• 한국환경보건학회지
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• 제39권5호
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• pp.465-473
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• 2013

Objectives: This study was undertaken to analyze Staphylococcus aureus from cultivation environments for agricultural products and to confirm antibiotic resistance and enterotoxin genes for the isolated S. aureus. Methods: A total of 648 samples were collected from apple, peach, ginseng and balloon flower farms. S. aureus was isolated from soil, agricultural water, personal hygiene elements (hands, gloves and clothes) and work utensils (boxes). Results: S. aureus was detected in a total of 25 samples and 72 strains were isolated. The resistance rate of the isolated S. aureus strains was confirmed at 33.3%, with 24 resistant strains among the total of 72. Fourteen different patterns types were found, and three pattern types (NV, OX, VA) were confirmed most frequently. As result of the detection of enterotoxin gene type, four gene types (sea: 1, sed: 4, seg: all isolated S. aureus, sei: all isolated S. aureus) were analyzed among a total of nine types. Conclusions: This study demonstrates that personal hygiene techniques should be properly managed, such as washing and sterilization before or after work, because agricultural contamination by S. aureus frequently developed through improper management.

• Journal of Veterinary Science
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• 제25권1호
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• pp.12.1-12.10
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• 2024

Background: Staphylococcus aureus and S. pseudintermedius are the major etiological agents of staphylococcal infections in humans, livestock, and companion animals. The misuse of antimicrobial drugs has led to the emergence of antimicrobial-resistant Staphylococcus spp., including methicillin-resistant S. aureus (MRSA) and methicillin-resistant S. pseudintermedius (MRSP). One novel therapeutic approach against MRSA and MRSP is a peptide nucleic acid (PNA) that can bind to the target nucleotide strands and block expression. Previously, two PNAs conjugated with cell-penetrating peptides (P-PNAs), antisense PNA (ASP)-cmk and ASP-deoD, targeting two essential genes in S. aureus, were constructed, and their antibacterial activities were analyzed. Objectives: This study analyzed the combined antibacterial effects of P-PNAs on S. aureus and S. pseudintermedius clinical isolates. Methods: S. aureus ATCC 29740 cells were treated simultaneously with serially diluted ASP-cmk and ASP-deoD, and the minimal inhibitory concentrations (MICs) were measured. The combined P-PNA mixture was then treated with S. aureus and S. pseudintermedius veterinary isolates at the determined MIC, and the antibacterial effect was examined. Results: The combined treatment of two P-PNAs showed higher antibacterial activity than the individual treatments. The MICs of two individual P-PNAs were 20 and 25 µM, whereas that of the combined treatment was 10 µM. The application of a combined treatment to clinical Staphylococcus spp. revealed S. aureus isolates to be resistant to P-PNAs and S. pseudintermedius isolates to be susceptible. Conclusions: These observations highlight the complexity of designing ASPs with high efficacy for potential applications in treating staphylococcal infections in humans and animals.

• 한국식품과학회지
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• 제43권6호
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• pp.791-794
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• 2011

본 연구는 그람 양성균과 음성균인 S. aureus와 S. Typhimurium를 대상으로 시트랄의 농도와 pH에 따른 항균활성 특성 및 식품 적용 가능성을 조사하였다. 농도별 항균활성은 TSB에 시트랄을 0-1,000 ppm 농도로 처리하였으며, pH는 buffer를 이용하여 pH 4.0에서 pH 7.0로 조정하여 측정하였다. 시트랄 농도 별 항균활성 실험에서는 두 균주 모두 시트랄 농도가 높아질수록 항균활성이 증가하였다. S. Typhimurium는 250 ppm 처리구에서 대조구와 유의적 차이가 없었으나 S. aureus는 약 3 log 수준으로 감소되었다. pH에 따른 항균활성은 10분이 경과 후 S. aureus는 약 1-2 log의 감소효과를, S. Typhimurium는 약 2-5 log의 감소효과를 나타내었다. TSB와는 다르게 buffer 조건에서 그람 양성 균주인 S. aureus는 S. Typhimurium와 비교하여 pH 조건에 안정적인 경향을 나타내었다. 녹즙에 적용한 시트랄은 그람 음성균인 S. Typhimurium에 대한 항균활성은 미미하였으나 양성균인 S. aureus 에 대하여 농도가 증가할수록 효과적으로 항균활성이 증가하였다.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.137-142
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• 2000

