• 미생물학회지
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• 제24권2호
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• pp.194-197
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• 1986

Malonate kinase and isocitrate lyase were induced in Acinetobacter calcoaceticus grown on malonate as a sole carbon source but repressed by succinate. The induction of those two enzymes was stimulated by dibutyryl cyclic adenosine 3', 5'-monophosphate, indicating that the expression of their genes for those enzymes is dependent on cyclic adenosine 3', 5'-monophosphate.

• 한국미생물·생명공학회지
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• 제34권4호
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• pp.289-298
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• 2006

3',5'-cyclic adenosine monophosphate (cAMP) is an important molecule, which mediates diverse cellular processes. For example, it is involved in regulation of sugar uptake/catabolism, DNA replication, cell division, and motility in various acterial species. In addition, cAMP is one of the critical regulators for syntheses of virulence factors in many pathogenic bacteria. It is believed that cAMP acts as a signal for environmental changes as well as a regulatory factor for gene expressions. Therefore, intracellular concentration of cAMP is finely modulated by according to its rates of synthesis (by adenylate cyclase), excretion, and degradation (by cAMP phosphodiesterase). In the present review, we discuss the bacterial physiological characteristics governed by CAMP and the molecular mechanisms for gene regulation by cAMP. Furthermore, the effect of cAMP on phosphotransferase system is addressed.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.442-446
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• 2010

Adenosine 3',5'-cyclic monophosphate (cAMP) is a second messenger responsible for a multitude of cellular responses. In this study, we utilized $\beta$-cyclodextrin ($\beta$-CD) as an artificial receptor with a hydrophobic cavity to elucidate the inclusion kinetics of cAMP in a hydrophobic environment using the ultrasonic relaxation method. The results revealed that the interaction of cAMP with $\beta$-CD followed a single relaxation curve as a result of host-guest interactions. The inclusion of cAMP into the $\beta$-CD cavity was found to be a diffusion-controlled reaction. The dissociation of cAMP from the $\beta$-CD cavity was slower than that of adenosine 5'-monophosphate (AMP). The syn and anti glycosyl conformations of adenine nucleotides are considered to play an important role in formation of the inclusion complex. Taken together, our findings indicate that hydrophobic interactions are involved in the inclusion complex formation of cAMP with $\beta$-CD and provide insight into the interactions of cAMP with cAMP-binding proteins.

• 한국균학회지
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• 제13권2호
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• pp.65-74
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• 1985

1. 분화과정에 따른 균체로부터 추출한 총 RNA량은 포자형성 직전에 증가함을 알았다. 2. 추출한 RNA를 가수분해하여 P.E.I. Cellulose TLC를 전개한 결과 AMP유도체와 IMP가 존재함을 확인하였다. 3. 포자형성을 전후하여 IMP와 AMP의 RNA에 대한 함량비율은 일정함을 알았다. 4. 포자형성 전기의 균체에 아데노신, 구아노신, 이노신, 크산토신을 처리한바 포자형성이 10배 이상 촉진되었다. 5. 포자형성 전기의 균체에 A. bisporus, F. velutipes, L. edodes의 열수추출액을 처리한바 포자형성이 $1.5{\sim}2$배 촉진되었다.

• Toxicological Research
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• 제4권1호
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• pp.47-53
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• 1988

Cholera toxin and dibutyryl cyclic adenosine 3', 5'-monophosphate(db-cAMP) increased the rate and number of infections units produced in the in vitro reactivation of latent herpes simplex virus, whereas adenosine diminished them. cAMP concentration in latently infected trigeminal ganglia of mice was greatly increased by cholera toxin but was not affected by adenosine.

• Journal of Applied Biological Chemistry
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• 제62권4호
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• pp.425-431
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• 2019

Platelet activation is essential for hemostatic process on blood vessel damage. However, excessive platelet activation can cause some cardiovascular diseases including atherosclerosis, thrombosis, and myocardial infarction. Scoparone is commonly encountered in the roots of genus Artemisia or Scopolia, and has been studied for its potential pharmacological properties including immunosuppression and vasorelaxation, but antiplatelet effects of scoparone have not been reported yet. We investigated the effect of scoparone on human platelet activation prompted by an analogue of thromboxane A₂, U46619. As the results, scoparone dose-dependently increased cyclic adenosine monophosphate (cAMP) levels as well as cyclic guanosine monophosphate (cGMP) levels, both being aggregation-inhibiting molecules. In addition, scoparone strongly phosphorylated inositol 1, 4, 5-triphosphate receptor (IP3R) and vasodilator-stimulated phosphoprotein (VASP), substrates of cAMP dependent kinase and cGMP dependent kinase. Phosphorylation of IP₃R by scoparone resulted in inhibition of Ca²⁺ mobilization in calcium channels in a dense tubular system, and phosphorylation of VASP by scoparone led to an inability of fibrinogen being able to bind to αIIb/β3. Finally, scoparone inhibited thrombin-induced fibrin clotting, thereby reducing thrombus formation. Therefore, we suggest that scoparone has a strong antiplatelet effect and is highly probable to prevent platelet-derived vascular disease.

