Related Experiment Videos
Apalcillin [PC-904]: spectrum of activity and beta-lactamase hydrolysis/inhibition
Abstract:
Apalcillin is a Pseudomonas-active penicillin with a broad spectrum of antibacterial activity similar to that of piperacillin, except for the greater potency of apalcillin against Acinetobacter spp. and Pseudomonas aeruginosa. Studies with 846 isolates representative of the common bacterial pathogens compared apalcillin to piperacillin, azlocillin, mezlocillin, carbenicillin, ticarcillin, cefotaxime, and cefoperazone. Apalcillin and piperacillin were both active against all 13 species of the Enterobacteriaceae that were tested (MIC 50s less than or equal to 8.0 micrograms/ml) but some strains were resistant to both penicillins. Apalcillin was active against Pseudomonas aeruginosa and Acinetobacter spp. (MIC 50 less than 2.0 micrograms/ml). Like other penicillins, apalcillin was not effective against beta-lactamase-producing Staphylococcus spp., Haemophilus spp. or Neisseria gonorrhoeae. Rates of hydrolysis by six beta-lactamase preparations from gram-negative bacilli were determined, comparing apalcillin, piperacillin, azlocillin, ticarcillin, ampicillin and dicloxacillin to benzyl penicillin. Apalcillin and ticarcillin were more resistant than piperacillin and azlocillin to hydrolysis by the PSE-2 enzyme from P. aeruginosa. As did many other penicillins, apalcillin inhibited the Type 1 beta-lactamase that is produced by Enterobacter cloacae. The other enzymes were inhibitory only in very high concentrations.
Insights
Apalcillin demonstrates potent activity against Pseudomonas aeruginosa and Acinetobacter species, similar to piperacillin but with enhanced efficacy. It shows broad-spectrum antibacterial action but is ineffective against certain resistant bacteria.
Area of Science:
- Microbiology
- Pharmacology
- Infectious Diseases
Background:
- Apalcillin is a penicillin antibiotic with broad-spectrum antibacterial activity.
- Its efficacy is comparable to piperacillin, with notable differences in potency against specific pathogens.
Purpose of the Study:
- To evaluate the antibacterial spectrum and potency of apalcillin.
- To compare apalcillin's activity against common bacterial pathogens with other penicillins and cephalosporins.
- To assess apalcillin's susceptibility to hydrolysis by beta-lactamase enzymes.
Main Methods:
- In vitro susceptibility testing of 846 bacterial isolates against apalcillin and comparator agents.
- Determination of hydrolysis rates using six beta-lactamase preparations from gram-negative bacilli.
Main Results:
- Apalcillin exhibited potent activity against Pseudomonas aeruginosa and Acinetobacter spp. (MIC50 < 2.0 µg/ml).
- Both apalcillin and piperacillin were active against Enterobacteriaceae, though some strains showed resistance.
- Apalcillin demonstrated greater resistance to PSE-2 beta-lactamase compared to piperacillin and azlocillin.
Conclusions:
- Apalcillin is a potent Pseudomonas-active penicillin with a broad spectrum of activity.
- Its enhanced potency against Acinetobacter spp. and Pseudomonas aeruginosa makes it a valuable therapeutic option.
- Apalcillin's stability against certain beta-lactamases contributes to its efficacy.