• BMB Reports
• /
• v.30 no.6
• /
• pp.397-402
• /
• 1997

A thiol-specific spin label was attached to cysteine-102 of yeast cytochrome c and electron paramagnetic resonance (EPR) spectra were measured as a function of added cytochrome c oxidase concentration. The intensity decreased due to line broadening as cytochrome c formed a complex with cytochrome c oxidase and reached a minimum when the ratio of cytochrome c to cytochrome c oxidase became one. Replacement of either Lys-72 or Lys-87 of cytochrome c by Glu did not result in a significant change in binding affinity. Interestingly the K72E mutant, unlike K87E, had a much lower rate of electron transfer than the wild type. These results indicate that many positively charged residues as a group participate in complex formation but Lys-72 might be important for cytochrome c to be locked in an orientation for an efficient electron transfer. A stoichiometry of 1 was also confirmed by optical absorption of the cytochrome c-cytochrome c oxidase complex which had been run through a gel chromatography cloumn to remove unbound cytochrome c. The EPR spectrum of this 1:1 complex, however, was a mixture of two components. This explains a biphasic kinetics for a single binding site on cytochrome c oxidase without invoking conformational transition.

• Microbiology and Biotechnology Letters
• /
• v.47 no.4
• /
• pp.487-497
• /
• 2019

Fetal Bovine Serum (FBS) is an essential substance added to animal cell culture medium. However, its composition is unclear causing problems such as development of an immune response when cultured cells are transplanted into the human body. In this study, silk sericin, silk fibroin, and hemolymph obtained from silkworms were added to the cell culture medium in order to determine if it can replace FBS. After establishment of the cell culture, cell proliferation and expression levels of cell growth-related genes were compared with those of control cells (cells cultured in the medium with 10% FBS). Results showed that the test group treated with silk fibroin extracted from a Korean silkworm variety, Kumokjam could replace 10% FBS. In addition, expression levels of cell growth related genes such as Fibronectin and TGF-β1 increased significantly in cells cultured using silk fibroin, depending on the concentration used in cell adhesion and cell proliferation [24]. To date, no studies have been conducted to find a replacement for FBS. Thus, this study was carried out to develop a substitute for FBS by using silkworm-derived alternatives such as silkworm hemolymph, silk sericin, and silk fibroin, which are cheap and have various physiological effects, cell promoting effects, and can be mass produced.

• Analytical Science and Technology
• /
• v.10 no.5
• /
• pp.378-385
• /
• 1997

In order to clarify the functional role of Tyr7 in human glutathione S-transferase P1-1, we extensively investigated the effect of mutation of Tyr7 on the substrate specificity and inhibition characteristics. The mutational replacement of Tyr7 with phenylalanine lowered the specific activities with 1,2-dichloro-4-nitrobenzene and 1,2-epoxy-3-(p-nitrophenoxy) propane for GSH-conjugation reaction to 3~5% of the values for the wild-type enzyme. The pKa of the thiol group of GSH bound in Y7F was about 2.4 pK units higher than that in the wild-type enzyme. The $I_{50}$ of hematin for Y7F was similar to that for the wild-type enzyme and those of benastatin A and S-(2,4-dinitrophenyl)glutathione were only moderately decreased. These results suggest that Tyr7 is considered to be important the catalytic activities not only for GSH-chloronitrobenzene derivatives but also for GSH-epoxide conjugation reaction, rather than to binding of the substrates.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.7
• /
• pp.1113-1125
• /
• 2020

Objective: This study was investigated the effects of dietary supplementation of Antrodia cinnamomea fermented product on modulation of antioxidation, anti-inflammation, and lipid metabolism in broilers. Methods: Functional compounds and in vitro antioxidant capacity were detected in wheat bran (WB) solid-state fermented by Antrodia cinnamomea for 16 days (FAC). In animal experiment, 400 d-old broiler chickens were allotted into 5 groups fed control diet, and control diet replaced with 5% WB, 10% WB, 5% FAC, and 10% FAC respectively. Growth performance, intestinal microflora, serum antioxidant enzymes and fatty acid profiles in pectoral superficial muscle were measured. Results: Pretreatment with hot water extracted fermented product significantly reduced chicken peripheral blood mononuclear cells death induced by lipopolysaccharide and 2,2'-Azobis(2-amidinopropane) dihydrochloride. Birds received 5% and 10% FAC had higher weight gain than WB groups. Cecal coliform and lactic acid bacteria were diminished and increased respectively while diet replaced with FAC. For FAC supplemented groups, superoxide dismutase (SOD) activity increased at 35 days only, with catalase elevated at 21 and 35 day. Regarding serum lipid parameters, 10% FAC replacement significantly reduced triglyceride and low-density lipoprotein level in chickens. For fatty acid composition in pectoral superficial muscle of 35-d-old chickens, 5% and 10% FAC inclusion had birds with significantly lower saturated fatty acids as compared with 10% WB group. Birds on the 5% FAC diet had a higher degree of unsaturation, followed by 10% FAC, control, 5% WB, and 10% WB. Conclusion: In conclusion, desirable intestinal microflora in chickens obtaining FAC may be attributed to the functional metabolites detected in final fermented product. Moreover, antioxidant effects observed in FAC were plausibly exerted in terms of improved antioxidant enzymes activities, increased unsaturated degree of fatty acids in chicken muscle and better weight gain in FAC inclusion groups, indicating that FAC possesses promising favorable mechanisms worthy to be developed.

