• Journal of Nutrition and Health
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• v.27 no.9
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• pp.892-900
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• 1994

A variety of important roles for branched-chain amino acids in metabolic regulation has been suggested. Branched-chain $\alpha$-keto acid dehydrogenase(BCKAD) complex is a rate limiting enzyme in branched-chain amino acid metabolism. The purpose of this study was to examine the effects of exercise on the activity and activity state of branched-chain $\alpha$-keto acid dehydrogenase in rat hert and liver thssues. Forty-eight Sprague-Dawley rats were assigned into three experimental groups : sedentary control, exercised, or exercised-rested. Submaximal exercise(running) for two hours significantly increased basal activity without a change in total activity in both tissues, with a concomitiant increase in activity state of the enzyme complex. At 10 min post-exercise, heart enzyme activity significantly decreased, though not to the control level, while liver enzyme activity remained unchanged. These data suggested that the exercise-induced increase in branched-chain $\alpha$-keto acid decarboxylation in rat tissues may not be the result of enzyme synthesis, but rather is due to increased activity of the BCKAD.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.210.1-210
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• 1978

Aspergillus nidulans가 생산하는 naringinase를 ionic binding method 로써 DEAE-Sephadex A-25 를 사용하여 고정화시키는 조건과 그 고정화 효소의 성질에 대하여 검토하였다. 먼저 담체에 흡착되는 효소의 최적 pH는 6.0이었고 조제효소 110units 당 이상적인 담체량은 건조된 담체 1g이었다. 고정화 naringinase의 반응 최적 pH와 온도는 7.0과 5$0^{\circ}C$로서 native enzyme 보다 각각 높았다. 다음은 고정화 효소의 안정성에 미치는 pH와 온도의 영향으로서, pH 5에서 중성의 pH까지는 안정하였고 온도는 5$0^{\circ}C$까지는 안정하였으나 6$0^{\circ}C$ 이상에서는 뚜렷한 activity의 감소를 보였다.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.195-206
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• 1997

In order to study the effects of Ohwangsahwatang on Hyperchole-sterolemia, experimental study were performed on Hypercholesterolemia Rats induced by 2% cholesterol diet. Also the level of total cholesterol. triglyceride, LDL-cholesterol. HDL-cholesterol, phospholipid, transami-nase(GOT, GPT) were measured. The results were summerized as follows : In the model of Hypercholesterolemia induced by 2% cholesterol diet in rats, Ohwangsahwatang showed decreasing effects on total cholesterol, triglyceride, LDL-cholesterol, phospholipid level, and transaminase (GOT, GPT) activity in serum significantly, depending on the concentration, and showed increasing effects on HDL-cholesterol level in serum significantly depending on the concentration. According to the above results, Ohwangsahwatang showed significant decreasing effects on Hypercholesterolemia, and it is considered that it is appropriate to apply for Hypercholesterolemia.

• Toxicological Research
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• v.17
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• pp.329-333
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• 2001

Apoptosis is the normal physiological process of cell death essential for the maintenance of homeostasis. The function of nicotinamide adenine dinucleotide (NAD) and adenine diphosphate (ADP) ribosylation (transfer of ADP-ribose to proteins) reactions in modifying apoptosis have recently been of great interest. Recently. CD38. a type 2 transmembrane glycoprotein expressed in hematopoietic and non hematopoietic cell lines. has been reported to possess NAD glycohydrolase activity (Han. 1999) and PC-1 and CD38 NADase regulates T cells by inhibition of phosphodiesterase/pyrophosphatase activity of PC-1 by its association with glycosaminoglycan (Hozada et al., 1999). Sindhuphak et al. (2000) has reported that cervical cancer cells can be differentiated from normal cells by using FTIR (Fourier-Transformed Infrared) technique. which has characterized shifts to be due to the phosphodiester bond in nucleic acid. protein amide I&II. carbohydrate and glycogen bands. Mechanisms how phosphodiester bond shift in cervical cancer cells as compared to control cells remain to be elucidated. Suramana et al. (2000) as well as Lohitnavy and Sinhaseni (1998) have studied methomyl and colchicine effects in rat splenocytes. Lactate Dehydroge-nase Isozymes 3 (LDH3) and LDH4 were observed to increase transiently and subsided in plasma of rats exposed to 6~8 mg/kg methomyl after 48 hours. Phosphodiester bond shift of nucleic acid. detected by FTIR. was also reported (Suramana et al., 2000). We report here, after analysis of bond shift patterns. a similar bond shifts detected by FTIR spectrum observed in human cervical cells and splenocytes of rats exposed orally to 2~8 mg/kg methomyl as well as rats exposed to colchicine 2~6 mg/kg orally.

• Journal of Life Science
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• v.11 no.1
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• pp.57-64
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• 2001

The cDNA encoding human NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc GalNac ${\alpha}$2,6-Sialyltransferase (hST6GalNac IV) was isolated by screening of human fetal liver cDNA library with a DNA probe generated from the cDNA sequence of mouse ST6Gal NAc IV (mkST6GalNAc IV). The cDNA sequence included an open reading frame coding for 302 amino acids, and comparative analysis of this cDNA with mST6GalNAc IV showed that each sequence of the predicted coding region contains 88% and 85% identifies in nucleotide and amino acid levels, respecively. The primary structure of this enzyme suggested a putative domain structure, like that in other glycosyltransferases, consisting of a short N-terminal cytoplamic domain, a transmembrane domain and a large C-terminal active domain. This enzyme expressed in COS-7 cells echibited transferase activity toward NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc, fetuin and GM1b, although the activity toward the later is very low, no significant activity being detected toward Gal${\beta}$ 1,3Gal NAc or asialofetuin, the other glycoprotein substrates tested. The $^{14}$ C-sialylated residue of fetuin sialylated by this enzyem with CMP-[$^{14}$C]NeuAc was sensitive to treatment with ${\alpha}$2,8-specific sialidase of Vibrio cholerae but resistant to treatment with ${\alpha}$2,3-specific sialidase (NaNase I), and ${\alpha}$2,3- and ${\alpha}$2,8-specific sialidase of Newcastle disease virus. These results clearly indicated that the expressed enzyme is a type of GalNAc ${\alpha}$2,6-sialyltransferase like mST6GalNAc IV, which requires sialic acid residues linked to Gal${\beta}$1,3GalNAc-residues for its activity.

• KSBB Journal
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• v.9 no.4
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• pp.372-377
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• 1994

To improve L-lysine yield, pyrimidine base analogue(6-azauracil)-resistant mutants were isolated from Corynebacterium glutamicum KFCC10672 Among them the best producer, C. glutamicum CH0516, was selected and tested for L-lysine production in a $7\ell$ fermentor. It was found that the product yield obtained with C. glutamicum CH0516 was higher than that of the parent strain by 3%. In order to elucidate the gain in productivity with the 6-azauracil-resistant mutant enzymatic kinetic parameters such as aspartokinase(AKase) and aspartate carbamoyltransferase (ATCase) were measured. The Km values of AKase with C. glutamicum KFCC10672 and CH0516 were 200.0 mM and 166.7 mM and those of ATCase were 0.13 mM and 0.27 mM, respectively. However, the specific enzyme activities of AKase of C. glutamlcum KFCC10672 and CH0516 were $3.89{\times}10^{-1}$ units/mg and $4.78{\times}10^{-1}$ units/mg, and those of ATCarse were 2.20 units/mg and 1.84 units/mg, respectively. It appears that some increase in product yield with C. gluramicum CH0516 is likely due to the increased Akase activity and decreased ATCase activity.