• Journal of Microbiology and Biotechnology
• /
• v.9 no.6
• /
• pp.870-872
• /
• 1999

The ubiquinone and G+C contents of the bioflocculant-producing fungus, a new Aspergillus strain, were detennined using high-perfonnance liquid chromatography. The internal transcribed spacers 1 and 2 (ITS1 and ITS2), and the 5.8S ribosomal DNA (rDNA) of the strain were amplified and sequenced. The strain contained ubiquinone-l0($H_2$)as a major quinone and the G+C content was 49 mol%. A phylogenetic analysis of the ITS regions indicated that the strain belonged to the genus Aspergillus according to its previously classified morphological characteristics. Based on a sequence homology search, the strain was most closely related to Petromyces muricatus (anamorph, A. muricatus; accession number, AJ005674). The sequence of a new Aspergillus strain in ITS1 and ITS2, and 5.8S rDNA showed 97% homology to P. muricatus. Therefore, the strain is believed to be a new bioflocculant-producing Aspergillus strain.

• Journal of Applied Biological Chemistry
• /
• v.48 no.4
• /
• pp.222-225
• /
• 2005

Strains showing antifungal activity against Cryphonectria parasitica were isolated from coast soil of Taean , Korea. Of 152 strains isolated, 6 strains showed antifungal activity in vitro against C. parasitica. Ta24 strain showed highest activity with 1.6 cm clean inhibition zone. For strain identification, the morphological characteristic and 16S rDNA sequences were determined. Ta24 strain showed 99% homology with Streptomyces sampsonii and was identified as Streptomyces sp.

• Microbiology and Biotechnology Letters
• /
• v.17 no.2
• /
• pp.154-159
• /
• 1989

Chromosomal DNA fragments of Bacillus sp. YA-14 isolated from soil as a potent xylan hydrolyzing bacterium, were ligated to a vector plasmid, pBR322, and used to transfer Escherichia coli HB101 cells. The recombinant plasmid pYDC21 was found to enable the transformants to produce xylanase. pYDC21 was found to contain the 3 kb HindIII fragment originated from the Bacillus sp. YA-14 chromosomal DNA by southern hybridization. The optimum temperature and pH for the reaction of xylanse produced by E. coli (pYDC21) were appeared at 50$_7$C and pH 7.0, respectiveiy. the xylanase enzyme was stable between pH 5.0 and 7.0 and maintained stably up to 4$0^{\circ}C$.

• Journal of Environmental Science International
• /
• v.15 no.11
• /
• pp.997-1002
• /
• 2006

This report presents a voltammetric assay of dinitrotoluene using a DNA immobilized onto a carbon nanotube paste electrode (PE). The cyclic voltammetry (CV) and square wave (SW) stripping voltammetry parameters of the optimized conditions were obtained. An anodic peak current appeared at 0.3 V (versus Ag/AgCl) in a 0.1-M $NH_4H_2PO_4$ electrolyte solution. The detection limit was found to be $0.6ngL^{-1}$(S/N = 10), within a deposition time of 100 sec.

• Genomics & Informatics
• /
• v.11 no.3
• /
• pp.121-128
• /
• 2013

The introduction of metagenomics into the field of virology has facilitated the exploration of viral communities in various natural habitats. Understanding the viral ecology of a variety of sample types throughout the biosphere is important per se, but it also has potential applications in clinical and diagnostic virology. However, the procedures used by viral metagenomics may produce technical errors, such as amplification bias, while public viral databases are very limited, which may hamper the determination of the viral diversity in samples. This review considers the current state of viral metagenomics, based on examples from Korean viral metagenomic studies-i.e., rice paddy soil, fermented foods, human gut, seawater, and the near-surface atmosphere. Viral metagenomics has become widespread due to various methodological developments, and much attention has been focused on studies that consider the intrinsic role of viruses that interact with their hosts.

