Antibiotic chemistry 2

• What is the combination of antibiotics mentioned in the study material?

  CEPHALOSPORIN + COPLAMYCIN
• Why are cephalosporins used in patients who are resistant to penicillins?

  They are often used in patients who are resistant to penicillins.
• How can semi-synthetic cephalosporins be made?

  By using acylation to remove certain groups.
• What is a notable characteristic of cephalosporins in clinical use?

  They are generally preferred in clinical treatment despite some resistance.
• What adverse effect is associated with cephaloridine?

  It causes nephrotoxicity.
• What problem is associated with beta-lactam antibiotics?

  Beta-lactamase problem.
• What does cephalosporin undergo during hydrolysis?

  It undergoes hydrolysis of the cephalosporin structure.
• What is a strategy for overcoming resistance to cephalosporins?

  Charge modification of the molecule.
• What is the effect of rapid resistance development on cephalosporins?

  It leads to open treatment solutions due to rapid resistance.
• How does charge affect the efficacy of antibiotics like cephalosporins?

  Charge affects how the antibiotic interacts with bacterial membranes.
• What is the name of the antibiotic class that includes cephalosporins?

  Beta-lactams
• What is the role of acylation in the synthesis of cephalosporins?

  It is used to modify the structure of cephalosporins.
• What happens to cephalothin during metabolism?

  It undergoes rapid metabolism, removing the acyl group.
• What is the significance of cephalosporins being almost completely avoided in certain instances?

  It indicates their limited effectiveness in those cases.
• What is the purpose of administering a β-lactamase inhibitor?

  To enhance the effectiveness of β-lactam antibiotics like penicillin
• Why is penicillin sometimes considered poor in resonance multiple cells?

  Because it may not be effective against all bacterial strains
• What is a suicide inhibitor in the context of antibiotics?

  An inhibitor that irreversibly binds to an enzyme, preventing its function
• What happens to the substrate in the presence of a suicide inhibitor?

  The substrate undergoes a reaction that regenerates reactive species that inactivate lactamase
• Name two examples of irreversible β-lactamase inhibitors.

  Sulbactam and tazobactam
• How do β-lactamase inhibitors interact with penicillinase?

  Each inhibitor behaves as a substrate and reacts with the penicillinase active site residue
• What is the result of the rearrangement of the acyl-enzyme intermediate?

  It leads to the inactivation of the enzyme
• Why are most β-lactamase inhibitors not effective in vivo?

  Due to rapid inactivation and difficulties penetrating the bacterial cell wall
• What is the primary function of clavulanic acid?

  To irreversibly inhibit class A penicillinases
• How does clavulanic acid affect penicillin's effectiveness?

  It increases the effect of penicillin by preventing degradation by β-lactamases
• With which antibiotic is clavulanic acid normally co-administered?

  Amoxicillin
• Against which class of penicillinases is clavulanic acid effective?

  Class A (metal-independent) penicillinases
• Why is clavulanic acid inactive against class C or D penicillinases?

  Because it cannot form a covalent bond with the enzyme
• How does co-amoxiclav help overcome bacterial penicillin resistance?

  By reducing the release of bacteria producing clavulan when they are not activated by it
• What effect does clavulanic acid have on the acylation efficiency of β-lactamase?

  It irreversibly reacts and reduces the acylation efficiency
• Which classes of β-lactamases are not inactivated by clavulanic acid?

  Class B, C, and D β-lactamases