Capillary Electrophoresis Mass Spectrometry for Inositol (Pyro)phosphate Profiling.

The turnover of myo-inositol phosphates (InsPs) and myo-inositol pyrophosphates (PP-InsPs) is a dynamic process that plays an important role in many physiological processes by transmitting signals within cellular pathways and networks. Profiling the InsPs and PP-InsPs isomers and quantifying their change in abundance is a significant challenge for several reasons. First, InsPs and PP-InsPs constitute a diverse metabolite pool, characterized by the complexity as a result of the numerous possible isobaric isomers.

Oncometabolite 5-IP inhibits inositol 5-phosphatase to license E-cadherin endocytosis.

E-cadherin downregulation is an epithelial-mesenchymal transition hallmark canonically attributed to transcriptional repression. Here we delineate a metabolite-driven endocytic route of E-cadherin downregulation in inflammation-associated colorectal cancer (CRC). Specifically, IP kinase-2 (IP6K2), a 5-diphosphoinositol pentakisphosphate (5-IP) synthase upregulated in patients with CRC, is activated via a ROS-Src phosphorylation axis elicited by dextran sulfate sodium (DSS), generating 5-IP around adherens junction (AJ) to promote E-cadherin endocytosis and the transcriptional activities of β-catenin.

Expanding the Inositol Pyrophosphate Toolbox: Stereoselective Synthesis and Application of PP-InsP Isomers in Plant Signaling.

Inositol pyrophosphates (PP-InsPs) are highly phosphorylated signaling molecules that regulate diverse cellular processes, including phosphate homeostasis and energy metabolism across species. Despite extensive research on well-characterized exhaustively phosphorylated PP-InsPs, such as 5-PP-InsP (5-InsP) and 1,5-(PP)-InsP (1,5-InsP), the functional relevance of less abundant not fully phosphorylated isomers, remains largely unknown. In this study, we synthesized all unsymmetric 5-PP-InsP isomers in enantiopure form and assigned their structures using P-NMR analysis in combination with a chiral solvating agent.

Stereoselective chemoenzymatic phytate transformations provide access to diverse inositol phosphate derivatives.

Phosphorylated -inositols (InsPs) are essential cytoplasmic signaling molecules, while their lipidated analogs (PtdInsPs) play a crucial role in membrane signaling. Stereoselective synthesis of these compounds has been achieved through various methods, predominantly using the compound -inositol as a starting material. However, phytate (InsP), also a compound, is the most abundant inositol derivative in plants - far more prevalent than -inositol itself.

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

Inositol phosphates control many central processes in eukaryotic cells including nutrient availability, growth, and motility. Kinetic resolution of a key modulator of their signaling functions, the turnover of the phosphate groups on the inositol ring, has been hampered by slow uptake, high dilution, and constraining growth conditions in radioactive pulse-labeling approaches. Here, we demonstrate a rapid (seconds to minutes) and nonradioactive labeling strategy of inositol polyphosphates through O-water in yeast, human cells, and amoeba, which can be applied in any media.

Basic features of cellular inositol metabolism as revealed by a newly developed LC-MS method.

Inositol plays key roles in many cellular processes. Several studies focussed on the quantitative analysis of phosphorylated forms of inositol, enabled by analytical tools developed to detect these highly charged molecules. Direct measurement of free inositol however has been challenging, because the molecule is uncharged and polar.

Synthesis of a New Purine Analogue Class with Antifungal Activity and Improved Potency against Fungal IPK.

New antifungals are urgently needed to treat deadly fungal infections. Targeting the fungal inositol polyphosphate kinases IPK (Arg1) and IPK (Kcs1) is a promising strategy as it has been validated genetically to be crucial for fungal virulence but never pharmacologically. We now report the synthesis of , an analogue of 2-(-trifluorobenzylamino)-6-(-nitrobenzylamino)purine (), and demonstrate that it more potently inhibits recombinant Arg1 from the priority pathogen () (IC = 0.

Breathomics for diagnosing tuberculosis in diabetes mellitus patients.

Introduction: Individuals with diabetes mellitus (DM) are at an increased risk of (Mtb) infection and progressing from latent tuberculosis (TB) infection to active tuberculosis disease. TB in the DM population is more likely to go undiagnosed due to smear-negative results.

