Salicylate 2-O-β-d-glucoside (SAG) is a derivative of salicylate in plants. Recent reports showed that SAG could be considered as a potential anti-inflammatory substance due to its anti-inflammatory and analgesic effects, and less irritation compared with salicylic acid and aspirin. The biological method uses renewable resources to produce salicylic acid compounds, which is more environmentally friendly than traditional industry methods. In this study, Escherichia coli Tyr002 was used as the starting strain, and a salicylic acid producing strain of E. coli was constructed by introducing the isochorismate pyruvate lyase gene pchB from Pseudomonas aeruginosa. By regulating the expression of the key genes in the downstream aromatic amino acid metabolic pathways, the titer of salicylic acid reached 1.05 g/L in shake flask fermentation. Subsequently, an exogenous salicylic acid glycosyltransferase was introduced into the salicylic acid producing strain to glycosylate the salicylic acid. The newly engineered strain produced 5.7 g/L SAG in shake flask fermentation. In the subsequent batch fed fermentation in a 5 L fermentation tank, the titer of SAG reached 36.5 g/L, which is the highest titer reported to date. This work provides a new route for biosynthesis of salicylate and its derivatives.
Escherichia coli/genetics* ; Glucosides ; Metabolic Engineering ; Salicylic Acid ; Pyruvic Acid

OBJECTIVE: To explore the clinical characteristics and variants of ATP7A gene in a child with Menkes disease. METHODS: A child with Menkes disease diagnosed at the West China Second Hospital of Sichuan University and its family members in March 2022 was selected as the study subjects. Clinical manifestations and results of laboratory tests and genetic testing were summarized. RESULTS: The main manifestations of the child included seizures, global development delay, facial dysmorphism, sparse and curly hair, increased lactate and pyruvate, and significantly decreased cuprin. EEG showed frequent issuance of multifocal spikes, spines, polyspines (slow) and polymorphic slow waves. Multiple tortuous vascular shadows were observed on cranial MRI. Whole exome sequencing revealed that the child has harbored a hemizygous c.3076delA (p.ile1026*) variant of the ATP7A gene, which was inherited from his mother. The variant may lead to premature termination of protein translation. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted as pathogenic (PVS1+PM2+PP4). CONCLUSION The c.3076delA (p.Ile1026*) variant of the ATP7A gene probably underlay the Menkes disease in this child. Above finding has provided evidence for clinical diagnosis. The significantly increased lactic acid and pyruvate can be used as a reference for the diagnosis and management of Menkes disease. Microscopic abnormalities in the hair of the carriers may also facilitate their diagnosis.
Child ; Humans ; Copper-Transporting ATPases/genetics* ; East Asian People ; Menkes Kinky Hair Syndrome/genetics* ; Mutation ; Pedigree ; Peptide Fragments ; Pyruvic Acid

ω-transaminase (ω-TA) is a natural biocatalyst that has good application potential in the synthesis of chiral amines. However, the poor stability and low activity of ω-TA in the process of catalyzing unnatural substrates greatly hampers its application. To overcome these shortcomings, the thermostability of (R)-ω-TA (AtTA) from Aspergillus terreus was engineered by combining molecular dynamics simulation assisted computer-aided design with random and combinatorial mutation. An optimal mutant AtTA-E104D/A246V/R266Q (M3) with synchronously enhanced thermostability and activity was obtained. Compared with the wild- type (WT) enzyme, the half-life t_1/2 (35 ℃) of M3 was prolonged by 4.8-time (from 17.8 min to 102.7 min), and the half deactivation temperature (T¹⁰₅₀) was increased from 38.1 ℃ to 40.3 ℃. The catalytic efficiencies toward pyruvate and 1-(R)-phenylethylamine of M3 were 1.59- and 1.56-fold that of WT. Molecular dynamics simulation and molecular docking showed that the reinforced stability of α-helix caused by the increase of hydrogen bond and hydrophobic interaction in molecules was the main reason for the improvement of enzyme thermostability. The enhanced hydrogen bond of substrate with surrounding amino acid residues and the enlarged substrate binding pocket contributed to the increased catalytic efficiency of M3. Substrate spectrum analysis revealed that the catalytic performance of M3 on 11 aromatic ketones were higher than that of WT, which further showed the application potential of M3 in the synthesis of chiral amines.
Transaminases/chemistry* ; Molecular Docking Simulation ; Amines/chemistry* ; Pyruvic Acid/metabolism* ; Enzyme Stability

