• 한국미생물·생명공학회지
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• 제24권2호
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• pp.137-142
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• 1996

The biosynthesis and catabolite repression of cyclodextrin glucanotransferase(CGTase) and cyclodextrinase(CDase) were studied in Bacillus sp. KJI6. In accompanying to the cell growth, CGTase was synthesized during early growth phase (20h culture) and CDase was synthesized during late growth phase (60h culture). Synthesis of CGTase was rather constitutive than that of CDase in the absence or presence of carbon source. Production of CDase was strongly stimulated by amylopectin and $\gamma$-CD medium (about 6 times), but CGTase synthesis was slightly increased (about 1.3 times). Easily metabolizable carbohydrates such as D-glucose, D- fructose and D-mannose completely repressed the expression of CDase, whereas their repressive effect to CGTase synthesis was relatively negligible. By addition of 10 mM cAMP, any significant effect on the synthesis of the two enzymes was not observed. Hardly metabolizable glucose analogues such as 2-deoxy-D-glucose and 3-0-methyl-D-glucopyranose also did not show any repression on the syntheses of CGTase and CDase. This indicates that D-glucose has to be metabolized to exert its repressive effect. With these results, it seems likely that the biosynthesis of CGTase and CDase are regulated by the catabolite repression due to unknown metabolite(s) of EM pathway.

• 한국식품위생안전성학회지
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• 제8권4호
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• pp.195-204
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• 1993

Basolateral and brush border membrane (BLM and BBM) vesicles of renal proximal tubules were prepared from adult male New Zealand White rabbits to evaluate as a potential model for assessment of nephrotoxicity. PAH uptakes using BLMV, glucose and leucine uptakes using BBMV were measured in the rabbits treated cephaloridine. In addition, urinalysis and histopathological studies were performed to investigate the correlationship with membrane vesicle uptakes. The results were as follows: (1) the activite of Na+, K+ -ATPase was enriched 12.3-fold in vasolateral memvrane vesicles (BLMV) and the specific activity of alkaline phosphatase in purified brush border memvrane vesicles (BBMV) was enriched 10.1-fold compared with each of microsomal homogenate. (2) In the uptake experiments, cephaloridine decreased initial and probenecid-sensitive PAH uptakes in BLMV. (3) Cephaloridine tested decreased initial and phlorizin-sensitive glucose uptakes in BBMV. (4) Cephaloridine tested decreased initial and Na+-dependent leucine uptakes in BBMV. (5) Cephaloridine tested significantly increased the urinary excretion of glucose and activity of ${\gamma}$-GTP. (6) Cephaloridine tested caused moderate necrotic changes in renal tubular cells and formation of urinary cast in the lumina of Henle's loop and collecting tubules besides the swelling of renal tubules.

• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.491-496
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• 2005

The biosynthetic gene cluster for the aminoglycoside antibiotic kasugamycin was isolated and characterized from the kasugamycin producing strain, Streptomyces kasugaensis KACC 20262. By screening a fosmid library using kasA, the gene encoding aminotransferase, we isolated a 22 kb DNA fragment. The fragment contained seventeen complete open reading frames (ORFs); one of these ORFs, kasD, was identified as the gene for dNDP-glucose 4,6-dehydratase, which catalyzes the conversion of dNDP-glucose to 4-keto-6-deoxy-dNDP-glucose. The enzyme showed a broad spectrum of substrate specificity. In addition, ksR was overexpressed in E. coli BL21 and proved to be a self-resistance gene against kasugamycin. These findings suggest that the isolated gene cluster is highly likely responsible for the biosynthesis of kasugamycin.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.539-545
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• 2014

Styrene-acrylamide co-polymer was immobilized on porous partially sub-$2{\mu}m$ silica monolith particles and inner surface of fused silica capillary ($50{\mu}m$ ID and 28 cm length) to result in ${\mu}LC$ and CEC stationary phases, respectively, for separation of anomeric D-glucose derivatives. Reversed addition-fragmentation transfer (RAFT) polymerization was incorporated to induce surface polymerization. Acrylamide was employed to incorporate amide-functionality in the stationary phase. The resultant ${\mu}LC$ and CEC stationary phases were able to separate isomers of D-glucose derivatives with high selectivity and efficiency. The mobile phase of 75/25 (v/v) acetonitrile (ACN)/water with 0.1% TFA, was used for HPLC with a packed column (1 mm ID, 300 mm length). The effects of pH and ACN composition on anomeric separation of D-glucose in CEC have been examined. A mobile phase of 85/15 (v/v) ACN/30 mM sodium acetate pH 6.7 was found the optimized mobile phase for CEC. The CEC stationary phase also gave good separation of other saccharides such as maltotriose and Dextran 1500 (MW~1500) with good separation efficiency (number of theoretical plates ~300,000/m).

• 대한약리학회지
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• 제16권1호
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• pp.9-14
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• 1980

To evaluate the adrenergic receptors for glycogenolytic responses to catecholamine, the blood glucose level, liver glycogen content and muscle glycogen level in rats were studied with treatment of epinephrine, norepinephrine and isoproterenol. In addition, to study the possibility of interconversion of adrenergic receptors, the effects of catecholamines in feeding animal were compared with those in fasting animal. The results are summarized as follow; 1) Epinephrine and norepinephine showed dose dependent increase of blood glucose level but the effect of isproterenol was not significant. 2) The prandial states of animal did not influence on effects of catecholamines on blood glucose level. 3) Liver glycogen contents were lowered by epinephrine or by norepinephrins but effect of isoproterenol was not significant. 4) Glycogen content of skeletal muscle was significantly lowered by isoproterenol and. epinephrine shifted the dose-response curve to right, but the effect of norepinephrine was not significant. 5) The effects of epinephrine and norepinephrine on blood glucose were significantly blocked by ergotamine but not by propranolol. These results indicate that the glycogenolytic response to adrenergic agents in rat is mediated by an alpha-receptor in liver and by a beta-receptor in skeletal muscle.

