• Journal of Microbiology and Biotechnology
• /
• 제30권10호
• /
• pp.1574-1582
• /
• 2020

Flavonoids have diverse biological functions in human health. All flavonoids contain a common 2-phenyl chromone structure (C6-C3-C6) as a scaffold. Hence, in using such a scaffold, plenty of high-value-added flavonoids can be synthesized by chemical or biological catalyzation approaches. (2S)-Naringenin is one of the most commonly used flavonoid scaffolds. However, biosynthesizing (2S)-naringenin has been restricted not only by low production but also by the expensive precursors and inducers that are used. Herein, we established an induction-free system to de novo biosynthesize (2S)-naringenin in Escherichia coli. The tyrosine synthesis pathway was enhanced by overexpressing feedback inhibition-resistant genes (aroG^fbr and tyrA^fbr) and knocking out a repressor gene (tyrR). After optimizing the fermentation medium and conditions, we found that glycerol, glucose, fatty acids, potassium acetate, temperature, and initial pH are important for producing (2S)-naringenin. Using the optimum fermentation medium and conditions, our best strain, Nar-17LM1, could produce 588 mg/l (2S)-naringenin from glucose in a 5-L bioreactor, the highest titer reported to date in E. coli.

• Journal of Microbiology
• /
• 제39권3호
• /
• pp.149-153
• /
• 2001

The electron transfer reaction is one of the most essential processes of life. Not only does it provide the means of transforming solar and chemical energy into a utilizable form for all living organisms, it also extends into a range of metabolic processes that support the life of a cell. Thus, it is of great interest to understand the physical basis of the rates and reduction potentials of these reactions. To identify the major determinants of reduction potentials in redox proteins, we have chosen the simplest electron transfer protein, rubredoxin, a small (52-54 residue) iron-sulfur protein family, widely distributed in bacteria and archaea. Rubredoxins can be grouped into two classes based on the correlation of their reduction potentials with the identity of residue 44; those with Ala44 (ex: Pyrococcus furiosus) have reduction potentials that are ∼50 mV higher than those with Va144 (ex: Clostridium pasteurianum). Based on the crystal structures of rubredoxins from C. pasteurianum and P. furiosus, we propose the identity of residue 44 alone determines the reduction potential by the orientation of the electric dipole moment of the peptide bond between 43 and 44. Based on 1.5 $\AA$ resolution crystal structures and molecular dynamics simulations of oxidized and reduced rubredoxins from C. pasteurianum, the structural rearrangements upon reduction suggest specific mechanisms by which electron transfer reactions of rubredoxin should be facilitated.

• Journal of Microbiology
• /
• 제35권2호
• /
• pp.141-148
• /
• 1997

Alcaligenes xylosoxydans strain SMN3 capable of utilizing biphenyl grew not only on phenol, and benzoate, but also on salicylate. Catabolisms of biphenyl and salicylate appear to be interrelated since benzoate is a common metabolic intermediate of these compounds. Enzyme levels in the excatechol 2. 3-dioxygenas which is meta-cleavage enzyme of catechol, but did not induce catechol 1, 2-dioxygenase. All the oxidative enzymes of biphenyl and 2, 3,-dihydroxybiphenyl (23DHBP) were induced when the cells were grown on biphenyl and salicylate, respectively. Biphenyl and salicylate could be a good inducer in the oxidation of biphenyl and 2, 3-dihydroxybiphenyl. The two enzymes for the degradation of biphenyl and salicylate were induced after growth on either biphenyl or salicylate, suggesting the presence of a common regulatory element. However, benzoate could not induce the enzymes responsible for the oxidation of these compounds. Biphenyl and salicylate were good inducers for indigo formation due to the activity of biphenyl dioxygenase. These results suggested that indole oxidation is a property of bacterial dioxygenase that form cis-dihydrodiols from aromatic hydrocarbon including biphenyl.

