• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.178-181
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• 2004

A gene encoding an extracellular nuclease was cloned from Aeromonas hydrophila strain ATCC14715. The gene was overexpressed and the enzyme was purified by fusing to maltose binding protein. It was shown that the protein possessed DNase activity on both single-stranded and double-stranded DNAs. It exhibited both endo- and exonuclease activities. It was also shown that the protein had an RNase activity. Possible roles of this extracellular enzyme in the A. hydrophila life cycle are discussed.

• Journal of Microbiology
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• v.34 no.1
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• pp.40-48
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• 1996

We have examined the chromatin structure of the HMRE/HSP82 and HMRa/HSP82 allels using three complementary approaches : DNase I chromating footprinting, micrococcal nuclease (MNase) nucleosome-protected ladder assay, and an in vivo E. coli dam methylase accessibility assay. The footprinting results indicate that the promoter and silencer sequences are assembled into nucleoprotein complexes which exhibit no detectable change in structure, despite a 70-fold range in expression levels. In addition, the promoter region of the HMRa/HSP82 allele is cleaved randomly by MNase in all cases, indicating the absence of anonical nucleosomes over this region irrespective of SIR4 or heat-shock. Finally, no discernible difference in the accessibility of the HMRE/HSP82 locus to dam methylase in SIR4 vs. sir4 cells was seenm which again suggests that the chromatin structure of HMRE/HSP82 allele is identical regardless of SIR4. Altogether, our results indicate that in contrast to other observations of the silent mating-type loci, no discernible structural alteration is detected at either HMR/HSP82 allele regardless of SIR genetic background or transcriptional state of the gene.

• Journal of Pharmaceutical Investigation
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• v.39 no.5
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• pp.339-343
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• 2009

Recently, co-delivery of drug and gene has been attempted for higher therapeutic effects of anticancer agents. In this study, cationic liposomes were prepared using 1,2-dioleoyl-3-trimethylammoniopropane (DOTAP) as a cationic lipid to investigate the effect of drug loading on the physicochemical characteristics of cationic liposomes/DNA complexes. The complex formation between cationic liposomes and negatively charged plasmid DNA was confirmed and the protection from DNase was observed. Particle size of complexes was reduced not by drug loading, but by the increased ratio of cationic lipid to plasmid DNA. Meanwhile, zeta potential of complex was increased by the addition of cationic liposomes to complexes and the effect of drug loading on the zeta potential was not much higher than on particle size. Gel retardation of complexes was indicated when the complexation weight ratios of cationic lipid to plasmid DNA were higher than 24:1 for drug free complexes and 20:1 for drug loaded ones, respectively. Agarose gel retardation showed the similar complexation between plasmid DNA and drug free liposomes or drug loaded liposomes. Both complexes protected plasmid DNA from DNase independent of complexation temperature. From the results, drug loading may affect not the complex formation of cationic liposomes and plasmid DNA, but the particle size of complex.

• Journal of fish pathology
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• v.7 no.1
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• pp.23-36
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• 1994

A total of 8 strains of Staphylococcus epidermidis isolated in land-marine tank system of Kyongnam and Kyongbuk. Prefecture were tested for the biological and biochemical characteristics. These strains were isolated from pathologic specimens of cultured flounder. Paralichthys olivaceus. Growth of the isolates was good on BHIA, HIA. Staphylococcus No. 110 and ETGP. Growth was good at NaCl concentration between 2.0 and 3.0%, about $30^{\circ}C$ and at pH values about 7.0. DNase and coagulase production were negative, and all isolates except FSJ-2 strain were positive in hemolysis. Urease was positive reaction, and novobiocin resistance was negative. Acid was produced anaerobically from glucose and maltose. All isolates except FSJ-19 strain produced weakly were negative in anaerobic acid production from mannitol. Acid was produced aerobically from glucose, fructose, galactose, sucrose, maltose and dextrine. But all isolates were not gas production. In characterization of clinically isolates, four different biotype codes were obtained when the all isolated were tested simultaneously. Four different antibiotic susceptibility patterns were obtained. On the basis of these characteristics, the isolates were identified as Staphylococcus epidermidis.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.205-208
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• 1986

The 23 serovars of Bacillus thuringiensis strain were commonly gram-positive and motile, formed endotoxin crystals, produced acid and alkali in the KIA media, and acid from glucose, hydrolyzed starch, and reduced nitrate but did not produce H$_2$S, oxidase and indole, did not decompose lysine, ornithine, phenylalanine, malonate, lactose, dulcitol, adonitol, inositol, sorbitol, arabinose, raffinose, rhamnose, maltose, and xylose. Eighteen serovars were positive in the MR tests and 15 in the VP tests. Four serovars used citrate. Five serovars produced urease, 5 $CO_2$ from glucose, 2 DNase, and 15 lecithinase. Twelve serovars decomposed arginine, 11 did sucrose, 2 manitol, and 9 salicin Serovar tohokuensis did not hemolyze, but the others did.