Environmental stres is known to induce heat shock proteins (HSPs) in eukaryotic cells. However, the induction of HSPs in host cells by microbial infection has not yet been well explained. Staphylococcus aureus (S. aureus) is one of the major pathogens in the pathogenesis of endovascular diseases such as infective endocarditis. In this study, the synthesis of stress-inducible 70 kDa HSP was investigated in the endothelial cells (ECs) after 3 h to 20 h of incubation with S. aureus. The dffect of S. aureus infection on the expression of HSP70 in cultured ECs was analyzed using laser scanning confocal microscopy (LSCM). The increase of HSP70 expression in ECs infected by S. aureus ($10^4{\;}cfu/ml$) for 20 h was 1.1-fold higher than that in heat shock treated ECs and 2.2-fold higher than that in untreated cells. Heat shock is known to induce intranucleus HSP70 expression in mammalian cells, whereas the S. aureus infection induced perinuclear expression in ECs as observed by LSCM. Consequently, the expression of HSP70 in ECs plays an important role in the pathogenesis of endovascular infection.

• 대한방사선기술학회지:방사선기술과학
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• 제45권2호
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• pp.165-170
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• 2022

Staphylococcus aureus is a major pathogen that causes clinical infections in humans and can also cause massively colonized in lesion skin, particularly in atopic dermatitis patients. This study investigated the effects of photodynamic inactivation with radachlorin and diode laser irradiation on the viability of S. aureus in vitro and assessed the effects of the dose of laser transmission. In the PDI group, 5 𝜇L of S. aureus suspension and 5 𝜇L of radachlorin were inoculated in a 55 mm petri dish (63.6 cm²). The samples were placed in a 37° incubator for 30 min and then irradiated with light (660 nm diode laser). After laser irradiation, the cells were stored for 24 h at 37° in an incubator with 5% CO2, and the number of colonies was counted. All CFU/mL of S. aureus were reduced by diode laser in the presence of radachlorin, with a killing rate of 87.9% at an energy dose of 9 J/cm². This study contribute to treat colonized with S. aureus in atopic dermatitis patients and wound infections by providing information on the optimal dose of laser transmission using PDI to eliminate S. aureus.

• 대한임상검사과학회지
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• 제40권1호
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• pp.48-54
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• 2008

Multiplex-PCR을 이용하여 대구와 경상북도 내의 다양한 입원 환자들로부터 분리된 187주의 MRSA 균주를 재료로 9가지 종류의 내독소(sea~see, seg~sej ), 3종류의 병독소(eta, etb, tst ) 그리고 내부 양성 지표로써 16S rRNA와 MecA 유전자를 검출하였다. S. aureus 균주에서 새로운 형태의 내독소 유전자(seg~sej)의 빈도가 65.9%로 매우 높게 잠복하고 있었으며, 고전적 형태의 내독소 유전자(sea~see)도 47.8%로 선행 연구에서 검출된 것만큼 높게 잠복하고 있었다. 새로운 형태의 내독소 중 쌍을 이룬 형태(즉, sec+seg+sei, seg+sei)는 많이 검출된 반면 단일 형태의 내독소(즉, seg, seh, sei, sej)는 거의 검출되지 않았거나 없었으며, 쌍을 이룬 내독소 유전자를 가진 S. aureus는 잠재적으로 보다 더 독성균주가 될 것으로 판단된다. 더 나아가 S. aureus 균주들 사이의 높은 보유율을 보이는 seg와 sei 사이의 체계적인 관련성은 staphylococcal enterotoxin들 사이에 중요한 계통발생적 연계가 있을 수 있다는 것은 암시한다.

• 대한수의학회지
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• 제37권4호
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• pp.875-882
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• 1997

To produce the recombinant fibronectin-binding protein(FnBP) for development of subunit vaccine against Staphylococcus aureus. The fnbp gene was amplified from the chromosomal DNA of S aureus KNU 196 strain using the polymerase chain reaction, and cloned into pGEX-4T-2. Then, the recombinant FnBP fused with glutathione-S-transferase was produced in E coli, purified by affinity chromatography, and identified its antigenicity and immunogenicity by Western blot. The recombinant FnBP produced in this study is considered to have the same property of native FnBP purified from S aureus, and is expected to be useful as a candidate for S aureus subunit vaccine.

