• Journal of Microbiology
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• v.35 no.2
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• pp.103-108
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• 1997

To improve the detection of methicillin resistant staphylococci, lowered incubation temperature (30.deg.) and inclusion of sodium chloride in media have been empirically recommended. However, in this study, we found that sodium chloride in Peptone-Yeast Extract-K$\_$2/HPO$\_$4/ (PYK) medium decreased methicillin minimum inhibitory concentrations. Divalent cations were shown to restore the expression of staphylococcal methicillin resistance. However, when it was determined by efficiency of plating, sodium chloride increased methicillin resistance expression on agar medium in which higher divalent cations were contained in the agar medium. The decrease of minimum inhibitory concentrations at 30.deg.C by sodium chloride occurred in Brain Heart Infusion but did not occur in other media investigated. Interestingly, both PYK and Brain Heart Infusion media had peptone, which contain cholic acids having detergent activities. Inclusion of sodium chloride in PYK caused a higher rate of autolysis. Penicillin binding protein 2a that has a low affinity to beta-lactam antibiotics, was highly inducible in methicillin resistant Staphylococcus epidermidis strains. In this study, we found that autolysins that are activated by the sodium chloride decreased the minimum inhibitory concentration at 30.deg.C, and peptidoglycan is weakened due to the presence of methicillin. Peptone in the media may aggravate the fragile cells. However, stabilization due to the presence of divalent cations and production of penicilin binding protein 2a increase the survival of staphylococci.

• Biomedical Science Letters
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• v.20 no.1
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• pp.25-31
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• 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.

• Pediatric Infection and Vaccine
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• v.16 no.2
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• pp.205-209
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• 2009

Staphylococcal toxic shock syndrome (TSS) is a severe systemic illness caused by toxins produced by Staphylococcus aureus. We report a case of staphylococcal TSS in a 16 month-old boy who presented with high fever, vomiting, skin rash, and shock after a burn injury. He was managed with intravenous vancomycin, fresh frozen plasma, and intravenous immunoglobulin. Methicillin-resistant S. aureus (MRSA) was isolated from the burn wound site and anterior nostril of the patient. In addition, the MRSA isolate was genetically characterized.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.621-625
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• 2007

Staphylococcus aureus in Korean kimbab rolls was monitored seasonally in 4 major cities of Korea to investigate the risk of S. aureus in a pre-prepared meal. Thirty-five (28.6%) of 105 kimbab rolls purchased in winter were contaminated with S. aureus with an average level of 2.6 log CFU/g. Thirty-six (33.0%) of 109 kimbab rolls purchased in summer and autumn were contained S. aureus with an average level of 2.9 log CFU/g. Kimbab purchased in snack bars showed higher S. aureus contamination rates with the maximum level of 4.7 log CFU/g than that purchased in convenience stores. Of the raw materials in kimbab, uncooked perilla leaf had the highest contamination rate of S. aureus. Less than 50% of S. aureus isolated from kimbab produced enterotoxin and most of the staphylococcal enterotoxin produced by S. aureus in kimbab was type A.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.894-901
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• 2012

Based on their respective antitumor and thrombolytic activities, the superantigen staphylococcal enterotoxin C2 (SEC2) and staphylokinase (Sak) were chosen for the construction of the novel chimeric proteins Sak-linker-SEC2 and SEC2-linker-Sak using a linker composed of nine Ala residues. Both chimeric proteins possessed nearly the same PBMC proliferation stimulating activity and antitumor activity as SEC2 and thrombolytic activity as Sak. Neither the SEC2 or Sak component of each chimeric protein affected the activity of the other component. The results presented in this study provide a possible strategy to prevent and cure tumor thrombus.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1315-1321
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• 2018

Bacteriocin is ribosomally synthesized by bacteria and inhibits closely related species. In this study we aimed at isolating lactic acid bacteria producing bacteriocin presenting anti-staphylococcal activity. A Lactococcus lactis strain was isolated from kimchi for the purpose and identified by 16S rRNA gene sequencing. As preliminary tests, optimal culture conditions, stabilities against heat, solvents, and enzymes treatments, and type of action (bacteriostatic or bactericidal) of the bacteriocin were investigated. The optimal culture conditions for production of the bacteriocin were MRS broth medium and $25^{\circ}C$ and $30^{\circ}C$ culture temperatures. The bacteriocin was acidic and the activity was abolished by a protease treatment. Its stability was maintained at $100^{\circ}C$ for 15 min and under treatments of various organic solvents such as methanol, ethanol, acetone, acetonitrile, and chloroform. Finally, the bacteriocin showed bactericidal action against Staphylococcus aureus where 200 AU/mL of the bacteriocin decreased the viable cell count (CFU/mL) of S. aureus by 2.5 log scale, compared with a control (no bacteriocin added) after 4-h incubation.

