• Archives of Pharmacal Research
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• v.20 no.2
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• pp.158-170
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• 1997

New HMG-CoA reductase inhibitors, in which 3-substituted 4, 5-polymethylenepyrazoles are employed as a hydrophobic anchor connected to tetrahydro-4-hydroxy-2H-pyran-2-one by a two-carbon bridge, were designed and synthesized to exhibit significant inhibitory activity comparable to mevinolin. The most potent enzyme inhibitor $(11cc, IC_{50}=0.01{\mu}M)$ is 4-fold more potent than lovastatin.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.414-421
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• 1999

Helicobacter pylori were found to be resistant to azide but sensitive to vanadate, suggesting that defect in the P-type ATPase activity rather than F-type ATPase would be lethal to cell survival or growth. To elucidate the relationship between this enzyme inhibition and H. pylori death, we determined the effect of omeprazole (OMP) plus vanadate on enzyme activity and cell growth. The minimum inhibitory concentration (MIC; ca. 0.8$\mu$mol/disk) of vanadate for H. pylori growth was lowered over l0-fold with the aid of OMP, whereby its inhibitory potential toward the P-type ATPase activity was diametrically increased. Alternatively, we found that this enzyme activity was essential for active transport in H. pylori. From these observations, we strongly suggest that the immediate cause of the growth inhibition of H. pylori cells with OMP and/or vanadate might be defective in the cell's active transport due to the lack of P-type ATPase activity. From the spectral data with circular dichroism (CD) spectroscopy, we found that activated OMP (OAS) at concentration below MIC did not disrupt helical structures of membrane proteins. Separately, we determined the cytopathic effect of OAS by SDS-PAGE, indicating the change in the production of cytoplasmic protein but not cell membrane.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.339-342
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• 2012

This study describes the characterization of a new angiotensin I-converting enzyme (ACE) inhibitory peptide from a Korean traditional rice wine. After purification of the ACE inhibitor peptides with ultrafiltration, Sephadex G-25 column chromatography, and successively $C_{18}$ and SCX solid-phase extraction, reverse-phase HPLC, and size exculsion chromatography, two types of the purified ACE inhibitors with $IC_{50}$ values of 0.34 mg/ml and 1.23 mg/ml were finally obtained. The two purified ACE inhibitors (F-1 and F-2) were found to have two kinds of novel oligopeptides, showing very little similarity to other ACE inhibitory peptide sequences. The amino acid sequences of the two purified oligopeptides were found to be Gln-Phe-Tyr-Ala-Val (F-1) and Ala-Gly-Pro-Val-Leu-Leu (F-2), and their molecular masses were estimated to be 468.7 Da (F-1) and 357.7 Da (F-2), respectively. They all showed a clear antihypertensive effect on spontaneously hypertensive rats at a dosage of 500 mg/kg.

• Journal of IKEEE
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• v.21 no.3
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• pp.309-319
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• 2017

The research investigates the inhibition of fatty acid biosynthesis of the human Acetyl-CoA Carboxylase enzyme by the aromatic-structure inhibitors (also known as ligands) containing variables of substituents, contributing an important role in the treatment of fatty-acid metabolic syndrome expressed by the group of cardiovascular risk factors increasing the incidence of coronary heart disease and type-2 diabetes. The effective interoperability between ligand and enzyme is characterized by a 50% concentration of enzyme inhibitor ($IC_{50}$) which was determined by experiment, and the factor of geometry structure of the ligands which are modeled by quantum mechanical methods using HyperChem 8.0.10 and Gaussian 09W softwares, combining with the calculation of quantum chemical and chemico-physical structural parameters using HyperChem 8.0.10 and Padel Descriptor 2.21 softwares. The result data are processed with the combination of classical statistical methods and modern bioinformatics methods using the statistical softwares of Department of Pharmaceutical Technology - Jadavpur University - India and R v3.3.1 software in order to accomplish a model of the quantitative structure - activity relationship between aromatic-structure ligands inhibiting fatty acid biosynthesis of the human Acetyl-CoA Carboxylase.

• Korean Journal of Microbiology
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• v.29 no.6
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• pp.345-352
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• 1991

A serine proteinase of molecular weight 60 kd was purified from culture supernatant of P. aeruginosa using DEAE-Trisacryl M ion-exchange and AcA 54 gel filtration column chromatography, and the properties of serine proteinase were characterized. By means of SDS-polyacrylamide gel electrophoresis, the molecular weight of the enzyme was 55 kd. The optimal pH for the activity of purified enzyme was 7.5. The activity of the purified enzyme was completely inhibited by Di-isopropylfluorophosphate(DFP) and N-.alpha.-p-tosyl-L-lysine choloromethyl detone(TLCK) but not by other proteinase inhibitors such as E-64, pepstatin A, 1, 10-phenanthroline. The purified enzyme was capable of degrading type I and type IV collagen. Antisera obtained from hymans infected with Pseudomonas aeruginosa reacted to the purified serine proteinase in immunoblots. These results indicate that the purified enzyme is trypsin-like serine proteinase and this enzyme of P. aeruginosa may play an important role in tissue damage as a spreading factor and may be useful for serodiagnosis of Pseudomonas infections.

