• Biomedical Science Letters
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• v.10 no.2
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• pp.99-105
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• 2004

Liver and serum rhodanese activities were determined in acute ethanol intoxicated rats with extrahepatic cholestasis induced by common bile duct ligation (CBD) to manifest the biochemical background of alcohol drinking hazard under the hepatobiliary disease. Liver cytosolic and microsomal rhodanese activities and these Vmax values in CBD ligated rats with acute ethanol intoxication were found to be decreased much more than that in CBD ligation alone. However, the difference of Km value on above hepatic enzyme was not found between the experimental groups. On the other hand, serum rhodanese activity in CBD ligated rats with acute ethanol intoxication was greater increased more than that in CBD ligation alone. These results indicate that the biosynthesis of the hepatic rhodanese decreases and the serum rhodanese activity increases in cholestasis combined with acute ethanol intoxication, reflecting damage of aggravated hapatocytic membrane. Accordingly, the resulting data supported the fact that alcoholic drinks were enzymologically harmful to the hepatobiliary disease.

• BMB Reports
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• v.28 no.2
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• pp.170-176
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• 1995

Rhodanese from mouse liver was purified to near homogeneity by ammonium sulfate precipitation, CM-Sephadex ion exchange, hydroxyapatite and Sephacryl S-200-HR gel filtration chromatographies with a purification of 776 folds. The molecular weight was determined by Sephadex G-150 gel filtration and found to be 34.8 KDa. SOS-PAGE showed molecular weight 34 KDa and two identical subunits splitting by aging for 3 weeks at $-70^{\circ}C$ the molecular weight of which was 17 KDa. The optimal pH of enzyme activity was 9.4 and the pI value of the enzyme was 6.6. Rhodanese showed the optimal reaction temperature of $25^{\circ}C$ and near linear increasing pattern until 10 min. incubation. $K_m$ values of rhodanese for KCN and $Na_{2}S_{2}O_{3}$ as substrates were 12.5 mM and 8.3 mM, respectively. Rhodanese activity was inhibited by more than 70% at a concentration of 100 ${\mu}M$ of $Ni^{2+}$, $Zn^{2+}$, $Cd^{2+}$, $Hg^{2+}$ and $Cu^{2+}$. Other metal ions, such as $Mn^{2+}$, $Mg^{2-}$, $Ca^{2+}$, and $Fe^{2+}$ showed no effect on rhodanese activity.

• Toxicological Research
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• v.25 no.1
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• pp.23-28
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• 2009

Some of the edible plants like apricot kernel, flaxseed, and cassava generate hydrogen cyanide (HCN) when cyanogenic glycosides are hydrolyzed. Rhodanese (thiosulfate: cyanide sulfurtransferases of TSTs; EC: 2.8.1.1) is a sulfide-detoxifying enzymes that converts cyanides into thiocyanate and sulfite. This enzyme exists in a liver and kidneys in abundance. The present study is to evaluate the conversion of apricot cyanogenic glycosides into thiocyanate by human hepatic (HepG2) and colonal (HT-29) cells, and the induction of the enzymes in the rat. The effects of short term exposure of amygdalin to rats have also been investigated. Cytosolic, mitochondrial, and microsomal fractions from HepG2 and HT-29 cells and normal male Spraque-Dawley rats were used. When apricot kernel extract was used as substrate, the rhodanese activity in liver cells was higher than the activity in colon cells, both from established human cell line or animal tissue. The cytosolic fractions showed the highest rhodanese activity in all of the cells, exhibiting two to three times that of microsomal fractions. Moreover, the cell homogenates could metabolize apricot extract to thiocyanate suggesting cellular hydrolysis of cyanogenic glycoside to cyanide ion, followed by a sulfur transfer to thiocyanate. After the consumption of amygdalin for 14 days, growth of rats began to decrease relative to that of the control group though a significant change in thyroid has not been observed. The resulting data support the conversion to thiocyanate, which relate to the thyroid dysfunction caused by the chronic dietary intake of cyanide. Because Korean eats a lot of Brassicaceae vegetables such as Chinese cabbage and radish, the results of this study might indicate the involvement of rhodanese in prolonged exposure of cyanogenic glycosides.

• BMB Reports
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• v.37 no.3
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• pp.275-281
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• 2004

Rhodanese was isolated and purified from the cytosolic fraction of liver tissue homogenate of the fruit bat, Eidolon helvum, by using ammonium sulphate precipitation and CM-Sephadex C-50 ion exchange chromatography. The specific activity was increased 130-fold with a 53% recovery. The $K_m$ values for KCN and $Na_2S_2O_3$ as substrates were $13.5{\pm}2.2\;mM$ and $19.5{\pm}0.7\;mM$, respectively. The apparent molecular weight was estimated by gel filtration on a Sephadex G-100 column to be 36,000 Da. The optimal activity was found at a high pH (pH 9.0) and the temperature optimum was $35^{\circ}C$. An Arrhenius plot of the heat stability data consisted of two linear segments with a break occurring at $35^{\circ}C$. The apparent activation energy values from these slopes were 11.5 kcal/mol and 76.6 kcal/mol. Inhibition studies on the enzyme with a number of cations showed that $Mg^{2+}$, $Mn^{2+}$, $Ca^{2+}$, and $Co^{2+}$ did not affect the activity of the enzyme, but $Hg^{2+}$ and $Ba^{2+}$ inhibited the enzyme.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2261-2265
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• 2007

