A clinical isolate of Salmonella enterica serotype Enteritidis in Korea was found to produce the extended-spectrum beta-lactamase CTX-M-15. The isolate was recovered in 2008 from the stool of a 3-yr-old boy with gastroenteritis. This isolate was found to be resistant to multiple drugs, including ampicillin, piperacillin, cefotaxime, ceftazidime, cefepime, and aztreonam. The resistance to cefotaxime was transferred by conjugation to recipient Escherichia coli J53. The patient was eventually successfully treated with trimethoprim-sulfamethoxazole. This is the first report of the bla (CTX-M-15) gene in S. enterica serotype Enteritidis in Korea.
Child, Preschool ; Gastroenteritis/diagnosis/*microbiology ; Humans ; Male ; Salmonella enteritidis/genetics/*isolation & purification ; Serotyping ; beta-Lactamases/*genetics

Klebsiella pneumoniae ; enzymology ; isolation & purification ; Microbial Sensitivity Tests ; beta-Lactamases ; classification

It is known that penicillinase-producing Neisseria gonorrhoeae (PPNG) are frequently found in South-East Asia and the infection does not respond to the recommended does of penicillin. N. gonorrhoeae cultures isolated during June 1977 to June 1979, from Yonsei Medical Center patients were tested for beta-lactamase production. Among the 127 isolates tested one was positive by the rapid iodometric method. The culture also gave a positive result by the method of Hodge et al. No zone of inhibition was observed when its susceptility was tested with a 10 unit penicillin disk. The patient who yielded the organism was a 51-year-old housewife living in Seoul. Neither she nor her husband had ever traveled abroad. This result documented the presence of PPNG in this community. In the future laboratories may require careful watch to detect further spreading of PPNG.
Female ; Gonorrhea/drug therapy ; Human ; Korea ; Neisseria gonorrhoeae/enzymology* ; Neisseria gonorrhoeae/isolation & purification ; Penicillins/therapeutic use ; beta-Lactamases/isolation & purification*

No abstract available.
Aged ; Female ; Humans ; Klebsiella Infections/*diagnosis/microbiology ; Klebsiella pneumoniae/*enzymology/isolation & purification ; Pneumonia/*diagnosis/microbiology ; Turkey ; beta-Lactamases/*metabolism

Bacterial Infections ; microbiology ; therapy ; Humans ; Integrative Medicine ; Male ; Microbial Sensitivity Tests ; Middle Aged ; beta-Lactamases ; isolation & purification

OBJECTIVETo investigate the possible differences in antimicrobial resistance of Escherichia coli isolated from different samples in children.

METHODSSix hundred and twenty-nine samples from urine, sputum, blood and secretion were collected from June 2004 to May 2009 for bacterial identification by VITEK-32 automatic system and antimicrobial susceptibility tests by Kirby-Bauer method. The drug resistance rate of Escherichia coli isolated from different samples was compared.

RESULTSTwo hundred and sixty strains of Escherichia coli were isolated , and 108 of which were from urine , 64 from sputum, 54 from secretion and 23 from blood. ESBLs were detected in 96 (36.9%) of the 260 isolates, AmpC enzymes in 32 (12.3%), and ESBLs+AmpC in 8 (3.1%). The ESBLs positive rate of Escherichia coli isolates from sputum was significantly higher than that from other samples (P<0.05). The antimicrobial resistance rate of Escherichia coli strains from different samples to amoxicillin/clavulanic acid, ticarcillin/clavulanic acid, piperacillin, cefotaxime, cefuroxime, cefepime, gentamicin, cotrimoxazole, and nitrofurantoin was different. The resistance rate of the strains from sputum samples was higher than that from the other samples (P<0.05).

CONCLUSIONSEscherichia coli isolated from different samples have different antimicrobial resistance rates in children, so the selection of antibiotics for infections confirmed by bacterial cultures from different samples should based on drug sensitivity results.

Adolescent ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; enzymology ; isolation & purification ; Female ; Humans ; Male ; beta-Lactamases ; analysis

Extended-spectrum beta-lactamases (ESBLs) in gram-negative organisms have been implicated as the enzymes responsible for resistance to oxyimino-cephalosporins. The incidence of ESBL- producers in Korean isolates of Escherichia coli and Klebsiella pneumoniae were in the range of 4.8 7.5% and 22.5 22.8%, respectively. The ESBL-producing isolates revealed variable levels of resistance to cefotaxime, ceftazidime and aztreonam. They also showed the elevated MIC values of non-beta-lactam antibiotics. SHV-12 and SHV-2a were the enzymes most frequently found in K. pneumoniae strains, but TEM-52 was the most prevalent in E. coli isolates. About 15% of ESBL-producing isolates of Enterobacteriaceae produced CMY-1 enzyme, which conferred resistance to cephamycins such as cefoxitin as well as oxyimino-cephalosporins. Thus, the most common types of ESBLs in Korea are TEM-52, SHV-12, SHV-2a, and CMY-1.
Drug Resistance, Microbial/physiology ; Enterobacteriaceae/isolation & purification ; Enterobacteriaceae/chemistry* ; Enterobacteriaceae Infections/microbiology ; Human ; Korea ; beta-Lactamases/analysis*

OBJECTIVETo investigate the molecular mechanism of carbapenem resistance in the clinical isolates of Acinetobacter baumannii from Xi'an and their profile of carbapenemase production.

