• 한국동물위생학회지
• /
• 제24권1호
• /
• pp.69-82
• /
• 2001

The result of studying the pathogenicity of Salmonella typhimurium and S enteritidis isolated from domestic animals in Gyeongbuk province were summarized as follows. In Congo-red binding test, S typhimurium had much more rough types than S enteritidis. In colicin production test, 4 strains of S typhimurium were positive but all of S enteritidis were negative. In hemolysin production test, all of S typhimurium and S enteritidis were negative. In Guinea pig serum resistant test, all of S typhimurium and S enteritidis were positive. As a result of pathogenicity test to mice, 54.4% of mice were died. Therefore, S typhimurium and S enteritidis were considered as highly pathogenic. S typhimurium DT104 and S enteritidis PT4 were more pathogenic to mice than other phage types of same serovar. S typhimurium and S enteritidis were considered not so pathogenic for 6-day-old chickens. The recovery rates of Salmonella stains from mice and chickens inoculated were 96.8%, and 54%, respectively. In chickens, proportional to the time from 2 weeks after challenge inoculation, the recovery rates were noticeably decreased.

• Journal of Microbiology and Biotechnology
• /
• 제19권9호
• /
• pp.898-903
• /
• 2009

Pullorum disease affecting poultry is caused by Salmonella enterica serovar Pullorum and results in severe economic loss every year, especially in countries with a developing poultry industry. The pathogenesis of S. Pullorum is not yet well defined, as the specific virulence factors still need to be identified. Thus, to isolate specific DNA fragments belonging to S. Pullorum, this study used suppression subtractive hybridization. As such, the genome of the S. Pullorum C79-13 strain was subtracted from the genome of Salmonella enterica serovar Gallinarum 9 and Salmonella enterica serovar Enteritidis CMCC(B) 50041, respectively, resulting in the identification of 20 subtracted fragments. A sequence homology analysis then revealed three types of fragment: phage sequences, plasmid sequences, and sequences with an unknown function. As a result, several important virulence-related genes encoding the IpaJ protein, colicin Y, tailspike protein, excisionase, and Rhs protein were identified that may play a role in the pathogenesis of S. Pullorum.

• Journal of Microbiology and Biotechnology
• /
• 제21권1호
• /
• pp.50-54
• /
• 2011

This study's objective was to determine the prevalence of Salmonella spp. in pigs and their farm environments in Korea, and to investigate the relationship between the strains based on their phenotypic and genotypic characteristics. A total of 36 Salmonella spp. were isolated in this study: 18 isolates from 492 pigs (3.7%) and 18 isolates from 418 (4.3%) farmhouse environmental samples from 16 different pig farms. Of the Salmonella strains isolated from the numerous environmental samples, the highest prevalence was observed in slurry or manure, followed by partitions, farmer's hands, floors, water/nipples, ventilation sources, and feed, respectively. All the Salmonella isolates originating from different farms were genetically distinct. In three farms, however, identical phage types and pulse-field gel electrophoresis patterns were observed among Salmonella isolates from pig feces and environmental samples. This study suggests that environments contaminated with Salmonella could pose an infection risk to pigs on pig farms.

• Current Optics and Photonics
• /
• 제1권1호
• /
• pp.12-16
• /
• 2017

Color sensor systems based on M13 bacteriophage are being considerably researched. Although many studies on M13 bacteriophage-based chemical sensing of TNT, endocrine disrupting chemicals, and antibiotics have been undertaken, the fundamental physical and chemical properties of M13 bacteriophage-based nanostructures require further research. A simple M13 bacteriophage-based colorimetric sensor was fabricated by a simple pulling technique, and M13 bacteriophage was genetically engineered using a phage display technique to exhibit a negatively charged surface. Arrays of structurally and genetically modified M13 bacteriophage that can determine the polarity indexes of various alcohols were found. In this research, an M13 bacteriophage-based color sensor was used to detect various types of alcohols, including methanol, ethanol, and methanol/butanol mixtures, in order to investigate the polarity-related property of the sensor. Studies of the fundamental chemical sensing properties of M13 bacteriophage-based nanostructures should result in wider applications of M13 bacteriophage-based colorimetric sensors.

