{"list":[{"mbpostId":"MPST000232","announcementDate":"2026\/11\/10","revision":1,"location":"MPST000232.1","createdAt":"2026\/11\/10","modifiedAt":"2026\/11\/10","fileCount":50,"title":"Untargeted metabolomics of Hermetia illucens mid-\/hind-gut: GH9-CBM3 transgenic vs wild-type under conventional and germ-free conditions","keywords":"Hermetia illucens, black soldier fly, GH9-CBM3, cellulase, transgenic, gut metabolomics, untargeted LC-MS, ESI, Orbitrap","description":"LC-MS\/MS untargeted metabolomics dataset from black soldier fly (Hermetia illucens) mid-\/hind-gut tissue. 24 biological samples (6 per group): wild-type conventional (WT_Con), wild-type germ-free (WT_GF), GH9-CBM3 transgenic conventional (GH9_Con), and GH9-CBM3 transgenic germ-free (GH9_GF). Data acquired on Thermo Q Exactive HF-X with C18 reversed-phase UHPLC in alternating positive\/negative ESI polarity. Raw .raw files provided for both polarities (48 files total).","pubmedId":"","publicationType":"doi","principalInvestigator":"Haixu Zhang","affiliation":"Shanghai Jiao Tong University, School of Environmental Science and Engineering","note":"","submitter":"Haixu Zhang"},{"mbpostId":"MPST000122","announcementDate":"2026\/10\/29","revision":0,"location":"MPST000122.0","createdAt":"2025\/10\/29","modifiedAt":"2025\/10\/29","fileCount":19,"title":"Optimization and creation of GC\/MS library using hydrogen gas as a mobile phase for metabolomics","keywords":"Hydrogen gas, Helium gas, GC\/MS, diffusion coeffecient, database","description":"The price of high-purity helium (He) gas is rising. Hydrogen (H\u2082) gas is being considered as an alternative mobile phase for GC\/MS. However, because the outlet of the capillary column in GC\/MS is evacuated, it is difficult to directly apply the separation conditions established for He gas to GC\/MS analysis. This is because H\u2082 gas has a lower viscosity and a higher diffusion coefficient than He gas. Furthermore, when coeluting, similar structure metabolites, such as sugars, are difficult to separate using only MS spectral deconvolution. Therefore, a high-resolution column is required. The column was replaced the I. D.  0.25 mm, 30 m length, poly (5% diphenyl-95% dimethyl) siloxane column for He with I. D. 0.18 mm, 30 m length, for H\u2082 gas with I.D. 0.18 mm, 30 m length, +5 m retention gap column. To match the phase ratio, the column was changed to the same stationary phase (0.18 \u03bcm film thickness) as the H2 gas column. Using this column, changes in retention index (RI), mass spectrum, and sensitivity difference were evaluated. A database containing over 590 compounds of interest for GC\/MS metabolomics was created and registered in MassBank.\n","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Hiromi Miyagawa","affiliation":"Osaka University","note":"","submitter":"Hitomi Yadori"},{"mbpostId":"MPST000120","announcementDate":"2026\/10\/27","revision":0,"location":"MPST000120.0","createdAt":"2025\/10\/27","modifiedAt":"2025\/10\/27","fileCount":42,"title":"Metabolomics-based investigation of compounds correlating sensory profiles of strawberry","keywords":"Strawberry; VOC metabolomics; Gas chromatography\/mass spectrometry; Orthogonal Partial-Least Squares Regression; Non-volatile compounds","description":"Metabolomics-based investigation of compounds correlating sensory profiles of strawberry\n","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Yuri Yoshiyama","affiliation":"University of Osaka","note":"","submitter":"Yuri Yoshiyama"},{"mbpostId":"MPST000091","announcementDate":"2026\/10\/24","revision":0,"location":"MPST000091.0","createdAt":"2025\/08\/19","modifiedAt":"2025\/08\/19","fileCount":22,"title":"Eubiotic gut microbiota mitigate colitis via colonic Treg expansion.","keywords":"ceruloplasmin; inflammatory bowel disease; regulatory T-cells; short-chain fatty acids; ulcerative colitis ","description":"Aberrant gut microbiota has been linked to a disrupted immune response, leading to intestinal pathological conditions. However, the causality and mechanisms have remained