The mecA-27r gene from Staphylococcus aureus 27r encodes penicillin-binding protein 2a (PBP2a-27r), which causes this strain to be methicillin resistant. Removal or replacement of the N-terminal transmembrane domain had no effect on binding of penicillin, but removal of portions of the putative transglycosylase domain (144, 245, or 341 amino acids after the transmembrane region) destroyed penic...

Rationale Penicillin and other beta-lactams are the most commonly used antibiotics due to their narrow spectrum of activity, low cost and safety profile. However, an “allergy” to Penicillin is also the most commonly reported allergy. Approximately, 5-10% of all patients self-report an allergy to Penicillin and of these <10% are found to have true IgE mediated allergy on skin testing. Numerous s...

Penicillin kills susceptible bacteria by specifically inhibiting the transpeptidase that catalyzes the final step in cell wall biosynthesis, the cross-linking of peptidoglycan. It was hypothesized (Tipper, D., and Strominger, J. (1965) Proc. Natl. Acad. Sei. U. S. A. 64,11331141) that 1) penicillin is a structural analog of the acylD-alanyl-D-alanine terminus of the pentapeptide side chains of ...

The action and interaction of benzylpenicillin and gentamicin on Streptococcus faecalis was studied using mainly turbidimetric methods. The minimum antibacterial concentration (MAC) of each antibiotic lay considerably below the conventionally determined minimum inhibitory concentration, and levels of the two agents exceeding the MAC were necessary in order to obtain a synergic interaction. Evid...

Some biochemical properties of whole-cell penicillin amidohydrolase from Micrococcus luteus have been studied. This whole-cell enzyme showed its maximal activity at 36 degrees C at pH 7.5. It was found that the activation energy of this enzyme was 8.03 kcal (ca. 33.6 kJ) per mol, and this amidohydrolase showed first-order decay at 36 degrees C. The penicillin amidohydrolase was deactivated rapi...

Linear regression analysis was used to compare penicillin MICs determined with 3,129 recent clinical isolates of Streptococcus pneumoniae to MICs obtained with nine other beta-lactam antimicrobial agents. A strong correlation between penicillin MICs and those obtained with other beta-lactams was demonstrated. It may be possible to test penicillin and use MICs obtained with penicillin to predict...

Linear regression analysis was used to compare penicillin MICs determined with 3,129 recent clinical isolates of Streptococcus pneumoniae to MICs obtained with nine other beta-lactam antimicrobial agents. A strong correlation between penicillin MICs and those obtained with other beta-lactams was demonstrated. It may be possible to test penicillin and use MICs obtained with penicillin to predict...