Methods: Exhaled breath samples were collected and analyzed using high-pressure photon ionization time-of-flight mass spectrometry.

Orchestration of phosphate homeostasis by the ITPK1-type inositol phosphate kinase in the liverwort Marchantia polymorpha.

Land plants have evolved sophisticated sensing mechanisms and signaling pathways to adapt to phosphate-limited environments. While molecular players contributing to these adaptations in flowering plants have been described, how nonvascular bryophytes regulate phosphate (Pi) homeostasis remained largely unknown. In this study, we present findings that both male and female plants of the liverwort Marchantia polymorpha respond to altered phosphate availability through substantial developmental changes.

Variations in Quinolinic Acid Levels in Tuberculosis Patients with Diabetes Comorbidity: A Pilot Prospective Cohort Study.

Objective: We aimed to investigate dysregulated metabolic pathways and identify diagnostic and therapeutic targets in patients with tuberculosis-diabetes (TB-DM).

Methods: In our prospective cohort study, plasma samples were collected from healthy individuals, diabetic (DM) patients, untreated TB-only (TB-0)/TB-DM patients (TB-DM-0), and cured TB (TB-6)/TB-DM patients (TB-DM-6) to measure the levels of amino acids, fatty acids, and other metabolites in plasma using high-throughput targeted quantification methods.

Results: Significantly different biological processes and biomarkers were identified in DM, TB-DM-0, and TB-DM-6 patients.

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

Dietary intake of phytate has various reported health benefits. Previous work showed that the gut microbiota can convert phytate to short-chain fatty acids (SCFAs), but the microbial species and metabolic pathway are unclear. Here we identified Mitsuokella jalaludinii as an efficient phytate degrader, which works synergistically with Anaerostipes rhamnosivorans to produce the SCFA propionate.

Inositol pyrophosphate dynamics reveals control of the yeast phosphate starvation program through 1,5-IP and the SPX domain of Pho81.

Eukaryotic cells control inorganic phosphate to balance its role as essential macronutrient with its negative bioenergetic impact on reactions liberating phosphate. Phosphate homeostasis depends on the conserved INPHORS signaling pathway that utilizes inositol pyrophosphates and SPX receptor domains. Since cells synthesize various inositol pyrophosphates and SPX domains bind them promiscuously, it is unclear whether a specific inositol pyrophosphate regulates SPX domains in vivo, or whether multiple inositol pyrophosphates act as a pool.

β-lapachone regulates mammalian inositol pyrophosphate levels in an NQO1- and oxygen-dependent manner.

Inositol pyrophosphates (PP-InsPs) are energetic signaling molecules with important functions in mammals. As their biosynthesis depends on ATP concentration, PP-InsPs are tightly connected to cellular energy homeostasis. Consequently, an increasing number of studies involve PP-InsPs in metabolic disorders, such as type 2 diabetes, aspects of tumorigenesis, and hyperphosphatemia.

Comprehensive Profiling of Rapamycin Interacting Proteins with Multiple Mass Spectrometry-Based Omics Techniques.

Profiling drug-protein interactions is critical for understanding a drug's mechanism of action and predicting the possible adverse side effects. However, to comprehensively profile drug-protein interactions remains a challenge. To address this issue, we proposed a strategy that integrates multiple mass spectrometry-based omics analysis to provided global drug-protein interactions, including physical interactions and functional interactions, with rapamycin (Rap) as a model.

The phytase RipBL1 enables the assignment of a specific inositol phosphate isomer as a structural component of human kidney stones.

Inositol phosphates (InsPs) are ubiquitous in all eukaryotes. However, since there are 63 possible different phosphate ester isomers, the analysis of InsPs is challenging. In particular, InsP, InsP and InsP already amass 41 different isomers, of which some occur as enantiomers.

Determination of 5-methyldeoxycytosine and oxidized derivatives by nano-liquid chromatography with zwitterionic monolithic capillary column.