• 대한수의학회지
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• 제54권1호
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• pp.49-52
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• 2014

This study was conducted to compare the patterns of mastitic pathogens and the antimicrobial susceptibility of Staphylococcus (S.) aureus from conventional milking (CM) and robotic milking (RM) dairy herds. To accomplish this, the minimum inhibitory concentrations of 14 antimicrobial agents were tested against S. aureus by the microdilution method. Regardless of the milking system, S. aureus, coagulase negative staphylococcus, and Streptococcus uberis were isolated. Additionally, significant differences in the antimicrobial susceptibility of S. aureus isolates between RM and CM farms were only observed in response to tetracycline.

• 대한약침학회지
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• 제10권3호
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• pp.71-76
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• 2007

Objectives This experimental study was performed to investigate the continuous anti-bacterial potency of Coptidis rhizoma extract on cultivation of Staphylococcus species(S. aureus, S. epidermidis) that induce eye disease. Methods Minimal inhibitory concentration(MIC) was measured by dropping to $50{\mu}l$ diluted Coptidis rhizoma extract(100%, 10%, 1%, 0.1%) on S. aureus, S. epidermidis that were cultivated from 2 to 6 days. Anti-bacterial potency was measured by the size of inhibition zone with change of volume($20{\mu}l,\;30{\mu}l,\;40{\mu}l,\;50{\mu}l$). Results 1. Anti-bacterial potency of Coptidis rhizoma extract on S. aureus was appeared in 100%, 10% and was the same as anti-bacterial potency of 2 days and 6 days. Anti-bacterial potency with change of volume(100%) was increased in propotion to increase volume on all samples. Anti-bacterial potency with change of volume(10%) was increased in propotion to increase volume on all samples except $20{\mu}l$. Anti-bacterial potency of Coptidis rhizoma extract on S. aureus was appeared continuous. 2. Anti-bacterial potency of Coptidis rhizoma extract on S. epidermidis was appeared in 100%, 10% and was the same as anti-bacterial potency of 2 days and 6 days. Anti-bacterial potency with change of volume(100%) was increased in propotion to increase volume on all samples. Anti-bacterial potency with change of volume(10%) was appeared in $50{\mu}l$. Anti-bacterial potency of Coptidis rhizoma extract on S. epidermidis was appeared continuous. Conclusions Anti-bacterial potency of Coptidis rhizoma extract on cultivation of S. aureus & S. epidermidis was showed continuous.

• 대한약침학회지
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• 제10권2호통권23호
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• pp.67-71
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• 2007

Objectives : This experimental study was performed to investigate the continuous anti-bacterial potency of Tangpo-san on cultivation of Staphylococcus species(S. aureus, S. epidermidis)that induce eye disease. Methods : Minimal inhibitory concentration(MIC) was measured by dropping to 50 ${\mu}$l diluted Tangpo-san(100%, 10%, 1%, 0.1%) on S. aureus, S. epidermidis that were cultivated from 2 to 6 days. Anti-bacterial potency was measured by the size of inhibition zone with change of volume(20 ${\mu}$l,30 ${\mu}$l,40 ${\mu}$l,50 ${\mu}$l). Results : 1. Anti-bacterial potency of Tanpo-san on S. aureus was not appeared all samples. Anti-bacterial potency with change of volume was increased in propotion to increase volume, and the Anti-bacterial potency of 2 days was equal to 6 days. Anti-bacterial potency of Tangpo-san on S. aureus was appeared continuous. 2. Anti-bacterial potency of Tangpo-san on S. epidermidis was appeared in 100%, 10% on 2 and 6 days, and the Anti-bacterial potency of 6 days was decreased. In 2 days, Anti-bacterial potency was appeared 40 and 50u1, in 6 days, Anti-bacterial potency was appeared all samples. Anti-bacterial potency with change of volume was increased in propotion to increase volume and increased on 6 days, but bacteria was increased. Anti-bacterial potency of Tangpo-san on S. epidermidis wasn't appeared continuous. Conclusions : Anti-bacterial potency of Tangpo-san on cultivation of S. aureus showed continuous, but on cultivation of S. epidermidis was not showed continuous.