• 대한의생명과학회지
• /
• 제7권2호
• /
• pp.85-89
• /
• 2001

Many Staphylococcus aureus strains produce enterotoxins causing food poisoning. Staphylococcal enterotoxins are classified by serological criteria into five major groups - subtype A to E. It is difficult, time-consuming, and expensive to detect staphylococcal enterotoxins in the clinical laboratory. In this study, we fried to detect the enterotoxin genes of Staphylococcus aureus strains isolated from clinical specimens and Kimbap - rice rolled in a sheet of laver - using multiplex PCR technique. A total of 77 strains of Staphylococcus aureus from clinical specimens and 78 strains from Kimbap were isolated. Among clinical isolates of S. aureus, 60 strains (78.0%) were identified as producing enterotoxins. A total offs strains (91.6%) in the 60 staphylococcal enterotoxin producing strains were enterotoxin subtype C. In case of kimbap: 43 (55.1%) strains were detected to produce enterotoxins and 39 (90.6%) enterotoxin producing strains were subtype A.

• 대한수의학회지
• /
• 제38권3호
• /
• pp.553-558
• /
• 1998

Using the previous established multiplex PCR (mPCR), the presence of six kinds of staphylococcal superantigen (SAg) genes was investigated for nineteen Staphylococcus aureus isolates from the commercialized meat sources. As a result, only one isolate from pork among 19 S aureus isolates (5.3%) was confirmed as a potential SAg producer and harbored sec gene. The results in this study suggest that meat may not be major contagion of staphylococcal food poisoning (SFP) in Korea and that staphylococcal enterotoxin type C may be associated with the disease. Also, the mPCR method in this study can be a useful genotypic method which can overcome the typical disadvantages of conventional antibody-based methods due to antigenic homology, and furthur survey on food-borne S aureus isolates can provide the important epidemiological data for SFP in Korea.

• 대한의생명과학회지
• /
• 제20권1호
• /
• pp.25-31
• /
• 2014

Atopic dermatitis (AD) is an inflammatory, relapsing, chronic skin disease and lesions in AD are frequently colonized with Staphylococcus aureus (S. aureus). Activation of T cells and IgE production by staphylococcal enterotoxins B (SEB) plays a crucial role in the pathogenesis of AD. Enterococcus faecalis (E. faecalis) is a nonpathogenic bacterium and produces the probiotic products that have been shown to have inhibitory effects on inflammatory responses. In present study, we carried out to assess the anti-inflammatory role of lyzed E. faecalis against the damaging effects of SEB on AD related immune responses. Furthermore, we attempted to determine whether the co-cultured lyzed E. faecalis can influence the colonization of S. aureus. As a result, we identified the effect of E. faecalis lysate as a potent therapeutic agent for atopic dermatitis (AD). E. faecalis lysate reduces the productions of total IgE and cytokines of AD-related immune cells in response to SEB stimulation. The proliferation of S. aureus was also inhibited by E. faecalis lysate. In conclusions, E. faecalis lysate may improve the skin-defense system disturbed by atopic condition, and may prevent subsequent secondary infection of S. aureus and development of AD.

• Animal Bioscience
• /
• 제34권4호
• /
• pp.734-742
• /
• 2021

Objective: The present study aimed to investigate the occurrence and species of coagulase-positive staphylococci (CoPS) and coagulase-negative staphylococci (CoNS) in retail pork meat samples collected during nationwide monitoring. The staphylococcal isolates were characterized for antimicrobial and zinc chloride resistance and enterotoxigenic potential. Methods: A total of 260 pre-packaged pork meat samples were collected from 35 retail markets in 8 provinces in Korea for isolation of staphylococci. Antimicrobial and zinc chloride resistance phenotypes, and genes associated with the resistance phenotypes were determined on the isolates. Furthermore, the presence and distribution of 19 staphylococcal enterotoxin (SE) genes and enterotoxin-like genes among the pork-associated staphylococci were determined by multiplex polymerase chain reaction-based assays using the specific primer sets. Results: A total of 29 staphylococcal strains (29/260, 11.1%) were isolated from samples of retail pork meat, 24 (83%) of which were CoNS. The four CoNS species identified were S. saprophyticus (n = 16, 55%), S. sciuri (n = 3, 10%), S. warneri (n = 3, 10%), and S. epidermidis (n = 2, 7%). Among the 29 isolates, four methicillin-resistant CoNS (MR-CoNS; three S. sciuri and one S. epidermidis) and one methicillin-resistant CoPS (MR-CoPS; one S. aureus) were identified. In addition, a relatively high level of tetracycline (TET) resistance (52%) was confirmed in CoNS, along with a predominant distribution of tet(K). The most prevalent SEs were sep (45%), and sen (28%), which were carried by 81% of S. saprophyticus. Conclusion: These findings suggest that CoNS, especially S. saprophyticus strains, in raw pork meat could be a potential risk factor for staphylococcal food poisoning (SFP), and therefore, requires further investigation to elucidate the role of SEls in SFP and virulence of the pathogen. Our results also suggest that CoNS from raw pork meat may act as a source for transmission of antimicrobial resistance genes such as staphylococcal cassette chromosome mec and tet(K).