• Clinical and Experimental Pediatrics
• /
• v.55 no.2
• /
• pp.48-53
• /
• 2012

Purpose: Gaucher disease is caused by a ${\beta}$-glucocerebrosidase (GBA) deficiency. The aim of this study is to investigate the clinical and genetic characteristics according to subtypes of Gaucher disease in the Korean population. Methods: Clinical findings at diagnosis, $GBA$ mutations, and clinical courses were reviewed in 20 patients diagnosed with Gaucher disease. Results: Eleven patients were diagnosed with non-neuronopathic type, 2 with acute neuronopathic type, and 7 with chronic neuronopathic type. Most patients presented with hepatosplenomegaly, thrombocytopenia, and short stature. In the neuronopathic group, variable neurological features, such as seizure, tremor, gaze palsy, and hypotonia, were noted at age $8.7{\pm}4.3$ years. B cell lymphoma, protein-losing enteropathy, and hydrops fetalis were the atypical manifestations. Biomarkers, including chitotriosidase, acid phosphatase, and angiotensin-converting enzyme, increased at the initial evaluation and subsequently decreased with enzyme replacement treatment (ERT). The clinical findings, including hepatosplenomegaly, thrombocytopenia, and skeletal findings, improved following ERT, except for the neurological manifestations. L444P was the most common mutation in our cohort. One novel mutation, R277C, was found. Conclusion: Although the clinical outcome for Gaucher disease improved remarkably following ERT, the outcome differed according to subtype. Considering the high proportion of the neuronopathic form in the Korean population, new therapeutic strategies targeting the central nervous system are needed, with the development of a new scoring system and biomarkers representing clinical courses in a more comprehensive manner.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.2
• /
• pp.296-301
• /
• 2015

Chronic kidney diseases are based on uncontrolled immunological and inflammatory responses to pathophysiological renal circumstances such as glomerulonephritis, which is caused by immunological mechanisms of glomerular inflammation with increased production of renal pro-inflammatory cytokines. Pentoxifylline (PTX) exhibits anti-inflammatory properties by inhibiting cytokine and chemokine production through aggregation of erythrocytes and thrombocytes. We synthesized a series of 1,7-substituted methylxanthine derivatives by the Traube purine reaction, and the formation of purine ring was completed through nitrosation, a reduction of the nitroso to the amine by catalytic hydrogenation as derivatives of PTX. Then we studied biological activities such as renal anti-inflammatory effects of the synthesized compounds in the production of cytokines such as nitric oxide (NO), interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) and of chemokines such as monocyte chemoattractant protein-1 and IL-8 in Raw 264.7 and HK-2 cells. Renal antiinflammatory activities of this novel series of N-1 and N-7-substituted methylxanthine showed that the N-7 methyl-group-substituted analogs (S7b) showed selective 61% and 77% inhibition of the production of NO and IL-8. The other replacement of the N-1-(CH₂)₄COCH₃ roup, as in the case of compound S6c, also showed an effective 50% and 77% inhibition of TNF-α and IL-8 production in LPS-stimulated Raw 264.7 and HK-2 cells.

