• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.6-11
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• 1993

An autonomously replicating sequence (Kf-ARS1) of Kluyveromyces fragilis was cloned from the genomic library which was constructed using pHN134 as a cloning vector to make a new host-vector system for the production of heterologous protein from K. fragilis as a host. The cloning vector pHN134 was composed of $Km^r, Ap^r$ and multiple cloning site in LacZ . A clone carrying Kf-ARS1 was isolated and the recombinant plasmid was designated as pIKD102. The cloned fragment was 2.3 kb (EcoRI/EcoRI) in length. Subcloning experiment showed that the region for ARS activity was 1.5 kb (SalI/EcoRI) fragment. It was shown that the Kf-ARS1 was active in Saccharomyces cerevisiae and Kluyveromyces fragilis.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.45-48
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• 2002

This paper discusses the surface roughness of negative chemically amplified resists, SAL601 exposed by I-beam direct writing. system. Surface roughness, as measured by atomic force microscopy, have been simulated and compared to experimental results. Molecular-scale simulator predicts the roughness dependence on material properties and process conditions. A chemical amplification is made to occur in the resists during PEB process. Monte-Carlo and exposure simulations are used as the same program as before. However, molecular-scale PEB simulation has been remodeled using a two-dimensional molecular lattice representation of the polymer matrix. Changes in surface roughness are shown to correlate with the dose of exposure and tile baking time of PEB process. The result of simulation has a similar tendency with that of experiment.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.7-12
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• 2000

The expression of the mouse $\alpha-amylase$ gene in the methylotrophic yeast, P pastoris was investigated. The mouse $\alpha-amylase$ gene was inserted into the multi-cloning site of a Pichi a expression vector, pPIC9, yielding a new expression vector pME624. The plasmid pME624 was digested with SalI or BglII, and was introduced into P. pastoris strain GSl15 by the PEG1000 method. Fifty-three transformants were obtained by the transplacement of pME624 digested with SaiII or BglII into the HIS4locus $(38\;of\;Mut^+\;clone)$ or into the AOX1 locus $(15\;of\;Mut^s\;clone)$. Southern blot was carried out in 11 transformants, which showed that the mouse $\alpha-amylase$ gene was integrated into the Pichia chromosome. When the second screening was performed in shaker culture, transformant G2 showed the highest $\alpha-amylase$ activity, 290 units/ml after 3-day culture, among 53 transformants. When this expression level of the mouse $\alpha-amylase$ gene is compared with that in recombinant Saccharomyces cerevisiae harboring a plasmid encoding the same mouse $\alpha-amylase$ gene, the specific enzyme activity is eight fold higher than that of the recombinant S. cerevisiae.

• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.297-302
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• 1985

The 7.1 Mdal Xbaf fragment of Bacillus pasteurii ATCC 11859 containing gene for urease was inserted into the Xbal site of bifunctional plasmid pGR71, and its urease gene was cloned and expressed in E. coil RRI. But the cloned gene was not expressed in Bacillus subtilis BR151 in consequence of deletion of inserted DNA fragment. The recombinant plasmid thus formed was named pGU66. The restriction map of the plasmid pGU66 was determined, and the size of the plasmid was estimated to be 12.6 Mdal by double digestion of restriction enzymes of the plasmid. The urease of the cloned strain was accumulated in periplasmic space and very similiar to that of donor strains in their enzymatic properties.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.305-308
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• 1990

In order to clone the gene coding for 3-isopropylmalate dehydrogenase of Muyveromyces fragilis, a shuttle plasmid vector pHNll4 was used. It can serve as a cloning vector in Saccharomyces cerevisiae DBY746 for other Sau3AI-cleaved DNA segment of Kluyveromyces fragilis. Two cloned fragments which complement the leu2 mutation of Saccharomyces cerevisiae and E, coli were obtained. Their length was 4.4 kb an 3.5 kb, and their orientation was opposite each other. From the fact that the two recombinant plasmids were expressed in Saccharomyces cerevisiae and E, coli, probably the two inserts had the promoter of Ktuyveromyces fi-agilis and that of Kluyveromyces fiagilis was efficiently assosiated with RNA polymerase of Saccharomyces cerevisiae and E. coli. According to the result of Southern hybridization, we thought that the cloned fragment has low homology with 3-isopropylmalate dehydrogenase coding region of E. coli and Saccharomyces cerevisiae.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.166-177
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• 2005

