BL-S640, a new oral cephalosporin analogue, was evaluated in vitro against 102 gram-negative and 80 gram-positive bacteria. The antimicrobial spectrum was similar to that of previous cephalosporin analogues. Good antimicrobial activity against strains of Escherichia coli, Klebsiella, staphylococci, and streptococci was demonstrated. Relatively poor activity and/or resistance was noted among mos...

An early blocked sulfur amino acid auxotroph, Cephalosporium acremonium mutant 274-1 (which could be satisfied by methionine or cysteine), utilized organic sulfur compounds for cephalosporin C production in the following order of decreasing effectiveness; methionine > cystathionine > cysteine, despite the fact that cysteine is considered to be the immediate precursor of the antibiotic. When a g...

Recent studies have suggested that combination antibiotic therapy is preferable to monotherapy for severe community-acquired pneumonia (CAP). In this issue Mortensen and colleagues present retrospective data suggesting that combination therapy with a cephalosporin and a fluoroquinolone is inferior to combination therapy with a cephalosporin and a macrolide. Several mechanisms exist by which qui...

Extended-spectrum-cephalosporin-resistant Enterobacteriaceae are a public health concern due to limited treatment options. Here, we report on the occurrence and the molecular characteristics of extended-spectrum-cephalosporin-resistant Enterobacteriaceae recovered from wild birds (kelp gulls). Our results revealed kelp gulls as a reservoir of various extended-spectrum cephalosporinase genes ass...

Using two different molecular orbital methods which treat all valence electrons, namely extended Huckel theory and CNDO/2,a correlation has been found between the biological activity of cephalosporin derivatives and certain aspects of the electronic structure of the /3lactam ring. Electron populations of the carbonyl carbon and bond strength indices of both the carbonyl carbon-nitrogen bond and...

In a previous paper3), we reported on the synthesis and the biological activity of 3-methoxymethyl cephalosporin derivatives, one of which, cefpodoxime proxetil (Fig. 1), has been successfully developed as a prodrug for oral use. Our further elaboration for developing orally active cephalosporins has been made in the direction of chemical modification of the C-7 acyl substituent of the 3-methox...

CTX-M-1-producing Escherichia coli were isolated from 56 pigs, three farm personnel, two manure samples, and two air samples from two Danish pig farms where an association between prophylactic ceftiofur use and the occurrence of cephalosporin resistance was previously demonstrated. Human, animal, and environmental strains displayed high genetic diversity but harbored indistinguishable or closel...

We report expanded-spectrum cephalosporin resistance in Escherichia coli from dogs and cats in Rome, Italy. Three major beta-lactamases (CMY-2, SHV-12, and CTX-M-1) are reported for the first time in E. coli from sick and healthy dogs and cats. Molecular characterization suggests the presence of several combinations of beta-lactamase genes in E. coli from companion animals.

The emergence of ciprofloxacin resistance in Shigella has shifted the attention to cephalosporins. The first occurrence of third generation cephalosporin-resistant Shigella flexneri was from France. This article reports the first case of cephalosporin-resistant S. flexneri from India. A 12-month-old child was admitted for a 20-day episode of loose stools, non-fetid, with mucus and blood. The st...