BACKGROUND/OBJECTIVES: Oxidative stress is a major effector of various diseases; accordingly, antioxidants are frequently ingested in order to prevent or alleviate disease symptoms. Kimchi contains various natural antioxidants, and it is known that the functional activity varies depending on the ingredients and fermentation state. Black raspberries (BR) contain various bioactive compounds with antioxidant effects. This study investigated the antioxidant and liver-protection effects of kimchi supplemented with black raspberry juice powder (BJP). MATERIALS/METHODS: BJP-added kimchi (BAK; at 0.5%, 1%, and 2% concentrations of BJP) and control (without BJP) were prepared and fermented at 4℃ for 4 weeks. Changes in the antioxidant effects of BAK during fermentation were investigated. In addition, the protective activity of BAK against oxidative stress was investigated in a liver cirrhosis-induced animal model in vivo. RESULTS: BAK groups showed the acidity and pH of optimally ripened (OR) kimchi at 2 weeks of fermentation along with the highest lactic acid bacterial counts. Additionally, BAK groups displayed a higher content of phenolic compounds and elevated antioxidant activities relative to the control, with the highest antioxidant effect observed at 2 weeks of fermentation of OR 1% BAK. After feeding the OR 1% BAK to thioacetamide-induced liver cirrhosis rats, we observed decreased glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities and elevated superoxide dismutase activity. CONCLUSIONS: These findings showed that the antioxidant effects of OR BAK and feeding of OR 1% BAK resulted in liver-protective effects against oxidative stress.
Animals ; Antioxidants ; Bacterial Load ; Fermentation ; Glutamic Acid ; Hydrogen-Ion Concentration ; Lactic Acid ; Liver Cirrhosis ; Liver ; Models, Animal ; Oxaloacetic Acid ; Oxidative Stress ; Phenol ; Pyruvic Acid ; Rats ; Rubus ; Superoxide Dismutase

Giardia lamblia, an anaerobic, amitochondriate protozoan parasite causes parasitic infection giardiasis in children and young adults. It produces pyruvate, a major metabolic product for its fermentative metabolism. The current study was undertaken to explore the effects of pyruvate as a physiological antioxidant during oxidative stress in Giardia by cysteine-ascorbate deprivation and further investigation upon the hypothesis that oxidative stress due to metabolism was the reason behind the cytotoxicity. We have estimated intracellular reactive oxygen species generation due to cysteine-ascorbate deprivation in Giardia. In the present study, we have examined the effects of extracellular addition of pyruvate, during oxidative stress generated from cysteine-ascorbate deprivation in culture media on DNA damage in Giardia. The intracellular pyruvate concentrations at several time points were measured in the trophozoites during stress. Trophozoites viability under cysteine-ascorbate deprived (CAD) medium in presence and absence of extracellular pyruvate has also been measured. The exogenous addition of a physiologically relevant concentration of pyruvate to trophozoites suspension was shown to attenuate the rate of ROS generation. We have demonstrated that Giardia protects itself from destructive consequences of ROS by maintaining the intracellular pyruvate concentration. Pyruvate recovers Giardia trophozoites from oxidative stress by decreasing the number of DNA breaks that might favor DNA repair.
Child ; Culture Media ; DNA Breaks ; DNA Damage ; DNA Repair ; Giardia lamblia ; Giardia ; Giardiasis ; Humans ; Metabolism ; Oxidative Stress ; Parasites ; Pyruvic Acid ; Reactive Oxygen Species ; Trophozoites ; Young Adult

