102 research outputs found
A Primary Resource for the Restoration, Reconstruction and/or Replication of 18th and Early 19th Century Architectural Elements: The Architectural Study Collection of Independence National Historical Park
Transformer-based molecular optimization beyond matched molecular pairs
Molecular optimization aims to improve the drug profile of a starting molecule. It is a fundamental problem in drug discovery but challenging due to (i) the requirement of simultaneous optimization of multiple properties and (ii) the large chemical space to explore. Recently, deep learning methods have been proposed to solve this task by mimicking the chemist\u27s intuition in terms of matched molecular pairs (MMPs). Although MMPs is a widely used strategy by medicinal chemists, it offers limited capability in terms of exploring the space of structural modifications, therefore does not cover the complete space of solutions. Often more general transformations beyond the nature of MMPs are feasible and/or necessary, e.g. simultaneous modifications of the starting molecule at different places including the core scaffold. This study aims to provide a general methodology that offers more general structural modifications beyond MMPs. In particular, the same Transformer architecture is trained on different datasets. These datasets consist of a set of molecular pairs which reflect different types of transformations. Beyond MMP transformation, datasets reflecting general structural changes are constructed from ChEMBL based on two approaches: Tanimoto similarity (allows for multiple modifications) and scaffold matching (allows for multiple modifications but keep the scaffold constant) respectively. We investigate how the model behavior can be altered by tailoring the dataset while using the same model architecture. Our results show that the models trained on differently prepared datasets transform a given starting molecule in a way that it reflects the nature of the dataset used for training the model. These models could complement each other and unlock the capability for the chemists to pursue different options for improving a starting molecule
ProteinsPlus: a web portal for structure analysis of macromolecules
With currently more than 126 000 publicly available structures and an
increasing growth rate, the Protein Data Bank constitutes a rich data source
for structure-driven research in fields like drug discovery, crop science and
biotechnology in general. Typical workflows in these areas involve manifold
computational tools for the analysis and prediction of molecular functions.
Here, we present the ProteinsPlus web server that offers a unified easy-to-use
interface to a broad range of tools for the early phase of structure-based
molecular modeling. This includes solutions for commonly required pre-
processing tasks like structure quality assessment (EDIA), hydrogen placement
(Protoss) and the search for alternative conformations (SIENA). Beyond that,
it also addresses frequent problems as the generation of 2D-interaction
diagrams (PoseView), proteinâprotein interface classification (HyPPI) as well
as automatic pocket detection and druggablity assessment (DoGSiteScorer). The
unified ProteinsPlus interface covering all featured approaches provides
various facilities for intuitive input and result visualization, case-specific
parameterization and download options for further processing. Moreover, its
generalized workflow allows the user a quick familiarization with the
different tools. ProteinsPlus also stores the calculated results temporarily
for future request and thus facilitates convenient result communication and
re-access. The server is freely available at http://proteins.plus
DockStream: a docking wrapper to enhance de novo molecular design
Recently, we have released the de novo design platform REINVENT in version 2.0. This improved and extended iteration supports far more features and scoring function components, which allows bespoke and tailor-made protocols to maximize impact in small molecule drug discovery projects. A major obstacle of generative models is producing active compounds, in which predictive (QSAR) models have been applied to enrich target activity. However, QSAR models are inherently limited by their applicability domains. To overcome these limitations, we introduce a structure-based scoring component for REINVENT. DockStream is a flexible, stand-alone molecular docking wrapper that provides access to a collection of ligand embedders and docking backends. Using the benchmarking and analysis workflow provided in DockStream, execution and subsequent analysis of a variety of docking configurations can be automated. Docking algorithms vary greatly in performance depending on the target and the benchmarking and analysis workflow provides a streamlined solution to identifying productive docking configurations. We show that an informative docking configuration can inform the REINVENT agent to optimize towards improving docking scores using public data. With docking activated, REINVENT is able to retain key interactions in the binding site, discard molecules which do not fit the binding cavity, harness unused (sub-)pockets, and improve overall performance in the scaffold-hopping scenario. The code is freely available at https://github.com/MolecularAI/DockStream
Peregrine and saker falcon genome sequences provide insights into evolution of a predatory lifestyle
As top predators, falcons possess unique morphological, physiological and behavioral adaptations that allow them to be successful hunters: for example, the peregrine is renowned as the world's fastest animal. To examine the evolutionary basis of predatory adaptations, we sequenced the genomes of both the peregrine (Falco peregrinus) and saker falcon (Falco cherrug), and we present parallel, genome-wide evidence for evolutionary innovation and selection for a predatory lifestyle. The genomes, assembled using Illumina deep sequencing with greater than 100-fold coverage, are both approximately 1.2 Gb in length, with transcriptome-assisted prediction of approximately 16,200 genes for both species. Analysis of 8,424 orthologs in both falcons, chicken, zebra finch and turkey identified consistent evidence for genome-wide rapid evolution in these raptors. SNP-based inference showed contrasting recent demographic trajectories for the two falcons, and gene-based analysis highlighted falcon-specific evolutionary novelties for beak development and olfaction and specifically for homeostasis-related genes in the arid environmentâadapted saker
Determination of optimal glucose concentration for microcalorimetric metabolic evaluation of equine spermatozoa
Detektion verborgener Objekte mittels eines abbildenden Terahertz-HeterodynempfÀngers (Detection of Hidden Objects with an Imaging Terahertz Heterodyne Receiver)
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