• 미생물학회지
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• 제39권4호
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• pp.277-282
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• 2003

P2의 sir 변이를 억제하는 변이체 박테리오파아지 P4를 얻기 위하여, P4 ash8 sid71 kmr intS를 박테리오파아지 P2 sir3 용원소에 plating하여 플라크를 형성하는 P4 ost2를 분리하였다. P4 ost2는 1단계 생장실험에서 P2의 sir 변이를 억제하는 P4 변이체로 나타났다. 제한효소 절단 반응으로 유전체 DNA의 재배열이 일어난 단편을 찾아 cloning과 sequencing을 거쳐 P4 ost2의 구조를 규명하였다. P4 ost2의 DNA는, 6.9 kb의 결실을 가진 P4 ash8 sid71 kmr intS의 불완전한 trimer로 2개의 cos-cleavage 부위를 가지는 28.8 kb의 유전체로 밝혀졌다. CsCl 부양균등밀도 편차실험으로 P4 ost2의 DNA 크기를 확인하였고 파아지 머리 안에 packaging된 DNA에 대한 기초적인 구조를 파악하였다. P4 ost2의 분리 동정을 통해, P4 유전체 상의 cos-cleavage 부위의 개수가 Sir-type 파아지 머리의 packaging 반응과는 관련이 없다고 추정할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권3호
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• pp.386-393
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• 2013

This experiment was conducted to evaluate anti-Salmonella enteritidis (anti-SE) bacteriophage as feed additives to prevent Salmonella enteritidis in broilers. The experimental diets were formulated for 2 phases feeding trial, and 3 different levels (0.05, 0.1 and 0.2%) of anti-SE bacteriophage were supplemented in basal diet. The basal diet was regarded as the control treatment. A total of 320 1-d-old male broilers (Ross 308) were allotted by randomized complete block (RCB) design in 8 replicates with 10 chicks per pen. All birds were raised on rice hull bedding in ambient controlled environment and free access to feed and water. There were no significant differences in body weight gain, feed intake and feed conversion ratio (FCR) at terminal period among treatments (p>0.05). Relative weights of liver, spleen, abdominal fat and tissue muscle of breast obtained from each anti-SE bacteriophage treatment were similar to control, with a slightly higher value in anti-SE bacteriophage 0.2%. In addition, a numerical difference of glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT) and LDL cholesterol level was observed in the 0.2% anti-SE bacteriophage application even though blood profiles were not significantly affected by supplemented levels of anti-SE bacteriophage (p>0.05). In the result of a 14 d record after Salmonella enteritidis challenge of 160 birds from 4 previous treatments, mortality was linearly decreased with increasing anti-SE bacteriophage level (p<0.05), and Salmonella enteritidis concentration in the cecum was decreased with increasing levels of anti-SE bacteriophage (p<0.05). Based on the results of this study, it is considered that supplementation of 0.2% anti-SE bacteriophage may not cause any negative effect on growth, meat production, and it reduces mortality after Salmonella enteritidis challenge. These results imply to a possible use of anti-SE bacteriophage as an alternative feed additive instead of antibiotics in broilers diet.

• Journal of Microbiology
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• 제44권5호
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• pp.530-536
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• 2006

Bacteriophage P4, a satellite phage of coliphage P2, is a very useful experimental tool for the study of viral capsid assembly and cos-cleavage. For an in vitro cos-cleavage reaction study of the P2-P4 system, new shortened and selectable markers containing P4 derivative plasm ids were designed as a substrate molecules. They were constructed by swapping the non-essential segment of P4 DNA for either the kanamycin resistance (kmr) gene or the ampicillin resistance (apr) gene. The size of the genomes of the resulting markers were 82% (P4 ash8 delRI:: kmr) and 79% (P4 ash8 delRI:: apr) of the wild type P4 genome. To determine the lower limit of genome size that could be packaged into the small P4-size bead, these shortened P4 plasmids were converted to phage particles with infection of the helper phage P2. The conversion of plasmid P4 derivatives to bacteriophage particles was verified by the heat stability test and the burst size determination experiment. CsCl buoyant equilibrium density gradient experiments confirmed not only the genome size of the viable phage form of shortened P4 derivatives, but also their packaging into the small P4-size head. P4 ash8 delRI:: apr turned out to be the smallest P4 genome that can be packaged into P4-sized head.

