Phytate metabolism is mediated by microbial cross-feeding in the gut microbiota

Nature Microbiology, Год журнала: 2024, Номер 9(7), С. 1812 - 1827

Опубликована: Июнь 10, 2024

Язык: Английский

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The inositol phosphate signalling network in physiology and disease

Trends in Biochemical Sciences, Год журнала: 2024, Номер unknown

Опубликована: Сен. 1, 2024

Язык: Английский

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Biochemical and biophysical characterization of inositol-tetrakisphosphate 1-kinase inhibitors

Journal of Biological Chemistry, Год журнала: 2025, Номер 301(3), С. 108274 - 108274

Опубликована: Фев. 7, 2025

Inositol phosphates (IPs) and inositol pyrophosphate play critical roles in many biological processes such as signaling molecules pathways responsible for cellular functions involved growth maintenance. The biosynthesis of IPs is carried out by a family phosphate kinases. In mammals, tetrakisphosphate kinase-1 (ITPK1) phosphorylates inositol-1,3,4-trisphosphate (Ins(1,3,4)P3) inositol-3,4,5,6-tetrakisphosphate (IP4), generating inositol-1,3,4,5,6-pentakisphosphate (IP5), which can be further phosphorylated to become hexakisphosphate (IP6). ITPK1 also possesses phosphatase activity that convert IP5 back IP4; therefore, may serve regulatory step IP6 production. utilization has been implicated fundamental sustainability are severely perturbed disease states including RNA editing, DNA repair, chromatin structure organization, ubiquitin ligation. Therefore, ITPK1, with no known inhibitors the literature, potential molecular target modulating important several human diseases. By independently coupling kinase activities luciferase activity, we have developed used biochemical high-throughput assays discover eight inhibitors. Further analysis revealed three these leads inhibit an ATP-competitive manner, low micromolar nanomolar affinities. We demonstrate most potent inhibitor regulate activity. determined crystal complex this at resolution 2.25 Å. This work provides insight into design next-generation

Язык: Английский

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Synthesis of a New Purine Analogue Class with Antifungal Activity and Improved Potency against Fungal IP_3–4K

ACS Infectious Diseases, Год журнала: 2025, Номер unknown

Опубликована: Март 31, 2025

New antifungals are urgently needed to treat deadly fungal infections. Targeting the inositol polyphosphate kinases IP3–4K (Arg1) and IP6K (Kcs1) is a promising strategy as it has been validated genetically be crucial for virulence but never pharmacologically. We now report synthesis of DT-23, an analogue N2-(m-trifluorobenzylamino)-N6-(p-nitrobenzylamino)purine (TNP), demonstrate that more potently inhibits recombinant Arg1 from priority pathogen Cryptococcus neoformans (Cn) (IC50 = 0.6 μM) than previous analogues 10–30 μM). DT-23 also Kcs1 with similar potency 0.68 activity in vivo. Unlike analogues, growth (MIC50 15 μg/mL) only 1.5 μg/mL synergizes Amphotericin B kill Cn vitro. DT-23/Amphotericin protective against infection insect model compared each drug alone. Transcription profiling shows impacts early stages IP cellular functions impacted by IPK gene deletion, consistent its targeted effect. This study establishes first pharmacological link between inhibiting antifungal activity, providing tools studying function foundation potentially develop new class drug.

Язык: Английский

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Generation of inositol polyphosphates through a phospholipase C-independent pathway involving carbohydrate and sphingolipid metabolism in Trypanosoma cruzi

