• 한국동물위생학회지
• /
• 제23권1호
• /
• pp.61-69
• /
• 2000

Thirty-one dairy cow from two farm(more than 500,000 cells/ml of bulk milk) in Kyongbuk northern province were selected because of their high somatic cell(more than 500,000 cells/ml of milk In individual cow). Each cow received. staphylococcus aureus vaccine(Labac Staph) and immunostimulant(Ultracon) by intramuscular injection to be repeated every fifteen days for S times. The present study was investigated variation of somatic cell after administration of Labac Staph and Ultracon, and antibiotics resistance of isolated staphylococcus spp from milk in selected cow. The results obtained through the survey were summarized as follows ; 1. Ten dairy cow was injected in A farm. Chronic mastitic two cow after 2rd injection was weeded out the herd. Decrease rate of somatic cell after 1st, 2nd, ,3rd, 4th and 5th administration were 41.4%, 35.6%, 56.4%, 65.4% and 36.7%, respectively. Twenty-one cow was injected in B farm. Chronic mastitic five cow after ,3rd injection was weeded out the herd. Decrease rate of somatic cell after 1st, 2nd, 3rd, 4th and 5th administration were 36.9%, 59.9%, 24.5%, 62.6% and 78.4%, respectively. 2. In A farm, isolated staphylococcus spp were identified as S hyicus 2 strains(11.8%), coagulase negative staphylococcus 15 stains(89.2%) and S epidermidis 6strain(35.3%). In B farm, isolated staphylococcus spp were identified as S aureus 19 strains(55.98%) and coagulase negative staphylococcus 15 strains (44.2%). 3. In A fm, antibiotics resistant rate of isolated staphylococcus spp was high at ampicillin, penicillin and kanamycin, and middle at neomycin, streptomycin and erythromycin. in B farm, antibiotics resistant rate was moderate at ampicillin, penicillin, gentamicin, ka-namycin, neomycin, streptomycin, erythromycin and tetracycline, and coagulase negative staphylococcus spp was moderate at streptomycin.

• 동아시아식생활학회지
• /
• 제5권1호
• /
• pp.101-107
• /
• 1995

Staphylococcus aureus, the most salt-tolerant food-borne pathogen, produces enterotoxins which may cause symptoms such as vomiting, diarrhea, nausea, and cramps. Since this bacterium has been able to grow at extremely high osmolarity its identity in foods with low water activity values such as salted or dried foods is of great concern. In this study, the growth of S. aureus at high osmolarity has been studied and the doubling time of S. aureus grown at TSB medium containing 15% NaCl has been found to be increased to 4∼5 hours. The stimulation of proline uptake after exposure of cells to high concentration of both extracellular KCl and sucrose was not increased. Stimulation of proline uptake at these environment only occured when 25mM NaCl was present I transport buffer. In additional experiments, the time required to reach mid-logarithmic phase in defined medium of high osmolarity found to be reduce by the presence of glycine betaine, proline, and choline.

• 약학회지
• /
• 제35권1호
• /
• pp.22-29
• /
• 1991

pMB4 is a 2.4-kilobase plasmid of Staphylococcus aureus TR-1 that confers inducible resistance to the macrolide-lincosamide-streptogramin B(MLS) antibiotics. By subcloning studies, it was found that the MLS resistance determinant was located at 1.0Kb fragment between Sau3AI and TaqI sites. DNA sequence of the MLS resistant determinant, named ermC-4 was determined, and found to be highly homologous with that of ermC. Because the leader peptide sequence of ermC-4 was identical with that of ermC, the expression of the resistance gene is thought to be controlled by posttranscriptional attenuation in S. aureus TR-1.

• BMB Reports
• /
• 제40권1호
• /
• pp.7-14
• /
• 2007

Helicases are ubiquitous enzymes, which utilize the energy liberated during nucleotide triphosphate hydrolysis to separate double-stranded nucleic acids into single strands. These enzymes are very attractive targets for the development of new antibacterial compounds. The PcrA DNA helicase from Staphylococcus aureus is a good candidate for drug discovery. This enzyme is unique in the genome of S. aureus and essential for this bacterium. Furthermore, it has recently been published that it is possible to identify inhibitors of DNA helicases such as PcrA. In this report, we study the properties of recombinant PcrA from S. aureus purified from Escherichia coli to develop ATPase and helicase assays to screen for inhibitors.

