• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.193-197
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• 1989

The three new Alkylene bisdithionreido $\beta$-lactam derivatives were synthesized and evaluated for antimicrobial activities. Treatment of cefadroxil.2DMF with alkylene diisothiocyanate which was obtained by the reaction of alkylene diamine with carbon disulfide, sodium hydroxide and ethyl chloroformate afforden alkylene bisdithioureido $\beta$ -lactam derivatiives. The antimicrobial activities of the compounds synthesized were ethylene bisdithioureido $\beta$-lactam derivative lost the sensitivity against Escherichia coli but showed potent antimicrobial activity against $\beta$-lactams Escherichia coli, but, tetramethylene bisdithioureido $\beta$-lactam derivative and hexamethylene bisdithioureido $\beta$ -lactam derivative compounds showed diminished or no antimicrobial activities.

• YAKHAK HOEJI
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• v.39 no.2
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• pp.131-136
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• 1995

Clinically isolated bacterial strains resistant to almost of all the clinically superior .betha.-lactam antibiotics can be used to screen the promising ones among the newly synthesized $\beta$-lactam antibiotics. To select the resistant strains, the susceptibility of 389 strains of S. aureus, 144 strains of coagulase negative staphylococci, 509 strains of E. coli, 115 strains of E. cloacae and 187 strains of P. aeruginosa to methicillin, ampicillin, piperacillin and gentamicin was determined. The susceptibility of 19 bacterial strains selected through the first screening to cefixime, cefotiam, cefotaxime, flomoxef, cepfirome, cefdnir, SCE-2787, panipenem and imipenem was determined. Four strains of S. aureus finally selected have high degree of resistance to almost of all $\beta$-lactam antibiotics used and also produce $\beta$-lactamases. These 4 strains of S. aurues can be used to screen effectively the promising $\beta$-lactam antibiotics among the numerous numbers of the newly synthesized $\beta$-lactam antibiotics.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.113-120
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• 2003

The antimicrobial effect of ${\beta}$-lactam antibiotics, which had ${\beta}$-lactamase inhibitor activity, on Staphylococcus aureus isolated from mastitis was investigated in this study. Out of 166 isolates, 99 isolates (59.6%) produced ${\beta}$-lactamase, and 98 isolates of 99 were ${\beta}$-lactamase positive in above $12.5{\mu}g/m{\ell}$ MIC of penicillin. In the providence distribution, ${\beta}$-lactamase production rate of 4 providence, Gangwon, Gyeonggi, Chungcheong, and Jeolla was 100%, 65.7%, 58.8%, and 50.0%, respectively. Antibiotic activities of ${\beta}$-lactam antibiotics against lactamase positive isolates also were investigated. Antimicrobial effects of ampicillin/sulbactam or amoxicillin/clavulanic acid treated group were better than ampicillin or amoxicillin treated group. In antimicrobial effects on intracellular S aureus, there was no difference 1 hour and 4 hour treatment in control, ampicillin, and amoxicillin group, but in 18 hours treatment, ampicillin/sulbactam or amoxicillin/clavulanic acid had a better effect than ampicillin or amoxicillin (p<0.05).

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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• pp.33-33
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• 2003

There prevalence of $\beta$-lactamases bacteria in animals has been increased since 1990s [1]. The resistance in E coli which is mediated by $\beta$-lactamases hydrolyze the $\beta$-lactam ring eventually inactivate the antibiotics [2]. Generally, $\beta$-lactamases can be classified into four main groups and eight subgroups according to their functional and structural characteristics [3]. The detection of $\beta$-lactam antibiotic-resistant bacteria by DNA chip has been described [4]. The chip has a specific probe DNAs that contained the $\beta$-lactam antibiotic-resistant genes which was labeled by multiplex PCR reaction with a mixture of primer sets that were designed to amplify specific gene. Here we report the susceptibility of enteropathogenic E. coli isolated from pigs in Korea using the DNA chip in detecting $\beta$-lactam antibiotic-resistant genes. (omitted)

• Fisheries and Aquatic Sciences
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• v.19 no.10
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• pp.45.1-45.5
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• 2016

