254 research outputs found
Crystal structure of thebaine 6-O-demethylase from the morphine biosynthesis pathway
Thebaine 6-O-demethylase (T6ODM) from Papaver somniferum (opium poppy) is a key enzyme in the
morphine biosynthesis pathway that belongs to the non-heme 2-oxoglutarate/Fe(II)-dependent
dioxygenases (ODD) family. Initially, T6ODM was characterized as an enzyme catalyzing Odemethylation
of thebaine to neopinone and oripavine to morphinone, however recently the substrate range
of T6ODM was expanded to a number of various benzylisoquinoline alkaloids. Here, we present crystal
structures of T6ODM in complexes with 2-oxoglutarate (T6ODM:2OG, PDB: 5O9W) and succinate
(T6ODM:SIN, PDB: 5O7Y). The arrangement of the T6ODMâs active site is typical for proteins from the
ODD family, but the enzyme is characterized by a large substrate binding cavity, whose volume can
partially explain the T6ODM promiscuity. Moreover, the size of the cavity allows for binding of multiple
molecules at once, posing a question about substrate-driven specificity of the enzyme
A bispecific monomeric nanobody induces spike trimer dimers and neutralizes SARS-CoV-2 in vivo
Experiments with replication-competent SARS-CoV-2 were performed in the Biomedicum BSL3 core facility, Karolinska Institutet. We thank Jonas Klingström for providing Calu-3 cells and sharing the Swedish SARS-CoV-2 isolate, and Alex Sigal from the Africa Health Research Institute for providing the beta variant (B.1.351/501Y.V2) isolate. We thank Penny Moore and the NICD (South Africa) for providing the B.1.351/beta variant spike plasmid, which was generated using funding from the South African Medical Research Council. We gratefully acknowledge the G2P-UK National Virology consortium funded by MRC/UKRI (grant ref: MR/W005611/1.) and the Barclay Lab at Imperial College for providing the B.1.617.2 spike plasmid. All cryo-EM data were collected in the Karolinska Institutetâs 3D-EM facility. We thank Agustin Ure for assistance with figure generation and Tomas Nyman (Protein Science Facility at KI) for providing access to SPR instruments. L.H. was supported by the David och Astrid HagelĂ©ns stiftelse, the Clas Groschinskys Minnesfond and a Jonas Söderquistâs scholarship. This project has received funding from the European Unionâs Horizon 2020 research and innovation program under grant agreement No. 101003653 (CoroNAb), to B.M. and G.M.M. B.M.H. is supported by the Knut and Alice Wallenberg Foundation (KAW 2017.0080 and KAW 2018.0080). The work was supported by project grants from the Swedish Research Council to E.S. (2020-02682), B.M.H. (2017-6702 and 2018-3808), B.M. (2018-02381) and to G.M.M. (2018-03914 and 2018-03843). E.S. is supported by Karolinska Institutet Foundation Grants, National Molecular Medicine Program Grants, and the grants from the SciLifeLab National COVID-19 Research Program, financed by the Knut and Alice Wallenberg Foundation. We thank National Microscopy Infrastructure, NMI (VR-RFI 2016-00968).N
Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94846/1/palo900.pd
Key determinants of selective binding and activation by the monocyte chemoattractant proteins at the chemokine receptor CCR2
Chemokines and their receptors collectively orchestrate the trafficking of leukocytes in normal immune function and inflammatory diseases. Different chemokines can induce distinct responses at the same receptor. In comparison to monocyte chemoattractant protein-1 (MCP-1; also known as CCL2), the chemokines MCP-2 (CCL8) and MCP-3 (CCL7) are partial agonists of their shared receptor CCR2, a key regulator of the trafficking of monocytes and macrophages that contribute to the pathology of atherosclerosis, obesity, and type 2 diabetes. Through experiments with chimeras of MCP-1 and MCP-3, we identified the chemokine amino-terminal region as being the primary determinant of both the binding and signaling selectivity of these two chemokines at CCR2. Analysis of CCR2 mutants showed that the chemokine amino terminus interacts with the major subpocket in the transmembrane helical bundle of CCR2, which is distinct fromthe interactions of some other chemokines with the minor subpockets of their receptors. These results suggest the major subpocket as a target for the development of small-molecule inhibitors of CCR2. 2017 © The Authors
ISAMBARD:An open-source computational environment for biomolecular analysis, modelling and design
Motivation: The rational design of biomolecules is becoming a reality. However, further computational tools are needed to facilitate and accelerate this, and to make it accessible to more users.