unclear. \nHere we used a wild-type mouse substrain resistant to dextran sulfate sodium (DSS)-induced colitis to understand the characteristics of the eubiotic microbiota and the mechanisms underlying colitis resistance. Colitis-resistant mice presented a significantly greater colonic Foxp3+ regulatory T (Treg) population after DSS challenge, while numbers of helper T1 and 17 cells were comparable. Cohousing experiments revealed that Treg expansion was induced by the gut microbiota of colitis-resistant mice, and mice with eubiotic microbiota maintained high concentrations of three microbial metabolites, SCFAs (acetate, butyrate, and propionate). Furthermore, proteomics revealed that iron binding and iron-metabolizing ceruloplasmin silencing were upregulated relating disease-resistance. Of note, iron is pivotal in SCFA-producing bacteria. Taken together, our results reveal that silencing ceruloplasmin expression restricts iron metabolism, thereby increasing SCFA production. The eubiotic gut microbiota and combinations of SCFAs contribute to Treg induction, which helps control colitis progression. \n","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Nobuyuki Okahashi","affiliation":"The University of Osaka","note":"","submitter":"Nobuyuki Okahashi"},{"mbpostId":"MPST000171","announcementDate":"2026\/10\/24","revision":0,"location":"MPST000171.0","createdAt":"2026\/03\/02","modifiedAt":"2026\/03\/02","fileCount":48,"title":"Eubiotic gut microbiota mitigate colitis via colonic Treg expansion.","keywords":"ceruloplasmin; inflammatory bowel disease; regulatory T-cells; short-chain fatty acids; ulcerative colitis ","description":"Aberrant gut microbiota has been linked to a disrupted immune response, leading to intestinal pathological conditions. However, the causality and mechanisms have remained unclear. \nHere we used a wild-type mouse substrain resistant to dextran sulfate sodium (DSS)-induced colitis to understand the characteristics of the eubiotic microbiota and the mechanisms underlying colitis resistance. Colitis-resistant mice presented a significantly greater colonic Foxp3+ regulatory T (Treg) population after DSS challenge, while numbers of helper T1 and 17 cells were comparable. Cohousing experiments revealed that Treg expansion was induced by the gut microbiota of colitis-resistant mice, and mice with eubiotic microbiota maintained high concentrations of three microbial metabolites, SCFAs (acetate, butyrate, and propionate). Furthermore, proteomics revealed that iron binding and iron-metabolizing ceruloplasmin silencing were upregulated relating disease-resistance. Of note, iron is pivotal in SCFA-producing bacteria. Taken together, our results reveal that silencing ceruloplasmin expression restricts iron metabolism, thereby increasing SCFA production. The eubiotic gut microbiota and combinations of SCFAs contribute to Treg induction, which helps control colitis progression. \n","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Nobuyuki Okahashi","affiliation":"The University of Osaka","note":"","submitter":"Nobuyuki Okahashi"},{"mbpostId":"MPST000184","announcementDate":"2026\/10\/15","revision":1,"location":"MPST000184.1","createdAt":"2026\/10\/13","modifiedAt":"2026\/10\/13","fileCount":22,"title":"Lysophospholipase PNPLA7 is a critical checkpoint of phosphatidylcholine catabolism and turnover for skeletal muscle homeostasis","keywords":"Lysophospholipase, Phospholipid, Phosphatidylcholine, Skeletal muscle, Mitochondria, Choline","description":"Current evidence suggests that disturbed phosphatidylcholine (PC) turnover causes skeletal muscle dysfunction. However, the enzyme that converts lysophosphatidylcholine (LPC) to glycerophosphocholine (GPC), an irreversible checkpoint in PC catabolism, in skeletal muscle has remained unidentified. Here we show that PNPLA7, a patatin-like phospholipase isoform, is responsible for this process. Pnpla7 deletion in myoblasts impeded the conversion of LPC to GPC and then to choline. Quadriceps muscles in global Pnpla7-deficient mice displayed