Purpose : The purpose of this study was to examine the molecular epidemiology and genetic variability of adenovirus(Ad) serotypes Ad1, Ad2, and Ad5 over 14 years in Korea. Methods : A total of 382 adenoviral strains isolated from the nasopharyngeal aspirates of children with lower respiratory tract infections in Seoul, Korea from November 1990 to February 2003 were serotyped by neutralization assay with type-specific antisera. Viral DNAs were extracted from infected cell lysates by the modified Hirt procedure. Genome type(GT) was determined by DNA restriction analysis with 12 restriction enzymess(BamHI, BclI, BglI, BglII, BstEII, EcoRI, HindIII, HpaI, SalI, SmaI, XbaI, and XhoI). To evaluate the genetic relatedness, pairwise comigrating restriction fragments(PCRF) analysis was performed. Results : Of 382 strains, 33 strains(9%) were Ad1, 45 strains(12%) were Ad2, and 24 strains(6%) were Ad5. Eighteen GTs(Ad1p1-Ad1p7, Ad1a, Ad1b, Ad1b1-Ad1b3, Ad1c, Ad1d, Ad1e, Ad1e1, Ad1e2, Ad1f) among Ad1, 24(Ad2p1-Ad2p11, Ad2a, Ad2a1-Ad2a6, Ad2b, Ad2c, Ad2d, Ad2e, Ad2e1-Ad2e3) among Ad2, and 10(Ad5p1, Ad5p2, Ad5a, Ad5a1-Ad5a7) among Ad5 strains were identified. One or two strains of the vast majority of GTs were isolated during the study period while a few GTs were identified sporadically with more than 2 strains. It is notable that some GTs such as Ad1p5 and Ad5a1 appeared in cluster during a short period. In analysis of genetic relatedness, the degree of PCRFs(pairwise comigrating restriction fragments) for Ad1 varied from 79 to 99%, for Ad2, 82 to 99%, and for Ad5, 85 to 99%. Conclusion : This study established the comprehensive nomenclature systems of Ad1, Ad2, and Ad5. Diverse GTs identified in this study have crucial implications in the genomic diversity and epidemiological characteristics of Ad1, Ad2, and Ad5.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.266-272
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• 2004

We developed a miniaturized solid-state carbonate ion-selective electrode (carbonate ISE) based on one-component room temperature vulcanizing type silicone rubber 730 (730 RTV) without adding plasticizer to the matrix. The optimized carbonate ion selective membrane is prepared with 85.8 wt% of 730 RTV, 11.1 wt% of trifluoroacetyl-p-decylbenzene (TFADB), and 3.1 wt% of tridodecyl-methylammonium chloride (TDMACl). This carbonate ISE exhibited excellent potentiometric properties (i.e., slope: 26.3 mV/dec; selectivity: $logKT^{pot}_{CO_{2},Cl^-}$= -4.00 and $logKT^{pot}_{TCO_{2},Sal^-}$=1.69); and detection limit for $TCO_2:\;4.0{\times}10^{-4}M$). In addition, the early potentiometric properties of the solid-state sensor with optimized membrane composition were not deteriorated for more than 60 days.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.560-567
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• 1998

We have found that Thermoactinomyces vulgaris KFB-Cl00 produces a chitinase. The optimum temperature and pH of the enzyme activity were $55^{\circ}C$ and 6.5. The enzyme was stable after heat treatment at $80^{\circ}C$ for 30 min and stable in acidic and basic conditions (PH 6.0~11.0). The thermostable endo-chitinase from Thermoactinomyces vulgaris KFB-C100 was cloned into the plasmid pBR322 by using E. coli DH5$\alpha$ as a host strain. The positive clone carrying a recombinant plasmid (PKCHI23) with a 4.1-kb fragment containing the chitinase gene was found. The recombinant plasmid was analyzed to determine the essential region for chitinase activity and obtained a 2.3-kb fragment, which was sub cloned into pTrc99A using the PstI and SalI sites to construct pTrc99A/pKCHI23-3. The resulting plasmid exerted high chitinase activity upon transformation of E. coli XL1-Blue cells. Chitinase was overproduced 14 times more in the clone cells than in the wild-type cells and the enzyme was purified to homogeneity. The purified enzyme showed the similar properties as the native chitinase from T. vulgaris in terms of molecular weight and substrate specificity. The catalytic action of the cloned enzyme was an endo type, producing chitobiose as a major reaction product.

• BMB Reports
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• v.35 no.6
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• pp.637-641
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• 2002

Only one natural promoter that interacts with bacteriophage K11 RNA polymerase has so far been identified. To identify more, in the present study restriction fragments of the phage genome were individually assayed for transcription activity in vitro. The K11 genome was digested with two 4-bp-recognizing restriction enzymes, and the fragments cloned in pUC119 were assayed with purified K11 RNA polymerase. Eight K11 promoter-bearing fragments were isolated and sequenced. We report that the nine K11 promoter sequences (including the one previously identified) were highly homologous from -17 to +4, relative to the initiation site at +1. Interestingly, five had -10G and -8A, while the other four had -10A and -8C. The consensus sequences with the natural -10G/-8A and -10A/-8C, and their variants with -10G/-8C and -10A/-8A, showed nearly equal transcription activity, suggesting residues at -10 and -8 do not regulate promoter activity. Using hybridization methods, physical positions of the cloned promoter-bearing sequences were mapped on SalI-and KpnI-restriction maps of the K11 genome. The flanking sequences of six cloned K11 promoters were found to be orthologous with T7 or T3 genomic sequences.

• Food Science and Preservation
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• v.13 no.2
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• pp.241-245
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• 2006

The biofunctional properties of traditional Doenjang supplemented with the extract of herb medicines (refer as DHM) were examined DHM divided to four groups, I, II, III and IV according to herb medicines were added. Nitrite scavenging-activities from all 4 groups of DHMs were significantly higher than that of control. Also hydrogen donating-activities from all 4 groups of DHMs were slightly higher than that of control. Antibacterial activities against pathogenic bacteria such as Streptococcus mutant and Salmonella enteritidis and fibrinolytic activity of all DHMs on fibrin plate were higher than those of control. On the other those of groups III and IV were higher in sensory score, biofunctional and antimicrobial activities than those of group I, II and control. Therefore, the usage of extract of Korean herb medicines instead of water to make Doenjang will effective in development of traditional soybean Doenjang with the biofunctional properties.