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There is increasing industrial demand for five-carbon platform chemicals, particularly glutaric acid, a widely used building block chemical for the synthesis of polyesters and polyamides. Here we report the development of an efficient glutaric acid microbial producer by systems metabolic engineering of an L-lysine-overproducing Corynebacterium glutamicum BE strain. Based on our previous study, an optimal synthetic metabolic pathway comprising Pseudomonas putida L-lysine monooxygenase (davB) and 5-aminovaleramide amidohydrolase (davA) genes and C. glutamicum 4-aminobutyrate aminotransferase (gabT) and succinate-semialdehyde dehydrogenase (gabD) genes, was introduced into the C. glutamicum BE strain. Through system-wide analyses including genome-scale metabolic simulation, comparative transcriptome analysis, and flux response analysis, 11 target genes to be manipulated were identified and expressed at desired levels to increase the supply of direct precursor L-lysine and reduce precursor loss. A glutaric acid exporter encoded by ynfM was discovered and overexpressed to further enhance glutaric acid production. Fermentation conditions, including oxygen transfer rate, batch-phase glucose level, and nutrient feeding strategy, were optimized for the efficient production of glutaric acid. Fed-batch culture of the final engineered strain produced 105.3 g/L of glutaric acid in 69 h without any byproduct. The strategies of metabolic engineering and fermentation optimization described here will be useful for developing engineered microorganisms for the high-level bio-based production of other chemicals of interest to industry. [ABSTRACT FROM AUTHOR]

1,2-O-dilauryl-rac-glycero glutaric acid-(6′-methylresorufin) ester (DGGR) lipase activity has been proposed as a faster and less expensive test used in the diagnosis of acute pancreatitis (AP) compared to canine pancreatic lipase immunoreactivity (cPLI), which is considered the most sensitive and specific serum test available for dogs. Elevations in lipase activity have been observed in dogs with naturally occurring hypercortisolism (HC) and in those treated with exogenous steroids, which complicates the diagnosis of AP in dogs with HC. We compared lipase activity measured by DGGR and 1,2-diglyceride (1,2-DiG) assays in 22 dogs with HC, 22 with AP, and 22 healthy dogs. The dogs with HC had no clinical signs or ultrasonographic findings consistent with AP. DGGR lipase activity was elevated in 64% and 73% of the dogs with HC and AP, respectively, and in 18% of healthy dogs. 1,2-DiG lipase activity was high in 23% and 36% of the dogs with HC and AP, respectively, and in 5% of the healthy dogs. Both DGGR and 1,2-DiG lipase activities were significantly different between the healthy dogs and the other 2 groups, whereas no differences were detected between the dogs with HC and those with AP. Our results support a lack of specificity for both DGGR and 1,2-DiG lipase activity assays in aiding the diagnosis of AP in dogs with HC. [ABSTRACT FROM AUTHOR]

Schematic illustation of the selectivity adsorption mechanism of adsorbent. • We prepare glutaric acid modified Pb2+ imprinted chitosan-based composite membrane. • We study the adsorption behavior of the to Pb(II) in aqueous solution. • A good adsorption selectivity to Pb2+ In the presence of Cu(Ⅱ), Co(Ⅱ), Ni(Ⅱ) etc. • A better approach to increase Pb2+ adsorption ability by modified and Pb2+imprinted. Via heat of hydration, Pb(II) imprinted membrane composite adsorbent was prepared using glutaric acid as modifier, Pb(II) as imprinted ion, chitosan-blended polyvinyl alcoho as support material, and glutaraldehyde as cross-linking agent. The structure and morphology of the adsorbent were characterized with FTIR, XRD, EDS, and SEM. In the presence of Cu(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), etc., the adsorption selectivity toward Pb(II) of the adsorbent in aqueous solution was studied, showing that glutaric acid modified Pb(II) imprinted chitosan-based composite membrane had a good adsorption selectivity toward Pb2+ in aqueous solution. The adsorption process of the membrane was under chemical reaction and was in line with the McKay quasi-secondary reaction kinetics model. [ABSTRACT FROM AUTHOR]

