Recombinant proteasome provides new avenues for anti-malarial drug development.

The 20S proteasome (Pf20S) is a promising antimalarial target. Therapeutic development has previously relied on native purifications of Pf20S, which is challenging and has limited the scope of previous efforts. Here, we report an effective recombinant Pf20S platform to facilitate drug discovery.

Cyanobacteria Join the Kahalalide Conversation: Genome and Metabolite Evidence for Structurally Related Peptides.

Kahalalide F is a cyclic depsipeptide with notable anticancer properties, initially discovered from the green alga sp. and its molluscan predator . Recent studies have pinpointed a bacterial endosymbiont of the green alga, Endobryopsis kahalalidefaciens, as the true producer of kahalalide F.

Neutral pH-Selective Inhibition of Cytosolic Cathepsin B: A Novel Drug Targeting Strategy for Traumatic Brain Injury and Alzheimer's Disease.

Cathepsin B contributes to the behavioral deficits and neuropathology that occur in traumatic brain injury (TBI) and Alzheimer's disease (AD). TBI and AD patients display elevated levels of cathepsin B that correlate with the severity of injury or cognitive deficits, respectively. In animal models of TBI and AD, cathepsin B gene knockout ameliorates behavioral deficits and improves neuropathology.

Green genes from blue greens: challenges and solutions to unlocking the potential of cyanobacteria in drug discovery.

Cyanobacteria are prolific producers of biologically active compounds that are important in influencing ecology, behavior of interacting organisms, and as leads in drug discovery efforts. Here we discuss the challenges faced by all natural product researchers, especially those that focus on cyanobacteria, and then describe progress that has been made in these areas. We also propose some solutions, paths forward, and thoughts for consideration on these challenges.

Quorum quenching of phenolic compounds from Leptolyngbya spp. MACC 32 via downregulation of the periplasmic receptor LuxP in Vibrio harveyi: Hinting a putative mechanism.

Vibrio harveyi causes vibriosis, leading to high mortality and economic loss in global aquaculture. Quorum sensing (QS) driven biofilm formation makes them more resistant to various control measures. This study examined QS inhibition (QSI) of V.

A universal language for finding mass spectrometry data patterns.

Despite being information rich, the vast majority of untargeted mass spectrometry data are underutilized; most analytes are not used for downstream interpretation or reanalysis after publication. The inability to dive into these rich raw mass spectrometry datasets is due to the limited flexibility and scalability of existing software tools. Here we introduce a new language, the Mass Spectrometry Query Language (MassQL), and an accompanying software ecosystem that addresses these issues by enabling the community to directly query mass spectrometry data with an expressive set of user-defined mass spectrometry patterns.

Activation of Cytosolic Cathepsin B Activity in the Brain by Traumatic Brain Injury and Inhibition by the Neutral pH Selective Inhibitor Probe Z-Arg-Lys-AOMK.

Cathepsin B has been shown to contribute to deficits in traumatic brain injury (TBI), an important risk factor for Alzheimer's disease (AD). Cathepsin B is elevated in TBI and AD patients, as well as in animal models of these conditions. Knockout of the cathepsin B gene results in amelioration of TBI-induced motor dysfunction and improvement of AD memory deficit in mice.

Structure of a putative terminal amidation domain in natural product biosynthesis.

Bacteria are rich sources of pharmaceutically valuable natural products, many crafted by modular polyketide synthases (PKS) and non-ribosomal peptide synthetases (NRPS). PKS and NRPS systems typically contain a thioesterase (TE) to offload a linear or cyclized product from a carrier protein, but alternative chemistry is needed for products with a terminal amide. Several pathways with amidated products also possess an uncharacterized 400-amino acid terminal domain.

Isolation and Biosynthesis of Hyellamide, a Glycosylated N-Acyltyrosine Derivative, from the Cyanobacterium LEGE 07179.

Recent analyses of genome data indicate that members of the cyanobacterial order Pleurocapsales show tremendous potential for natural product discovery. However, only a few compounds have been reported from this order. Here, we report the isolation of hyellamide (), a glycosylated N-acyl tyrosine-derived eneamide, from the pleurocapsalean cyanobacterium LEGE 07179.

Fatuamide A, a Hybrid PKS/NRPS Metallophore from a sp. Marine Cyanobacterium Collected in American Samoa.

A structurally novel metabolite, fatuamide A (), was discovered from a laboratory cultured strain of the marine cyanobacterium sp., collected from Faga'itua Bay, American Samoa. A bioassay-guided approach using NCI-H460 human lung cancer cells directed the isolation of fatuamide A, which was obtained from the most cytotoxic fraction.

Carmaphycin B-Based Proteasome Inhibitors to Treat Human African Trypanosomiasis: Structure-Activity Relationship and Efficacy.

