• Journal of fish pathology
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• v.13 no.1
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• pp.45-51
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• 2000

Bacterial diseases with mixed infection have recently occurred at land-based flounder farms in Korea. Thus, single antibacterial is not effective for therapy of mixed bacterial diseases of fish because of their different causative bacteria. The purpose of the present study was to obtain basic data for positive usefulness of a combination of antibacterials used for synergism to mixed bacterial diseases of fish. Snergistic interaction in combination of antibacterials was determined by in vitro antimicrobial activity against selected fish-pathogenic bacteria, Vibrio anguillarum, Edwardsiella tarda, Streptococcus sp., Staphylococcus epidermidis, on the basis of Checkerboard assay using fractional inhibitory concentration (FIC) indices. Synergistic interactions were observed in combinations of (oxytetracycline HCL+lincomycin), (tetracycline HCL+florfenicol), (oxytetracycline HCL+florfenicol) against V. anguillarum, (sodium nifurstyrenate+florfenicol), (tetracycline HCL+florfenicol), (sodium nifurstyrenate+oxolinic acid), (oxytetracycline HCL+florfenicol) against E. tarda, (ciprofloxacine+oleandomycin), (oxytetracycline HCL+oleandomycin), (tetracycline HCL+oleandomycin), (oxytetracycline HCL+lincomycin), (oxytetracycline HCL+spiramycin), (oxytetracycline HCL+erythromycin), (doxycycline HCL+oleandomycin), (tetracycline HCL+spiramycin) against Streptococcus sp., and (ciprofloxacine+erythromycin), (florfenicol+erythromycin), (doxycycline HCL+oleandomycin), (ciprofloxacine+oleandomycin) against S. epidermidis.

• YAKHAK HOEJI
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• v.26 no.3
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• pp.169-174
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• 1982

Several strains of bacteria having resistance to macrolide antibiotics were isolated. EMR-1, one of them, exhibited the induced resistance to macrolide antibiotics and this microorganism was identified as a bacterium belong to Bacillus species. The subinhibitory concentration of erythromycin or oleandomycin induced strong resistance to both erythromycin and oleandomycin themselves and to other macrolide antibiotics such as leucomycin, spiramycin and josamycin. The effective concentration of inducer, erythromycin was $0.0016-0.2\mu$g/ml. The inactivating enzyme of these antibiotics was not produced by EMR-1.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.514-518
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• 1992

The present study has been perromed to investigate the optimal conditions for protoplast formation and regeneration of oleandomycin-producing Streptomyces antibioticus (S. antibioticus) KCTC 1081. Mycelia were grown in YME medium containing 0.2% (w/v) glycine and converted into the protoplast by incubating at 35.deg.C for 60 minutes in protoplast buffer (P buffer) containing 4 mg/ml lysozyme. The reversion of protoplasts to the normal filamentous state was examined by the growth on various synthetic agar media. A high reversion rate was obtained by incubating the protoplasts on a hypertonic agar medium containing 20 mM $Mg^{++}$, 5 mM $Ca^{++}$ and 0.3 M sucrose at 28.deg.C for 5 days. From these experiments, we established the improved regeneration medium and a protocol which supports higher and more consistent levels of regeneration of S. antibioticus protoplasts. The regenerant showed an increased antimicrobial activity compared with that of the initial strain.n.n.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.927-932
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• 2006

S-Adenosylmethionine (SAM) is a ubiquitous biomolecule serving mainly as a methyl donor. Our recent studies revealed that SAM controls antibiotic production in Streptomyces. In this study, the functional mode of SAM was studied in S. coelicolor and S. antibioticus ATCC11891, employing S-adenosylhomocysteine (SAH), a methylation reaction product of SAM. Actinorhodin biosynthesis did not require SAM as a methyl donor, whereas SAH enhanced the actinorhodin biosynthesis up to the level comparable to SAM, and the most effective concentration of SAH was higher than that of SAM. In the case of oleandomycin that requires SAM for its biosynthesis, both SAM and SAH at the concentration as low as 100 mM showed comparable efficacy in enhancing the production; SAM at 1 mM concentration additionally stimulated to give a 5-fold enhancement of oleandomycin production. In vitro autophosphorylation of protein kinase AfsK was found to be activated by both SAM and SAH, as well as other structurally related compounds. Our studies demonstrate that SAM regulates antibiotic biosynthesis in a mode independent of its role as a methyl donor and suggest that SAM acts directly as an intracellular signaling molecule for Streptomyces.