• Journal of Microbiology
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• v.33 no.3
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• pp.191-195
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• 1995

IciA protein has been shown as an inhibitor for the initiation of E. coli chromosomal DNA replication at oriC. IciA protein binds the AT-rich region in oriC and then blocks the initiation of chromosomal DNA replication. Two binding sites for IciA protein were identified in dnaA gene, encoding the initiator for the E. coli chromosomal replication, promoter region by gel-shift assay and DNase I footprinting, One, named as IciA site I, is located upstream of the dnaA promoter 1P. The other, named as IciA site II, is located downstream of the dnaA promoter 2P. The sequence comparison of the regions protected from the DNase I cleavage did not result in a clear consensus sequence for the binding of IciA protein, suggesting that IciA protein may be a member of multimeric complex dsDNA binding proteins. This study provided information about the binding mode of IciA protein. Even though the IciA site II and IciA binding site in oriC seem to be composed of two IciA binding units, one binding unit is likely enough to cause the binding of IciA protein to the IciA site I. The binding of IciA protein to the dna4 promoter implies that IciA protein may involve not only the control of the initiation of chromosomal DNA replication but also the control of the dna4 gene expression.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.7-12
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• 1994

One bacterial strain, that had made the largest inhibition zone at the antagonism assay and also that lost the inhibition activity by the protease treatment, was isolated from raw milk. That strain was identified as Streptococcus salivarius subsp. thermophilus. The specific growht rate of this strain was maximum at 45$\circ $C. However, at this temperature the strain produced no bacteriocin. The bacteriocin activity was quite stable even at high temperature. Moreover, the activity of the vacteriocin was sensitive to proteases. but not to $\alpha $-amylase, DNase I, or RNase.

• KSBB Journal
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• v.17 no.3
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• pp.283-289
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• 2002

The present study was aimed at investigating the metabolic regulation of insulin-like growth factor-I(IGF-I) expression in fasting animals. The expression of IGF-I gene was determined by a solution hybridization/RNase protection assay using total RNA from control, 4d-fasting, and 2d-fasting-refed rats. The levels of IGF-I transcripts were reduced in 4d-fasting than in control by decreasing its transcriptional rate, which was measured through nuclear nun-on assay. DNase I footprinting, which was performed using nuclear extracts from fasting rat, demonstrated protein binding to a sequence that extended from +179 to +210 (termed region B). These data suggest that the expression of IGF-I is transcriptionally regulated through DNA-liver enriched protein binding in a sequence which is located downstream from major transcription initiation site of IGF-I gene.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.130-136
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• 2011

Five strains of Actinomyces were isolated from freshwater sponges, Baikalospongia and Lubomirskia, in Lake Baikal. By 16S rRNA sequencing, isolates were identified as Streptomyces griseoplanus, S. halstedii, S. violascens, S. flavovirens, and S. microflavus. Isolates had different characteristics of growth temperature, carbon utilization, enzyme activity, and cellular fatty acid composition. Optimum growth conditions of isolates were $30-37^{\circ}C$, pH 8-9, and 0-1.5% salt concentrations. Major fatty acid compositions were anteiso-$C_{15:0}$, iso-$C_{15:0}$, and iso-$C_{16:0}$. Strain ATS-BA-19 had DNase and chitinase activities and strain ATS-BA-16 had cellulase and protease activities. Colonies of strain ATS-BA-15 and ATS-BA-19 made inhibition zone of Pseudomonas aeruginosa.

• Journal of Pharmaceutical Investigation
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• v.31 no.3
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• pp.185-190
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• 2001

Human papillomavirus (HPV) infection is known to cause cervical cancers. Human papillomavirus-like particles (VLP) have been studied as preventive vaccines of cervical cancers. To develop VLP as a therapeutic gene carrier, we studied the method to encapsulate cytokine genes in virus-like particles. HPV type 16 capsid L1 genes were amplified by polymerase chain reaction and cloned into T vector. L1 gene was then inserted into baculovirus transfer vector. The clone of baculovirus encoding L1 gene was isolated and used to express L1 protein in Sf 21 insect cells. VLP were purified by CsCl density gradient and ultracentrifugation. VLP were disassembled to capsomer units by treatment of a reducing agent. Given that interleukin-2 (IL-2) genes have been used in anticancer gene therapy and as a molecular adjuvant, IL-2 cytokine plasmids were chosen as a model gene. IL-2 plasmids were incubated with the disassembled capsomer suspension. To reassemble the particles, the mixture of capsomers and cytokine plasmids was dialyzed. The disassembly and reassembly of VLP were confirmed by transmission electron microscopy. The entrapment of cytokine plasmids in reassembled VLP was tested by the stability of plasmids against DNase I. After treatment of reassembled virus-like particles with DNase I, discrete IL-2 DNA band was observed. Our results indicate that IL-2 cytokine plasmid (3.5 kb size) can be encapsulated in the virus-like particles, suggesting the potential of VLP as a gene delivery system. Moreover, VLP containing the adjuvant cytokine plasmids might function as more effective subunit vaccines.