• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.973-978
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• 2001

The bacterial flagellar motor is a molecular machine that couples proton or sodium influx to force generation, mostly for driving rotation of the helical flagellar filament. In this study, we cloned a gene (motX) encoding a component of the sodium-driven flagellar motor from Vibrio fluvialis. The nucleotide sequence of the motX gene, composed of 633 bp and 211 amino acid residues, was determined. Overexpression of the motX gene in Escherichia coli using a strong promoter induced growth inhibition and cell lysis. The lethal effect of E. coli was suppressed by adding amiloride, as a potent inhibitor for the sodium channel. Electron microscopic observation of the expressed protein indicated that MotX protein induced by isopropyl ${\beta}$-D-thiogalactopyranoside caused the lysis of host cell.

• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.467-471
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• 1986

Yeast cell wall lytic enzyme was purified from Fusarium moniliforme by ammonium sulfate fractionation and gel column chromatography. The lytic activity was found to consist of three enzyme activities which were resolved on Sephadex G-100. The first peak on chromatogram exhibited proteolytic, lytic and laminarinase activities, and the second had both lytic and laminarinase activities, whereas the third peak was shown to contain lytic activity only. Three enzyme activities showed the synergistic effect and reducing agents accelerated the yeast roil wall lysis. This indicates that lytic, proteolytic and laminarinase activity acted cooperatively in the lysis of intact cells. Tannic acid precipitate of crude enzyme constituted of three enzyme activities had a high lytic activity on viable yeast cell and has proved useful in yeast protoplast formation.

• Journal of Microbiology
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• v.39 no.3
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• pp.219-225
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• 2001

Phage typing is currently used for typing of Staphylococcus aureus strains beyond the species level in epidemiological studies. A total of 168 Staphylococcus aureus isolates from chicken meat and chicken by-products were phage-typed using the international bacteriophage set for typing Staphylococcus aureus of human origin. One hundred and forty-eight (88.79%) strains were phage-typeable (at least one phage produced 20 or more plaques of lysis). Lysis by phages of group Ⅲ was the mast frequent with 99 (58.93%) sensitive strains. This fact coincides with results of other authors. Twenty-nine different phage patterns were observed and three (95, 75/84 and 6/1030/W57) were most common. One hundred and thirty-two (89.19% of typeable strains) skewed these or indistinguishable (only one phage reaction difference) patterns. Twenty-six out of seventy chicken samples (37.14%) harboured more than one phage type of Staphylococcus aureus. This fact emphasizes the convenience of subtyping several Staphylococcus aureus isolates from the same sample in epidemiological studies. 80% of sausages and hamburgers contained the same Staphylococcus aureus phage types, which wore not found in any of the other food types. This fact suggests a cross contamination during the processing of these foods. Phages 6, 75, 84, 1030 and W57 skewed the greatest activity. None of the Staphylococcus aureus strains were sensitive to phages 47, 81 and 94.

• BMB Reports
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• v.40 no.3
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• pp.444-447
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• 2007

Polymerase chain reaction (PCR) is a powerful technique in molecular biology and is widely used in various fields. By amplifying DNA fragments, PCR has facilitated gene cloning procedures, as well as molecular genotyping. However, the extraction of DNA from samples often acts as a limiting step of these reactions. In particular, the extraction of PCR-compatible genomic DNA from higher plants requires complicated processes and tedious work because plant cells have rigid cell walls and contain various endogenous PCR inhibitors, including polyphenolic compounds. We recently developed a novel solution, referred to as AnyDirect, which can amplify target DNA fragments directly from whole blood without the need for DNA extraction. Here, we developed a simple lysis system that could produce an appropriate template for direct PCR with AnyDirect PCR buffer, making possible the direct amplification of DNA fragments from plant leaves. Thus, our experimental procedure provides a simple, convenient, non-hazardous, inexpensive, and rapid process for the amplification of DNA from plant tissue.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1031-1034
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• 1999

