Clinical Oligella urethralis isolate COH-1, which was uncommonly resistant to penicillins and narrowspectrum cephalosporins, was recovered from a 55-year-old patient with a urinary tract infection. Shotgun cloning into Escherichia coli and expression experiments gave recombinant clones expressing either an AmpC -lactamase-type phenotype of resistance or a carbenicillin-hydrolyzing -lactamase-ty...

The main objective of this study was to investigate the epidemiology, drug resistance and β-lactamase genotype distribution of enteropathogenic Escherichia coli (EPEC) isolated from pediatric patients with diarrhea in southern China. The prevalence of EPEC in children with diarrhea was 3.53%. The commonest serotypes were O55:K59 and O126:K71, and the typical EPEC were more prevalent than atypic...

A 19 kb SphI DNA fragment containing the gene for the extracellular active-site serine Q-lactamase of Streptomyces cacaoi KCC-SO352 was cloned in Streptomyces liuidans TK24 using the high-copy-number plasmid pIJ702 as vector. A 30-fold higher yield of P-lactamase was obtained from S. lividans strain ML1, carrying the recombinant plasmid pDML51, than from S. cacaoi grown under optimal production...

AIM The aim of this study was to characterize beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh. MATERIALS AND METHODS A total of 136 rectal swabs were collected from healthy (92) and diarrheic (44) dogs, bacteriological cultured for Klebsiella and Enterobacter growth and screened for beta-lactamase antimi...

A restriction map of a 13.5-kb EcoRI fragment encoding beta-lactamase from a plasmid isolated from enterococcal strain PA was prepared and found to differ markedly from the published maps of beta-lactamase-encoding EcoRI fragments of two staphylococcal plasmids and the plasmid from enterococcal strain HH22. This comparison also showed that one of two contiguous EcoRV fragments that encompass th...

Four beta-lactamase-producing clinical isolates (WH245, WH257, CH570, and DEL) of Enterococcus faecalis were examined for the presence of the staphylococcal beta-lactamase regulatory genes (blaR1 and blaI) by PCR using six primer pairs. All isolates produced small amounts of beta-lactamase constitutively. In WH245, CH570, and DEL, the corresponding regions of the regulatory genes have lost sequ...

Intraperitoneal injections of 250 mg of ampicillin per kg every 6 h for 30 h sterilized the blood and cerebrospinal fluid of infant rats infected with either a beta-lactamase-containing strain of Haemophilus influenzae type b or a strain lacking the enzyme. However, a single injection of 100 mg/kg sterilized the blood and cerebrospinal fluid of significantly fewer of those rats infected with th...

Two fi-lactamase-producing strains of Neisseria gonorrhoeae were studied. The substrate profile, molecular weight, and isoelectric point of their ,8-lactamases were similar to those of the TEM-1 enzyme produced by many gram-negative bacilli. The gonococcal f8-lactamase was cell bound during exponential growth and was most likely located in the periplasm. Penicillin hydrolysis was efficient in i...

β-Lactamase residues in milk represent a public health risk. The cylinder plate detection method, which is based on bacterial growth, is laborious and time consuming. In this study, 15 monoclonal antibodies (mAbs) were selected against Temoneira (TEM) 1 β-lactamase. A sandwich enzyme-linked immunosorbent assay (ELISA) based on an optimum mAb pair was developed and validated for the detection of...

Several beta-lactamases, enzymes that play an important part in antibiotic resistance, have been purified by affinity chromatography on boronic acid gels. The procedure is rapid, appears to be selective for beta-lactamases, and allows a one-step purification of large amounts of enzyme from crude cell extracts. We have found the method useful for any beta-lactamase that is inhibited by boronic a...