The proteasome is essential for eukaryotic cell proteostasis, and inhibitors of the 20S proteasome are progressing preclinically and clinically as antiparasitics. We screened, the causative agent of human and animal African trypanosomiasis, with a set of 27 carmaphycin B analogs, irreversible epoxyketone inhibitors that were originally developed to inhibit the20S (Pf20S). The structure-activity relationship was distinct from that of the human c20S antitarget by the acceptance of d-amino acids at the P3 position of the peptidyl backbone to yield compounds with greatly decreased toxicity to human cells.

Evaluating Antimalarial Proteasome Inhibitors for Efficacy in Blood Stage Cultures.

Tick-transmitted are a major global veterinary threat and an emerging risk to humans. Unlike their relatives, these erythrocyte-infecting Apicomplexa have been largely overlooked and lack specific treatment. Selective targeting of the proteasome holds promise for drug development.

Sea-Air Transfer of Phycotoxins Is Driven by the Chemical Diversity of the Particulate Fraction in the Surface Microlayer.

Blooms of cf. pose an emerging health threat, causing respiratory disorders in various coastal regions. This dinoflagellate produce potent phycotoxins named ovatoxins that can be transferred from the seawater to the atmosphere.

Structural elucidation of recombinant Trichomonas vaginalis 20S proteasome bound to covalent inhibitors.

The proteasome is a proteolytic enzyme complex essential for protein homeostasis in mammalian cells and protozoan parasites like Trichomonas vaginalis (Tv), the cause of the most common, non-viral sexually transmitted disease. Tv and other protozoan 20S proteasomes have been validated as druggable targets for antimicrobials. However, low yields and purity of the native proteasome have hindered studies of the Tv 20S proteasome (Tv20S).

Light-gated integrator for highlighting kinase activity in living cells.

Protein kinases are key signaling nodes that regulate fundamental biological and disease processes. Illuminating kinase signaling from multiple angles can provide deeper insights into disease mechanisms and improve therapeutic targeting. While fluorescent biosensors are powerful tools for visualizing live-cell kinase activity dynamics in real time, new molecular tools are needed that enable recording of transient signaling activities for post hoc analysis and targeted manipulation.

Leptochelins A-C, Cytotoxic Metallophores Produced by Geographically Dispersed Strains of Marine Cyanobacteria.

Metals are important cofactors in the metabolic processes of cyanobacteria, including photosynthesis, cellular respiration, DNA replication, and the biosynthesis of primary and secondary metabolites. In adaptation to the marine environment, cyanobacteria use metallophores to acquire trace metals when necessary as well as to reduce potential toxicity from excessive metal concentrations. Leptochelins A-C were identified as structurally novel metallophores from three geographically dispersed cyanobacteria of the genus .

The Kavaratamides: Discovery of Linear Lipodepsipeptides from the Marine Cyanobacterium Using a Comparative Chemogeographic Analysis.

Kavaratamide A (), a new linear lipodepsipeptide possessing an unusual isopropyl--methylpyrrolinone moiety, was discovered from the tropical marine filamentous cyanobacterium collected from Kavaratti, India. A comparative chemogeographic analysis of . collected from six different geographical regions led to the prioritized isolation of this metabolite from India as distinctive among our data sets.

Nature-Inspired Gallinamides Are Potent Antischistosomal Agents: Inhibition of the Cathepsin B1 Protease Target and Binding Mode Analysis.

Schistosomiasis, caused by a parasitic blood fluke of the genus is a global health problem for which new chemotherapeutic options are needed. We explored the scaffold of gallinamide A, a natural peptidic metabolite of marine cyanobacteria that has previously been shown to inhibit cathepsin L-type proteases. We screened a library of 19 synthetic gallinamide A analogs and identified nanomolar inhibitors of the cathepsin B-type protease SmCB1, which is a drug target for the treatment of schistosomiasis mansoni.

Light-gated Integrator for Highlighting Kinase Activity in Living Cells.

Protein kinases are key signaling nodes that regulate fundamental biological and disease processes. Illuminating kinase signaling from multiple angles can provide deeper insights into disease mechanisms and improve therapeutic targeting. While fluorescent biosensors are powerful tools for visualizing live-cell kinase activity dynamics in real time, new molecular tools are needed that enable recording of transient signaling activities for post hoc analysis and targeted manipulation.

PECAN Predicts Patterns of Cancer Cell Cytostatic Activity of Natural Products Using Deep Learning.

Many machine learning techniques are used as drug discovery tools with the intent to speed characterization by determining relationships between compound structure and biological function. However, particularly in anticancer drug discovery, these models often make only binary decisions about the biological activity for a narrow scope of drug targets. We present a feed-forward neural network, PECAN (Prediction Engine for the Cytostatic Activity of Natural product-like compounds), that simultaneously classifies the potential antiproliferative activity of compounds against 59 cancer cell lines.