Circulating lymphocytes collected from control and heat-stressed buffaloes were subjected to in vitro culture with glucocorticoids, epinephrine or serotonin and their effect, if any, on the release of intracellular prolactin (PRL) was studied using ELISA and C-ELISA techniques. It was noted from the study that PRL level was higher in lymphocytes than in plasma of the control and heat-stressed animals, and that the PRL levels increased in the plasma of heat-stressed animals compared to that of non stressed animals with a significant decrease in lymphocytic PRL content by heat stress. Epinephrine and serotonin significantly increased the release of intracellular PRL from the lymphocytes of both in the control and the heat-stressed buffaloes but release of PRL from lymphocyte was not significantly changed by cortisol treatment in both control and heat-stressed buffaloes as compared to epinephrine and serotonin in vitro. When lympocytes were incubated with serotonin, it caused drastic lysis of the lymphocytes but epinephirine and cortisol did not show any lysis. It may be concluded from this study that hormones like epinephrine or serotonin known to increase during stress, release intracellular PRL from lymphocytes, the satellite PRL storage/synthesizing organ of blood, although the mechanism of the release is different.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.559-564
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• 1998

The polymerase chain reaction(PCR) assay was used for rapid diagnosis from blood and organ samples experimentally infected with Listeria monocytogenes. This method used a pair of primers based on a unique region in the 16S rRNA sequence of L monocytogenes. Procedure A was based on dilution of the blood sample followed by lysis of bacterial cell and direct analysis of the lysate with PCR. In artificially infected blood samples with L monocytogenes, it was possible to detect fewer than 40 cells per ml of blood. However, L monocytogenes was detected low rates on infected organs by the direct PCR. In procedure B, enrichment cultivation was used to increase numbers of bacteria before lysis and PCR. L monocytogenes was detected from 23 samples of 24 liver and spleen, respectively, and 18 samples of 24 blood were found to be positive by PCR on a subset of 72 organ samples, whereas L monocytogenes were detected on 63 organ samples in classical culture technique. It was required to analyze including enrichment steps were 6h and 18h on the procedure A and B, respectively.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.140-145
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• 2018

The most energy-intensive processes in lipids extraction were the disruption of the cell wall of microalgae. Here, we tried to extract lipids through lysis using virus-infecting microalgae, to compare with those by the other two methods using microwave or ultrasonication. The lipids yield using viral infection was not significantly different from those using ultrasonication and microwave oven. This suggests that the same amount of lipids can be obtained with low energy and costs, as well as that microalgal lipids extraction by chlorella virus infection might provide the price competitiveness in biodiesel production even if it will be applied to mass production facilities.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.774-783
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• 2007

In the present study, acidocin 1B, a bacteriocin produced by Lactobacillus acidophilus GP 1B, exhibited profound inhibitory activity against a variety of LAB and pathogens, including Gram-negative bacteria, and its mode of action was to destabilize the cell wall, thereby resulting in bactericidal lysis. Acidocin 1B was found to be heat stable, because it lost no activity when it was heated up to $95^{\circ}C$ for 60 min. It retained approximately 67% of the initial activity after storage for 30 days at $4^{\circ}C$, and 50% of its initial activity after 30 days at $25^{\circ}C$ and $37^{\circ}C$. The molecular mass of acidocin 1B was estimated to be 4,214.65 Da by mass spectrometry. Plasmid curing results indicated that a plasmid, designated as pLA1B, seemed to be responsible for both acidocin 1B production and host immunity, and that the pLA1B could be transformed into competent cells of L. acidophilus ATCC 43121 by electroporation. Our findings indicate that the acidocin 1B and its producer strain may have potential value as a biopreservative in food systems.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.215-222
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• 1984

A fungus producing cell wall lytic enzyme for Rhodotorula glutinis was isolated from local soil and identified partially as a species of Aspergillus fumigatus group. Thd cell wall lytic enzyme was an inducible exoenzyme and composed of at least lytic polysaccharidase and protease which act cooperatively in the lysis of intact cells. The lytic polysaccharidase was not able to hydrolyze ${\beta}-1,\;3\;and\;{\beta}-1$, 6-glucan which have the same types of bond as found in the cell wall of Ascomycetous yeasts. The lytic polysaccharidase alone was sufficient to hydrolyze the fractionated cell wall (alkali-insoluble residues) of R. glutinis, whereas it showed low activity against intact cells.

• The Journal of Natural Sciences
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• v.11 no.1
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• pp.55-63
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• 1999

In this study, the stabilizer, PH and lysis method for optimum condition of S. uvarum protoplast formation were investigated, and also enzyme activity and poly-P formation of intact cell and protoplast mere compared. Upon protoplast formation, incubation time of 5 hours in snail gut enzyme and 3 hours in drisielase were reignited. 0.8 Mole mannitol and 6 mole KCl were apt to protoplast formation. Protoplast was contained less 22-27 percentage in ALPase, 4-15 percentage in ACPase than intact cell. Accumulation of inorganic polyphosphate did not increase significently in protoplast compared with intact cell.