As a novel strategy to remove ${\beta}$-lactam antibiotic residues from fish tissues, utilization of ${\beta}$-lactamase, enzyme that normally degrades ${\beta}$-lactam structure-containing drugs, was explored. The enzyme (TEM-52) selectively degraded ${\beta}$-lactam antibiotics but was completely inactive against tetracycline-, quinolone-, macrolide-, or aminoglycoside-structured antibacterials. After simultaneous administration of the enzyme with cefazolin (a ${\beta}$-lactam antibiotic) to the carp, significantly lowered tissue cefazolin levels were observed. It was confirmed that the enzyme successfully reached the general circulation after intraperitoneal administration, as the carp serum obtained after enzyme injection could also degrade cefazolin ex vivo. These results suggest that antibiotics-degrading enzymes can be good candidates for antibiotic residue depuration.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.398-401
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• 1988

Streptomyces sp. producing $\beta$-lactamase inhibitor were isolated from soil. The culture conditions for the production of the $\beta$-lactamase inhibitor were evaluated and isolation produce of the $\beta$-lactamase inhibitor from the culture broth was also established. Some characters of the partially purified $\beta$-lactamase were determined.

• Korean Journal of Microbiology
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• v.43 no.2
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• pp.116-123
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• 2007

The purpose of this study was typing the plasmid mediated extended spectrum ${\beta}-lactamases$ produced by enteric bacteria isolated from rivers in Pusan. Six strains of Eschericha coli and fifteen strains of Klebsiella pneumoniae transferred their plasmid mediated extended spectrum ${\beta}-lactamase$ genes to the recipient strain Eschericha coli J53 $Azid^{R}$. The plasmid mediated extended spectrum ${\beta}-lactamase$ genes were sequenced directly after PCR and the types were determined by the BCM Search Launcher and GenBank nucleotid database. Determined types of the plasmid mediated extended spectrum ${\beta}-lactamases$ were TEM-52 and SHV-12. TEM-52 was isolated from both Escherichia coli and Klebsiella pneumoniae. However SHV-12 was isolated from Klebsiella pneumoniae only. The results indicated that the plasmid mediated extended spectrum ${\beta}-lactamase$ producing bacteria spreded over the area of clinical to the nature in Korea.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.25-27
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• 1984

Some $\betha$-lactam antibiotics-penicillins and cephalosporins-were determined by gas chromatography (GC) with flame photometric detector (FPD) which was selective and sensitive to sulfur-containing compounds. Methyl ester derivatives of carboxyl group in $\betha$-lactam antibiotics were prepared using 0.5Mmethyl iodide in methylene chloride and were taken for gas chromatography with 0.9% or 0.6% QF-1 on Chromosorb WAW-DMCS. We have found that it is possible to determine methyl esters of $\betha$-lactam antibiotics by GC/FPD.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.185-190
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• 1989

Geometries for a number of representative ${\beta}$ -lactam antibiotics (penams, cephems and monobactams) have been calculated by computer graphics/molecular mechanics energy minimization procedures using both MM2 and AMBER force fields. The calculated geometries have been found in reasonable agreement with the geometries reported in the X-ray crystal structures, especially in terms of the pyramidal character of the amide nitrogen in the ${\beta}$-lactam ring and the Cohen distance. Based on these calculations, it is suggested that the nitrogen atom in the monobactams may also have pyramidal geometries in the biologically active conformations.

• Korean Journal of Veterinary Service
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• v.30 no.4
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• pp.505-510
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• 2007

This study was conducted to detect ${\beta}$-lactam antibiotic-resistant genes in the 400 E coli isolates from porcine fecal samples in Korea by a DNA chip. The DNA chip contains the specific probe DNAs of the ${\beta}$-lactam antibiotic-resistant genes that had been labeled with a mixture of primer set designed to amplify specific genes (PSE, OXA, FOX, MEN, CMY, TEM, SHV, OXY and AmpC) using a multiplex polymerase chain reaction (PCR). Of 400 isolates 339 contained at least one ${\beta}$-lactamases gene. Resistance to ${\beta}$-lactamases was mediated mainly by AmpC (n = 339, 100%), and followed by TEM (n = 200, 59.0%), CMY (n = 101, 29.8%), PSE (n = 30, 8.9%) and both OXA and SHV genes (n = 20, 5.9%), while the FOX, MEN and OXY genes were not detected. The other sixty-one did not contain any ${\beta}$-lactamase genes even though they were resistant to antimicrobial drugs. In conclusion, the DNA chip system can be used as a rapid and reliable method for detecting of ${\beta}$-lactamases genes, which will help veterinarians select the antibiotics for monitoring and treating of animal diseases.