• BMB Reports
• /
• 제36권5호
• /
• pp.493-498
• /
• 2003

The scFv antibody towards the Burkholderia pseudomallei exotoxin was previously constructed by phage display and exhibited good specificity towards the exotoxin. We report here the optimization of the scFv expression in an E. coli expression system. Four different E. coli strains (ER2537, TG1, HB2151, and XL1-Blue) were examined for optimal expression of the scFv protein. Two types of carbon source (i.e. 0.2% glucose and 0.2% glycerol) were also tested for their ability to induce the scFv expression. Cells that carried the scFv construct were grown at $30^{\circ}C$ and induced with 0.05 mM IPTG. The expression was then monitored by SDS-PAGE, Western blotting, and indirect ELISA. The Western blot profile showed different levels of the scFv expression among the host strains; XL1-Blue exhibited the highest level of the scFv protein expression. Glycerol at a concentration of 0.2% (v/v) significantly increased the scFv protein expression level when compared to 0.2% (w/v) glucose. Further optimization demonstrated that the scFv protein expression in XL1-Blue was the most optimal with a glycerol concentration as low as 0.05%. However, by indirect ELISA, only the scFv protein that was expressed in 0.2% (v/v) glycerol exhibited high specificity towards the Burkholderia pseudomallei exotoxin.

• 한국미생물·생명공학회지
• /
• 제14권4호
• /
• pp.319-324
• /
• 1986

Lactobacillus casei 모세포와 동종간 융합세포간의 유산생성, 단백질 분해력, Bacteriophage 저항성 등의 생리적 특성과 표현형을 비교분석하였다. 두 모세포 사이에서 형성된 융합세포는 모세포를 침입하는 bacteriophage에 대하여 저항성을 시험한 결과 L. casei C-M 표현형은 융합세포 중 46%를 차지하였고, L. casei 3-M 표현형은 42%였고, 12%의 융합세포는 두 모세포 bacteriophage에 저항성을 소유하였다. 융합세포의 유산생성력과 단백질 분해력도 유사한 출현율을 나타내었다. Plasmid DNA의 Hind III 분해물은 모세포와 융합세포간에 차이가 없었으나, 융합세포들은 L. casei C-M 또는 L. casei 3-M 중 어느 한 모세포의 Plasmid만을 소유하고 있었다.

• 한국식물학회:학술대회논문집
• /
• 한국식물학회 1996년도 식물학심포지움 식물호르몬과 신호전달
• /
• pp.68-78
• /
• 1996

Two types of immunoloigcal probes, anti-ABBP Abs, have been developed. The purified ABBP from ABA-C1-BSA-sepharose 4B column was identified by PAGE and appeared in one band of about 56KD, as well as showed a specific binding ability and a high affinity for ABA (Kd2.0$\times$10-9 mol/L). Unexpectedly, the existence of rRNA with a length of around 300 nucleotides could be found, when the ABBP was digested with proteinase K and identified by eletrophorsis on an agarose gel (1%). As a result, about 120 cDNA clones coding maize 17s RNA and only one cDNA clone coding ABBP (24cDNA) were obtained from 200,000 seperated phage plaques by the anti-ABBP pAbs. 24cDNA had 1075bp and contained an open reading frame coding 254 amino acids. The anti-idiotypic Ab raised against an ABA MAb showed the ability of either mimicking ABA or competing with ABA. The localization of ABBPs in plant cell was investigated.

• 미생물학회지
• /
• 제17권4호
• /
• pp.165-178
• /
• 1979

Phages of Lactobaciilus casei (PLC) isolated from plant drainage were classified and characterized. The results are as follows : 1. On the basis of host range pattern, phages could be divided into 2 groups (PLC-B and PLC-C). PLC-B group phages could be further divided into 5 sub-groups $(B_1, \;B_2, \;B_3, \;B_4, \;and\;B_5)$. Although PLC-C group phages had the same host range, they could be also divided into 2 sub-groups $(C_1\;and\;C_2)$ by morphlogical type. 2. It was $B_3$ group phages that represented a major proportion (44.4%) of phages tested. However, $B_1$ group phages were shown to have the widest host range. 3. Electron micrographs revealed that the phages fell into three different morphological types. $(B_1, \;B_2, \;and\;B_3)$ group phages hd a hexagonal head (52nm in diameter) and a sheathless noncontractile (245 nm in length). $B_4\;and\;C_2$ group phages had a hexagonal head (56 nm) and a short flexible tail (169nm) having no sheath. $B_5\;and\;C_1$ group phages were shown to have a hexagonal head (81 nm) and a contractile tail (140 nm) having a sheath, a base plate and tail fibers. 4. The inactivation of the phages by antisera indicated that serological relationships correlated completely with morphological types. 5. $B_1, \;C_1\;and\;C_2$ group phages produced a large (1, 2 mm in diameter) plaque with a clear ring. The morphology of plaques of $B_3\;and\;B_5$ group phages was the same as those produced by the above, but the average plaque sizes for $B_3\;and\;B_5$ were 0.8 mm abd 0.5 mm, respectively. $B_2\;and\;B_4$ group phages produced a small (0.5 mm) turbid plaque with an irregular edge. 6. The latent period and the average burst size of $B_1\;and\;B_3$ group phages were 90 min and 100, respectively. These phages reuqired calcium ions for their miltiplication. 7. $B_3$ group phages could not be absrobed to R-variant $KC_1$. 8. The order of resistance of phages to heat was $B_2\;>\;B_1, B_4\;and\;B_5\;>\;B_3\;and\;C_2, \;B_5$ group phages were more stable than $B_3$ in various pH values. $C_2$ group phages were more sensitive to UV irradiation than $B_1\;and\;B_3$ group phages. 9. Strains YIT9018 and IAM 1043 were induced by mitomycin C treatment. Phage particles detected in the lysates had a hexagonal head (38 and 49 nm, respectively), but no tail. Any sensitive indicator strain could not be isolated in spite of repaeated trials.