• Asian-Australasian Journal of Animal Sciences
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• 제25권7호
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• pp.1015-1020
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• 2012

An experiment was conducted to evaluate the effects of bacteriophage supplementation on egg performance, egg quality, excreta microflora, and moisture content in laying hens. A total of 288 Hy-line brown commercial laying hens (36-wk-old) were randomly allotted to 4 treatments in this 6-wk trial and dietary treatments included: i) CON, basal diet; ii) T1, CON+0.020% bacteriophage; iii) T2, CON+0.035% bacteriophage; iv) T3, CON+0.050% bacteriophage. There were 6 replicates for each treatment with 6 adjacent cages (2 hens/cage). Laying hens in T2 and T3 treatments had higher (p<0.05) egg production than those in CON and T1 treatments during wk 0 to 3. In addition, egg production in T1, T2, and T3 treatments was increased (p<0.05) compared with that in CON treatment during wk 4 to 6. At wk 4 and 5, birds in T2 group had higher (p<0.05) HU than those in CON. In addition, at wk 5 and 6, HU in birds fed T1 and T3 diets was greater (p<0.05) than those fed CON diet. E. coli and Salmonella spp. concentrations in excreta were decreased (p<0.05) by T1, T2, and T3 treatments. However, egg weight, egg shell color, yolk height, yolk color unit, egg shell strength, egg shell thickness, egg gravity, and excreta moisture content were not influenced by dietary treatments during the entire experimental period. In conclusion, bacteriophage supplementation has beneficial effects on egg production, egg albumen, and excreta microflora concentration in laying hens.

• Journal of Microbiology and Biotechnology
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• 제11권4호
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• pp.724-726
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• 2001

The growth of baceriophage T4 is inhibited by the presence of the tin gene product o bacteriophage P2. The interaction between purified Tin and gp32 proteins was observed using coimmunoprecipitation experiments. The in vivo interaction was confirmed by yeast two-hybrid experiments. A deletion analysis showed that the Asp 163 region of gp32 to DNA substrates was not affected by the presence of Tin, Thus, it would appear that the inhibition of 4 growth by Tin was due to a protein-protein interaction rather than affecting the DNA-binding ability of gp32.

• 미생물학회지
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• 제39권2호
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• pp.118-122
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• 2003

바이러스 조립 과정 기작 연구를 위한 좋은 재료인 박데리오파아지 P2-P4시스템에 이용될 벡터 플라스미드를 개발하기 위하여, P4 ash8 sid71을 출발 물질로 삼아 새로운 P4 유도체 벡터를 조성하였다. 유전자 재조합 기법을 써서 쉽게 선택 가능한 tetracyclin내성 유전자(tetR)를 도입하고 플라스미드P 4의 크기를 조절하였다. 이를 통해 얻어진 P4 ash8(sid7l) tetR은 12.09 kb의 크기를 가지며, 필요할 때 P2로 induction하면 생물학적 활성을 가지는 박데리오파아지로 전환 가능하였다. 전환된 파아지의 burst size를 결정하고, CsCi 부양균등밀도 편차실험을 수행하였다. 균등밀도 실험 분포도에서 P2크기 파아지 머리의 packaging 상한을 추정할 수 있었다.

• Journal of Animal Science and Technology
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• 제66권2호
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• pp.340-352
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• 2024