thinner muscle fibers with aberrant mitochondrial morphology, reduced endurance capacity, and decreased expression of genes for fatty acid \u03b2-oxidation, mitochondrial functions, and slow-twitch fibers with age. These abnormalities were preceded by alteration in phospholipid composition with decreases of docosahexaenoic acid-containing PC and mitochondrial cardiolipin. Moreover, skeletal muscle-specific Pnpla7 deficiency resulted in muscle phenotypes similar to its global deficiency. Identification of the lysophospholipase PNPLA7 aids further understanding of the role of PC turnover in skeletal muscle homeostasis.","pubmedId":"42815479","publicationType":"pubmed","principalInvestigator":"Makoto Murakami","affiliation":"The University of Tokyo","note":"","submitter":"Kaori Igarashi"},{"mbpostId":"MPST000115","announcementDate":"2026\/10\/08","revision":0,"location":"MPST000115.0","createdAt":"2025\/10\/08","modifiedAt":"2025\/10\/08","fileCount":64,"title":"Non-destructive prediction of banana ripeness (color, sugar content) using GC-MS-based VOC profiling and OPLS regression models","keywords":"Banana; Gas chromatography\/mass spectrometry; Orthogonal Partial-Least Squares Regression; VOC metabolomics; Non-destructive ripening prediction","description":"Bananas are a fruit that is produced and exported in large quantities around the world. Bananas are a climacteric fruit that continues to ripen even after harvesting. Bananas are imported to Japan in a green state and transported to Japan in low-oxygen and low-temperature (13 \u2103) containers to artificially stop the ripening process. Upon arrival in Japan, they are treated with ethylene to restart the ripening process. It is important to monitor banana quality in situations where artificial ripening takes place. Important processes associated with banana ripening include fruit softening and skin colour changes, total soluble solids (TSS) concentration and the formation of volatile compounds. The alteration of total volatile matter production in banana fruit during storage is closely related to fruit ripening and ripening-related parameters such as firmness, colour, soluble solids SSC; soluble sugar content. Because the VOCs produced by bananas are the result of biological reactions occurring in the peel and pulp, measuring VOCs emitted from bananas may allow non-destructive prediction of the condition of bananas.","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Sayaka Togami","affiliation":"The University of Osaka","note":"","submitter":"Sayaka Togami"},{"mbpostId":"MPST000113","announcementDate":"2026\/10\/08","revision":0,"location":"MPST000113.0","createdAt":"2025\/10\/08","modifiedAt":"2025\/10\/08","fileCount":45,"title":"Prediction of Fermentation Indicators in Beer Brewing Using Exhaust Gas VOC profiles","keywords":"Beer Fermentation; VOC metabolomics; Gas chromatography\/mass spectrometry; High Performance Liquid Chromatography; Gas chromatography\/ Flame Ionization Detector; Orthogonal Partial-Least Squares Regression","description":"Prediction of Fermentation Indicators in Beer Brewing Using Exhaust Gas VOC profiles","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Keisuke Yamauchi","affiliation":"Osaka University","note":"","submitter":"Keisuke Yamauchi"},{"mbpostId":"MPST000222","announcementDate":"2026\/09\/25","revision":0,"location":"MPST000222.0","createdAt":"2026\/09\/24","modifiedAt":"2026\/09\/24","fileCount":171,"title":"Microbiota maturation prevents Clostridium botulinum colonization through metabolic niche competition","keywords":" infant botulism; Clostridium botulinum; gut microbiota; colonization resistance; Stickland metabolism; Clostridioides difficile; nutrient competition","description":"Infant botulism reflects a striking age dependence in susceptibility to intestinal colonization byClostridium botulinum, whereas healthy adults are generally resistant. Maturation of the gut microbiotais thought to drive the acquisition of colonization resistance, but its basis remains unknown. Here, wefunctionally compared