• 대한미생물학회지
• /
• 제21권1호
• /
• pp.73-95
• /
• 1986

A total of 5,462 isolates suspicious of Salmonella, Shigella and E. coli which were isolated during 1983 to 1985 by 12 City Hygine Laboratories and General Hospital Laboratories were received and identified at the National Salmonella Center, Seoul, Korea. The result of identification of these strains were summarized as follows: 1. It was confirmed that the total organisms broke down into 2,014 strains of Salmonella 1,294 of which were S. typhi, 887 strains of Shigella and 2,561 strains of E. coli. 2. For seasonal distribution of enteric pathogens, July was the month with the highest out breaks of salmonellosis, May was the month of Shigellosis, and April was of the highest month it in the case of E. coli. 3. Salmonella typhi with the highest incidence of isolation was shown to belong to various phage types, especially with the strains detected in Seoul. M1 type was widely distributed all over the country, but the majority was E1 type in 1983. 4. For age distribution of patients, the 20-29 age group had the highest incidence of salmonellosis whileas the 1 to 9 age group had the highest incidence of Shigellosis. 5. For sexuly distribution of Salmonella and Shigella infections seemed to be relatively higher in the female than in the male. However, E. coli. had no relationship to both sex. 6. The antibiotic sensitivity patterns of S. typhi cultures showed a tendancy to be resistant to colistin, gentamycin, neomycin, tetracycline and streptomycin. 7. The isolates of S. paratyphi-A, S. typhimurium and S. enteritidis seemed to have a tendency of multiple drug resistance. 8. 93.9 percent of 1,568 E. coli strains showed negative reactions to the antisera of enteropathogenic E. coli and 15.6 percent of them produced a heat-labile enterotoxin, but positive reaction to the antisera was 6.1 percent and 11.6 percent of them producled the enterotoxin.

• 생명과학회지
• /
• 제26권2호
• /
• pp.265-274
• /
• 2016

Toxin-antitoxin (TA) system은 박테리아와 고세균에서 진화적으로 보존되어 흔히 발견되는 유전적 모듈이다. 기본적으로 이 시스템은 세포 내 toxin과 그들의 억제자로 작용하는 antitoxin으로 구성되어있으며, 현재 총 다섯가지 유형으로 구분된다. 공통적으로 toxin은 스트레스 조건에서 활성화됨으로써 세포 내 다양한 과정을 억제하는 활성을 가지는데 이는 결과적으로 세포 사멸 혹은 가역적인 생장 저해를 일으킨다. Toxin의 이러한 효과들은 유전자 발현의 조절, 성장 조절, programmed cell arrest, programmed cell death, persister cell의 형성, 박테리오파지 방어기작, 가동성 유전인자의 안정화, 플라스미드 유지 기작 등 다양한 생리학적 역할을 나타낸다. 그러므로 TA system은 일반적인 스트레스 반응모듈로서 여겨진다. 하지만 이를 역이용한다면 TA system으로부터 toxin을 활성화 시키는 인자를 개발하여 새로운 항균 물질로 이용할 수 있다. 그뿐만 아니라 TA system은 toxin의 세포 사멸 효과를 이용하여 원하는 타겟 유전자가 존재하는 세포만 선택적으로 살아남도록 하는 효율적인 클로닝 전략에 이용될 수 있다. 또한, toxin의 서열 특이적 리보핵산 가수분해효소 활성을 이용하여 타겟 단백질 이외의 단백질 합성을 막아 효과적인 단일 단백질 대량 생산을 위해서도 이용할 수 있다. 더 나아가 일부 TA system의 toxin은 진핵 세포에서도 세포 독성을 나타내기 때문에 암세포, 바이러스 감염 세포에서 toxin의 발현을 유도하여 세포사멸을 일으킴으로써 인간의 질병 치료로 이어질 수 있다.