• Korean Journal of Poultry Science
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• v.7 no.1
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• pp.53-64
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• 1980

A total of 1503 specimens were submitted to the Poultry Disease Diagnostic Service Laboratory during the year 1966 and 1978. The most frequently diagnosed diseases in order of prevalence were avian mycoplasmosis, staphylococcosis, colibacillosis, salmonellosis and pullorum disease, the percentages of the conditions being 24.6%, 20.0%, 18.0%, 12.6% and 6.4%, respectively, The drug resistance of pathogenic mirnoorganisms isolated during the year 1978 from chicken with colicabacillosis, staphylococcosis or salmonellosis were investigated by the use of disc diffusion technique, the results being as follow. 1) Drug resistance of 63 strains of Escherichia coli More than 95% of the strains tested were sensitive to colistin and gentamicin. The percentages of strains sensitive to kanamycin, chloramphenicol, ampicillin and nitrofurantoin were 66.7%, 60.3%, 60.3% and 47.6%, respectively. Majority of the strains were highly resistant to streptomycin and tetracyline. All the strains were resisistant to bacitracin lincomycin, oleandomycin, penicillin and erythromycin. All the strains tested were resistant to more than two among 10 drugs in common use such as penicillin, erythromycin, streptomycin, tetracycline, neomycin, chloramphenicol, kanamycin, ampicillin and gentamicin, and 27 different resistance patterns were noted. The most frequent multiple resistance pattern was PC, EM, SM and TC (11.1%). 2) Drug resistance of 48 strains of Salmonella More than 95% of the strains tested were sensitive to colistin, gentamicin ana ampicillin. The percentages of st rains sensitive to kanamycin, tetracycline, neomycin and nitrofurantoin were 81,3%, 79%, 72.9%, and 68.0% respectively. None of them was sensitive to streptomycin, oleandomycin, erythromycin, lincomycin and bacitracin. All the strains were resistant to more than one among 7 drugs in common use such as streptomycin, erythromycin, neomycin, tetracycline, kanamycin, ampicillin and gentamicin. The most frequent resistance pattern was SM and EM(66.7%). 3) Drug resistance of 54 strains of Staphylococci All the strains tested were sensitive to gentmaicin, kanamycin and cephalothin. Majority of them were highly sensitive to bacitracin, methicillin, nitrofurantoin and chloramphenicol. The Percentages of strains sensitive to streptomycin, ampicillin, lincomycin and tetracycline were 66.7%, 55.6%, 44.4% and 27.8%, respectively. Among them, 51 strains were resistant to more than one among 11 drugs in common use such as tetracycline, lincomycin, ampicillin, penicillin, streptomycin, erythromycin, neomycin, oleandomycin, chloramphenicol, methicillin and bacitracin, and thirty one different resistance patterns were noted.

• The Journal of the Korean Society for Microbiology
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• v.7 no.1
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• pp.1-8
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• 1972

The authors made a study on the bacteriological identification about unidentified strains which were roughly screened by local health center, which an epidemic diarrhea was outbreak at Ham Yang Gun, Kyeongsang-Namdo in July 1971. And the authors made an attempt to bacteriological Identification, serotyping with slide agglutination, and determination of the susceptibility of identified strains to various chemotherapeutic agents. The results Were obtained as follows: 1. The isolated strains identified Shigella flexneri type 2b(2 strains) and Salmonella paratyphi B(4 strains). 2. Sensitivity test using with three concentrations chemotherapeutic agents(Paper disk used; Eiken chemical Co., Tokyo, Japan): (1) Shigella flexneri type 2b isolated strains were sensitive to kanamycin, colistin(100%) and penicllin(50%) respectively, but resistant to erythromycin, oleandomycin, leucomycin, chloramphenicol, tetracycline, dihydrostreptomycin and sulfadimethoxin(100%) respectively. (2) Salmonella paratyphi B isolated strains were sensitive to chloramphenicol, tetracycline, dihydrostreptomycin, kanamycin, sulfadimethoxine(100%) and colistin(50%) respectively, but resistant to penicillin, erythromycin, oleandomycin and leucomycin(100%) respectively. 3. Sensitivity test using with multodisk urinary code(Paper disk used; Oxoid, London): (1) Shigella flexneri type 2b isolated strains were sensitive to Bactrim, ampicillin, nitrofurantoin, nalidixic add and gentamicin(100%) respectively, but resistant to chloramhpenicol, tetracycline, sulfadiazine and Fanasil(100%) respectively. (2) Salmonell paratyphi B isolated strains were sensitive to Bactrim, chloramphenicol, ampicillin, nitrofurantoin, tetracycline, nalidixic acid, gentamicin(100%) and sulfadiazine(50%) respectively, but resistant to Fanasil(100%) and sulfadiazine(50%) respectively.

