Penicillins and cephalosporins are β-lactam antibiotics widely used in human medicine. The biosynthesis of these compounds starts by the condensation of the amino acids L-α-aminoadipic acid, L-cysteine and L-valine to form the tripeptide δ-L-α-aminoadipyl-l-cysteinyl-D-valine catalysed by the non-ribosomal peptide 'ACV synthetase'. Subsequently, this tripeptide is cyclized to isopenicillin N th...

PURPOSE Antimicrobial resistance monitoring could be a useful source of information for treating and controlling nosocomial infections. We analyzed antimicrobial resistance data generated by Korean Hospitals and by a commercial laboratory in 2005 and 2007. MATERIALS AND METHODS Susceptibility data for 2005 and 2007 were collected from 37 and 41 hospitals, respectively, and from one commercial...

Chapter 1 is devoted to the Bacitracins, a remarkable group of polypeptides containing the thiazoline nucleus. With the exception of Lyman C. Craig of the Rockefeller Institute, no one has done as much as Abraham to advance our knowledge of the nature of these substances, the structure of which is now, except for a few details, completely established. In Chapter 2 the author discusses the chemi...

There are reports of failure of extended-spectrum cephalosporin treatment in pneumococcal meningitis. On the basis of in vitro and animal experimental studies, the addition of vancomycin or rifampin to an extended-spectrum cephalosporin has been recommended for empiric treatment of these patients. Cerebrospinal fluid (CSF) was taken from 31 children with bacterial meningitis randomized to recei...

Proteus mirabilis, Proteus vulgaris, Morganella morganii, Providencia rettgeri, and Providencia alcalifaciens, which were once classified into the same genus, Proteus, were studied. Cefoxitin-resistant mutants from these species were isolated, and it was confirmed that the resistance was attributed to the lack of an outer membrane protein, resulting in a significant decrease in the penetration ...

A cross sectional prospective study was carried out to determine the prevalence of demographic status associated with pet owners and animals, pattern drugs used in prescription during period from February 2019 April at Central Veterinary Hospital (CVH), Dhaka, Bangladesh. total 493 clinical cases were analyzed found that educated illiterate calculated as 64.2% 13.8% dog owners, 89.4% 10.6% cat ...

1. The production of penicillin N, but not that of cephalosporin C, was inhibited by the addition of d-valine to suspensions in water of washed mycelium of Cephalosporium sp. 8650. The production of cephalosporin C was selectively inhibited by gamma-hydroxyvaline. 2. l-[(14)C]Valine was taken up rapidly and virtually completely by suspensions of washed mycelium but d-[(14)C]valine and alpha-oxo...

INTRODUCTION .......................................................................................................................................................547 GENERAL ASPECTS OF b-LACTAM COMPOUNDS........................................................................................548 BIOSYNTHESIS OF PENICILLINS AND CEPHALOSPORINS: AN OUTLINE.............................................

The peptidoglycan cell wall is a common target for antibiotic therapy, but its structure and assembly are only partially understood. Peptidoglycan synthesis requires a suite of penicillin-binding proteins (PBPs), the individual roles of which are difficult to determine because each enzyme is often dispensable for growth perhaps due to functional redundancy. To address this challenge, we sought ...