Background: The utility of 1,2-o-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin)-ester-(DGGR)-lipase activity (DLA) in monitoring clinical progression of chronic pancreatitis (CP) in dogs is unknown., Objective: To examine the association of DLA with clinical signs of CP, as assessed by a CP clinical severity score (CPCSS)., Animals: Twenty-four dogs., Methods: This is a retrospective study. Chronic pancreatitis was diagnosed based on clinical signs and DLA > 250 U/L and monitored using CPCSS and DLA., Results: The study included 134 visits (median, 10 visits/dog; range, 2-11). Mild-moderate (CPCSS, 0-3) and severe (CPCSS, ≥4) disease were documented in 94 (70%) and 40 (30%) visits, respectively. In emergency visits (n = 44; 33%) CPCSS (median, 5; range, 0-15) and DLA (median, 534 U/L; range, 63-7133) were higher (P < .001 and P = .003, respectively) than in scheduled ones (n = 90; 67%; median, 1; range, 0-6 and median, 384 U/L; range, 49-3747, respectively). DGGR-lipase activity was associated (P = .009) with the CPCSS, with a lower activity documented in mild-moderate CPCSS (median 391 U/L; range, 49-3747), compared to severe score (median, 558 U/L; range, 63-7133). DGGR-lipase activity was significantly, but weakly, correlated with CPSS (r = 0.233, P = .007). DGGR-lipase activity inefficiently discriminated mild-moderate vs severe CP (area under the receiver operator characteristics curve, 0.64; 95% confidence interval, 0.53-0.75; P = .012), with DLA cutoff of 428 U/L corresponding to sensitivity of 65% and specificity of 63%., Conclusions and Clinical Importance: Increased DLA is associated with emergency revisits in dogs with CP, possibly reflecting acute flare-ups. DGGR-lipase activity was associated with the CPCSS over the follow-ups but could not differentiate disease severity., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC. on behalf of the American College of Veterinary Internal Medicine.)

In this study, we report an enhancement of critical current density of bulk MgB2 superconductors by glutaric acid (C5H8O4) doping. The effects of glutaric acid doping on MgB2 lattice resulted in a record self-field Jc of the order of 106 A/cm2. A simultaneous improvement in the connectivity, pinning force, and Hc2 is the major factor that determined excellent Jc performance. X-ray diffraction analysis showed that samples were single-phase MgB2 with a minor trace of impurities. A dramatic change in grain morphology and homogeneity in grain distribution was found in the SEM images of doped samples. We observed that homogeneity in grain distribution played a crucial role in the connectivity and the upper critical field (Hc2) of the doped samples. We were able to introduce a new dopant through a two-step mixing approach which is suitable to overcome the degradation of low field and self-field Jc reported for carbon-doped MgB2 superconductor samples. [ABSTRACT FROM AUTHOR]

Novel heterogeneous tungsten species in mesoporous silica SBA‐16 catalysts based on ship‐in‐a‐bottle methodology are originally reported for oxidizing cyclopentene (CPE) to glutaric acid (GAC) using hydrogen peroxide (H2O2). For all W‐SBA‐16 catalysts, isolated tungsten species and octahedrally coordinated tungsten oxide species are observed while WO3 crystallites are detected for the W‐SBA‐16 catalysts with Si/ W = 5, 10, and 20. The specific surface areas and the corresponding total pore volumes decrease significantly as increasing amounts of tungsten incorporated into the pores of SBA‐16. Using tungsten‐substituted mesoporous SBA‐16 heterogeneous catalysts, high yield of GAC (55%) is achieved with low tungsten loading (for Si/W = 30, ~13 wt%) for oxidation of CPE. The W‐SBA‐16 catalysts with Si/W = 30 can be reused five times without dramatic deactivation. In fact, low catalytic activity provided by bulk WO3 implies that the highly distributed tungsten species in SBA‐16 and the steric confinement effect of SBA‐16 are key elements for the outstanding catalytic performance. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of organic acids, added to the electrolytic solution, on the structure, morphology, and corrosion behaviour of plasma electrolytic oxidation (PEO) coatings produced on titanium grade 2. Particular attention is paid to the role of functional groups in the modification of the oxide's properties. For this reason, all three selected acids, namely glutaric, glutamic, and tartaric acid, display two carboxylic groups, thus they interact with the substrate material mainly through –COO− adsorption. However, glutamic acid also has an amine group, while tartaric acid has two hydroxyl groups. The presence of such additional functional groups is found to impact the formation of the PEO coatings. According to scanning electron microscopy (SEM) analyses, the number of defects and their dimension increase with an increasing number of active groups present in the organic molecules. Then, when glutaric acid with only two carboxyl groups, is employed as an additive, smaller pores are produced. The dimension of defects increases when glutamic and tartaric acid are used. X-ray diffraction (XRD) testing demonstrates that rutile and anatase are present in all the coatings and that when using tartaric acid, a relatively high level of amorphism is reached. The electrochemical and corrosion behaviours are evaluated by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) performed in a heated sulphuric acid solution. It is found that all types of coatings provide protection against corrosion, with oxides produced using glutamic acid showing the lowest corrosion current density (0.58 mA·m−2) and low corrosion rate (1.02 μm·y−1). [ABSTRACT FROM AUTHOR]