• 동의생리병리학회지
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• 제25권2호
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• pp.264-269
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• 2011

This study was designed to investigate the effects of Cinnamomi Cortex extract (CC) on hypercholesterolemia induced by Estradiol valerate (EV) in female rats. We investigated the effects of CC on Changes in body weights for 5 weeks. In addition, we examined the effects on fasting blood glucose (FBS) and tested oral glucose tolerance test after oral administration of CC for 5 weeks. We also investigated the effects on levels of total cholesterol, HDL-cholesterol and LDL-cholesterol in serum. Treatment with CC restored weight gain rates suppressed by EV significantly. CC did not affect serum glucose level and glucose tolerance. Levels of total cholesterol and triglyceride were lowered by administration of CC compared to EV treated control respectively. These result suggest that CC can lower serum cholesterol level then prevent weight loss induced by EV. We also suggest the possibility as anti-hyperlipidemic agent of CC.

• 대한의생명과학회지
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• 제28권4호
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• pp.284-289
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• 2022

Hypertension is associated with cardiovascular disease. The environmental and genetic factors can cause the development of hypertension. In this study, the relationship between hypertension and family history of hypertension in Koreans was analyzed in consideration of serum fasting blood glucose levels and age. The study subjects were 2,484 subjects who had a medical examination at a university hospital. The main statistical analysis method was multiple logistic regression analysis. Hypertension prevalence was 16.4% of all subjects, and subjects with a family history of hypertension were 23.5%. The risk of hypertension was 2.36 times higher in subjects with a family history of hypertension than subjects without a family history of hypertension. In addition, in the subjects with fasting blood glucose levels more than 120 mg/dL, the risk of hypertension was 4.44 times higher in subjects with a family history of hypertension compared with subjects without a family history of hypertension. The relationship between family history and hypertension was slightly higher in the older group than in the younger group. To assess the association between hypertension and family history, further cohort study is necessary in the future.

• Journal of Microbiology and Biotechnology
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• 제33권12호
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• pp.1692-1697
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• 2023

Staphylococcus aureus integrated with mecA gene, which codes for penicillin-binding protein 2a, is resistant to all penicillins and other beta-lactam antibiotics, resulting in poor treatment expectations in skin and soft tissue infections. The development of a simple, sensitive and portable biosensor for mecA gene analysis in S. aureus is urgently needed. Herein, we propose a dual-toehold-probe (sensing probe)-mediated exonuclease-III (Exo-III)-assisted signal recycling for portable detection of the mecA gene in S. aureus. When the target mecA gene is present, it hybridizes with the sensing probe, initiating Exo III-assisted dual signal recycles, which in turn release numerous "3" sequences. The released "3" sequences initiate catalytic hairpin amplification, resulting in the fixation of a sucrase-labeled H2 probe on the surface of magnetic beads (MBs). After magnet-based enrichment of an MB-H1-H2-sucrase complex and removal of a liquid supernatant containing free sucrase, the complex is then used to catalyze sucrose to glucose, which can be quantitatively detected by a personal glucose meter. With a limit of detection of 4.36 fM for mecA gene, the developed strategy exhibits high sensitivity. In addition, good selectivity and anti-interference capability were also attained with this method, making it promising for antibiotic tolerance analysis at the point-of-care.

• 미생물학회지
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• 제43권4호
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• pp.304-310
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• 2007

Bacillus cereus 1-1 균주는 광이 없는 호기적 환경에서 levulinic acid와 같은 저해제 처리 없이도 5-aminolevulinic acid (ALA)를2 mM까지 생산하였다. B. cereus 1-1 균주는 TCY 배지에서 전 배양과 본 배양을 18시간 동안 지속하고, 배지의 pH가 6.8에 도달하는 대수기 후기에 acetic acid를 비롯한 유기산들을 16 mM 첨가하였을 때 많은 ALA를 생산하였으며, 본 배양 시작시 0.3% glucose를 첨가하는 것이 효과적이었다. Acetic acid 대신 glutamic acid를 첨가하였을 때 ALA 생산이 8시간 이상 지속되었고, $40\;{\mu}M$의 gabaculine을 첨가하면 생산이 현저히 저해되는 것으로 보아 B. cereus 1-1 균의 ALA 생산은 C-5 경로에 의함을 알 수 있었다.

• Journal of Microbiology
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• 제45권3호
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• pp.199-204
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• 2007

The objective of this study was to evaluate the effect of soluble carbohydrates (glucose, cellobiose), pH (6.0, 6.5, 7.0), and rumen microbial growth factors (VFA, vitamins) on biohydrogenation of linoleic acid (LA) by mixed rumen fungi. Addition of glucose or cellobiose to culture media slowed the rate of biohydrogenation; only 35-40% of LA was converted to conjugated linoleic acid (CLA) or vaccenic acid (VA) within 24 h of incubation, whereas in the control treatment, 100% of LA was converted within 24 h. Addition of VFA or vitamins did not affect biohydrogenation activity or CLA production. Culturing rumen fungi at pH 6.0 slowed biohydrogenation compared with pH 6.5 or 7.0. CLA production was reduced by pH 6.0 compared with control (pH 6.5), but was higher with pH 7.0. Biohydrogenation of LA to VA was complete within 72 h at pH 6.0, 24 h at pH 6.5, and 48 h at pH 7.0. It is concluded that optimum conditions for biohydrogenation of LA and for CLA production by rumen fungi were provided without addition of soluble carbohydrates, VFA or vitamins to the culture medium; optimum pH was 6.5 for biohydrogenation and 7.0 for CLA production.