• 한국미생물·생명공학회지
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• 제5권1호
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• pp.13-17
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• 1977

한국야쿠르트 제조공장의 배수중에 존재하는 L. casei 숙주로 하는 Lactobacillus phage J$_1$계의 분포를 조사한 결과는 다음과 같다. 1. 공장의 배수중의 J$_1$계 phage에는 Type I, II, III, IV가 존재하고 있었으며 분포순위로 보면 Type IV>Type II>Type I>Type III 이었 다. 2. 공장배수중의 phage는 역성비누를 격포하여 완전히 제거되었다. 3. 각종 소독제의 Phage에 대한 살균핵과는 염소수, 역성비누, 크레졸이 가장 강력한 효력을 나타내었고, isopropyl alcohol, ethyl alcohol등은 살균력이 미약하였다.

• Interdisciplinary Bio Central
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• 제4권3호
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• pp.9.1-9.7
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• 2012

Filamentous phages have been in the limelight as a new type of nanomaterial. In this study, genetically and chemically modified fd phage was used to generate a biomimetic phage self-assembly product. Positively charged fd phage (p8-SSG) was engineered by conjugating 3-aminopropyltriethoxysilane (APTES) to hydroxyl groups of two serine amino acid residues introduced at the N-terminus of major coat protein, p8. In particular, formation of a phage network was controlled by changing mixed ratios between wild type fd phage and APTES conjugated fd-SSG phage. Assembled phages showed unique bundle and network like structures. The bacteriophage based self-assembly approach illustrated in this study might contribute to the design of three dimensional microporous structures. In this work, we demonstrated that the positively charged APTES conjugated fd-SSG phages can assemble into microstructures when they are exposed to negatively charged wild-type fd phages through electrostatic interaction. In summary, since we can control the phage self-assembly process in order to obtain bundle or network like structures and since they can be functionalized by means of chemical or genetic modifications, bacteriophages are good candidates for use as bio-compatible scaffolds. Such new type of phage-based artificial 3D architectures can be applied in tuning of cellular structures and functions for tissue engineering studies.

• 대한수의학회지
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• 제50권4호
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• pp.285-295
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• 2010

Protein expression patterns in Salmonella enterica subspecies enterica serovar Typhimurium (S. Typhimurium) strains with diverse phenotypes, such as phage type, antibiotic resistance pattern and plasmid profiles were examined. For detailed analysis of proteins expressed by different S. Typhimurium strains, protein fractions were divided into detergent-rich phase (DP) and aqueous phase (AP) using triton X-114 detergent. The two phases were subjected to two-dimensional gel electrophoresis (2-DE), followed by protein identification using peptide mass fingerprinting (PMF). In the results, PMF showed that DP fractions consisted mainly of outer membrane proteins, whereas the AP fractions included cytosolic proteins. Comparison of 2-DE profiles of DP did not show any distinct protein spots which could be correlated with phage type, antibiotic resistance pattern or plasmid profile. However, comparisons of 2-DE profiles of the AP revealed differences in the protein spots, which could be correlated with the plasmid profile and phage types. Among these protein spots, flagellin was specific for strains containing a 90 kb plasmid. Compared to DT193 phage type, three protein spots in the range of pI 5.0-5.5 and MW 8-15 kDa of AP 2-DE profiles were absent in the DT104 phage types. Additionally, a protein spot with PI in the range of 4.5-5.0 and molecular weight (MW) between 51-69 kDa was specific for phage type DT104, while a protein spot with pI in the range of 4.0-4.8 and MW between 18-20 kDa was specific for DT193 phage type. These protein spots may be useful for discriminating phage types of S. Typhimurium.

• The Plant Pathology Journal
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• 제37권6호
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• pp.555-565
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• 2021

Bacteriophages infecting Acidovorax citrulli, the causal agent of bacterial fruit blotch, have been proven to be effective for the prevention and control of this disease. However, the occurrence of bacteriophage-resistant bacteria is one of hurdles in phage biocontrol and the understanding of phage resistance in this bacterium is an essential step. In this study, we aim to investigate possible phage resistance of A. citrulli and relationship between phage resistance and pathogenicity, and to isolate and characterize the genes involved in these phenomena. A phage-resistant and less-virulent mutant named as AC-17-G1 was isolated among 3,264 A. citrulli Tn5 mutants through serial spot assays and plaque assays followed by pathogenicity test using seed coating method. The mutant has the integrated Tn5 in the middle of a cupin protein gene. This mutant recovered its pathogenicity and phage sensitivity by complementation with corresponding wild-type gene. Site-directed mutation of this gene from wild-type by CRISPR/Cas9 system resulted in the loss of pathogenicity and acquisition of phage resistance. The growth of AC-17-G1 in King's B medium was much less than the wild-type, but the growth turned into normal in the medium supplemented with D-mannose 6-phosphate or D-fructose 6-phosphate indicating the cupin protein functions as a phosphomannos isomerase. Sodium dodecyl sulfa analysis of lipopolysaccharide (LPS) extracted from the mutant was smaller than that from wild-type. All these data suggest that the cupin protein is a phosphomannos isomerase involved in LPS synthesis, and LPS is an important determinant of pathogenicity and phage susceptibility of A. citrulli.