• Korean Journal of Oriental Medicine
• /
• 제8권2호통권9호
• /
• pp.75-84
• /
• 2002

Obesity can be defined as a metabolic disease due to a increased state of fat tissue caused by an imbalance of calorie intake and use. To define genes that affected by different nutrient, we study gene expression from mice which were fed different nutrient. Epididymal and retro-peritineal adipose tissue were increase in high fat diet feeding mice compared with control, but liver and spleen were not. In serum, total cholesterol were differently increase in high fat diet feeding mice but total triglyceride and free fatty acid were not. That was maybe result of energy balance regulation in vivo system. aP2, PPART2 and FAS genes that were increased during adipogenesis were inclosed in high fat diet fed mice compared with control. In microarray assay, 1.4% of total genes were affected in epididymal adipose tissue by different nutrient. 1.1% of total genes were decreased down 0.5 fold and 0.3% were increased over 2 fold. These results indicated that many genes are affected in adipose tissue by nutrient.

• Journal of Environmental Science International
• /
• 제20권8호
• /
• pp.1031-1039
• /
• 2011

This study was conducted to examine the influences of chitosan, sericin and collagen extract complexes (1:1:1, w/w/w, CSC-F-005) in blood glucose and lipid concentrations in the sera of streptozotocin (STZ, 55 mg/kg BW, IP injection)-induced diabetic rats (SD strain) fed on experimental diets for 5 weeks. The concentrations of blood glucose, total cholesterol, HDL-cholesterol, ratio of HDL-cholesterol concentration to total cholesterol, atherosclerotic index, LDL-cholesterol, free cholesterol, cholesteryl ester, triglyceride (TG) and phospholipid (PL) in serum were effective on the metabolic regulation in diabetic rats. The activities of alkaline phosphatase (ALP) and aminotransferase (AST, ALT) in serum were lower in the extract complexes (CSC-F-005) than in the diabetic rats. The results shown above suggested that CSC-F-005 extract complexes supplementation effectively improvement of blood glucose and lipid components in the serum of STZ-induced diabetic rats.

• Journal of Environmental Science International
• /
• 제20권8호
• /
• pp.1021-1030
• /
• 2011

The objective of this study was to assess improvements caused by chitosan, sericin and collagen peptide extract complexes (1:1:1, w/w/w, CSC-F-005) in lipid concentrations in the sera of dyslipidemic rats (SD strain) fed on experimental diets for 5 weeks. Serum concentrations of total cholesterol, HDL-cholesterol, ratio of HDL-cholesterol concentration to total cholesterol, atherosclerotic index, LDL-cholesterol, free cholesterol, cholesteryl ester, triglyceride, phospholipid and blood glucose were effective on the metabolic regulation of dyslipidemic rats. The activities of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase in serum were remarkably lower in the extract complexes (CSC-F-005) than in the dyslipidemic model. From the above results shows that CSC-F-005 extract complexes were effective on the improvement of the lipid metabolism in sera of dyslipidemic rats.

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 한국생물정보시스템생물학회 2004년도 The 3rd Annual Conference for The Korean Society for Bioinformatics Association of Asian Societies for Bioinformatics 2004 Symposium
• /
• pp.39-49
• /
• 2004

When there is a lack of detailed kinetic information, dFBA(dynamic flux balance analysis) has correctly predicted cellular behavior under given environmental conditions with FBA and different ial equations. However, until now, dFBA has centered on substrate concentration, cell growth, and gene on/off, but a detailed hierarchical structure of a regulatory network has not been taken into account. For this reason, the dFBA has limited the represen tation of interactions between specific regulatory proteins and genes and the whole transcriptional regulation mechanism with environmental change. Moreover, to calculate optimal metabolic flux distribution which maximizes the growth flux and predict the b ehavior of cell system, linear programming package(LINDO) and spreadsheet package(EXCEL) have been used simultaneously. thses two software package have limited in the visual representation of simulation results and it can be difficult for a user to look at the effects of changing inputs to the models. Here, we descirbes the construction of hierarchical regulatory network with defined symbolsand the development of an integrated system that can predict the total control mechanism of regulatory elements (opero ns, genes, effectors, etc.), substrate concentration, growth rate, and optimal flux distribution with time. All programming procedures were accoplished in a visual programming environment (LabVIEW).

