• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.19-26
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• 2020

Medium- and long-chain triglyceride (MCT/LCT) propofol is widely used as an intravenous anesthetic, especially in the intensive care unit. The present study aimed to assess whether MCT/LCT propofol is safe in the hyperlipidemic population for long-term use. Free fatty acids (FFAs) were used to establish high-fat stimulation of HepG2 and Huh7 cells. Subsequently, these cells were treated with propofol at the concentration of 0, 4, or 8 ㎍/ml for 24 and 48 h. The results indicated that the cell viability was notably decreased when the cells were stimulated with 2 mmol/L FFAs and treated with 12 ㎍/ml MCT/LCT propofol. Accordingly, we chose 2 mmol/L FFAs along with 4 and 8 ㎍/ml MCT/LCT propofol for the subsequent experiments. Four and 8 ㎍/ml MCT/LCT propofol inhibited FFA-induced lipid accumulation in the cells and significantly reversed acetyl coenzyme A carboxylase (ACC) activity. In addition, MCT/LCT propofol not only significantly promoted the phosphorylation of AMPK and ACC, but also reversed the FFA-induced decreased phosphorylation of AMPK and ACC. In conclusion, MCT/LCT propofol reverses the negative effects caused by FFAs in HepG2 and Huh7 cells, indicating that MCT/LCT propofol might positively regulate lipid metabolism.

• BMB Reports
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• v.33 no.4
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• pp.317-320
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• 2000

The succinic semialdehyde dehydrogenase from bovine brain was inactivated by treatment with phenylglyoxal, a reagent that specifically modifies arginine residues. The inhibition at various phenylglyoxal concentrations shows pseudo-first-order kinetics with an apparent secondorder rate constant of 30 $M^{-1}min^{-1}$ for inactivation. Partial protection against inactivation was provided by the coenzyme $NAD^+$, but not by the substrate succinic semialdehyde. Spectrophotometric studies indicated that complete inactivation of the enzyme resulted from the binding of 2 mol phenylglyoxal per mol of enzyme. These results suggest that essential arginine residues, located at or near the coenzyme-binding site, are connected with the catalytic activity of brain succinic semialdehyde dehydrogenase.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.409-412
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• 2015

Changes in the contents of mevinolins (natural statins, $0-568.18{\mu}g$), coenzyme Q10 (CoQ10, $26.41-65.59{\mu}g$), and tocopherols ($232.80-312.87{\mu}g/g$ dry weight) in Monascus-fermented soybean were determined using HPLC. Significant increases (p<0.05) in mevinolins and CoQ10 were obtained in Monascus-fermented soybean after 20 days of fermentation compared with unfermented soybean (0 days), whereas no significant change (p>0.05), or a slight decrease, in tocopherols was observed. The results indicate that Monascus-fermentation has great potential for enriching mevinolin and CoQ10 in soybeans.

• Korean Journal of Microbiology
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• v.29 no.1
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• pp.40-48
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• 1991

Two malonate-specific enzymes, malonyl-CoA synthetase and malonamidase, were found in free-living cultures of Rhizobium japonicum, Rhizobium meliloti, and Rhizobium trifolii, that infect plant roots where contain a high concentration of malonate. Malonyl-CoA synthetase catalyzes the formation of malonyl-CoA, AMP, and PPi directly from malonate, coenzyme A, and ATP in the presence of $Mg^{2+}$ Malonamidase is a novel enzyme that catalyzes hydrolysis and malonyl transfer of malonamate, and forms malonohydroxamate from malonate and hydroxylamine. Both enzymes are highly specific for malonate. These results show that Rhizobia have enzymes able to metabolize malonate and suggest that malonate may be used in symbiotic carbon and nitrogen metabolism.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.184-187
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• 2002

Lovastatin is a cholesterol-lowering agent, which plays a role of an inhibitor of 3-hydroxy-3- methylglutaryl coenzyme A reductase (HMG-CoA). When thiamine was supplemented in 3L batch fermentation, the production of lovastatin was improved. At the same time, the levels of pyruvic acid and NAD(P)H were estimated in the course of the fermentation of A. terreus. For the high level production of lovastatin, semi fed-batch fermentation was performed. And the thiamine level was maintained to a concentration of 20 mg/L and glucose was supplied. The final dry cell weight was lowered by 30 % and final lovastatin concentration was increased by 33 %. Final lovastatin concentration of 3.3 g/L was achieved in 8 days.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.647-649
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• 2006