• Kidney Research and Clinical Practice
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• 제35권2호
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• pp.69-77
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• 2016

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease, and its pathogenesis is complex and has not yet been fully elucidated. Abnormal glucose and lipid metabolism is key to understanding the pathogenesis of DN, which can develop in both type 1 and type 2 diabetes. A hallmark of this disease is the accumulation of glucose and lipids in renal cells, resulting in oxidative and endoplasmic reticulum stress, intracellular hypoxia, and inflammation, eventually leading to glomerulosclerosis and interstitial fibrosis. There is a growing body of evidence demonstrating that dysregulation of 50 adenosine monophosphate-activated protein kinase (AMPK), an enzyme that plays a principal role in cell growth and cellular energy homeostasis, in relevant tissues is a key component of the development of metabolic syndrome and type 2 diabetes mellitus; thus, targeting this enzyme may ameliorate some pathologic features of this disease. AMPK regulates the coordination of anabolic processes, with its activation proven to improve glucose and lipid homeostasis in insulin-resistant animal models, as well as demonstrating mitochondrial biogenesis and antitumor activity. In this review, we discuss new findings regarding the role of AMPK in the pathogenesis of DN and offer suggestions for feasible clinical use and future studies of the role of AMPK activators in this disorder.

• 한국미생물·생명공학회지
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• 제18권5호
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• pp.471-475
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• 1990

내열성 Thermus caldopilus로부터 정제된 내열성의 adenylate kinase는 nucleoside monophosphate에 대해 nucleotide triphosphate보다 높은 기질 특이성을 보여 주었다. $P',P^5$-di(adenosine-5')pentaphosphate는 여러 기질에 있어 Thermus의 adenylate kinase에 대해 경쟁적 저해제로서 작용하였다. $Mg^{2+}$ 이외 여러 가지 2가 양이온은 $Ca^{2+}, Mg^{2+}, Ba^{2+}, Fe^{2+}$ 순위로 효소활성에 필요하였으며, 효소활성은 p-chloromucuribenzoic acid와 같은 sulfurhydryl 시약에 저해되지 않았으며, 식염이나 phosphenolpyruvate을 반응액 첨가하였을 때 활성화되었다.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.145-148
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• 2009

Nucleotides are the building blocks of nucleic acids and essential for many cellular functions. In this study, ultrasonic absorption spectra of $\beta$-cyclodextrin ($\beta$-CD) and adenosine 5'-monophosphate (AMP) in aqueous solution were measured over the broad frequency range 0.1-40 MHz with emphasis on the low-frequency range below 1 MHz. Here we show that the interaction of $\beta$-CD and AMP complies with a typical spectrum of a single relaxation process. We determined reliable rate (kb) and equilibrium (K) constants and a standard volume change ($\Delta$V) of the reaction. They are $k_b=2.3{\times}{{10^{-6}}_s}^{-1},\;K=89M^{-1},\;and\;{\Delta}V=13.8(10^{-6}m^3mol^{-1})$, respectively.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권1호
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• pp.37-41
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• 2001

HPLC separation of ionic samples tends to be more complicated and difficult to understand than that of non-ionic compounds. On the other hand, band spacing is much more easily manipulated for ionic than for neutral samples. Ion-suppression RP-HPLC method was used with organic modifier and aqueous buffer solution. In this work, five mononucleotides of cytidine-5-monophosphate (5-CMP) disodium salt, uridine-5-monophosphate disodium salt (5-UMP), guanosine-5-monophosphate disodium salt (5-GMP), inosine-5-monophosphate disodium salt (5-IMP), and adenosine-5-monophosphate disodium salt (5-AMP) were examined. Acetic acid and sodium phosphate were used as buffers, and methanol as an organic modifier. A new relationship between the retention factor and the buffer concentration at a fixed modifier content (5% of methanol) could be expressed by following: K = (k(sub)-1 + k(sub)0 (k(sub)B/k(sub)S)/(1 + (k(sub)B/k(sub)S) C(sub)B(sup)a), where C(sub)B was the concentration of buffer. Using this relationship, the calculated values closely matched the experimental data. The derived relationship showed that as the buffer concentration increased, the retention factor approached a certain value, and this was buffer dependent.