• 미생물학회지
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• 제22권4호
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• pp.215-222
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• 1984

Rhodotorula gl$\varkappa$tinis 세포벽에 작용하는 용해 효소 생산곰팡이를 토양으로부터 분리하였고, Aspergillus f'||'&'||'micro;mig$\alpha$tus에 속하는 species로 동정되었다. 이 세포벽 용해효소는 세표외 유도효소였으며 lytic polysaccharidase 와 protease로 구성되어 생세포 용해에 공동으로 착용하였다. 이 lytic polysaccharidase는 Ascomycetous 효모에서의 주 구성 결합인 ${\beta}-1,3-$와 ${\beta}-1$, 6-glucan에는 작용치 않았다. 이 효소는 생세포에는 역가가 낮았지만 R. glutinis의 분획된 세포액에는 protease의 도움없이 작용할 수 있었다.

• 한국미생물·생명공학회지
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• 제24권3호
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• pp.299-303
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• 1996

Isolation, identification, and culture conditions of a lytic enzyme producing microorganism against Lacto- bacillus plantarum were investigated. The selected strain was gram-positive, rod (0.7 $\times$ 2.7 $\mu$m in size), and non-motile. The strain did not have any flagella and spores. According to its cultural and physiological characteristics, the strain was identified as Bacillus sp. The optimal pH and temperature for the production of lytic enzyme were 8.0 and 30$\circ$C, respectively. The maximum enzyme activity showed 1.5 units/ml in the medium composed of 1% peptone and 0.1% NaCl.

• 한국미생물·생명공학회지
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• 제30권1호
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• pp.33-38
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• 2002

Lactobacillus plantarum 용균 효소를 생산하는 균주를 배양하여 생산된 효소를 정제한 결과 비활성도가 5.8 units/mg protein 이었고 정제도 8.3배, 수율은 30%이었다. 정제효소의 분자량은 gel filtration과 SDS-polyacrylamide gel eletrophoresis를 이용하여 측정한 결과 60,000 kDa 이었다. 용균 효소의 최적 반응 시간은 20분이었으며 최적 온도는 4$0^{\circ}C$, 최적 pH는 3.0이었다. 온도 안정성은 각 온도에서 30분간 처리하였을 때 $30^{\circ}C$까지는 안정하였으나 4$0^{\circ}C$에서는 80% 활성을 나타내었다. 효소의 pH 안정성은 실온에서 1시간 처리하였을 때 pH 4~7에서 안정성을 나타내었다.

• Animal Bioscience
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• 제36권8호
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• pp.1285-1292
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• 2023

Objective: The objective of this study was to develop a novel endolysin (PanLys.1) for the specific killing of the ruminal hyper-ammonia-producing bacterium Peptostreptococcus anaerobius (P. anaerobius). Methods: Whole genome sequences of P. anaerobius strains and related bacteriophages were collected from the National Center for Biotechnology Information database, and the candidate gene for PanLys.1 was isolated based on amino acid sequences and conserved domain database (CDD) analysis. The gene was overexpressed using a pET system in Escherichia coli BL21 (DE3). The lytic activity of PanLys.1 was evaluated under various conditions (dosage, pH, temperature, NaCl, and metal ions) to determine the optimal lytic activity conditions. Finally, the killing activity of PanLys.1 against P. anaerobius was confirmed using an in vitro rumen fermentation system. Results: CDD analysis showed that PanLys.1 has a modular design with a catalytic domain, amidase-2, at the N-terminal, and a cell wall binding domain, from the CW-7 superfamily, at the C-terminal. The lytic activity of PanLys.1 against P. anaerobius was the highest at pH 8.0 (p<0.05) and was maintained at 37℃ to 45℃, and 0 to 250 mM NaCl. The activity of PanLys.1 significantly decreased (p<0.05) after Mn²⁺ or Zn²⁺ treatment. The relative abundance of P. anaerobius did not decrease after administration PanLys.1 under in vitro rumen conditions. Conclusion: The application of PanLys.1 to modulate P. anaerobius in the rumen might not be feasible because its lytic activity was not observed in in vitro rumen system.

• 한국미생물·생명공학회지
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• 제24권6호
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• pp.678-686
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• 1996

To improve the preservation of Kimchi, we isolated Lactobacillus plantarum lytic enzyme-producing strain from soil, and the enzyme was purified and characterized. From the observation of cultural and morpho- logical characteristics, the isolated strain was identified as Metarrisium anisopliae (Metschn.) Sorok. The enzyme was purified to 75-folds with 40% yields through affinity adsorption and CM-Sephadex C-50 column chromatog- raphy. The optimum pH and temperature for lytic activity are 4.0 and 40$\circ$C, respectively, and the enzyme acitvity is stable between pH 3.0 and 9.0, and up to 50$\circ$C. The enzyme is a monomeric protein with molecular weight of 40,000 daltons by SDS-PAGE and gel filtration. The enzyme is endopeptidase which breaks the peptide linkage of Lactobacillus plantarum peptidoglycan. The lytic action spectra confirmed that Leuconostoc mesenteroides, a useful strain for the fermentation of Kimchi, is not lysed by the enzyme. The enzyme activity is inhibited by N-bromosuccinimide (NBS), which probably indicates the involvement of tryptophan residue in active site of the enzyme, and also inhibited by Ag$^{+}$. The amino acid composition analysis showed that the enzyme contains more acidic amino acids than basic ones, and composition of alanine, glycine, proline and tyrosines was very high.