Dicarboxylic acids are prevalent in the atmosphere and frequently investigated by aerosol and atmospheric scientists. Glutaric acid, being a water-soluble dicarboxylic acid, is commonly used to model water activity in dicarboxylic acid aerosols. Different values associated with glutaric acid aerosols, specifically DRH and hygroscopic data, have been reported by several groups. We hypothesize that this variability is caused by its polymorphism. Glutaric acid exhibits dimorphism, meaning the molecule can form into two different types of crystal structures, an alpha and a beta polymorph. Glutaric acid naturally forms the beta polymorph, which is more stable. The alpha polymorph is the metastable phase. These polymorphs manifest themselves as a bimodal aerosol size distribution when analyzed by Scanning Mobility Particle Sizers or other aerosol mobility sizing methods. In this article, we discuss the formation of the nanoscale alpha glutaric acid polymorph generated from an aqueous glutaric acid solution. The formation of both polymorphs from an aqueous solution has not been documented elsewhere. We have found that the alpha polymorph forms at faster crystallization speeds, with a lower aqueous solution concentration and a lower solution flow rate into the atomizer. This identification of the presence of polymorphism in glutaric acid aerosols under common laboratory generation conditions could explain the variability present in studies associated with glutaric acid aerosols. Understanding the conditions at which the alpha polymorph is present will allow researchers to avoid it when using glutaric acid as a dicarboxylic acid standard and explain previously noted discrepancies. Copyright © 2019 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Quinolinate and Glutaric acid exert a toxic synergism in neuronal cells. • The toxic model was tested in rat cultured neurons and cortical slices. • The cannabinoid anandamide prevented toxic endpoints of synergism. • Anandamide protection involved the partial participation of CB1 receptors. • Novel mechanisms involved in Glutaric Acidemia type I are suggested. Abstract The endocannabinoid system (ECS) regulates several physiological processes in the Central Nervous System, including the modulation of neuronal excitability via activation of cannabinoid receptors (CBr). Both glutaric acid (GA) and quinolinic acid (QUIN) are endogenous metabolites that, under pathological conditions, recruit common toxic mechanisms. A synergistic effect between them has already been demonstrated, supporting potential implications for glutaric acidemia type I (GA I). Here we investigated the possible involvement of a cannabinoid component in the toxic model exerted by QUIN + GA in rat cortical slices and primary neuronal cell cultures. The effects of the CB1 receptor agonist anandamide (AEA), and the fatty acid amide hydrolase inhibitor URB597, were tested on cell viability in cortical brain slices and primary neuronal cultures exposed to QUIN, GA, or QUIN + GA. As a pre-treatment to the QUIN + GA condition, AEA prevented the loss of cell viability in both preparations. URB597 only protected in a moderate manner the cultured neuronal cells against the QUIN + GA-induced damage. The use of the CB1 receptor reverse agonist AM251 in both biological preparations prevented partially the protective effects exerted by AEA, thus suggesting a partial role of CB1 receptors in this toxic model. AEA also prevented the cell damage and apoptotic death induced by the synergic model in cell cultures. Altogether, these findings demonstrate a modulatory role of the ECS on the synergic toxic actions exerted by QUIN + GA, thus providing key information for the understanding of the pathophysiological events occurring in GA I. [ABSTRACT FROM AUTHOR]

Organic acid assistance is one of the effective methods for phytoremediation of heavy metal contaminated soil. In this experiment, the addition of citric and glutaric acids was selected to improve the accumulation of cadmium and lead by Helianthus annuus L. Results showed that citric and glutaric acids elevated the growth of the plants and stimulated Cd/Pb uptake by plant in single Cd/Pb treatments, but glutaric acid showed inhibitory action on the uptake of metals in complex treatments. Organic acids impacted the translocation of Cd/Pb differently, and citric acids (30 mg·L -1 ) enhanced the translocation of Cd to aerial parts of the plants in Cd (5 mg·kg -1 ) and Cd (10 mg·kg -1 ) plus Pb treatments. Glutaric acid (30 mg·L -1 ) could promote the translocation factors in the complex treatments of Cd (5 mg·kg -1 ) with Pb (50, 100 mg·kg -1 ) added. The application of citric and glutaric acid could be conducive to increase floral growth when proper doses are used, and incorporation of these organic acids can be a useful approach to assist cadmium and lead uptake by sunflower. However, growth, bioaccumulation, and translocation of metals may differ due to the metals' property, kinds, and concentrations of organic acids.