mol from experiment) but is restricted to a handful of atoms due to its computational expense. This has led to ongoing interest to optimize and simplify these methods while retaining accuracy. Implementing quantum mechanical (QM) methods on modern hardware such as multiple-GPUs is one example of how the field is optimizing performance.

View Article and Find Full Text PDF

BIPSPI+: Mining Type-Specific Datasets of Protein Complexes to Improve Protein Binding Site Prediction.

J Mol Biol

June 2022

Research Collaboratory for Structural Bioinformatics, Protein Data Bank, San Diego Supercomputer Center, University of California San Diego, La Jolla, CA 92093, USA.

Computational approaches for predicting protein-protein interfaces are extremely useful for understanding and modelling the quaternary structure of protein assemblies. In particular, partner-specific binding site prediction methods allow delineating the specific residues that compose the interface of protein complexes. In recent years, new machine learning and other algorithmic approaches have been proposed to solve this problem.

View Article and Find Full Text PDF

Background: Approximately 30% of Candida genus isolates are resistant to all currently available antifungal drugs and it is highly important to develop new treatments. Additionally, many current drugs are toxic and cause unwanted side effects. 1,3-beta-glucan synthase is an essential enzyme that builds the cell walls of Candida.

View Article and Find Full Text PDF

Amino acids control blood glucose levels through mTOR signaling.

Eur J Cell Biol

August 2022

Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA; Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA. Electronic address:

Amino Acids are not only major nutrient sources, but also serve as chemical signals to control cellular growth. Rab1A recently emerged as a key component in amino acid sensing and signaling to activate the mTOR complex1 (mTORC1). In a recently published study [1], we generated tamoxifen-inducible, conditional whole-body Rab1A knockout in adult mice.

View Article and Find Full Text PDF

RCSB Protein Data Bank 1D3D module: displaying positional features on macromolecular assemblies.

Bioinformatics

June 2022

Research Collaboratory for Structural Bioinformatics Protein Data Bank, San Diego Supercomputer Center, University of California, La Jolla, CA 92093, USA.

Motivation: Mapping positional features from one-dimensional (1D) sequences onto three-dimensional (3D) structures of biological macromolecules is a powerful tool to show geometric patterns of biochemical annotations and provide a better understanding of the mechanisms underpinning protein and nucleic acid function at the atomic level.

Results: We present a new library designed to display fully customizable interactive views between 1D positional features of protein and/or nucleic acid sequences and their 3D structures as isolated chains or components of macromolecular assemblies.

Availability And Implementation: https://github.

View Article and Find Full Text PDF

Evaluation of immunogenic epitopes for universal vaccine development in the face of ongoing SARS-CoV-2 evolution remains a challenge. Herein, we investigate the genetic and structural conservation of an immunogenically relevant epitope (C662-C671) of spike (S) protein across SARS-CoV-2 variants to determine its potential utility as a broad-spectrum vaccine candidate against coronavirus diseases. Comparative sequence analysis, structural assessment, and molecular dynamics simulations of C662-C671 epitope were performed.

View Article and Find Full Text PDF

We investigate the interplay between functional-driven and density-driven errors in different density functional approximations within density functional theory (DFT) and the implications of these errors for simulations of water with DFT-based data-driven potentials. Specifically, we quantify density-driven errors in two widely used dispersion-corrected functionals derived within the generalized gradient approximation (GGA), namely BLYP-D3 and revPBE-D3, and two modern -GGA functionals, namely strongly constrained and appropriately normed (SCAN) and B97M-rV. The effects of functional-driven and density-driven errors on the interaction energies are first assessed for the water clusters of the BEGDB dataset.

View Article and Find Full Text PDF

Background: In the current COVID-19 pandemic, with an absence of approved drugs and widely accessible vaccines, repurposing existing drugs is vital to quickly developing a treatment for the disease.

Methods: In this study, we used a dataset consisting of sequences of viral proteins and chemical structures of pharmaceutical drugs for known drug-target interactions (DTIs) and artificially generated non-interacting DTIs to train a binary classifier with the ability to predict new DTIs. Random Forest (RF), deep neural network (DNN), and convolutional neural networks (CNN) were tested.

View Article and Find Full Text PDF

PDBx/mmCIF Ecosystem: Foundational Semantic Tools for Structural Biology.