• Pediatric Infection and Vaccine
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• v.11 no.2
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• pp.183-191
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• 2004

Purpose : The purpose of this study was to compare the clinical features of staphylococcal scalded skin syndrome(SSSS) isolated methicillin-resistant Staphylococcal aureus(MRSA) with those of SSSS isolated methicillin-sensitive Staphylococcal aureus(MSSA) in children. Methods : We retrospectively reviewed the medical records and microbiological results of 36 cases of SSSS who were admitted to the Pediatric Department of Ulsan Dong-Kang General Hospital from Jan. 1999 to Dec. 2003. Results : Among 36 cases, there were 7 generalized types, 1 abortive type in MRSA group and 5 generalized types, 6 abortive types in MSSA group. The peak incidence of age was between 2 and 5 years in both groups. SSSS were diagnosed with increasing frequency. Most of MRSA group were diagnosed in 2003(6/8). The peak seasonal incidence was fall and winter in both groups. Facial lesion was observed in all cases followed by flexural lesion in both groups. Staphylococci were isolated from the skin and throat most frequently in both groups. Upper respiratory illness and conjunctivitis were most common preceding infections in both groups. Among 8 cases of MRSA group, 4 cases were treated completely with ampicillin-sulbactam. There was no significant difference of mean duration of admission between MRSA group and MSSA group. Conclusion : There was no significant difference of clinical features between MRSA group and MSSA group although generalized types of SSSS were more common in MRSA group than in MSSA group.

• Clinical and Experimental Pediatrics
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• v.53 no.1
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• pp.48-55
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• 2010

Purpose : Staphylococcal scalded skin syndrome (SSSS) is a relatively uncommon superficial blistering skin disease that is due to Staphylococcus aureus. We had experienced a regional outbreak of SSSS over 3 years in healthy children. Methods : We retrospectively reviewed the medical records of those patients diagnosed as SSSS. Most of neonatal cases were nosocomial infections and excluded from the analysis. The clinical features, laboratory findings, the isolation and antibiotic resistance of S. aureus, the antibiotic management and other supportive treatments were analyzed. Results : Fifty-five patients with SSSS were admitted to our hospital from October 2001 to September 2004. The median age of patients was 3.0 years. Of the 55 patients, 9 were the generalized type, 13 were the intermediate type and 33 were the scarletiniform rash. All the patients were living in neighborhood of the Jinju area. S. aureus were isolated from 9 of the patients and all of the isolated S. aureus were methicillin resistant. All the patients except two were treated with intravenous flocloxacillin or nafcillin and/or cefotaxime. All the patients recovered during the follow-up period of 2 to 3 weeks. Conclusion : We experienced a regional outbreak of SSSS in previous healthy children. Further study for finding the carriers of S. aureus caused SSSS and preventing the spread of this disease is needed. Additionally, guidelines for treating SSSS due to methicillin resistant S. aureus should be established.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.321-327
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• 2005

Staphylococcus aureus is spread worldwide and can result in food poisoning outbreaks. Among samples collected from soil, water, protected houses, packing houses, employees, strawberries, and leaves, and analyzed for S. aureus contamination, 16% samples 'showed S. aureus contamination, particularly on employees' hands, scissors, and strawberries. Examination of enterotoxins A, B, and C genes of S. aureus by PCR revealed sea and seb in 92 and 38% of total strains, respectively, whereas sec was not detected. In conclusion, implementation of Good Agricultural Practice is necessary for preventing food-borne diseases of staphylococcal origin, thereby ensuring the safety of farm-to-table products.

• The Journal of the Korean Society for Microbiology
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• v.35 no.5_6
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• pp.330-332
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• 2000