longitudinally collected human infant microbiotas in germ-free mice, revealinga transition from susceptibility to resistance and nutrient competition by specific amino acid-metabolizing bacteria as a resistance mechanism. Intestinal metabolomics identified 5-aminovalerateas a hallmark of resistant microbiotas, implicating Stickland metabolism, an amino acid metabolicpathway used by certain Clostridia and also by C. botulinum. Resistant microbiotas were enriched inStickland-metabolizing Clostridia, including Clostridioides difficile. C. botulinum and C. difficileshowed overlapping amino acid utilization, and C. difficile restricted C. botulinum expansion throughamino acid competition. Together, these findings demonstrate that acquisition of Stickland-metabolizing Clostridia during infancy prevents C. botulinum colonization through competition forshared amino-acid-dependent nutritional niches.","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Nobuhide Kobayashi","affiliation":"Department of Bacteriology, Graduate School of Medical Sciences, Kanazawa University","note":"","submitter":"fukushin"},{"mbpostId":"MPST000218","announcementDate":"2026\/09\/15","revision":0,"location":"MPST000218.0","createdAt":"2026\/09\/15","modifiedAt":"2026\/09\/15","fileCount":67,"title":"Droplet microfluidic iX-seq reveals a growth-supportive interaction between Phascolarctobacterium faecium and Eubacterium limosum in the human gut microbiota","keywords":"droplet microfluidics, gut microbiota, cross-feeding, Phascolarctobacterium faecium, Eubacterium limosum, 2-oxoglutarate, succinate metabolism","description":"Background: The human gut microbiota comprises hundreds of bacterial species that form a dynamic metabolic network, in which the exchange of microbial metabolites, known as cross-feeding, is integral to community function and host health.  However, defining and isolating specific cross-feeding interactions remains challenging due to the limitations of conventional culture-based approaches.  Droplet microfluidics enables high-throughput screening and isolation of bacteria from complex communities by encapsulating cells in water-in-oil droplets, allowing for parallel cultivation of thousands of stochastically contained microcultures.  In this study, we developed a droplet microfluidics-based screening platform integrated with 16S rRNA gene amplicon sequencing, collectively termed iX-seq, to identify novel cross-feeding interactions directly from a human fecal sample.\nResults: Using iX-seq, we identified an interaction in which the growth of P. faecium was supported by E. limosum in droplet co-cultures.  The growth of P. faecium was modestly affected when co-cultured in vitro but notably required E. limosum co-inoculation for intestinal colonization in germ-free mice.  Metabolomic profiling implicated metabolites of P. faecium\u2019s succinate metabolic pathway in this interaction, with 2-oxoglutarate (2-OG) being the most strongly differentiating metabolite between E. limosum-inoculated and control mouse feces.  Supplementation of 2-OG in monoculture increased P. faecium growth in a concentration-dependent manner, consistent with a growth-supportive role.  \nConclusions: Our results reveal a previously unrecognized growth-supportive interaction between P. faecium and E. limosum, for which cross-feeding of succinate-pathway metabolites, such as 2-OG, is a candidate mechanism, offering new insight into gut microbial metabolic dependencies.  By enabling scalable, culture-based screening directly from fecal samples, the iX-seq approach demonstrates a framework for studying cross-feeding interactions within the gut microbiota and represents a practical new approach to investigating complex microbial communities.","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Kazuki Tanaka","affiliation":"Institute for Advanced Biosciences, Keio University","note":"","submitter":"fukushin"},{"mbpostId":"MPST000160","announcementDate":"2026\/09\/09","revision":1,"location":"MPST000160.1","createdAt":"2026\/06\/06","modifiedAt":"2026\/06\/06","fileCount":528,"title":"Evaluation of sterol selectivity of sulfotransferase orthologs","keywords":"Untargeted lipidomics","description":"Metabolic experiments with purified sulfotransferases derived from Bacteroides thetaiotaomicron, mouse, and human. Samples were supplemented with 50 \u03bcM sterol standards and 100 \u03bcM PAPS standards.