Prevention of thermal aggregation of the denatured protein by the group II chaperonin from the aerobic hyperthermophilic crenarchaeon Aeropyrum pernix K1 (ApcpnA) has been investigated. ApcpnA exists as a homo-oligomer in a ring structure, which protects thermal aggregation of the chemically denatured bovine rhodanese at 50 oC. ApcpnA alone is not sufficient for chaperonin activity, but the chaperonin activity is greatly enhanced in the presence of manganese ion and ATP. Compared to the mesophilic chaperonin GroEL/GroES, ApcpnA is more activated at a higher temperature and protects the aggregation-prone unfolded state of the denatured rhodanese from thermal aggregation. Binding of ATP is sufficient for ApcpnA to perform the chaperonin function in vitro, but hydrolysis of ATP is not necessarily required. We propose that utilization of Mn2+ and adenosine nucleotide regardless of ATP hydrolysis may be one of peculiar properties of archaeal chaperonins.

• Journal of Microbiology and Biotechnology
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• v.19 no.1
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• pp.17-22
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• 2009

The mixotrophic growth with methanol plus thiosulfate was examined in nutrient-limited mixotrophic condition for Methylobacterium goesingense CBMB5 and Methylobacterium fujisawaense CBMB37. Thiosulfate oxidation increased the growth and protein yield in mixotrophic medium that contained 150mM methanol and 20mM sodium thiosulfate, at 144 h. Respirometric study revealed that thiosulfate was the most preferable reduced inorganic sulfur source, followed by sulfite and sulfur. M. goesingense CBMB5 and M. fujisawaense CBMB37 oxidized thiosulfate directly to sulfate, and intermediate products of thiosulfate oxidation such as polythionates, sulfite, and sulfur were not detected in spent medium and they did not yield positive amplification for tested soxB primers. Enzymes of thiosulfate oxidation such as rhodanese and sulfite oxidase activities were detected in cell-free extracts of M. goesingense CBMB5, and M. fujisawaense CBMB37, and thiosulfate oxidase (tetrathionate synthase) activity was not observed. It indicated that both the organisms use the "non-S4 intermediate" sulfur oxidation pathway for thiosulfate oxidation. It is concluded from this study that M. goesingense CBMB5, and M. fujisawaense CBMB37 exhibited mixotrophic metabolism in medium containing methanol plus thiosulfate and that thiosulfate oxidation and the presence of a "Paracoccus sulfur oxidation" (PSO) pathway in methylotrophic bacteria are species dependant.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.392-399
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• 2014

Plant senescence is one of the survival strategies to use limited nutrients efficiently during growth, development and adaptation. In this study, we isolated a gene (PagSEN1) homologous to SENESCENCE 1 from Populus alba ${\times}$ P. glandulosa. The PagSEN1 gene encodes a putative protein consisting of 243 amino acids containing a rhodanese domain. Southern blot analysis suggested that two copies of the PagSEN1 gene are present in the poplar genome. We characterized its transcriptional expression under various conditions mimicking senescence and environmental stresses. The PagSEN1 was expressed most strongly in mature leaves but most weakly in roots. The gene was significantly up-regulated by treatments with mannitol, NaCl, ABA and JA, but not by cold, SA and GA3. These results indicate that PagSEN1 is involved in senescence response induced by environmental stresses.

• Genomics & Informatics
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• v.18 no.3
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• pp.28.1-28.9
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• 2020

Streptomyces coelicolor is a gram-positive soil bacterium which is well known for the production of several antibiotics used in various biotechnological applications. But numerous proteins from its genome are considered hypothetical proteins. Therefore, the present study aimed to reveal the functions of a hypothetical protein from the genome of S. coelicolor. Several bioinformatics tools were employed to predict the structure and function of this protein. Sequence similarity was searched through the available bioinformatics databases to find out the homologous protein. The secondary and tertiary structure were predicted and further validated with quality assessment tools. Furthermore, the active site and the interacting proteins were also explored with the utilization of CASTp and STRING server. The hypothetical protein showed the important biological activity having with two functional domain including POD-like_MBL-fold and rhodanese homology domain. The functional annotation exposed that the selected hypothetical protein could show the hydrolase activity. Furthermore, protein-protein interactions of selected hypothetical protein revealed several functional partners those have the significant role for the bacterial survival. At last, the current study depicts that the annotated hypothetical protein is linked with hydrolase activity which might be of great interest to the further research in bacterial genetics.