• 한국임상수의학회지
• /
• 제38권5호
• /
• pp.225-230
• /
• 2021

A 4-year-old gelding Thoroughbred racehorse, which had been undergoing antibiotic therapy at a local veterinary clinic, was referred to the KRA veterinary center with a 20-day history of continuous right nasal discharge. Patient's history, endoscopic examination, and radiographic examination revealed primary maxillary sinusitis. Under sedation, surgical intervention was performed to collect samples and remove the accumulated mucopurulent exudate in the sinus. Swab samples were collected from the sinus during surgery for cytology and antimicrobial susceptibility testing. Only one type of bacteria was cultured, and molecular analyses of 16S ribosomal RNA gene sequences identified it as Staphylococcus aureus (S. aureus). The isolate was resistant to multiple antibiotics, which are frequently used in equine practice. Trimethoprim-sulfamethoxazole was chosen based on antibiotic susceptibility test, trephination, and sinus lavage using saline were applied to treat bacterial sinusitis. The clinical signs improved after 1 month and the patient resumed training. This report describes S. aureus isolated from bacterial maxillary sinusitis in a horse and its antibiotic susceptibility.

• International Journal of Oral Biology
• /
• 제46권1호
• /
• pp.45-50
• /
• 2021

This study evaluated the antimicrobial activity of Endoseal TCS, an mineral trioxide aggregate-based root canal sealer, mixed with water-soluble mangostin derivatives (WsMD) of Garcinia mangostana L. (mangosteen) ethanol extract against Enterococcus faecalis and Staphylococcus aureus. The antibacterial activity of Endoseal TCS mixed with WsMD against three strains of E. faecalis and three strains of S. aureus was performed using agar diffusion test. The data showed that Endoseal TCS mixed with 0.115% WsMD had a zone of inhibition of 0.7 ± 0.2-2.4 ± 0.1 mm. The results suggest that Endoseal TCS mixed with WsMD of Garcinia mangostana L. ethanol extract is useful as a root canal sealer with antibacterial activity against E. faecalis and S. aureus.

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

• Journal of Microbiology and Biotechnology
• /
• 제26권2호
• /
• pp.263-269
• /
• 2016

Temperate phages have been suggested to carry virulence factors and other lysogenic conversion genes that play important roles in pathogenicity. In this study, phage TEM123 in wild-type Staphylococcus aureus from food sources was analyzed with respect to its morphology, genome sequence, and antibiotic resistance conversion ability. Phage TEM123 from a mitomycin C-induced lysate of S. aureus was isolated from foods. Morphological analysis under a transmission electron microscope revealed that it belonged to the family Siphoviridae. The genome of phage TEM123 consisted of a double-stranded DNA of 43,786 bp with a G+C content of 34.06%. A bioinformatics analysis of the phage genome identified 43 putative open reading frames (ORFs). ORF1 encoded a protein that was nearly identical to the metallo-β-lactamase enzymes that degrade β-lactam antibiotics. After transduction to S. aureus with phage TEM123, the metallo-β-lactamase gene was confirmed in the transductant by PCR and sequencing analyses. In a β-lactam antibiotic susceptibility test, the transductant was more highly resistant to β-lactam antibiotics than S. aureus S133. Phage TEM123 might play a role in the transfer of β-lactam antibiotic resistance determinants in S. aureus. Therefore, we suggest that the prophage of S. aureus with its exotoxin is a risk factor for food safety in the food chain through lateral gene transfer.

• 한국환경보건학회지
• /
• 제19권1호
• /
• pp.71-76
• /
• 1993

Nasal carrige of Staphylococcus was studied in relation to its significance as a source of the Staphylococci that caused hospital-acquired infection. Due to the trend of the increasing r esistance of S. aureus to many antimicrobial agents, it is necessary to study the sensitivity to antibiotics of this infectious microorganisms. 50 persons from general hospital and 50 college students were the object of this study. The following results were obtained 3 0 Strains of S. aureus were isolated. The rate of S. aureus nasal carrying were 26% in college students and 34% in hospital personnel. S. aureus which showed resistance to penicillin were 90%, tetracyclin 43%, erythromycin 37% and oxacillin 17%. The number of penicillin resistance of S. aureus were 11 (84%) in college students and 16 (94%) in hospital personnel. The number of strains of penicillin resistant S. aureus which produced 13-1actamase were 9 (82%) in college student and 14 (88%) in hospital personnel. Methicillin-resistant S. aureus (MRSA) which showed resistance to erythromycin and penicillin G were 100%, tetracyline, cephalothin and clindamycin were over 40% respectively, gentamicin 20%, SAM 20% and chloramphenicol 0%.

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