• KSBB Journal
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• 제23권3호
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• pp.187-192
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• 2008

Lysozyme-producing microorganisms were isolated to obtain bacteria which can efficiently solubilize microbial cells. Cells of normal and chloroform-treated Escherichia coli and Micrococcus Iysodeikticus were used as model substrates to isolate lysozyme-producing microorganisms and investigate the efficiency of cell lysis. The culture supernatant of the isolate New1 (98% similarity of 16S rDNA sequence with Thermomonas haemolytica) showed different lytic characteristics for different substrates. Thermal treatment (autoclave) of substrate cells showed a significant effect on cell solubilization by culture supernatant of the New1. For autoclaved substrate cells, E. coli, M. Iysodeikticus and chloroform-treated E. coli were solubilized by 58.7%, 49.4% and 79.1%, respectively, in the culture supernatant of New1. The lytic activity of New1 was mainly caused by lysozyme produced by the isolate. It was also showed that New1 exhibited high protease activity and a little cellulase activity.

• 한국미생물·생명공학회지
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• 제24권4호
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• pp.445-451
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• 1996

The strain YCH-37, which produces yeast cell wall lytlc enzyme, was isolated from soil. From the microscopic observation, morphological and cultural characteristics, this strain was identified to fungus, Dicyma sp. So, we named this strain as Dicyma sp. YCH-37. The lytic enzyme effectively lysed Salmonella typhimurium among intact living bacteria and Torulopsis, Hansenula, Zygosaccharomyces among intact living yeast, as well as autoclaved yeast strains. The yeast cell wall lytic enzyme was succesively purified to 204 folds with 13% yields through yeast glucan affinity adsorption and DEAE-cellulose column chromatography. The enzyme was identified to monomeric protein with molecular weight of 25,000 daltons from the results of SDS-PAGE and gel filtration. The optimum pH and temperature for the yeast lytic activity were 8.0 and 50$\circ$C, respectively. The enzyme was stable up to 40$\circ$C, and between pH 4.0-pH 10.0.

• Applied Biological Chemistry
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• 제20권1호
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• pp.123-129
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• 1977

효모세포벽 분해효소를 생산하는 386주(株)의 미생물을 분리하여 그중 강한 1주(株)를 선발 동정(同定)하고 선정균의 효소생산조건을 검토하여 다음과 같은 결과를 얻었다. 1. 선정한 M-10 strain은 Humicola sp.로 동정(同定) 되었다. 2. 선정균의 효소생성은 pH 6.0 $33^{\circ}C$에서 가장 양호하였다. 3. 탄소원으로서 baker's yeast 4%가 Iytic enzyme 생산에 가장좋았고 기타 laminarin과 dextrin 등이 효과적이었으며 질소원도 peptone이 다소 효과적이나 baker's yeast로서 족하였다. 4. 효소생산에 $K_2HPO_4$ 0.1%와 $MgSO_4{\cdot}7H_2O$ 0.01%의 첨가가 가장 효과적이고 기타 염류의 첨가는 효과가 없었다. 5. 선정한 배지조성에서 72시간 진탕배양으로 최고에 달하였다.

• Journal of Ginseng Research
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• 제13권2호
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• pp.223-228
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• 1989

Natural killer (NK) cells are a heteroguneous subpopulation of lymphocytes that spontaneously exhibit cytotoxic activity against various virus-Infected and neoplastic target cells without prior exposure to a specific antigen. It was thought that NK calls play an important role in immunosurvrillanre against viral agents and tumors, and in prevention of metastasis. Recently, several reports have indicated evidence that ginseng extracts show a significant stimulatory effect on the humoral and cellular immune responses. This evidence gives support to the suggestion that the anticarcinogenic effect of ginseng may be due to the effect of ginseng on the immunological system. Treatment with total, diol, and triol saponin resulted in an increase in NK cytotoxic activity, but no enhancement of the lytic activity due to the natural killer cytotoxic factor (NKCF). Therefore, these results suggest that the augmentation of NK activity by ginseng saponin fractions may not be due to the activation of NKCF lytic activity.

• 대한수의학회지
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• 제43권1호
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• pp.87-94
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• 2003

The lytic activity of the set of swine and chicken phages which were derived from lysogenic Staphylococcus hyicus strains of swine and chicken origin was compared by means of S. hyicus isolated from swine, chicken and cattle. Of the 80 strains each from swine and chicken, 71 (88.8%) of strains from swine and all the strains of chicken origin were found to be lysogenic. Swine phages showed wider range of lytic activity to the examined strains than that of chicken phages. Using chicken phages at $100{\times}routine$ test dilution (RTD), 25.0%, 85.6% and 50.0% of swine, chicken and bovine strains were lysed, respectively. However, when the set of swine phages was used at $100{\times}RTD$, higher frequency of the typable strains was found in strains of swine and chicken origin (73.8% and 90.2%). Phage F12 and L16 from chicken set were found to be highly active with chicken and bovine strains. On the contrary, all the swine strains were completely resistant to lysis by the two phages at $100{\times}RTD$. Thirteen (12.5%) of 104 S. aureus strains, 1 (1.8%) of 55 S. simudance strains, 31 (58.5%) of 53 S. chromo genes strains, and none of 31 strains of other coagulase-negative Staphylococcus species isolated from bovine mastitis were typable with the set of swine phages.