The purpose of this study was to investigate the relationship between serum tumor markers and dietary intakes in healthy adults to address a nutrition guide for cancer prevention. We analyzed tumor-related markers, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), prostate-specific antigen (PSA), and cancer antigen 125 (CA125) in serum and daily food and nutrient intakes using a 24-hour recall method in 23 healthy men and 32 healthy women. The average age was 50.7 years for men and 48.9 years for women. There were no significant differences in biochemical tumor markers and food intake between the men and women except energy intake. A significantly positive correlation was found between serum AFP, a biochemical marker of liver cancer, and serum glutamic oxaloacetic transaminase (GOT) and/or glutamic pyruvate transaminase (GPT) in both men and women. CEA had a significant and negative correlation with energy intake for men and food intake in women. PSA, a biomarker of prostate cancer, was significantly and positively correlated with the intake of animal iron and cholesterol in men. CA125, a biomarker of gynecologic cancers, was significantly and positively correlated with meat intake in women. As this study revealed the significant relationship between biochemical tumor markers and dietary factors, further studies are needed to elucidate the underlying mechanism of this relationship.
Adult* ; alpha-Fetoproteins ; Animals ; Aspartate Aminotransferases ; Biomarkers ; Biomarkers, Tumor ; CA-125 Antigen ; Carcinoembryonic Antigen ; Cholesterol ; Diet ; Eating ; Energy Intake ; Female ; Humans ; Iron ; Liver Neoplasms ; Male ; Meat ; Methods ; Prostate-Specific Antigen ; Prostatic Neoplasms ; Pyruvic Acid

Mitochondrial dysfunction is a hallmark of metabolic diseases such as obesity, type 2 diabetes mellitus, neurodegenerative diseases, and cancers. Dysfunction occurs in part because of altered regulation of the mitochondrial pyruvate dehydrogenase complex (PDC), which acts as a central metabolic node that mediates pyruvate oxidation after glycolysis and fuels the Krebs cycle to meet energy demands. Fine-tuning of PDC activity has been mainly attributed to post-translational modifications of its subunits, including the extensively studied phosphorylation and de-phosphorylation of the E1α subunit of pyruvate dehydrogenase (PDH), modulated by kinases (pyruvate dehydrogenase kinase [PDK] 1-4) and phosphatases (pyruvate dehydrogenase phosphatase [PDP] 1-2), respectively. In addition to phosphorylation, other covalent modifications, including acetylation and succinylation, and changes in metabolite levels via metabolic pathways linked to utilization of glucose, fatty acids, and amino acids, have been identified. In this review, we will summarize the roles of PDC in diverse tissues and how regulation of its activity is affected in various metabolic disorders.
Acetylation ; Amino Acids ; Citric Acid Cycle ; Diabetes Mellitus, Type 2 ; Fatty Acids ; Glucose ; Glycolysis ; Metabolic Diseases ; Metabolic Networks and Pathways ; Metabolism* ; Mitochondria ; Neurodegenerative Diseases ; Obesity ; Oxidative Phosphorylation ; Oxidoreductases ; Phosphoric Monoester Hydrolases ; Phosphorylation ; Phosphotransferases ; Protein Processing, Post-Translational ; Pyruvate Dehydrogenase Complex* ; Pyruvic Acid*

PURPOSE: To investigate the exchange and redistribution of hyperpolarized ¹³C metabolites between different pools by temporally analyzing the relative fraction of dual T₂* components of hyperpolarized ¹³C metabolites. MATERIALS AND METHODS: A dual exponential decay analysis of T₂* is performed for [1-¹³C] pyruvate and [1-¹³C] lactate using nonspatially resolved dynamic ¹³C MR spectroscopy from mice brains with tumors (n = 3) and without (n = 4) tumors. The values of shorter and longer T₂* components are explored when fitted from averaged spectrum and temporal variations of their fractions. RESULTS: The T₂* values were not significantly different between the tumor and control groups, but the fraction of longer T₂* [1-¹³C] lactate components was more than 10% in the tumor group over that of the controls (P < 0.1). The fraction of shorter T₂* components of [1-¹³C] pyruvate showed an increasing tendency while that of the [1-¹³C] lactate was decreasing over time. The slopes of the changing fraction were steeper for the tumor group than the controls, especially for lactate (P < 0.01). In both pyruvate and lactate, the fraction of the shorter T₂* component was always greater than the longer T₂* component over time. CONCLUSIONS: The exchange and redistribution of pyruvate and lactate between different pools was investigated by dual component analysis of the free induction decay signal from hyperpolarized ¹³C experiments. Tumor and control groups showed differences in their fractions rather than the values of longer and shorter T₂* components. Fraction changing dynamics may provide an aspect for extravasation and membrane transport of pyruvate and lactate, and will be useful to determine the appropriate time window for acquisition of hyperpolarized ¹³C images.
Animals ; Brain ; Lactic Acid ; Magnetic Resonance Spectroscopy ; Membranes ; Mice ; Pyruvic Acid