• Archives of Pharmacal Research
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• v.20 no.6
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• pp.519-524
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• 1997

Steroid $9{\alpha}$-hydroxylase is an enzyme found in nocardioform microorganisms which can utilize steroids as a sole carbon source. After fractional centrifugation of the cell homogenates, the enzyme activity in Nocardia and Rhodococcus was found in cytoplasmic membrane fraction. On the contrary, Mycobacterium had its 9.alpha.-hydroxylation activity in cytosolic fraction. To characterize the enzyme in these microorganisms, several potential inhibitors of 9.alpha.-hydroxylase were tested and the cofactor requirement for the same enzyme was also examined. The inhibitory effect of ferrous ion chelators indicated involvement of iron containing proteins in the 9.alpha.-hydroxylase system. On the other hand, metyrapone, an inhibitor known to be specific for cytochrome P450 interfered with the enzyme in Mycobacterium, but didn't inhibit the enzyme activity in Nocardia and Rhodococcus. While the $9{\alpha}$-hydroxylase system in Nocardia and Rhodococcus required NADPH, NADH was required as an election donor in Mycobacterium.

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.81-88
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• 2012

Histone deacetylases (HDACs) are enzymes involved in the remodelling of chromatin, and have a key role in the epigenetic regulation of gene expression. Histone deacetylase (HDAC) inhibitors are emerging as an exciting new class of potential anti-cancer agents. In recent years, a number of structurally diverse HDAC inhibitors have been identifi ed and these HDAC inhibitors induce growth arrest, differentiation and/or apoptosis of cancer cells in vitro and in vivo. However, the underlying molecular mechanisms remain unclear. This study aimed at investigating the anti-tumor activity of various HDAC inhibitors, IN-2001, using T47D human breast cancer cells. Moreover, the possible mechanism by which HDAC inhibitors exhibit anti-tumor activity was also explored. In estrogen receptor positive T47D cells, IN-2001, HDAC inhibitor showed anti-proliferative effects in dose-and time-dependent manner. In T47D human breast cancer cells showed anti-tumor activity of IN-2001 and the growth inhibitory effects of IN-2001 were related to the cell cycle arrest and induction of apoptosis. Flow cytometry studies revealed that IN-2001 showed accumulation of cells at $G_2$/M phase. At the same time, IN-2001 treatment time-dependently increased sub-$G_1$ population, representing apoptotic cells. IN-2001-mediated cell cycle arrest was associated with induction of cdk inhibitor expression. In T47D cells, IN-2001 as well as other HDAC inhibitors treatment significantly increased $p21^{WAF1}$ and $p27^{KIP1}$ expression. In addition, thymidylate synthase, an essential enzyme for DNA replication and repair, was down-regulated by IN-2001 and other HDAC inhibitors in the T47D human breast cancer cells. In summary, IN-2001 with a higher potency than other HDAC inhibitors induced growth inhibition, cell cycle arrest, and eventual apoptosis in human breast cancer possibly through modulation of cell cycle and apoptosis regulatory proteins, such as cdk inhibitors, cyclins, and thymidylate synthase.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1582-1589
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• 2009

Bacterial UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) catalyzes the transfer of enolpyruvate from phosphoenolpyruvate (PEP) to uridine diphospho-N-acetylglucosamine (UNAG), which is the first step of bacterial cell wall synthesis. We identified thimerosal, thiram, and ebselen as effective inhibitors of Haemophilus influenzae MurA by screening a chemical library that consisted of a wide range of bioactive compounds. When MurA was preincubated with these inhibitors, their 50% inhibitory concentrations ($IC_{50}s$) were found to range from 0.1 to $0.7\;{\mu}M$. In particular, thimerosal suppressed the growth of several different Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhimurium at a concentration range of $1-2\;{\mu}g/ml$. These inhibitors covalently modified the cysteine residue near the active site of MurA. This modification changed the open conformation of MurA to a more closed configuration, which may have prevented the necessary conformational change from occurring during the enzyme reaction.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2004.11a
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• pp.210-218
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• 2004

Poly(ADP-ribose)polymerase-1 (PARP-1) is a nuclear enzyme involved in various physical functions related to genomic repair, and PARP inhibitors have therapeutic application in a variety of neurological diseases. Docking and the QSAR (quantitative structure-activity relationships) studies for 52 PARP-1 inhibitors were conducted using FlexX algorithm, comparative molecular field analysis (CoMFA), and hologram quantitative structure-activity relationship analysis (HQSAR). The resultant FlexX model showed a reasonable correlation (r$^{2}$ = 0.701) between predicted activity and observed activity. Partial least squares analysis produced statistically significant models with q$^{2}$ values of 0.795 (SDEP=0.690, r$^{2}$=0.940, s=0.367) and 0.796 (SDEP=0.678, r$^{2}$ = 0.919, s=0.427) for CoMFA and HQSAR, respectively. The models for the entire inhibitor set were validated by prediction test and scrambling in both QSAR methods. In this work, combination of docking, CoMFA with 3D descriptors and HQSAR based on molecular fragments provided an improved understanding in the interaction between the inhibitors and the PARP. This can be utilized for virtual screening to design novel PARP-1 inhibitors.

• The Korean Journal of Pesticide Science
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• v.5 no.3
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• pp.41-46
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• 2001

This study was conducted to develop a high throughput system for screening acetolactate synthase(ALS) inhibitors, and to detect basic mother molecules for developing new novel herbicide candidates. The high throughput screening (HTS) method using 96-well plate and microplate reader was developed. This method is 8 times more effective than basic technique in one cycle per person. Futhermore, considering for less than 1/10 volume of materials required for ALS test and enzyme kinetics with 16 times faster speed compared to those of former procedure, this HTS method has more than 100 times higher efficacy than basic system in a consecutive procedure. We discovered 11 new ALS inhibitors such as 2-oxoglutaric acid, aminooxyacetic acid, azelaic acid, citric acid, cyanuric fluoride, itaconic acid, malonic acid, niclosamide, oxalic acid, glyoxylic acid, and suramin from 107 commercial plant-specific inhibitors using this technique. We hope these results might be useful to discover lead compounds for developing new novel herbicide candidate.