• Biomolecules & Therapeutics
• /
• 제26권3호
• /
• pp.225-241
• /
• 2018

Taurine is an abundant, ${\beta}-amino$ acid with diverse cytoprotective activity. In some species, taurine is an essential nutrient but in man it is considered a semi-essential nutrient, although cells lacking taurine show major pathology. These findings have spurred interest in the potential use of taurine as a therapeutic agent. The discovery that taurine is an effective therapy against congestive heart failure led to the study of taurine as a therapeutic agent against other disease conditions. Today, taurine has been approved for the treatment of congestive heart failure in Japan and shows promise in the treatment of several other diseases. The present review summarizes studies supporting a role of taurine in the treatment of diseases of muscle, the central nervous system, and the cardiovascular system. In addition, taurine is extremely effective in the treatment of the mitochondrial disease, mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), and offers a new approach for the treatment of metabolic diseases, such as diabetes, and inflammatory diseases, such as arthritis. The review also addresses the functions of taurine (regulation of antioxidation, energy metabolism, gene expression, ER stress, neuromodulation, quality control and calcium homeostasis) underlying these therapeutic actions.

• Journal of Genetic Medicine
• /
• 제10권2호
• /
• pp.81-87
• /
• 2013

Pseudohypoaldosteronism (PHA), a rare syndrome of systemic or renal mineralocorticoid resistance, is clinically characterized by hyperkalemia, metabolic acidosis, and elevated plasma aldosterone levels with either renal salt wasting or hypertension. PHA is a heterogeneous disorder both clinically and genetically and can be divided into three subgroups; PHA type 1 (PHA1), type 2 (PHA2) and type 3 (PHA3). PHA1 and PHA2 are genetic disorders, and PHA3 is a secondary disease of transient mineralocorticoid resistance mostly associated with urinary tract infections and obstructive uropathies. PHA1 includes two different forms with different severity of the disease and phenotype: a systemic type of disease with autosomal recessive inheritance (caused by mutations of the amiloride-sensitive epithelial sodium channel, ENaC) and a renal form with autosomal dominant inheritance (caused by mutations of the mineralocorticoid receptor, MR). In the kidneys, the distal nephron takes charge of the fine regulation of water absorption and ion handling under the control of aldosterone. Two major intracellular actors necessary for the action of aldosterone are the MR and the ENaC. Impairment of the intracellular aldosterone signal transduction pathway results in resistance to the action of mineralocorticoids, which leads to PHA. Herein, ion handling the distal nephron and the clinico-genetic findings of PHA are reviewed with special emphasis on PHA type 1.

• Korean journal of food and cookery science
• /
• 제23권6호
• /
• pp.1015-1024
• /
• 2007

Trans-fatty acids (TFAs) are defined as the sum of all unsaturated fatty acids that contain one or more non-conjugated double bonds in a trans configuration. Dietary trans- fatty acids originate from commercially hydrogenated oils and from dairy and meat fats. From the perspective of the food industry, partially hydrogenated vegetable oils are attractive because of their long shelf life, stability during deep-frying, and semisolidity, which can be customized to enhance the palatability of baked goods and fried foods. Although no definite differences have been documented so far between the metabolic and health effects of industrial and ruminant TFAs, the intake of industrially produced TFA has declined, and in Europe, the majority of TFAs are of ruminant origin. Due to the scientific evidence associating TFA intake with increased risk of coronary heart disease (CDH), the Korea Food and Drug Administration (KFDA) issued a final rule that requires the amount of trans fat present in foods to be declared on the nutrition label, by December 1, 2007. In addition, many food manufacturers who use partially hydrogenated oils in their products have developed, or are considering ways, to reduce or eliminate trans-fatty acids from certain food products.