DNA methylation is one of the epigenetic modifications at the 5-carbon of cytosine to form 5-methyl-2'-deoxycytidine (5mdC). In mammalian cells, 5mdC can be transferred to 5-hydroxymethyl-2'-deoxycytidine (5hmdC) by ten-eleven translocation (TET), and 5hmdC is further oxidized to 5-formyl-2'-deoxycytidine (5fodC) and 5-carboxyl-2'-deoxycytidine (5cadC). In the present work, we developed a highly sensitive nano liquid chromatographic method for the determination of 5mC and 5hmC with zwitterionic monolithic capillary column.

Capillary electrophoresis mass spectrometry identifies new isomers of inositol pyrophosphates in mammalian tissues.

Technical challenges have to date prevented a complete profiling of the levels of -inositol phosphates (InsPs) and pyrophosphates (PP-InsPs) in mammalian tissues. Here, we have deployed capillary electrophoresis mass spectrometry to identify and record the levels of InsPs and PP-InsPs in several tissues obtained from wild type mice and a newly created PPIP5K2 knockout strain. We observe that the mouse colon harbours unusually high levels of InsPs and PP-InsPs.

Stable Isotopomers of Inositol Uncover a Complex MINPP1-Dependent Inositol Phosphate Network.

The water-soluble inositol phosphates (InsPs) represent a functionally diverse group of small-molecule messengers involved in a myriad of cellular processes. Despite their centrality, our understanding of human InsP metabolism is incomplete because the available analytical toolset to characterize and quantify InsPs in complex samples is limited. Here, we have synthesized and applied symmetrically and unsymmetrically C-labeled -inositol and inositol phosphates.

Profiling protein interactions by purification with capillary monolithic affinity column in combination with label-free quantitative proteomics.

An approach for profiling protein-protein interactions by using affinity purification with capillary monolithic immobilized metal affinity chromatography column (cm-IMAC) in combination with label free quantitative proteomics was described in the present work. The cm-IMAC columns were prepared in a single step by copolymerization of the function monomer, namely (S)-2,2'-((1-carboxy-5-(pent‑4-enamido)pentyl)azanediyl)diacetic acid which provide a nitrilotriacetate (NTA) moiety to form chelated complexation with Ni (II) ions, inside the fused silica capillaries. The His-tagged bait protein can be easily immobilized on the cm-IMAC columns through the formation of chelating complexation with the NTA-Ni (II) functional groups of the matrix.

PFA-DSP-Type Phosphohydrolases Target Specific Inositol Pyrophosphate Messengers.

Inositol pyrophosphates are signaling molecules containing at least one phosphoanhydride bond that regulate a wide range of cellular processes in eukaryotes. With a cyclic array of phosphate esters and diphosphate groups around -inositol, these molecular messengers possess the highest charge density found in nature. Recent work deciphering inositol pyrophosphate biosynthesis in revealed important functions of these messengers in nutrient sensing, hormone signaling, and plant immunity.

[Effect of elevated atmospheric CO concentration and temperature on volatile halogenated organic compound content in soils of and seedlings].

Global changes caused by the increases of atmospheric CO concentration and temperature have important effects on soil biogeochemical processes. The synthesis and release of volatile halogenated organic compounds (VOXs) is an important pathway for soil to participate in the global material cycle and energy flow. In this study, and seedlings in the southern subtropics were selected as the research objects.

[Preparation of luminescent silica nanoparticles with immobilized metal ion affinity for labeling phosphorylated proteins in Western Blot].

Protein phosphorylation is an important type of post-translational protein modification. In Western Blot experiment, the assay of phosphoproteins need special phospho antibodies, which are expensive, difficult to preserve, poorly reproducible. To this end, the immobilized metal ion affinity luminescent silica nanoparticles for instead of phospho antibodies were prepared.

Curcumin Reduces Neuroinflammation and Improves the Impairments of Anesthetics on Learning and Memory by Regulating the Expression of miR-181a-5p.

Objective: The purpose of this study was to explore the role of curcumin (Cur) in isoflurane (ISO)-induced learning and memory dysfunction in Sprague-Dawley rats and further elucidate the mechanism of the protective effect produced by Cur.

Methods: Rat models of cognitive impairment were established by inhaling 3% ISO. The Morris water maze test was used to assess the cognitive function of rats.