This study measured the potential changes of the microbiota in the gastrointestinal tract and energy and nutrient digestibility by supplemental bacteriophages in pigs. Twelve castrated male pigs (initial mean body weight = 29.5 ± 2.3 kg) were surgically cannulated using T-cannula. The animals were housed individually in pens equipped with a feeder and a nipple waterer. The pigs were allotted to 1 of 3 experimental diets in a quadruplicated 3 × 2 Latin square design with 3 experimental diets, 2 periods, and 12 pigs resulting in 8 replicates per diet. The 3 diets were a control mainly based on corn and soybean meal with no antibiotics or bacteriophages, a diet containing 0.1% antibiotics, and a diet containing 0.2% bacteriophages. On day 5 of the experimental period, feces were collected and on days 6 and 7, ileal digesta were collected. Genomic DNA for bacteria were extracted from the ileal digesta and feces and the V4 region of the 16S rRNA gene was amplified. The ileal and fecal digestibility of energy, dry matter, organic matter, crude protein, and fiber was unaffected by dietary antibiotics or bacteriophages. At the phylum level, the supplemental antibiotic or bacteriophage tended to result in a higher proportion of Firmicutes (p = 0.059) and a lower proportion of Bacteroidetes (p = 0.099) in the ileal digesta samples compared with the control group with no difference between the antibiotic and bacteriophage groups. At the genus level, the supplemental antibiotic or bacteriophage tended to result in a higher proportion of Lactobacillus (p = 0.062) and a lower proportion of Bacteroides (p = 0.074) and Streptococcus (p = 0.088) in the ileal digesta compared with the control group with no difference between the antibiotic and bacteriophage groups. In the feces, supplemental antibiotics or bacteriophages reduced the proportion of Bifidobacterium compared with the control group (p = 0.029) with no difference between the antibiotic and bacteriophage groups. Overall, supplemental antibiotics and bacteriophages showed positive effect on the microbiota of in the ileal digesta without largely affecting energy or nutrient digestibility, with no differences between the antibiotic and bacteriophage groups in growing pigs.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.272-274
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• 2000

Temperate bacteriophage P2 has a nonessential gene called old(overcoming lysoginization defection). In the presence of old, the growth of the host (Escherichia coli) with recBC- genotype is ingibited, and another bacteriophage, lambda, cannot superinfect. The Old protein has been shown to possess an exonuclease actibity. Three mutant P2s(old 1, old 17, old 49) which did gene was coned into expression vectors to produce hexahistidine-tagged proteins. The proteins were affinity-purified and shown to lose its exonuclease activity on both double-stranded and single-stranded DNA substrates. Thus, it was concluded that the lambda exclusion was related to Old's exonuclease activity.

• Asian-Australasian Journal of Animal Sciences
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• 제26권4호
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• pp.573-578
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• 2013

A total of 720 1-d-old male broilers (Arbor Acres) with the initial BW = $45{\pm}2$ g were used in a 32-d experiment. Birds were randomly allotted into 1 of 4 treatments according to a completely random block design. Dietary treatments included: i) CON (basal diet), ii) ANT (CON+0.5 g antibiotics/kg feed (bacitracin methylene disalicylate)), iii) BP1 (CON+0.25 bacteriophage/kg feed), and iv) BP2 (CON+0.5 g bacteriophage/kg feed). The BWG and FI were not affected by dietary treatments throughout the whole experiment, whereas BP2 treatment reduced (p<0.05) the feed conversion ratio compared with the CON treatment during 0 to 14 d. The birds fed bacteriophages at the level of 0.25 g/kg increased (p<0.05) the relative liver weight. The inclusion of antibiotic and bacteriophage significantly reduced (p<0.05) the Escherichia coli and Salmonella concentration in the excreta compared with the NC group. Broilers fed the BP2 treatment had higher (p<0.05) lactobacillus counts compared with those fed NC and PC treatments. In conclusion, dietary supplementation of 0.5 g/kg bacteriophages increased feed efficiency and liver weight without effects on the breast muscle properties; also pathogens were inhibited by addition of bacteriophages.

• The Plant Pathology Journal
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• 제31권1호
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• pp.83-89
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• 2015

In order to control Pectobacterium carotovorum subsp. carotovorum, a novel virulent bacteriophage PM2 was isolated. Bacteriophage PM2 can infect 48% of P. carotovorum subsp. carotovorum and 78% of P. carotovorum subsp. brasilliensis but none of atrosepticum, betavasculorum, odoriferum and wasabiae isolates had been infected with PM2. PM2 phage belongs to the family Myoviridae, and contains a large head and contractile tail. It has a 170,286 base pair genome that encodes 291 open reading frames (ORFs) and 12 tRNAs. Most ORFs in bacteriophage PM2 share a high level of homology with T4-like phages including IME08, RB69, and JS98. Phylogenetic analysis based on the amino acid sequence of terminase large subunits confirmed that PM2 is classified as a T4-like phage. It contains no integrase- or no repressor-coding genes related to the lysogenic cycle, and lifestyle prediction using PHACT software suggested that PM2 is a virulent bacteriophage.