• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2079-2082
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• 2004

This paper study on OLEDs(Organic Light Emitting Diodes) panel using PLD(Pulsed Laser Deposition) methode. Deposition of organic was used Q-stitched Nd/YAG laser in 355 nm and reduced organic pellet for PLD method. Organic morphology was measured AFM(Atomic Forced Microscope) and emitting efficiency was measured luminance meter.

• KSBB Journal
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• v.10 no.1
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• pp.30-37
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• 1995

Membrane-bound alcohol dehydrogenase(ADH) was purified to homogeneity from the acetic acid producing bacteria, Acetobacter sp. KM. The enzyme was solubilized and extracted with Triton X-100 and purified using the Mono-Q ion exchange chromatography and Superose 12 gel filtration chromatography. The enzyme was purified to 12-fold with a yield of 30%. The molecular weight of the purified enzyme was to be 335 KDa. SDS-PAGE of the enzyme showed two subunits with molecular weights of 79 KDa and 49 KDa. It indicated that the enzyme consisted of three subunits of the 79 KDa and two subunits of the 49 KDa. The purified .ADH preferentially oxidized straight chain aliphatic alcohol except methanol. Formaldehyde, acetaldehyde and glutaraldehyde were also oxidized. The apparent Km for ethanol was 1.04 mM and the optimum pH and temperature were 5.0∼6.0 and 32$^{\circ}C$, respectively. V2O5 and divalent cation such as ZnCl2 and NiCl2 inhibited enzymatic activity.

• BMB Reports
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• v.31 no.3
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• pp.240-244
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• 1998

Helicobacter pylori is the etiologic agent of human gastritis and peptic ulceration and produces urease as the major protein component on its surface. H. pylori urease is known to serve as a major virulence factor and in a potent immunogen. In order to express the recombinant urease at a higher level, a DNA fragment containing the minimal H. pylori urease gene cluster was subcloned into a high copy-number vector. The recombinant H. pylori urease expressed in an E. coli strain that was grown in a rich medium supplemented with added nickel was purified to near homogeneity by using DEAE-Sepharose, Superdex HR200, and Mono-Q (FPLC) columns and the purified enzyme possessed the specific activity of 1255 U/mg. Polyclonal antibodies raised against the purified recombinant H. pylori urease were shown to be very specific when subjected to Western blot analysis, in which crude extracts from the H. pylori ATCC strain and the recombinant E. coli strains expressing various bacterial ureases were exnmined for cross-reactivity.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.26-29
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• 1996

The genes coding for the urease of alkalophilic Bacillus pasteurii have been previously cloned and recently sequenced. (You, J. H., B. H. Song, J. H. Kim, M. H. Lee, and S. D. Kim (1995) Molecules and Cells 5, 359-369.) The recombinant Bacillus pasteurii urease expressed in an E. coli HB101 strain was purified 31.2 fold by using combinations of anion-exchange and hydrophobic chromatography followed by Mono-Q chromatography on a FPLC. In spite of the presence of three discrete structural peptide genes in the Bacillus pasteurii urease gene cluster, only one or two enzyme subunits have been observed to date. Here we report for the first time that the recombinant Bacillus pasteurii urease expressed in a E. coli strain consists of three distinct subunits. One large subunit was estimated to be of $M_r$=65, 200 and the two small-subunit peptides are of $M_r$=14, 500 and $M_r$=13, 700, respectively.

• Parasites, Hosts and Diseases
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• v.43 no.4 s.136
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• pp.157-160
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• 2005

A 29kDa cysteine protease of Taenia solium metacestodes was purified by Mono Q anion-exchanger and Superose 6 HR gel filtration chromatography. The enzyme was effectively inhibited by cysteine protease inhibitors, such as iodoacetic acid (IAA) and trans-epoxy-succinyl-L-leucyl-amido (4-guanidino) butane (E-64) while inhibitors acting on serine- or metallo-proteases did not affect the enzyme activity. The purified enzyme degraded human immunoglobulin G (IgG), collagen and bovine serum albumin (BSA), but human IgG was more susceptible for proteolysis by the enzyme. To define the precise biological roles of the enzyme, more detailed biochemical and functional studies would be required.

• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.316-321
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• 2000

Role of enterotoxin from Salmonella in pathogenesis is not know. Enterotoxin gene from Salmonella typhimurium(stn) encodes a 29kDa toxin that has no homology to any other known enterotoxins. Expression of stn is enthanced upon contact with epithelial cell but not all strains having the stn gene express Stn, Based on PCR analysis, we found that all 36 clinical strains of Salmonella isolated in Korea tested carried the stn gene. To understand the trgulation of the stn transcription, the expression of stn was studies in vitro. RNA polymerase was purified by polymin P fraction-ation, DNA-agarose affinity chromatography, and Mono-Q ion exchange chromatography from Salmonella. The expression of stn was inhibited by cAMP·CRP complex by about 50%.

• The Korean Journal of Ecology
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• v.10 no.2
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• pp.53-62
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• 1987

Floristic composition and vertical distribution of Mt. Daedun (western slope) were investigated from 1985 to 1986. The results are as follows; 108 families, 346 genera, 511 species, 2 subspecies, 75 varieties, 5 forma or 593 taxa including 77 cultivars. The floral data showed the ecological characteristics such as the value 346 in Fisher's Index, H-D1-H5 in biological type, 10.9% in urban index of naturalized plants and 60.5% in erect form growth form. Based on the physiognomy and population density of dominant tree species the forest vegetation of Mt. Daedun (western slope) was classified into 5 types; Quercus mongolica forest and Q. variabilis forest at 800m above, Carpinys laxiflora forest and Acer mono forest at 700m to 800m and Sapium japonicum forest at 500m to 800m in altitude. And Lindera erythrocarpa forest and zelkova serrata forest are widely distributed at 400m to 800m in altityde along valley and at mountain foot area.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.255-259
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• 1999

A 6.9-kb DNA fragment including the minimal Bacillus pasteurii urease gene cluster was subcloned into a high-copy-number plasmid vector, pUC19, and the recombinant B. pasteurii urease was overexpressed in Escherichia coli. The recombinant urease was purified 25.9-fold by using combinations of anion-exchange and gel-filtration chromatography followed by Mono-Q chromatography on a FPLC. N-terminal peptide sequencing analyses revealed that two distinct smaller peptide bands resolved on a 10-18％ gradient SDS-PAGE corresponded to UreA and UreB peptides, respectively. It was also shown that the ureB gene was translated from a GUG codon and the first methionine residue was post-translationally cleaved off. The native molecular weight of the recombinant urease was 176,000 and 2 nickel atoms were present per catalytic unit. pH stability studies of the purified enzyme showed that the recombinant Bacillus pasteurii urease is stable in alkaline pH range, which is similar to the enzyme of the evolutionarily related bacterium, Sporosarcina ureae.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.76-76
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• 1995

Virus-encoded HIV-1 reverse transcriptase (RTase) is one of the major targets for the development of drugs for HIV-1 since it is an essential enzyme-for the replication cycle of HIV-1. We cloned the entire reverse trancriptase gene into an inducible expression vector with tac promotor= RTase was stably overexpressed and induced by IPTG and the highly-expressed RTase was purified partially by use of DEAE cellulose and Mono Q column. The partially purified enzyme (663kDa, 51kDa) as exhibited by SDS-PAGE showed the high specific activity (16,570U/mg) when the assay for the RTase activity was carried out using $^3$H-dTTP and poly(rA): oligo(dT)12-18 as the substrate.

• Parasites, Hosts and Diseases
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• v.40 no.2
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• pp.89-92
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• 2002

The cysteine proteases of Paragonimus westermani metacercariae are involved in metacercarial excystment, host immune modulation, and possibly in tissue penetration. In order to clarify the origin of the enzymes, 28 and 27 kDa cysteine proteases in metacercarial excretory-secretory products were purified through the FPLC system using Mono Q column chromatography. The polyclonal antibodies to the enzymes were produced in BALB/c mice. Immunolocalization studies revealed that both cysteine proteases were distributed at the linings of excretory bladder and excretory concretions of the metacercariae. It was suggested that the excretory epithelium of P. westermani undertake the secretory function of metacercarial cysteine proteases, in addition to its role as a route for eliminating waste products.