• Journal of Plant Biotechnology
• /
• v.36 no.3
• /
• pp.224-229
• /
• 2009

Human lactoferrin is an iron-binding glycoprotein with many biological activities, including the protection against microbial and virus infection and stimulation of the immune system. We introduced a human lactoferrin (hLf) cDNA under the control of 35S promoter into sweet potato by particle bombardment. Transgenic plants were regenerated via somatic embryogenesis. Transgenic plants were produced typical tuberous roots in soil. PCR, Southern and northern analyses confirmed that the hLf cDNA was incorporated into the plant genome and was properly expressed in plants. Western blot analysis showed that the 80 kDa full length hLf protein was produced in transgenic tuberous roots. Overall results indicated that sweet potato would be an excellent host to produce human therapeutic proteins.

• Journal of Food Hygiene and Safety
• /
• v.9 no.4
• /
• pp.205-211
• /
• 1994

From 120 soil and activated sludge, the strains able to grow on benzoate and m-Toluate have been isolated after selective enrichment which were later identified as Psudomonas sp. according to its morphological and biochemical characteristics. Ben-2 strain contained two plasmid DNA having about 120 Kb and below 2.0 Kb by agarose gel electrophoresis. Form the comparative investigation of catechol 1,2-oxygenase and catechol 2,3-oxygenase activities in Ben-2 strain and its cured strain, Ben-2 strain has both of these two enzymes while cured strain has catechol 1,2-oxygenase only.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.12
• /
• pp.1908-1914
• /
• 2008

An alkaliphilic bacterium, Bacillus clausii SKAL-16, was isolated from soil that had been contaminated with vegetable oil. The optimal pH and general pH range for bacterial growth was 8, and 7 to 10, respectively. The bacterium could grow on tributyrin and glycerol, but could not grow on acetate and butyrate. The SKAL-16 strain excreted butyric acid during growth on tributyrin, and selectively ingested glycerol during growth on a mixture of butyric acid and glycerol. The SKAL-16 generated intracellular lipase, but did not produce esterase and extracellular lipase. The DNA fragment amplified with the chromosomal DNA of SKAL-16 and primers designed on the basis of the esterase-coding gene of Bacillus clausii KSM-KI6 was not identical with the esterase-coding gene contained in the GenBank database. Pyruvate dehydrogenase, isocitrate dehydrogenase, and malate dehydrogenase activities were detected in the cell-free extract (crude enzyme).

• Journal of Microbiology
• /
• v.34 no.2
• /
• pp.166-171
• /
• 1996

Genetic analysis was conducted on newly isolated coliphages form soil by using a RAPD assay. From the initial result, the coliphages were turned out to be different form one another but were closely related to .psi..lambda. due to the fact that they shared the samed RAPD maker in which other T phage testings failed to show. By using the primers EC01 or EC02, a fast genetic mutation of .psi.C1 was found by producing specific RAPD markers on the phages from the first filial progeny to the second filial progeny. When we made a RAPD assay with combined primers (EC01, EC05 and EC08), the genetic mutation was again confirmed in .psi.C1. The assay detection showed mutations in other coliphages such as .psi.C2 and .psi.C3 by revealing specific RAPD bands among different progeny phages, where genetic instability of the coliphages in implied.

• Journal of Microbiology and Biotechnology
• /
• v.15 no.2
• /
• pp.227-233
• /
• 2005

Fungal strain CGF was isolated from the soil of ChungNam Province, South Korea. Based on the 28S rDNA sequence analysis and the sequence of the internal transcribed spacer (ITS) region of ribosomal DNA, together with morphological and cultural characteristics, this strain was identified as Aspergillus sclerotiorum and renamed Aspergillus sclerotiorum CGF. This is the first strain of Aspergillus sclerotiorum identified in Korea. When the antifungal activity of A. sclerotiorum CGF was evaluated, among the phytopathogenic fungi, mycelial growth of only Phytophthora species was inhibited. Oermination of P. capsid zoospore was also inhibited. The bioactive compound of A. sclerotiorum CGF was highly thermo- and pH-stable.