Penicillin-resistant mutants of Staphylococcus aureus H were similar to the parent in their response to penicillin though proportionately more penicillin was required for a given effect. The mutants did not inactivate penicillin. Most of the penicillin-binding sites (presumed to be murein transpeptidase molecules) bound penicillin rapidly when exposed to a very low concentration of penicillin (...

CONTEXT Clinicians frequently withhold antibiotics that contain penicillin based on patients' self-reported clinical history of an adverse reaction to penicillin and the clinicians' own misunderstandings about the characteristics of a true penicillin allergy. OBJECTIVES To determine the likelihood of true penicillin allergy with consideration of clinical history and to evaluate the diagnostic...

Non-beta-lactamase-producing, penicillin-resistant strains of Neisseria meningitidis produce altered forms of penicillin-binding protein 2 that have decreased affinity for penicillin. The sequence of the penicillin-binding protein 2 gene (penA) from a penicillin-resistant strain of N. meningitidis was compared to the sequence of the same gene from penicillin-sensitive strains and from penicilli...

Penicillin acylase (EC 3.5.1.11) has been a target of study for a long time because of its pivotal role in the deacylation of the penicillin into the 6- aminopenicillanic acid (6-APA) and the side-chain organic acids. This property of penicillin acylase has been exploited commercially for large scale production of 6-APA, which is the key intermediate in the manufacture of semi-synthetic penicil...

Individual approaches to the diagnosis and management of penicillin allergy are practiced    by clinicians.   This cross-sectional survey of physicians was aimed at exploring their ways of dealing with diagnosis and management of penicillin G allergy.   Of the 235 respondents, 63% believed patients’ self-reported history of penicillin allergy and avoided using penic...

Penicillin-resistant and penicillin-tolerant mutants have been isolated from group A streptococci mutagenized by ethyl methane sulfonate. The resistant mutants had an elevated minimal growth inhibitory concentration for benzylpenicillin (minimal inhibitory concentration, 0.2 microgram/ml, as compared with the minimal inhibitory concentration of 0.006 microgram/ml in the penicillin-susceptible p...

BACKGROUND A history of penicillin allergy in patients is common, but only 10-15 % are truly allergic. While the gold standard for diagnosing penicillin allergy is challenge, it is not recommended that this be done without first carrying out diagnostic skin testing. This is carried out with the major determinant benzylpenicilloyl (PPL) and the minor determinant mixture (MDM), consisting of peni...

BACKGROUND Penicillin allergy is the most commonly reported drug allergy and often presents with cutaneous symptoms. Other common diagnoses, such as chronic urticaria, may be falsely attributed to penicillin allergy. Because chronic urticaria is fairly common in the general population, evaluation of its prevalence in patients with self-reported penicillin allergy was of interest. Similarly, the...