• Microbiology and Biotechnology Letters
• /
• v.48 no.3
• /
• pp.373-382
• /
• 2020

Candidatus Carsonella ruddii is an endosymbiont that resides in specialized cells within the body cavity of plant sap-feeding insects called psyllids. The establishment of symbiotic associations is considered one of the key factors for the evolutionary success of psyllids, as it may have helped them adapt to imbalanced food resources like plant sap. Although C. ruddii is defined as a psyllid primary symbiont, the genes for some essential amino acid pathways are absent. Complete genome sequences of several C. ruddii strains have been published. However, in-depth intra-species comparison of C. ruddii strains has not yet been done. This study therefore aimed to perform a comparative genome analysis of six C. ruddii strains, allowing the interrogation of phylogenetic group, functional category of genes, and biosynthetic pathway analysis. Accordingly, overall genome size, number of genes, and GC content of C. ruddii strains were reduced. Phylogenetic analysis based on the whole genome proteomes of 30 related bacterial strains revealed that the six C. ruddii strains form a cluster in same clade. Biosynthetic pathway analysis showed that complete sets of genes for biosynthesis of essential amino acids, except tryptophan, are absent in six C. ruddii strains. All genes for tryptophan biosynthesis are present in three C. ruddii strains (BC, BT, and YCCR). It is likely that the host may depend on a secondary symbiont to complement its deficient diet. Overall, it is therefore possible that C. ruddii is being driven to extinction and replacement by new symbionts.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.7
• /
• pp.789-798
• /
• 2016

In this paper, we propose a cache algorithm based on user's context for enterprise/urban smallcell environments. The smallcell caching method is to store mobile users' data traffic at a storage which is equipped in smallcell base station and it has an effect of reducing core networks traffic volume. In our algorithm, contrary to existing smallcell cache algorithms, the cache storage is equipped in a edge server by using a concept of the Mobile Edge Computing. In order to reflect user's characteristics, the edge server classifies users into several groups based on user's context. Also the edge server changes the storage size and the cache replacement frequency of each group to improve the cache efficiency. As the result of performance evaluation, the proposed algorithm can improve the cache hit ratio by about 11% and cache efficiency by about 5.5% compared to the existing cache algorithm.

• Macromolecular Research
• /
• v.14 no.2
• /
• pp.179-186
• /
• 2006

In the present work, low density polyethylene (LDPE)/aliphatic polyester (APES)/organoclay ternary nanocomposites were prepared. In particular, the effect of a compatibilizer, polyethylene-graft-maleic anhydride (PE-g-MAH), on the morphology and properties of the ternary nanocomposites was investigated. LDPE/APES/organoclay nanocomposites were prepared through melt intercalation method using two different kinds of organoclay. The dispersibility of silicate clays in the nanocomposites was investigated by X-ray diffraction and atomic force microscopy. The ternary nanocomposites showed higher tensile properties than the LDPE/APES blend did. The dispersibility and properties of nanocomposites containing Cloisite 30B were better than those of the nanocomposites containing Cloisite 20A. Unlike Cloisite 20A, hydroxyl groups in the intercalants in Cloisite 30B interlayer underwent a certain polar interaction with the carboxyl group of APES, favoring the intercalation of APES chains and the formation of LDPE/APES/Closite 30B nanocomposites. However, the introduction of the polar hydroxyl groups also enhanced the interaction with the silicate surface at the same time, thereby rendering somewhat difficult the replacement of the surface contacts by LDPE chains, and impeding the extensive intercalation and further exfoliation of Cloisite 30B in the LDPE/APES matrix. The compatibilizer enhanced the intercalation of the polymer chain inside the clay gallery and thus improved the mechanical properties of the ternary nanocomposites. Rheological measurements of the nanocomposites via frequency sweep experiment indicated a certain interaction between the clay platelet and the polymer molecules in the melted state.

• International Commerce and Information Review
• /
• v.9 no.1
• /
• pp.381-399
• /
• 2007

UCP 600 will now come into effect on 1 July 2007, giving practitioners more than six months to prepare for the change. The vote on the UCP was also a favourable vote on eUCP Version 1.1 which was amended to bring it into conformity with the new rules. ICC Banking commission unanimeusly approved the revised UCP 600 on 26 October 2006 in paris convention. The most important revision of UCP600 have altered the technical and difficult to understand wording of UCP500 into plain simple precise and concise language, The singuler achievement of UCP600 is its elimination of phrase like "reasonable care" "reasonable time" and "an it's face" from the rule. The introduction of separate articles 2 and 3 on "Definitions" and "Interpretation" which contain the concept of "honour" along with the inclusion of certain ISBP wording in UCP, should bring about far greater clarity and precision than in many of the contentions articles in UCP500. The definition of negotiation should help lay to rest the controversies surrounding the terms of negotiation. The removal of reasonable time and the replacement by five banking days should speed the process and make L/Cs more attractive in the market, nevertheless UCP600 have many problems in appling it in practical field. For example the definition of credit, negotiation and purchase it's accepted or undertaken payment draft by accepting bank or deferred payment bank, the second advising bark's position etc. so, I will introduce in this thesis the important revised articles of UCP600 and investigate the problems in applying it in practicle field with reference to the specialist's opinion of the practical field and ICC opinions of drafting Group.