J Mol Biol

June 2022

Research Collaboratory for Structural Bioinformatics Protein Data Bank, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA. Electronic address:

PDBx/mmCIF, Protein Data Bank Exchange (PDBx) macromolecular Crystallographic Information Framework (mmCIF), has become the data standard for structural biology. With its early roots in the domain of small-molecule crystallography, PDBx/mmCIF provides an extensible data representation that is used for deposition, archiving, remediation, and public dissemination of experimentally determined three-dimensional (3D) structures of biological macromolecules by the Worldwide Protein Data Bank (wwPDB, wwpdb.org).

View Article and Find Full Text PDF

Background: While mechanisms contributing to the progression and metastasis of colorectal cancer (CRC) are well studied, cancer stage-specific mechanisms have been less comprehensively explored. This is the focus of this manuscript.

Methods: Using previously published data for CRC (Gene Expression Omnibus ID GSE21510), we identified differentially expressed genes (DEGs) across four stages of the disease.

View Article and Find Full Text PDF
Article Synopsis
  • Researchers have been developing molecular models for 50 years to accurately replicate water's structure and properties across its complex phase diagram.
  • This study uses the MB-pol model to simulate liquid water's thermodynamic responses from boiling to supercooled temperatures, revealing key temperature points where certain properties peak or dip.
  • It highlights that the MB-pol model is promising for predicting water's physical properties, especially in difficult-to-study areas like "no man's land."
View Article and Find Full Text PDF

Motivation: Training domain-specific named entity recognition (NER) models requires high quality hand curated gold standard datasets which are time-consuming and expensive to create. Furthermore, the storage and memory required to deploy NLP models can be prohibitive when the number of tasks is large. In this work, we explore utilizing multi-task learning to reduce the amount of training data needed to train new domain-specific models.

View Article and Find Full Text PDF

Pfizer's Crystal Structure Database (CSDB) is a key enabling technology that allows scientists on structure-based projects rapid access to Pfizer's vast library of in-house crystal structures, as well as a significant number of structures imported from the Protein Data Bank. In addition to capturing basic information such as the asymmetric unit coordinates, reflection data, and the like, CSDB employs a variety of automated methods to first ensure a standard level of annotations and error checking, and then to add significant value for design teams by processing the structures through a sequence of algorithms that prepares the structures for use in modeling. The structures are made available, both as the original asymmetric unit as submitted, as well as the final prepared structures, through REST-based web services that are consumed by several client desktop applications.

View Article and Find Full Text PDF

Combined Theoretical, Bioinformatic, and Biochemical Analyses of RNA Editing by Adenine Base Editors.

CRISPR J

April 2022

Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA; University of California San Diego, La Jolla, California, USA.

Adenine base editors (ABEs) have been subjected to multiple rounds of mutagenesis with the goal of optimizing their function as efficient and precise genome editing agents. Despite an ever-expanding data set of ABE mutants and their corresponding DNA or RNA-editing activity, the molecular mechanisms defining these changes remain to be elucidated. In this study, we provide a systematic interpretation of the nature of these mutations using an entropy-based classification model that relies on evolutionary data from extant protein sequences.

View Article and Find Full Text PDF

Mutant superoxide dismutase 1 (SOD1) may form cyclic structures due to its greater instability from aberrant demetallization and oxidation of cysteine bonds. This cyclic structure may allow SOD1 to form ion channels on membranes such as the mitochondrial membrane, causing imbalances in the concentration of intracellular ions as a potential mechanism for the progressive neuron death involved in amyotrophic lateral sclerosis (ALS). Using docking programs within modeling software, models of mutant SOD1 dimers and eventually ring oligomers were constructed based on known descriptions of such structures in addition to information on the orientation of the models associated with a membrane.

View Article and Find Full Text PDF
Article Synopsis
  • The uptake of nitrogen oxide (NO) into water-based aerosols is a significant process for nitrogen oxides' reduction in the atmosphere, but its detailed mechanisms are not fully understood.
  • Using advanced molecular dynamics simulations, researchers were able to analyze how NO interacts with water, finding that it tends to stick to the interface between air and water and is not easily absorbed into the bulk water.
  • The simulations led to important findings on reaction rates and solubility, providing a basis for understanding how NO reacts in more complicated mixtures beyond pure water.
View Article and Find Full Text PDF