• Korean Journal of Veterinary Research
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• v.23 no.2
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• pp.205-209
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• 1983

Some investigations on chronic mastitis in dairy cattle in Kyungnam Province during the year 1982 were conducted with the special reference to the causative agents and their drug resistance. Milk samples from 46 isolated cases of chronic mastitis cattle were investigated bacteriologically and the organisms recovered were examined for their drug susceptibility against the major antibiotics used in this country by the use of disk diffusion susceptibility test. Four major causative agents involved in chronic mastitis were in order of prevalence Staphylococcus aureus (32.6%), Escherichia coli (28.3%), Streptococcus agalactiae (8.7%) and Candida albicans (8.7%). Staph. epidermidis, Streptococcus uberis, Klebsiella pneumoniae and Candida subtropicalis were found to be one of the minor agents. The majority of staphylococcal isolates were highly resistant to the most of antibiotics employed while 8% of them were resistant to gentamicin and 32% to chloramphenicol. The percentages of staphylococcal cultures resistant to penicillin, lincomycin. streptomycin, methicillin, oleandomycin, tetracycline, cephalothin, ampicillin and erythromycin were 100%, 96%, 96%, 92%, 84%, 84%, 80%, 76%, and 64% respectively. Streptococcal isolates were also highly resistant to the majority of the drugs used although 85.7% of them were susceptible to gentamicin. All Escherichia coli isolates were found to be resistant to erythromycin, lincomycin and penicillin while the majority of them were resistant to ampicillin (92.9%), carbenicillin (85.7%), oleandomycin (85.7%), streptomycin(85.7%), kanamycin (78.6%), methicillin (78.6%) and tetracycline (71.4%). The percentages of E. coli cultures resistant to gentamicin, nitrofurantoin, cephalothin and chloramphenicol were 21.4%, 21.4%, 35.7% and 50.0% respectively.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.176-180
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• 1989

Four bacterial strains having inducible resistance to erythromycin were isolated from soil samples in Korea and characterized. MLS inducibility was checked in each strain. Cloning of inducible resistance gene(s) has been tried. Four isolates were identified as B. anthracis, Micrococcus luteus, Streptococcus faecium and B. licheniformis, in which erythromycin, oleandomycin, cirramycin and carbomycin acted as resistance inducers respectively. The resistance gene cloned from B, licheniformis 597 strain using pBS 42 vector was found to have a 3.2 kb insert.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.51-57
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• 1978

Antibiotics susceptibilities of Staphylococci were tested to get useful data for prevention food contamination and treatment of food poisoning. Tested were colony counts, isolation of Staphylococci, identification for the Staphylococcus aureus and resistant patterns to antimcrobial agents. The colonies and Staphylococci isolated from the atmosphere of 37 home kitchens in the morning (07:00-08:00) on Nov. 19, 1977 in Busan. The findings are as follows: 1. The average of colony counts was shown to be 9.6 ranging from 47 to 1 at mean temperature of 18$\circ$C (the highest 21$\circ$C, the lowest 15$\circ$C) 2. Out of total 37 kitchens, 18 Staphylococci were isolated from 15 kitchens with 40.5 per cent, and 4 Staphylococcus aureus were identified with 22.2 per cent from 18 Staphylococci. 3. Isolated Staphylococci were resistant to penicillin(100%), dihydrostreptomycin(93.3%), tetracycline (93.3%) and oleandomycin(66.6%), while the strains were sensitive to sulfonamide(88.6%) and colistin(83.3%). 4. Staphylococcus aureus identified were resistant to dihydrostreptomycin, penicillin and tetracycline, while the strains were sensitive to sulfonamide and colistin.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.551-554
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• 1998

Bacterial specs isolated from common scab lesion on potato (Solanum tuberosum L. c.. Dejima) tuber was identified as Streptomyces turgidiscabies. This organism had flexuous spore chains and grey spore mass color, produced melanin pigment on ISP 7, but did not produce on ISP 6. S. turgidiscabies grew on agar media at pH 4.5, used L-arabinose, D-fructose, D-glucose, D-mannitol, raffinose, rhamnose, sucrose, D-xylose and meso-inositol as carbon sources, and was susceptible to 7% NaCl, thallium acetate (10 $\mu\textrm{g}$/ml, 100$\mu\textrm{g}$/ml), crystal violet (0.5 $\mu\textrm{g}$/ml), phenol (0.1%, wt/vol), oleandomycin (100 $\mu\textrm{g}$/ml), and streptomycin (20 $\mu\textrm{g}$/ml).