\nPAPS 3\u2032-Phosphoadenosine-5\u2032-phosphosulfate triethylammonium salt\u3000Sigma-Aldrich\u300094455)\nSitosterol sulfate (trimethylamine) \tMedChemExpress\tHY-N10478A\n\u03b2-Sitosterol, synthetic, \u226595%\tSigma-Aldrich\tS1270-25MG\nBrassicasterol\tTAMA BIOCHEMICAL \t306-02871\nCampesterol\tTAMA BIOCHEMICAL \t306-01391\nStigmasterol\tTAMA BIOCHEMICAL \t302-01413\nCholesterol\tSigma-Aldrich\tC8667-5G\nCoprostanol\tSigma-Aldrich\tC7578-50MG","pubmedId":"10.1016\/j.isci.2026.117883","publicationType":"doi","principalInvestigator":"Koki Tomita","affiliation":"Keio university","note":"","submitter":"Koki Tomita"},{"mbpostId":"MPST000145","announcementDate":"2026\/09\/09","revision":0,"location":"MPST000145.0","createdAt":"2025\/12\/25","modifiedAt":"2025\/12\/25","fileCount":163,"title":"Untargeted lipidomics of Bacteroides thetaiotaomicron supplemented with six types of sterol standards","keywords":"Untargeted lipidomics","description":"B. thetaiotaomicron was cultured with 10 \u03bcM of cholesterol, sitosterol, campesterol, stigmasterol, brassicasterol, coprostanol.","pubmedId":"10.1016\/j.isci.2026.117883","publicationType":"doi","principalInvestigator":"Koki Tomita","affiliation":"Keio University","note":"","submitter":"Koki Tomita"},{"mbpostId":"MPST000144","announcementDate":"2026\/09\/09","revision":0,"location":"MPST000144.0","createdAt":"2025\/12\/25","modifiedAt":"2025\/12\/25","fileCount":23,"title":"Spike samples of SIS standard and Bacteroides thetaiotaomicron","keywords":"Untargeted lipidomics","description":"SIS standard: 250nM\n2x diluted B. thetaiotaomicron extract \nMixture of:\n- SIS standard: 500nM\n- Lipid extract of B. thetaiotaomicron with sitosterol addition","pubmedId":"10.1016\/j.isci.2026.117883","publicationType":"doi","principalInvestigator":"Koki Tomita","affiliation":"Keio University","note":"","submitter":"Koki Tomita"},{"mbpostId":"MPST000143","announcementDate":"2026\/09\/09","revision":0,"location":"MPST000143.0","createdAt":"2025\/12\/25","modifiedAt":"2025\/12\/25","fileCount":330,"title":"Untargeted lipidomics of an E. coli lysate expressing bacterial sulfotransferase","keywords":"Untargeted lipidomics","description":"Add 50 \u03bcM of sitosterol and 100 \u03bcM of 3'-phosphoadenosine 5'-phosphate to 100 ng of E. coli lysate. After four hours' incubation, the samples were frozen at -80 \u00b0C.","pubmedId":"10.1016\/j.isci.2026.117883","publicationType":"doi","principalInvestigator":"Koki Tomita","affiliation":"Keio University","note":"","submitter":"Koki Tomita"},{"mbpostId":"MPST000142","announcementDate":"2026\/09\/09","revision":0,"location":"MPST000142.0","createdAt":"2025\/12\/25","modifiedAt":"2025\/12\/25","fileCount":457,"title":"Untargeted lipidomics of cholesterol and sitosterol in six species of the phylum Bacteroidota","keywords":"Untargeted lipidomics","description":"Alistipes finegoldii, Porphyromonas gingivalis, Parabacteroides goldsteinii, Parabacteroides johnsonii, Barnesiella intestinihominis, Prevotella denticola, Bacteroides uniformis, Bacteroides fragilis, Bacteroides caccae, and Bacteroides thetaiotaomicron","pubmedId":"10.1016\/j.isci.2026.117883","publicationType":"doi","principalInvestigator":"Koki Tomita","affiliation":"Keio University","note":"","submitter":"Koki Tomita"},{"mbpostId":"MPST000213","announcementDate":"2026\/08\/23","revision":0,"location":"MPST000213.0","createdAt":"2026\/08\/23","modifiedAt":"2026\/08\/23","fileCount":7,"title":"DART\u2013TOF MS Spectral Fingerprint Dataset of Rubroshorea leprosula","keywords":"Rubroshorea leprosula, DART\u2013TOF MS, Wood Identification, Geographical Origin","description":"This dataset contains raw data from DART\u2013TOF MS spectral fingerprint of Rubroshorea leprosula wood samples collected from West, Central, and East Borneo, Indonesia.  