• 대한미생물학회지
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• 제18권1호
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• pp.39-46
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• 1983

We collected three hundred thirty-five strains of Salmonella typhi isolated from human sources during the period January to December 1982 Korea. Most of them were from general hospitals and city health center, the remaining one hundred sixtyone strains were obtained from other 12 provincial health centers among 335 testing strains. We used ninety-nine Vi-phages as distributed from International Center for Enteric phage Typing(ICEPT) in London. We found nine phage types among 335 strains of Salmonella typhi in this study. Additionally, I+IV, degraded Vi-positive and Vi negative strains were presented. This study documented the occurrence of the new $B_2$ type in Korea for the first time. The present basic phage type formula in Korea appeared to be A, $B_2,\;D_1,\;D_2,\;D_4,\;D_6,\;D_8,\;D_{12},\;E_1,\;E_9,\;D_1,\;M_1$, 40 and plus I+IV and degraded vi strains(Table 2). The current phage types of Salmonella typhi isolated in Korea 1982 were A, $B_2,\;D_1,\;D_2,\;D_6,\;D_8,\;E_1,\;M_1$ and 46 $M_1$ type was widely distributed all over the country, and E type was next predominant. Antibiotic susceptibility test were performed by means of Kirby-Bauer disc diffution method using 12 kind of antibiotics such as Ampicillin, Carbenicillin, Cephalosporin, Chloramphenicol, Colistin, Gentamicin, Kanamycin, Nalidix acid, Neomycin, Polymyxin-B, Streptomycin and Tetracycline. The sensitivity pattern to antibiotics of Salmonelia typhi cultures were summarized.

• 한국미생물·생명공학회지
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• 제19권2호
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• pp.147-152
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• 1991

In order to study effect of the phage ${\phi}$ FSV on the growth of lactic acid bacteria, Lactobacillus casei YIT 9018(wild type strain with prophage) or L. casei HYM 1213 (prophage cured strain) was infected with various concentrations of phage ${\phi}$ FSV (called Lac S21) or wild type virulent phage (called Lac J-1). When L. casei YIT 9018 was infected with Lac S21 under the concentration of $6.0{\times}10^6$ pfu/ml, the growth and lactic acid production of the strain were normal and the number of phages decreased. But L. casei HYM 1213 was susceptible to Lac S21. Regardless of the concentration of the phage infection, the number of phages increased rapidly into $10^9$ to $10^{10}$ pfu/ml at 2 day cultures and was maintained $10^7$ to $10^9$pfu/ml phage until 6 day cultures. The lactic acid production of L. casei HYM 1213 infected with Lac S21 was abnormal. Therefore, phage ${\phi}$ FSV had an evil effect on growth of L. casei HYM 1213, but not L. casei YIT 9018. On the other hand Lac J-1 caused abnormal fermentation to either L. casei YIT 9018 or L. casei HYM 1213.

• 농업과학연구
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• 제14권2호
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• pp.286-294
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• 1987

오골계 난백 lysozyme의 용균특성을 조사하고, 이를 식품보존료로 이용하기 위한 자료를 얻고자 오골계 난백으로부터 추출 분리한 lysozyme의 각종 미생물에 대한 용균성을 조사하였다. 그 결과, 공시균중 Gram 양성균인 Staphylococcus aureus phage type 29와 Bacillus subtilis ATCC 6633에 대하여는 용균성이 인정되었으나, Gram 음성균인 E. coli를 비롯한 여타의 균종과 Staphylococcus aureus phage type 57은 lysozyme에 대한 용균 감수성이 인정되지 않았다. 분리된 lysozyme은 S. aureus phage type 29를 공시균주로 하여 이를 육즙배지에 접종하고, $37^{\circ}C$에서 24시간 정치배양하여 세포를 회수한 후 540nm에서 흡광도가 0.6이 되도록 0.05M 초산완충액(pH 4.5)에 현탁시켜, 여기에 0.05%의 lysozyme을 가하여 $30^{\circ}C$, 30분간의 조건으로 반응시킬 때 용균성이 가장 좋았다. 또한 0.05%의 lysozyme은 반응액 중에 glycine(1%)을 첨가하므로서 공시균에 대한 용균효과가 양자의 상승작용에 의하여 그 단용시보다 현저히 증대(<50%) 되었으나, 기타 다른 첨가제와 금속이온 및 lysozyme과의 혼용효과는 인정되지 않았다.

• 한국동물위생학회지
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• 제24권3호
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• pp.243-253
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• 2001

Forty-five Salmonella typhimurium isolates were encountered 8 phage types in which DT197 and U302 were the predominant types. The DT104 type which was first found from pig in Korea, and was resistant to chloramphenicol, streptomycin, sulfamethoxazole/trimethoprim, tetracycline, gentamicin and nalidixic acid. Twenty-two S enteritidis isolates were encountered 5 phage types in which PT4 were the representative (predominant). S enteritidis isolates were susceptible to all antimicrobial agents. As a result of PFGE analysis for S typhimurium and S enteritidis, PFGE patterns was better than phage typing in discriminating of strains. PFGE patterns were not in accord with phage type even though some strain had the same phage types.

• Journal of Microbiology
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• 제39권3호
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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.

• Journal of Microbiology and Biotechnology
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• 제26권8호
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• pp.1473-1480
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• 2016

This study focused on the variations in the non-coding sequences between ctxB and rstR of various CTX phages. The non-coding sequences of CTX-1 and CTX-cla are phage type-specific. The length of the non-coding region of CTX-1 and CTX-cla is 601 and 730 nucleotides, respectively. The non-coding sequence of CTX phage could be divided into three regions. There is a phage type-specific Variable region between two homologous Common regions (Common regions 1 and 2). The non-coding sequence of RS1 element is similar to CTX-1 except that Common region 1 is replaced by a short RS1-specific sequence. The non-coding sequences of CTX-2 and CTX-cla are homologous, indicating the non-coding sequence of CTX-2 is derived from CTX-cla. The non-coding region of CTX-O139 is similar to CTX-cla and CTX-2; however, it contains an extra phage type-specific sequence between Common region 2 and rstR. The variations in the non-coding sequences of CTX phages might be associated with the difference in the replication efficiency and the directionality in the integration into the V. cholerae chromosome.