Paper II — 2014 March (2010 Scheme) — Q1

Paper II

2014 March (2010 Scheme) · 40 marks · 120 min

Question

Enumerate the antibiotics which act by inhibiting cell wall synthesis. Mention the detailed mechanism of action of any one of them on bacterial cell wall synthesis. Add a note on beta lactamase inhibitors (2 + 2 +2 = 6)

Q16 marksEssays★✓

Answer

Antibiotics inhibiting cell wall synthesis

• Penicillins (Penicillin G, Amoxicillin, Piperacillin)
• Cephalosporins
• Carbapenems (Imipenem, Meropenem)
• Monobactams (Aztreonam)
• Vancomycin
• Bacitracin

Mechanism of action (Penicillins)

• Bacterial cell wall peptidoglycan is cross-linked by transpeptidase enzymes (“penicillin-binding proteins,” PBPs)
• Penicillins structurally resemble the terminal D-alanyl-D-alanine of the peptidoglycan pentapeptide and bind irreversibly to PBPs, inhibiting the transpeptidation (cross-linking) reaction
• This weakens the cell wall, and along with activation of autolytic enzymes, causes bacterial cell lysis (bactericidal), particularly in actively dividing cells

Note on beta-lactamase inhibitors

• Clavulanic acid, Sulbactam, Tazobactam
• Themselves possess weak/no antibacterial activity but irreversibly inhibit bacterial beta-lactamase enzymes, which would otherwise hydrolyse and inactivate the beta-lactam ring of penicillins
• Combined with beta-lactam antibiotics (e.g., Amoxicillin-clavulanate, Piperacillin-tazobactam) to extend their spectrum to beta-lactamase-producing organisms

Related Concepts

1. 1Beta Lactam Antibiotics

Other Years Asked

1. 1(2022 February (2019 Scheme)Essay · 12 marks
2. 2Enumerate Cephalosporins. Describe their mechanism of action, uses and adverse effects of third generation Cephalosporins. (4+4)2023 January (Supplementary) (2019 Scheme)Short Essay · 8 marks
3. 3(2024 June (Supplementary) (2019 Scheme)Short Essay · 8 marks
4. 4Classify cephalosporins. Describe the mechanism of action and clinical uses of ceftriaxone. Which drug can be combined with amoxicillin to treat infection due to beta lactamase producing staph. aureus. ( 2+1+2+1 = 6)2016 February (2010 Scheme)Essay · 6 marks
5. 5Classify beta lactam antibiotics. Explain the mechanism of action, uses and adverse effects of ceftriaxone. (2+2+1+1)2018 July (Supplementary) (2010 Scheme)Essay · 6 marks
6. 6Classify cephalosporins. Mention the mechanism of action, adverse effects and uses of third generation cephalosporin. (2+2+2=6)2017 February (2010 Scheme)Essay · 6 marks
7. 7A 50 years old lady complains of pain in the throat and has been diagnosed to have streptococcal tonsillitis. Answer the following:2016 October (Supplementary) (2010 Scheme)Essay · 6 marks
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10. 10III generation cephalosporin2023 March (Supplementary) (2010 Scheme)Short Note · 3 marks
11. 11Second generation cephalosporins and its uses.2013 September (Supplementary) (2010 Scheme)Short Note · 3 marks
12. 12Penicillin2025 March (Supplementary) (2010 Scheme)Short Note · 3 marks
13. 13Beta-Lactamase inhibitors2021 May (Supplementary) (2010 Scheme)Short Note · 3 marks
14. 14Specify the important spectrum of ciprofloxacin.2017 February (2010 Scheme)Short Answer · 1 mark
15. 15Anti pseudomonal drugs2014 March (2010 Scheme)Short Answer · 1 mark
16. 16Metronidazole and ceftriaxone for brain abscess2020 February (Supplementary) (2010 Scheme)Short Answer · 1 mark
17. 17Cotrimoxazole is NOT effective against infections caused by:2024 December (Supplementary) (2019 Scheme)MCQ · 1 mark
18. 18Use of Clavulanic acid with Amoxicillin.2024 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
19. 19Combination of Amoxicillin and Clavulanic acid2025 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
20. 20Assertion (A): Vancomycin is used primarily to treat infections caused by Methicillin-resistant Staphylococcus aureus (MRSA). Reason (R): Vancomycin inhibits the formation of bacterial cell walls by binding to D-alanyl- D-alanine, a component of the peptidoglycan precursor.2025 March (Supplementary (SAY)) (2019 Scheme)MCQ (A/R) · 1 mark
21. 21Amoxicillin with clavulanic acid2019 February (2010 Scheme)Short Answer · 1 mark
22. 22Pharmacological basis for combining beta lactamase inhibitors with beta lactam antibiotics.2017 February (2010 Scheme)Short Answer · 1 mark
23. 23The potent inhibitor of bacterial cell wall synthesis used for Neisseria gonorrhoeae infections is:2025 March (Supplementary (SAY)) (2019 Scheme)MCQ · 1 mark
24. 24Gentamicin2024 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
25. 25Mention anti pseudomonal penicillins2013 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
26. 26Cilastatin with Imipenem2022 May (Supplementary) (2010 Scheme)Short Answer · 1 mark
27. 27Gram negative septicemia2014 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
28. 28Clavulanic acid with Amoxicillin2023 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
29. 29Tocolytics2020 February (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
30. 30Antipseudomonal cephalosporins2021 May (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
31. 31Third generation cephalosporins2024 August (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
32. 32 Fourth generation cephalosporins in MRSA infection2019 July (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
33. 33Drugs effective against both gram positive & gram negative organisms2019 February (2010 Scheme)Short Answer · 0.3 marks
34. 34Anti-seborrheic agents2019 February (2010 Scheme)Short Answer · 0.3 marks
35. 35Iron chelators2021 May (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
36. 36Anticancer antibiotics2021 December (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
37. 37Drugs used in Penicillinase producing staphylococcal infections.2022 July (Supplementary) (2019 Scheme)Short Answer · 0.2 marks