METHODSA total of 146 Acinetobacter baumannii strains were isolated from 6 general hospitals in Xi'an. Antimicrobial susceptibility test was performed for all the strains, followed by detection of imipenem resistance using E-test for metallo-beta-lactamase (MBL) and NaCl inhibition test for OXA type carbapenemase. Bla(OXA-23)and bla(OXA-58) were amplified by PCR, and the positive products were sequenced.

RESULTSFrom the collected strains, 15 non-repetitive imipenem-resistant Acinetobacter baumannii strains were identified, among which 14 yielded negative results in E-test for MBL production. All the resistant strains showed increased sensitivity to imipenem after NaCl inhibition, suggesting the presence of carbapenemase production. Eleven of the strains harbored OXA -23 type gene and 1 harbored OXA -58 type gene. The concordance rate of the results by NaCl inhibition test and PCR was 85.7%.

CONCLUSIONSProduction of OXA-type carbapenemase is the most important reason for carbapenem resistance in Acinetobacter baumannii in Xi'an. The OXA-58 type gene is a novel carbapenemase genotype in China. NaCl inhibition test is a convenient and cost-effective method for detecting carbapenemase in Acinetobacter baumannii.

Acinetobacter baumannii ; drug effects ; genetics ; isolation & purification ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; China ; Humans ; Imipenem ; pharmacology ; beta-Lactam Resistance ; beta-Lactamases ; genetics

In this study, we investigated the molecular characteristics of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae isolates that were recovered from an outbreak in a Korean hospital. A new multilocus sequence typing (MLST) scheme for K. pneumoniae based on five housekeeping genes was developed and was evaluated for 43 ESBL-producing isolates from an outbreak as well as 38 surveillance isolates from Korea and also a reference strain. Overall, a total of 37 sequence types (STs) and six clonal complexes (CCs) were identified among the 82 K. pneumoniae isolates. The result of MLST analysis was concordant with that of pulsedfield gel electrophoresis. Most of the outbreak isolates belonged to a certain clone (ST2), and they produced SHV-1 and CTX-M14 enzymes, which was a different feature from that of the K. pneumoniae isolates from other Korean hospitals (ST20 and SHV-12). We also found a different distribution of CCs between ESBL-producing and -nonproducing K. pneumoniae isolates. The MLST method we developed in this study could provide unambiguous and well-resolved data for the epidemiologic study of K. pneumoniae. The outbreak isolates showed different molecular characteristics from the other K. pneumoniae isolates from other Korean hospitals.
Electrophoresis, Gel, Pulsed-Field ; Hospitals ; Humans ; Klebsiella pneumoniae/*classification/enzymology/genetics/isolation & purification ; Sequence Analysis, DNA ; beta-Lactamases/*biosynthesis ; Mycobacteria, Atypical/*drug effects/genetics/isolation & purification

To produce TEM-116 extended-spectrum beta-lactamase (ESBL) from recombinant bacteria in a cost-effective way, we purified and renatured the recombinant TEM-116 ESBL from the inclusion bodies by Ni(2+)-NTA affinity and gel filtration chromatography through subcloning the bla(TEM-116) into expression vector pET28a(+), transforming into Escherichia coli BL21(DE3) and inducing with IPTG. We characterized the purified protein that had the molecular weight of 30 kDa and specific activity of 476 IU/mg. The recombinant TEM-116 ESBL showed higher efficiency in eliminating penicillin and cephalosporin in vitro and in vivo. Specifically, the recombinant TEM-116 ESBL could eliminate 7000 mg penicillin G (PG) when used at 10.0 IU in 1 L fermentation medium. When used at 320.0 IU, it could also degrade a mix of PG, ampicillin and cefazolin each at 200 mg in 1 L of urine. In milk, 1.0-2.5 IU of the recombinant enzyme could remove 80 U/L of PG. The recombinant enzyme was fully active at the temperature ranged from 4 degrees C to 37 degrees C. Furthermore, the recombinant enzyme used at 2.0x10(4)-2.3x10(4) IU/(kg bw) (body weight) eliminated 8.0x10(4)-9.1x10(4) microg/(kg bw) PG in mouse models in vivo. The recombinant TEM-116 ESBL has the potential as a tool enzyme in food and environmental protection to eliminate harmful residues of antibiotics.
Animals ; Cephalosporins ; antagonists & inhibitors ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; genetics ; Mice ; Penicillins ; antagonists & inhibitors ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; pharmacology ; beta-Lactamases ; biosynthesis ; genetics ; isolation & purification