mBio, Год журнала: 2025, Номер unknown

Опубликована: Апрель 2, 2025

Inositol phosphates are involved in a myriad of biological roles and activities such as Ca2+ signaling, phosphate homeostasis, energy metabolism, disease pathogenicity. In Saccharomyces cerevisiae, synthesis inositol occurs through the phosphoinositide phospholipase C (PLC)-catalyzed hydrolysis phosphatidylinositol 4,5-bisphosphate (PIP2) into 1,4,5-trisphosphate (IP3) diacylglycerol further IP3 phosphorylation by additional kinases that leads to formation highly phosphorylated derivatives, known pyrophosphates. Inositol-tetrakisphosphate 1-kinase (ITPK1) is an enzyme mediates PLC-independent polyphosphate monophosphates other intermediates cytosol. this work, we identified characterized Trypanosoma cruzi ITPK1 (TcITPK1) homolog. The ability TcITPK1 act mediator for alternative pathway was established plc1Δ isc1Δ yeast complementation assays SAX-HPLC analyses radioactively labeled inositol. localizes cytosol, knockout attempts revealed only one allele replaced DNA donor cassette at specific locus, suggesting null alleles may have lethal effects epimastigotes. Ablation T. 1 (TcPI-PLC1) affected from glucose 6-phosphate but did not affect polyphosphates, while ablation phosphosphingolipid (TcISC1) thus revealing using either or phosphoceramide PLC-dependent needed signaling. Millions people infected with cruzi, current treatment satisfactory. pyrophosphates been important signaling molecules. Our work demonstrates presence C-independent cruzi. Furthermore, demonstrate starts phosphoceramide, linking it carbohydrate sphingolipid metabolism. essentiality survival infective stages makes ideal drug target treating American trypanosomiasis.

Язык: Английский

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Pools of Independently Cycling Inositol Phosphates Revealed by Pulse Labeling with ¹⁸O-Water

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Май 15, 2025

Inositol phosphates control many central processes in eukaryotic cells including nutrient availability, growth, and motility. Kinetic resolution of a key modulator their signaling functions, the turnover phosphate groups on inositol ring, has been hampered by slow uptake, high dilution, constraining growth conditions radioactive pulse-labeling approaches. Here, we demonstrate rapid (seconds to minutes) nonradioactive labeling strategy polyphosphates through 18O-water yeast, human cells, amoeba, which can be applied any media. In combination with capillary electrophoresis mass spectrometry, simultaneously dissects vivo group dynamics broad spectrum even rare phosphates. The good temporal allowed us discover vigorous exchanges some pyrophosphates, whereas others remain remarkably inert. We propose model biosynthetic pathway pyrophosphates is organized distinct, kinetically separated pools. While transfer compounds between those pools slow, each pool undergoes internal cycling. This might enable perform distinct functions while being metabolically connected.

Язык: Английский

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Pools of independently cycling inositol phosphates revealed by pulse labeling with¹⁸O-water

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Май 3, 2024

Abstract Inositol phosphates control many central processes in eukaryotic cells, including nutrient availability, growth, and motility. Kinetic resolution of a key modulator their signaling functions, the turnover phosphate groups on inositol ring, has been hampered by slow uptake, high dilution, constraining growth conditions radioactive pulse-labeling approaches. Here, we demonstrate rapid (seconds to minutes), non-radioactive labeling polyphosphates through 18 O-water yeast, amoeba human which can be applied any media. In combination with capillary electrophoresis mass spectrometry, simultaneously dissects vivo group dynamics broad spectrum even rare phosphates. The improved temporal allowed us discover vigorous exchanges some poly- pyrophosphates, whereas others remain remarkably inert. Our observations support model biosynthetic pathway pyrophosphates is organized distinct, kinetically separated pools. While transfer compounds between those pools slow, each pool undergoes internal cycling. This might enable perform distinct functions while being metabolically connected.

Язык: Английский

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Inositol pyrophosphate catabolism by three families of phosphatases regulates plant growth and development

PLoS Genetics, Год журнала: 2024, Номер 20(11), С. e1011468 - e1011468

Опубликована: Ноя. 12, 2024

Inositol pyrophosphates (PP-InsPs) are nutrient messengers whose cellular levels precisely regulated. Diphosphoinositol pentakisphosphate kinases (PPIP5Ks) generate the active signaling molecule 1,5-InsP 8 . PPIP5Ks harbor phosphatase domains that hydrolyze PP-InsPs. Plant and Fungi Atypical Dual Specificity Phosphatases (PFA-DSPs) NUDIX phosphatases (NUDTs) also involved in PP-InsP degradation. Here, we analyze relative contributions of three different families to plant catabolism. We report biochemical characterization inositol pyrophosphate from Arabidopsis Marchantia polymorpha Overexpression PFA-DSP NUDT enzymes affects leads stunted growth phenotypes Arabidopsis. nudt17/18/21 knock-out mutants have altered pools gene expression patterns, but no apparent defects. In contrast, Mp pfa-dsp1 ge , nudt1 vip1 display severe developmental associated changes levels. Analysis supports a role for PP-InsPs phosphate signaling, additional functions nitrate homeostasis cell wall biogenesis. Simultaneous elimination two activities enhanced observed phenotypes. Taken together, PPIP5K, regulate development by collectively shaping pools.

