In the title compound, C(38)H(42)N(4)O(4)·C(2)H(6)O, prepared via a spiro-lactam ring-formation reaction in a rhodamine dye, the xanthene ring system is approximately planar (r.m.s. deviation = 0.0014Å) and subtends dihedral angles of 88.10 (3) and 86.92 (4)° with the spiro-lactam (r.m.s. deviations = 0.0012 Å) and benzene rings, respectively. The crystal structure consists of chains parallel t...

Background The beta lactam antibiotics are predominant therapeutic agents against a number of infectious diseases. The production of the enzyme beta lactamase by microbes which hydrolyses the beta lactam antibiotics is an important mechanism of resistance. This study aimed to determine prevalence, phenotypic patterns, and ESBLproduction status both phenotypic and genotypic for the CTX –M type E...

A temperature-sensitive mutant, strain SS, which is assumed to be devoid of beta-lactamase activity and deficient in a permeability barrier to antibiotics, was isolated from a beta-lactamase-less mutant, strain L-2, derived from Pseudomonas aeruginosa IFO 3080. By comparing the beta-lactam antibiotic susceptibility between strains IFO 3080, L-2, and SS, the involvement of both beta-lactamase an...

The very sensitive and specific method for the detection of beta-lactam antibiotics using DD-carboxypeptidase (DDCase) from Actinomadura strain R39 has been improved to meet the requirements of a high-throughput beta-lactam screening from culture broths of microorganisms. The method is based on a novel chromophor-labeled substrate N alpha-acetyl-N epsilon-4-(7-nitrobenzofurazanyl)-L-lysyl-D-al ...

A rapid and specific high-performance liquid chromatography method with UV detection (HPLC-UV) for the simultaneous determination of 12 beta-lactam antibiotics (amoxicillin, cefepime, cefotaxime, ceftazidime, ceftriaxone, cloxacillin, imipenem, meropenem, oxacillin, penicillin G, piperacillin, and ticarcillin) in small samples of human plasma is described. Extraction consisted of protein precip...

β-Lactam antibiotics have long been a treatment of choice for bacterial infections since they bind irreversibly to Penicillin-Binding Proteins (PBPs), enzymes that are vital for cell wall biosynthesis. Many pathogens express drug-insensitive PBPs rendering β-lactams ineffective, revealing a need for new types of PBP inhibitors active against resistant strains. We have identified alkyl boronic a...

This study was undertaken to investigate drug resistance in Escherichia coli (E. coli) strains isolated from bamboo rats in Zhejiang province of China. One hundred and fifty-four E. coli strains were isolated from dead bamboo rats. Polymerase chain reaction (PCR) was used to detect the representative genes encoding resistance to commonly used β-lactam antibiotics. Highest resistance was observe...

We report here a total synthesis of nocardicin A. The antibiotic was obtained as a mixture of diastereoisomers that possessed approximately one quarter of the antibacterial activity of the naturally occurring material. Recently a new B-lactam antibiotic, nocardicin A, has been reported.1,2) This is the first example of a monocyclic B-lactam derivative having antimicrobial activity. We report he...

The purpose of this study was to investigate the presence of beta-lactam-resistant bacteria in six different types of Portuguese cheese. The numbers of ampicillin resistant (AMP(r)) bacteria varied from 4.7 x 10(2) to 1.5 x 10(7) CFU/g. Within 172 randomly selected beta-lactam-resistant bacteria, 44 resistant phenotypes were found and 31.4% were multidrug resistant. The majority (85%) of the is...

The in vitro antibacterial activity of four beta-lactam antibiotics (cefatrizine [BL-S640], cefamandole, cefoxitin, and carbenicillin) and three aminoglycosides (amikacin, gentamicin, and tobramycin) was determined against 197 strains of cephalothin-resistant Enterobacteriaceae. Eighty strains were found to be gentamicin-sensitive, and 117 were found to be gentamicin-resistant. Carbenicillin wa...