BACKGROUND/OBJECTIVES: The study was conducted to evaluate the effects of dietary leucine supplementation on mitochondrial biogenesis and energy metabolism in the liver of normal birth weight (NBW) and intrauterine growth-retarded (IUGR) weanling piglets. MATERIALS/METHODS: A total of sixteen pairs of NBW and IUGR piglets from sixteen sows were selected according to their birth weight. At postnatal day 14, all piglets were weaned and fed either a control diet or a leucine-supplemented diet for 21 d. Thereafter, a 2 × 2 factorial experimental design was used. Each treatment consisted of eight replications with one piglet per replication. RESULTS: Compared with NBW piglets, IUGR piglets had a decreased (P < 0.05) hepatic adenosine triphosphate (ATP) content. Also, IUGR piglets exhibited reductions (P < 0.05) in the activities of hepatic mitochondrial pyruvate dehydrogenase (PDH), citrate synthase (CS), α-ketoglutarate dehydrogenase (α-KGDH), malate dehydrogenase (MDH), and complexes I and V, along with decreases (P < 0.05) in the concentration of mitochondrial DNA (mtDNA) and the protein expression of hepatic peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α). Dietary leucine supplementation increased (P < 0.05) the content of ATP, and the activities of CS, α-KGDH, MDH, and complex V in the liver of piglets. Furthermore, compared to those fed a control diet, piglets given a leucine-supplemented diet exhibited increases (P < 0.05) in the mtDNA content and in the mRNA expressions of sirtuin 1, PGC-1α, nuclear respiratory factor 1, mitochondrial transcription factor A, and ATP synthase, H+ transporting, mitochondrial F1 complex, β polypeptide in liver. CONCLUSIONS: Dietary leucine supplementation may exert beneficial effects on mitochondrial biogenesis and energy metabolism in NBW and IUGR weanling piglets.
Adenosine Triphosphate ; Birth Weight* ; Citrate (si)-Synthase ; Diet ; DNA, Mitochondrial ; Energy Metabolism* ; Fetal Growth Retardation ; Leucine* ; Liver ; Malate Dehydrogenase ; Nuclear Respiratory Factor 1 ; Organelle Biogenesis* ; Oxidoreductases ; Parturition* ; Peroxisomes ; Pyruvic Acid ; Research Design ; RNA, Messenger ; Sirtuin 1 ; Transcription Factors

Glioblastoma multiforme (GBM) is the most common and aggressive form of brain tumors. GBMs, like other tumors, rely relatively less on mitochondrial oxidative phosphorylation (OXPHOS) and utilize more aerobic glycolysis, and this metabolic shift becomes augmented under hypoxia. In the present study, we investigated the physiological significance of altered glucose metabolism and hypoxic adaptation in the GBM cell line U251 and two newly established primary GBMs (GBM28 and GBM37). We found that these three GBMs exhibited differential growth rates under hypoxia compared to those under normoxia. Under normoxia, the basal expressions of HIF1α and the glycolysis-associated genes, PDK1, PDK3, and GLUT1, were relatively low in U251 and GBM28, while their basal expressions were high in GBM37. Under hypoxia, the expressions of these genes were enhanced further in all three GBMs. Treatment with dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), induced cell death in GBM28 and GBM37 maintained under normoxia, whereas DCA effects disappeared under hypoxia, suggesting that hypoxic adaptation dominated DCA effects in these GBMs. In contrast, the inhibition of HIF1α with chrysin suppressed the expression of PDK1, PDK3, and GLUT1 and markedly promoted cell death of all GBMs under both normoxia and hypoxia. Interestingly, however, GBMs treated with chrysin under hypoxia still sustained higher viability than those under normoxia, and chrysin and DCA co-treatment was unable to eliminate this hypoxia-dependent resistance. Together, these results suggest that hypoxic adaptation is critical for maintaining viability of GBMs, and targeting hypoxic adaptation can be an important treatment option for GBMs.
Anoxia ; Brain Neoplasms ; Cell Death* ; Cell Line ; Dichloroacetic Acid ; Glioblastoma* ; Glucose ; Glycolysis ; Metabolism ; Oxidative Phosphorylation ; Oxidoreductases ; Phosphotransferases ; Pyruvic Acid