Язык: Английский

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Bacterial Pathogen Infection Triggers Magic Spot Nucleotide Signaling in Arabidopsis thaliana Chloroplasts through Specific RelA/SpoT Homologues

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(29), С. 16081 - 16089

Опубликована: Июль 12, 2023

Magic spot nucleotides (p)ppGpp are important signaling molecules in bacteria and plants. In the latter, RelA-SpoT homologue (RSH) enzymes responsible for turnover. Profiling of is more difficult plants than due to lower concentrations severe matrix effects. Here, we report that capillary electrophoresis mass spectrometry (CE-MS) can be deployed study abundance identity Arabidopsis thaliana. This goal achieved by combining a titanium dioxide extraction protocol pre-spiking with chemically synthesized stable isotope-labeled internal reference compounds. The high sensitivity separation efficiency CE-MS enables monitoring changes levels A. thaliana upon infection pathogen Pseudomonas syringae pv. tomato (PstDC3000). We observed significant increase ppGpp post also stimulated flagellin peptide flg22 only. depends on functional receptor FLS2 its interacting kinase BAK1 indicating pathogen-associated molecular pattern (PAMP) receptor-mediated controls levels. Transcript analyses showed an upregulation RSH2 treatment both RSH3 after PstDC3000 infection. mutants deficient activity display no accumulation treatment, supporting involvement these synthases PAMP-triggered innate immune responses pathogens within chloroplast.

Язык: Английский

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Arg1 from Cryptococcus neoformans lacks PI3 kinase activity and conveys virulence roles via its IP _3-4 kinase activity

mBio, Год журнала: 2024, Номер 15(6)

Опубликована: Май 14, 2024

Inositol tris/tetrakis phosphate kinases (IP3-4K) in the human fungal priority pathogens, Cryptococcus neoformans (CnArg1) and Candida albicans (CaIpk2), convey numerous virulence functions, yet it is not known whether IP3-4K catalytic activity or a scaffolding role responsible. We therefore generated C. strain with non-functional kinase, referred to as dead-kinase (dk) CnArg1 (dkArg1). verified that, although dkARG1 cDNA cloned from this produced protein expected molecular weight, dkArg1 was catalytically inactive no activity. Using recombinant CaIpk2, we confirmed unlike homologs humans Saccharomyces cerevisiae, CaIpk2 do phosphorylate lipid-based substrate, phosphatidylinositol 4,5-bisphosphate, function class I PI3Ks. polyphosphate profiling using capillary electrophoresis-electrospray ionization-mass spectrometry revealed that IP3 conversion blocked ARG1 deletion (Cnarg1Δ) strains 1-IP7 recently discovered isomer (4/6-IP7) are made by wild-type neoformans. Importantly, Cnarg1Δ had similar defects, including suppressed growth at 37°C, melanization, capsule production, starvation response, were avirulent an insect model, confirming dependent on Our data also implicate scaffold transcriptional regulation of arginine metabolism but via different mechanism S. cerevisiae since dispensable for nitrogen sources. plays dominant virulence, IPK pathway has diverged pathogens.IMPORTANCEThe World Health Organization emphasized urgent need global action tackling high morbidity mortality rates stemming invasive infections, which exacerbated limited variety compromised effectiveness available drug classes. Fungal promising target new therapy, critical promoting albicans, impacts cell wall integrity. This contrasts current therapies, only single function. enzymes exert their effect through inositol products scaffold. Here, confirm promotes all traits attenuated deletion, reinforcing our ongoing efforts find effector proteins create inhibitors targeting site, antifungal class.

Язык: Английский

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