• Microbiology and Biotechnology Letters
• /
• v.5 no.1
• /
• pp.13-17
• /
• 1977

We isolated lactobacillus phage hosting L. casei strains, and examined distribution of the phages and resistance to the sanitary reagent treatment in drainages fo Korea plant. 1) There were Type 1, 11, 111, and 1v of the phage J$_1$in plantdrainages and the order of distribution was Type 1v>Type 11>Type 1>$^1$Type 111. 2) All the phages in plantdrainages were completely removed by spreading the invert soap. 3) Sodium hypochloride, invert soap and dresol were most effective sanitary reagents, and isopropyl alcohol and ethyl alcohol were sanitary reagents.

• Interdisciplinary Bio Central
• /
• v.4 no.3
• /
• pp.9.1-9.7
• /
• 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.

• Korean Journal of Veterinary Research
• /
• v.50 no.4
• /
• pp.285-295
• /
• 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
• /
• v.37 no.6
• /
• pp.555-565
• /
• 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.

• The Journal of the Korean Society for Microbiology
• /
• v.18 no.1
• /
• pp.39-46
• /
• 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.

• Microbiology and Biotechnology Letters
• /
• v.19 no.2
• /
• pp.147-152
• /
• 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.

• Korean Journal of Agricultural Science
• /
• v.14 no.2
• /
• pp.286-294
• /
• 1987

This experiment was carried out to investigate the bacteriolytic action of the egg white lysozyme isolated from Korean native Ogol fowl and to obtain the data for utilization of the enzyme as a food preservative. Staphyococcus aureus phage type 29 and Bacillus subtilis ATCC 6633 among the microorganisms tested were lyzed by the treatment with 0.05% lysozyme, but Staphylococcus aureus phage type 57 in addition to E. coli etc. was found to be a lysozyme- insensitive species. The lysis of S. aureus phage type 29 was maximized when incubated in nutrient broth (pH 7.0) at $37^{\circ}C$ for 24 hours and suspended it to absorbance 0.6 at 540nm in 0.05M sodium acetate but fer (pH 4.5) and then treated it with the 0.05% lysozyme for 30 min. at $30^{\circ}C$. It was found that the effect of 0.05% lysozyme in combination with 1% glycine on the growth inhibition of S. aurecus phage type 29 increased more 50% than that in the absence of glycine, but not effect with other any additeves and metal ions tested.

• Korean Journal of Veterinary Service
• /
• v.24 no.3
• /
• pp.243-253
• /
• 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
• /
• v.39 no.3
• /
• pp.219-225
• /
• 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
• /
• v.26 no.8
• /
• pp.1473-1480
• /
• 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.