• 대한수의학회지
• /
• 제39권4호
• /
• pp.806-810
• /
• 1999

A multiplex-polymerase chain reaction (PCR) assay was used to detect staphylococcal enterotoxin production by 12 strains of Staphylococcus aureus isolated from clinical specimens. To evaluate the efficacy and/or sensitivity of this method, the results were compared to those obtained with the reversed passive latex agglutination kit (SET-RPLA, Denka Seiken, Japan). Of 10 strains positive by PCR were positive by RPLA but two strains, representing high sensitivity of the former method. Enterotoxin B was the most prevalent by the two methods. The kappa index between the two methods was 0.826, indicating a higher agreement and fully reliable for use. These results would suggest that sensitive, inexpensive, and relatively rapid multiplex-PCR technique may be an effective means for the detection of staphylococcal enterotoxin genes as an alternative to traditional methods such as kits or immunological methods, which depend upon the amount of enterotoxin produced.

• 대한의생명과학회지
• /
• 제20권2호
• /
• pp.96-102
• /
• 2014

Staphylococcal enterotoxin B (SEB) is bacterial toxin that induces the activation of immune cells. Because the inhibition of pro-inflammatory effect of SEB can resolve the inflammation, I determined the influence of functional or structural change of SEB on immune cells. The post translational modification of protein occurs through carbamylation. Carbamylation can change the structure of proteins and can modify the biological activity of protein. In the present study, I investigated the effect of carbamylated SEB (CSEB) on the inflammatory response mediated by LPS in HL-60 cells. To determine the anti-inflammatory effect of CSEB, I produced carbamylated SEB using potassium cyanate (KCN) and then examined whether CSEB involved in cytokine releases and apoptosis of LPS-stimulated HL-60 cells. Although CSEB had not any effect on the LPS-stimulated HL-60 cells, the protein levels of IL-8, TNF-${\alpha}$ and IL-$1{\beta}$ were significantly decreased by CSEB without cytotoxicity. CSEB also blocked Akt and NF-${\kappa}B$ activation. These results indicate that the suppressive effect of CSEB in LPS-stimulated cytokine releases is occurred by inhibition of Akt and NF-${\kappa}B$ activity. Through further studies, CSEB may be used as anti-inflammatory molecule that makes the immune system more efficient.

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

• 한국식품위생안전성학회지
• /
• 제16권3호
• /
• pp.159-167
• /
• 2001

집단식중독 환자에서 분리한 Staphylococcus aureus에 대한 항생제 감수성, enterotoxin 형별을 PCR로 조사한 결과는 다음과 같았다. 1. 의심환자분변 413건중 105건(25.4%)에서 Staphylococcus aureus coagulase 양성 균주가 분리되었다. 2. enterotoxin 생산성을 PCR로 조사한 결과 총 45주(42.9%)에서 enterotoxin gene이 확인되었으며, 이 중 H형 단독생산주가 29주(64.4%)로 가장 많았으며. A형 단독생산주 5주(11.1%), A형 및 H형 혼합생산주 4주(8.9%), G형 생산주 2주(4.4%)및 I형 생산주 1주(2.2%)이었다. 3. 시험한 105주 중 48주(45.7%)에서 항생제 내성이 확인되었으며, 이 중 penicillin에 대한 내성이 38.1%로 가장 높았으며, ampicillin과 penicillin은 중등도 내성이 각각 42.9%, 61.0%이었다. chloramphenicol, clindamycin, methicillin. trimethoprim, vancomycin은 모두 감수성이었다. 또한 단제 내성이 85.4%를 차지하였으며, 2제 내성이 12.5%, 3제내성이 2.1%이었다.