Mevinolin, a fungal metabolite, is a potent inhibitor of 3-hydroxy-methyl-3-glutaryl-coenzyme A (HMG-CoA) reductase, the rate-controlling enzyme in cholesterol biosynthesis. In this investigation, the optimum factors for mevinolin production by Monascus pilosus IFO 480 in soymeal fermentation were studied. The highest yield of mevinolin, 2.82 mg mevinolin per g dry weight, without citrinin (a toxic fungal secondary metabolite) was obtained after 21 days of fermentation at $30^{\circ}C$ at 65% moisture content, particle size 0.6-0.9 mm, and initial substrate pH of 6.0. Mevinolin was present in the fermentation substrate predominantly in the hydroxycarboxylate form (open lactone, 92.1-97.3%), which is currently being used as a hypocholesterolemic agent.

• The Plant Pathology Journal
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• v.37 no.6
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• pp.673-680
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• 2021

Acidovorax citrulli (Ac) is the causative agent of bacterial fruit blotch disease in watermelon. Since resistant cultivars have not yet been developed, the virulence factors/mechanisms of Ac need to be characterized. This study reports the functions of a putative pyridoxal phosphate-dependent aminotransferase (PpdaAc) that transfers amino groups to its substrates and uses pyridoxal phosphate as a coenzyme. It was observed that a ppdaAc knockout mutant had a significantly reduced virulence in watermelon when introduced via germinated-seed inoculation as well as leaf infiltration. Comparative proteomic analysis predicted the cellular mechanisms related to PpdaAc. Apart from causing virulence, the PpdaAc may have significant roles in energy production, cell membrane, motility, chemotaxis, post-translational modifications, and iron-related mechanisms. Therefore, it is postulated that PpdaAc may possess pleiotropic effects. These results provide new insights into the functions of a previously unidentified PpdaAc in Ac.

• Clinical and Experimental Pediatrics
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• v.57 no.7
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• pp.329-332
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• 2014

3-methylcrotonyl-coenzyme A carboxylase (3MCC) deficiency is an autosomal recessive disorder in which leucine catabolism is hampered, leading to increased urinary excretion of 3-methylcrotonylglycine. In addition, 3-hydroxyisovalerylcarnitine levels increase in the blood, and the elevated levels form the basis of neonatal screening. 3MCC deficiency symptoms are variable, ranging from neonatal onset with severe neurological abnormality to a normal, asymptomatic phenotype. Although 3MCC deficiency was previously considered to be rare, it has been found to be one of the most common metabolic disorders in newborns after the neonatal screening test using tandem mass spectrometry was introduced. Additionally, asymptomatic 3MCC deficient mothers have been identified due to abnormal results of unaffected baby's neonatal screening test. Some of the 3MCC-deficient mothers show symptoms such as fatigue, myopathy, or metabolic crisis with febrile illnesses. In the current study, we identified an asymptomatic 3MCC deficient mother when she showed abnormal results during a neonatal screening test of a healthy infant.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.365-366
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• 2007

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.510.1-510
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• 1986

Many enzymes require the participation of readily dissociable coenzymes as NAD for thir catalytic activities. The continuous utilization of the enzymes requires the retention and regeneration of the coenzymes. For this purpose, several kinds of macromolecular NAD derivatives have been prepared by covalently attaching NAD to watersoluble polymers. We have prepared poly (ethylene glycol)-bound NAD (PEG-NAD) by coupling N$\^$6/-(2-carboxyethyl)-NAD to one terminal of ${\gamma}$ $\omega$-diaminoly (ethylene glycol) (Mr 3000) with water-soluble carbodiimide. PED-NAD thus obtained has one NAD moiety located at a terminal of the linear, flexible and hydrophilic chain of poly (ethylene glycol). PED-NAD has good coenzyme activity for various dehydrogenases and is applicable in a continuous enzyme reactor. To use these macromolecular NAD derivatives in an enzyme reactor, it si necessary to understand the behavior of the system in which the reactions of dehydrogenases are coupled by the recycling of the NAD derivative. We investigated the kinetic properties of a continuous enzyme reactor containing lactate dehydrogenase, alcohol dehydrogenase and PEG-NAD. The steady-state behavior of the enzyme reactor is explained by a simple kinetic model.