Raw data is a project type in msAxel@LP. These data can be reused for comparative wood chemical profiling, development of alternative preprocessing and chemometric workflows, and expansion of reference datasets for timber traceability and geographical origin research.","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Rudi Heryanto","affiliation":"IPB University","note":"","submitter":"Rudi Heryanto"},{"mbpostId":"MPST000092","announcementDate":"2026\/08\/19","revision":0,"location":"MPST000092.0","createdAt":"2025\/08\/19","modifiedAt":"2025\/08\/19","fileCount":18,"title":"13C metabolic flux analysis of arginine metabolism","keywords":"13C metabolic flux anlaysis, macrophage","description":"[Introduction]\n13C-metabolic flux analysis is a powerful tool for qualifying intracellular metabolic flow. However, the applicable range of this method is limited for central carbon metabolism. Mammalian cells, especially immune cells, use arginine metabolism to biosynthesize nitric oxide (NO) and polyamine via induced nitric oxide synthetase (iNOS) and arginase-1 (Arg-1), respectively, to drive and support their immune functions. In this study, 13C-metabolic flux analysis for arginine metabolism was developed and applied to resting (M0), pro (M1)- and anti (M2)-inflammatory macrophage-like cells.\n[Methods and materials]\nHuman leukemia THP-1 cells were cultured with [U-13C]arginine for 24 h. THP-1 cells were differentiated into M0-like macrophage with 200 nM phorbol 12-myristate 13-acetate for 48 h. After 3 days of rest, the cells were polarized into M1- and M2-like macrophages by addition of 1 \u00b5g\/mL E. coli lipopolysaccharide and 20 ng\/mL TNF-\u03b1 for 24 h, and interleukin-4 and -13 for 48 h, respectively. Metabolic flux distributions were calculated by influx\/efflux of extracellular metabolites and 13C-labeling ratio of intracellular metabolites measured by HPLC and LC-QTOF\/MS, respectively. \n[Results] \n[U-13C]arginine is catabolized to M+6 citrulline via iNOS and M+5 citrulline via Arg-1, indicating that 13C-labeling pattern of citrulline has the information of the flux branch ratio between iNOS and Arg-1 reactions. M+6 fraction of citrulline in M0-like THP-1 cells was over 90%, while M+5 citrulline fraction was less than 4%, suggesting that iNOS reaction was dominant against Arg-1 reaction. To investigate the material balance of arginine metabolism, time courses of cell number and concentration of medium components were observed. Arginine was taken up by 84 nmol\/106 cells\/h, and ornithine and citrulline were secreted by 44 and 14 nmol\/106 cells\/h, respectively. The flux distribution of arginine metabolism in M0-like THP-1 cells showed that 79% of the incorporated arginine was catabolized via Arg-1 reaction and the rest was metabolized via iNOS reaction. 13C-metabolic flux analysis was further applied to M1- and M2-like THP-1 cells. The levels of iNOS and Arg-1 flux of M1-like THP-1 cells were 2.5- and 2.3-fold larger than those of M2-like THP-1 cells, suggesting that M1 macrophages activated arginine metabolism more than M2 macrophages. \n","pubmedId":"","publicationType":"pubmed","principalInvestigator":"Takeo Taniguchi","affiliation":"The university of Osaka","note":"","submitter":"Takeo Taniguchi"},{"mbpostId":"MPST000197","announcementDate":"2026\/07\/27","revision":0,"location":"MPST000197.0","createdAt":"2026\/05\/27","modifiedAt":"2026\/05\/27","fileCount":110,"title":"Hypertensive Stress\u2013Induced Rewiring of Cardiac Macrophage-Derived Intercellular Signaling Underlies Metabolic Remodeling and Inflammation in Non-Obese HFpEF","keywords":"Lipidomics, Metabolomics, HFpEF","description":"Heart failure with preserved ejection fraction (HFpEF) is a leading cause of morbidity and mortality worldwide, although effective therapies remain limited.","pubmedId":"","publicationType":"pubmed","principalInvestigator":"KAZUTAKA IKEDA","affiliation":"Kazusa DNA Research