• 한국식품위생안전성학회지
• /
• 제34권6호
• /
• pp.576-582
• /
• 2019

Staphylococcus pseudintermedius는 개에서 기회감염을 유발하는 병원체이며, 공중보건학적으로도 주요한 인수공통 병원체이다. 개에서 분리된 S. pseudintermedius 균주들은 주로 항생제 내성 및 개에서 피부 감염을 유발하는 주요 원인균으로 연구되어 왔지만, 가축에서 분리된 S. pseudintermedius 균주들의 항생제 내성 및 장내 독소 생성에 대한 정보는 매우 제한적이다. 본 연구에서는 개, 돼지, 육우에서 분리된 S. pseudintermedius 균주들에서 18가지의 장내 독소 (staphylococcal enterotoxin; SE) 유전자와 toxic shock syndrome toxin 유전자(tst-1)의 분포양상을 조사하였다. 또한, S. pseudintermedius 균주들의 항생제 내성 양상과 더불어 mecA 유전자 및 SCCmec type 또한 확인하였다. 육우에서 분리한 하나의 균주를 제외한 모든 개와 돼지 분리주 들이 4개 이상의 항생제에 내성을 보였으며, 개에서 분리된 6개의 균주 중 4개의 S. pseudintermedius 균주들이 메티실린 내성과 더불어 SCCmec V를 가진 것으로 확인 되었다. 총 11개의 SE 유전자들 (seb, sec, see, seg, sei, sej, sel, seo, sep, seq, seu) 및 tst-1가 개, 돼지 및 육우로부터 분리된 S. pseudintermedius 균주들에서 확인 되었으며, 대부분의 분리주들 (83%)에서 2개 이상의 SE 유전자들이 확인 되었고, 그 중 sel (42%) 및 sep (42%)가 가장 빈번하게 검출 되었다. 본 연구를 통하여 반려견에서 뿐만 아니라 주요 가축에서 존재하는 S. pseudintermedius 균주들에서 높은 항생제 내성 양상을 확인 하였으며, 항생제 내성과 더불어 여러 staphylococcal enterotoxin 및 tst-1 유전자들을 전파할 가능성을 확인 하였다.

• Journal of Veterinary Science
• /
• 제24권6호
• /
• pp.85.1-85.13
• /
• 2023

Background: A recent increase in the occurrence of canine skin and soft tissue infections, including otitis externa and pyoderma, caused by antimicrobial-resistant Staphylococcus pseudintermedius and S. schleiferi has become a significant public and veterinary health issues. Objective: We investigated the virulence potentials associated with the occurrence of canine otitis externa in S. pseudintermedius and S. schleiferi. Methods: In this study, the prevalence of genes encoding leukocidins, exfoliative toxins, and staphylococcal enterotoxins (SEs) was investigated using previously characterized S. pseudintermedius (n = 26) and S. schleiferi (n = 19) isolates derived from canine otitis externa. Susceptibility to cathelicidins (K9CATH and PMAP-36) and hydrogen peroxide (H₂O₂) was also examined in both staphylococcal species. Results: A high prevalence of genes encoding leukocidins (lukS/F-I, lukS1/F1-S, and lukS2/F2-S), exfoliative toxins (siet, expB, and sset), and SEs was identified in both S. pseudintermedius and S. schleiferi isolates. Notably, S. pseudintermedius isolates possessed higher number of SE genes, especially newer SE genes, than S. schleiferi isolates harboring egc clusters. Although no significant differences in susceptibility to K9CATH and H₂O₂ were observed between the two isolate groups, S. pseudintermedius isolates exhibited enhanced resistance to PMAP-36 compared to S. schleiferi isolates. Conclusions: These findings suggest that high a prevalence of various toxin genes together with enhanced resistance to cathelicidins may contribute to the pathogenicity of S. pseudintermedius and S. schleiferi in canine cutaneous infections.