Results: Here we introduce ISAMBARD, a tool for structural analysis, model building and rational design of biomolecules. ISAMBARD is open-source, modular, computationally scalable and intuitive to use. These features allow non-experts to explore biomolecular design in silico. ISAMBARD addresses a standing issue in protein design, namely, how to introduce backbone variability in a controlled manner. This is achieved through the generalization of tools for parametric modelling, describing the overall shape of proteins geometrically, and without input from experimentally determined structures. This will allow backbone conformations for entire folds and assemblies not observed in nature to be generated de novo, that is, to access the âdark matter of protein-fold spaceâ. We anticipate that ISAMBARD will find broad applications in biomolecular design, biotechnology and synthetic biology.
Availability and implementation: A current stable build can be downloaded from the python package index (https://pypi.python.org/pypi/isambard/) with development builds available on GitHub (https://github.com/woolfson-group/) along with documentation, tutorial material and all the scripts used to generate the data described in this paper.
Contact:[email protected] or [email protected]
Supplementary information:Supplementary data are available at Bioinformatics online
A Core Outcome Set for Efficacy of Acute Treatment of Hereditary Angioedema
BACKGROUND: Clinical trials investigating drugs for the acute treatment of hereditary angioedema attacks have assessed many different outcomes. This heterogeneity limits the comparability of trial results and may lead to selective outcome reporting bias and a high burden on trial participants. OBJECTIVE: To achieve consensus on a core outcome set composed of key outcomes that ideally should be used in all clinical efficacy trials involving the acute treatment of hereditary angioedema attacks. METHODS: We conducted a Delphi consensus study involving all relevant parties: patients with hereditary angioedema, hereditary angioedema expert clinicians and clinical researchers, pharmaceutical companies, and regulatory bodies. Two Internetbased survey rounds were conducted. In round 1, panelists indicated the importance of individual outcomes used in clinical trials on a 9 -point Likert scale. Based on these results, a core outcome set was developed and voted on by panelists in round 2. RESULTS: A total of 58 worldwide panelists completed both rounds. The fi rst round demonstrated high importance scores and substantial agreement among the panelists. In the second round, a consensus of 90% or greater was achieved on a core outcome set consisting of fi ve key outcomes: change in overall symptom severity at one predetermined time point between 15 minutes and 4 hours after treatment, time to end of progression of all symptoms, the need for rescue medication during the entire attack, impairment of daily activities, and treatment satisfaction. CONCLUSIONS: This international study obtained a high level of consensus on a core outcome set for the acute treatment of hereditary angioedema attacks, consisting of fi ve key outcomes. Crown Copyright (c) 2024 Published by Elsevier Inc. on behalf of the American Academy of Allergy, Asthma & Immunology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). (J Allergy Clin Immunol Pract 2024;12:1614-21
The international WAO/EAACI guideline for the management of hereditary angioedema - The 2021 revision and update.
Hereditary Angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2), by providing guidance on common and important clinical issues, such as: 1) How should HAE be diagnosed? 2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? 3) What are the goals of treatment? 4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast feeding women? 5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients
The international WAO/EAACI guideline for the management of hereditary angioedemaâThe 2021 revision and update
Hereditary angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1 inhibitor (type 1) and HAE with dysfunctional C1 inhibitor (type 2), by providing guidance on common and important clinical issues, such as: (1) How should HAE be diagnosed? (2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? (3) What are the goals of treatment? (4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast-feeding women? and (5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients
Identification, characterization, and gene expression analysis of nucleotide binding site (NB)-type resistance gene homologues in switchgrass
Abstract
Background
Switchgrass (Panicum virgatum L.) is a warm-season perennial grass that can be used as a second generation bioenergy crop. However, foliar fungal pathogens, like switchgrass rust, have the potential to significantly reduce switchgrass biomass yield. Despite its importance as a prominent bioenergy crop, a genome-wide comprehensive analysis of NB-LRR disease resistance genes has yet to be performed in switchgrass.
Results
In this study, we used a homology-based computational approach to identify 1011 potential NB-LRR resistance gene homologs (RGHs) in the switchgrass genome (v 1.1). In addition, we identified 40 RGHs that potentially contain unique domains including major sperm protein domain, jacalin-like binding domain, calmodulin-like binding, and thioredoxin. RNA-sequencing analysis of leaf tissue from ĂąâŹËAlamoĂąâŹâą, a rust-resistant switchgrass cultivar, and ĂąâŹËDacotahĂąâŹâą, a rust-susceptible switchgrass cultivar, identified 2634 high quality variants in the RGHs between the two cultivars. RNA-sequencing data from field-grown cultivar ĂąâŹËSummerĂąâŹâą plants indicated that the expression of some of these RGHs was developmentally regulated.
Conclusions
Our results provide useful insight into the molecular structure, distribution, and expression patterns of members of the NB-LRR gene family in switchgrass. These results also provide a foundation for future work aimed at elucidating the molecular mechanisms underlying disease resistance in this important bioenergy crop
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