Institute","note":"","submitter":"KAZUTAKA IKEDA"},{"mbpostId":"MPST000192","announcementDate":"2026\/07\/15","revision":0,"location":"MPST000192.0","createdAt":"2026\/05\/14","modifiedAt":"2026\/05\/19","fileCount":338,"title":"High-throughput monitoring of in vitro enzymatic reactions using probe electrospray ionization-mass spectrometry","keywords":"Probe electrospray ionization, PESI-MS, In vitro enzyme reaction, non-oxidative glycolysis","description":"Probe electrospray ionization-mass spectrometry (PESI-MS) is an ambient ionization technique that enables rapid and simple mass spectrometry with minimal sample preparation. In this study, we evaluated the applicability of PESI-MS for the quantitative analysis of metabolites in in vitro enzyme reaction mixtures, which often contain high concentrations of proteins, salts, and buffers that are not suitable for conventional MS. Using glycolytic metabolites as a model, we optimized the type of mixing organic solvents, data processing method, and investigated the effects of additives and reaction components on ionization efficiency and signal stability. Ethanol and 2-propanol were identified as suitable solvents for the detection of sugar phosphates, organic acids, and nucleotides. The quantitative reproducibility was improved by employing a total peak-height-based data processing method. The presence of proteins had a minimal influence on ionization. Although high concentrations of MgCl2 and buffers suppressed the signal intensity, metabolite signals were still observable at 10 and 50 mM, respectively. The linearity of the calibration curves and the reproducibility of the analysis of glycolytic metabolites in the mock enzyme reaction solution were confirmed. Finally, PESI-MS was successfully used to monitor the time course of intermediates in an in vitro synthetic non-oxidative glycolysis system. The data trend obtained by PESI-MS was roughly consistent with the results of conventional LC-MS analysis. These findings demonstrate that PESI-MS is a simple, rapid, and robust method for analyzing in vitro enzymatic reactions.","pubmedId":"10.1007\/s00216-026-06656-2","publicationType":"doi","principalInvestigator":"Nobuyuki Okahashi","affiliation":"The University of Osaka","note":"","submitter":"Nobuyuki Okahashi"},{"mbpostId":"MPST000118","announcementDate":"2026\/07\/12","revision":0,"location":"MPST000118.0","createdAt":"2025\/10\/21","modifiedAt":"2025\/10\/21","fileCount":54,"title":"Metabolomic changes in the pancreas during the pancreatic cancer progression in a genetically-engineered mouse model of Kras mutation with knockout of Tgfbr2 (Glucose)","keywords":"pancreatic cancer, genetically-engineered mouse, Kras, Tgfbr2, cachexia","description":"Pancreatic ductal adenocarcinoma (PDAC) is a poor prognostic cancer and the detailed metabolic alteration is still poorly understood. We investigated the metabolic alteration in mice with PDAC by capillary electrophoresis-mass spectrometry (CE-MS) and mass spectrometry imaging (MSI). o-Acetylcarnitine, a metabolite of carnitine, and acetyl-CoA increased during cancer progression  in a PDAC mouse model by CE-MS, while MSI revealed that o-acetylcarnitine was mainly localized in PDAC cells. Immunohistochemistry showed overexpression of \u03b3-butyrobetaine 2-oxoglutarate dioxygenase 1 (BBOX1), which synthesizes carnitine from \u03b3-butyrobetaine, also mainly in PDAC cells. Meldonium, an inhibitor of BBOX1, inhibited PDAC proliferation and cytokine secretion, thereby prolonging the survival of PDAC-bearing mice. In patients with PDAC resection, BBOX1 expression was determined as an independent poor prognostic factor for overall survival. Therefore, these results suggest that blocking L-carnitine synthesis would improve the prognosis of patients with PDAC.","pubmedId":"42602712","publicationType":"pubmed","principalInvestigator":"Hideaki Ijichi","affiliation":"Clinical Nutrition Center, Graduate School of Medicine, the University of Tokyo","note":"","submitter":"Ryosuke Hayasaka"}],"meta":{"total":119,"from":1,"to":20}}