beta-lactams are a group of antibiotics with a broad spectrum of both gram-negative and gram-positive coverage. the goal of this study is to evaluate the results from studies regarding ig-e mediated hypersensitivity to penicillin and cross-reactivity with other beta-lactams. review was conducted of both retrospective and prospective studies by searching in pubmed and medline for the original an...

The interactions between imipenem and four monobactams and three class A beta-lactamases have been studied in detail. Despite their reputation as being beta-lactamase-stable, some of these compounds were significantly hydrolysed by the enzymes. The results obtained with the Streptomyces albus G beta-lactamase have been analysed in the light of molecular modelling studies. The discussion is exte...

INTRODUCTION................................................................. 13 PRECLINICAL TESTING STAGES ................................................................. 13 Discovery of New Antibiotics ................................................................. 13 Establishment of SAR ................................................................. 15 Animal Models for Studying the P...

Resistance to β-lactams is constantly increasing due to the emergence of totally new enzymes but also to the evolution of preexisting β-lactamases. GES-1 is a clinically relevant extended-spectrum β-lactamase (ESBL) that hydrolyzes penicillins and broad-spectrum cephalosporins but spares monobactams and carbapenems. However, several GES-1 variants (i.e., GES-2 and GES-5) previously identified a...

Definitions: Beta-lactam antimicrobials are characterized by having a four-membered cyclic amide (beta-lactam ring) as part of their chemical structure (Figure 1) [1]. This broad group includes the penicillins, cephalosporins, carbapenems, and monobactams [1]. All beta-lactams have a similar mechanism of action; they inhibit bacterial cell wall synthesis [1]. Resistance to beta-lactam antimicro...

Beta-lactamase enzymes (BLs) have become the most worrisome mediators of antimicrobial resistance expressed by gram-negative bacteria (GNB). The multiple families of BLs have in common the ability to hydrolyze the -lactam rings of one or more members of the penicillins, cephalosporins, cephamycins, carbapenems, and monobactams. Extended-spectrum -lactamases (ESBLs) are a subset of BLs that conf...

Beta-lactamase enzymes (BLs) have become the most worrisome mediators of antimicrobial resistance expressed by gram-negative bacteria (GNB). The multiple families of BLs have in common the ability to hydrolyze the -lactam rings of one or more members of the penicillins, cephalosporins, cephamycins, carbapenems, and monobactams. Extended-spectrum -lactamases (ESBLs) are a subset of BLs that conf...

The presence of a leaving group at C-4 of monobactams is usually considered to be a requirement for mechanism-based inhibition of human leukocyte elastase by these acylating agents. We report that second-order rate constants for the alkaline hydrolysis and elastase inactivation by N-carbamoyl monobactams are independent of the pKa of the leaving group at C-4. Indeed, the effect exerted by these...

BUMC PROCEEDINGS 2001;14:106–107 D uring a drug history, the most common drug allergies cited are those experienced after the administration of a penicillin, with a reported allergy incidence of 1% to 10% in patients who receive drugs in this class (1). Penicillins, as well as other beta-lactam antibiotics such as cephalosporins, carbapenems, and monobactams, contain a beta-lactam ring (2). The...