Sir Richard Sykes presented this Friday Evening Discourse at the Royal Institution of Great Britain on Friday 6 May 2011. Microbes have evolved over 3.5 billion years and are arguably the most adaptable organisms on earth. Restricted genetically by their inability to reproduce sexually, bacteria have acquired several additional mechanisms by which to exchange genetic material. Such mechanisms have allowed bacteria to inhabit some of the most inhospitable environments on earth. It is then hardly surprising that when faced with a barrage of inimical chemicals (antibiotics) they have responded with an equal and opposite force. Sir Richard compared and contrasted the evolution of antimicrobial resistance to B-lactam antibiotics over the last 70 years in two bacterial species, namely Staphylococcus aureus, a highly evolved human pathogen, and Pseudomonas aeruginosa, an opportunistic nosocomial pathogen. Find out more at www.rigb.org

6. Meiosis

7. Binary fission

8. Deep sea vent

13. Conjugating bacteria

14. Staphylococcus aureus

16. Gram positive cell wall Carboxypeptidase Transpeptidase

17. 1 Penicillin sensitive enzymes, involved in cell wall biosynthesis GlcNAc MurNAc GlcNAc MurNAc GlcNAc MurNAc L - Ala D - Glu meso - DAP D - Ala L - Ala D - Glu meso - DAP - ? - NH 2 D - Ala L - Ala D - Glu meso - DAP D - Ala D - Ala DD - Carboxypeptidase LD - Carboxypeptdase D - Ala meso - DAP D - Glu L - Ala MurNAc D - Ala meso - DAP D - Glu L - Ala MurNAc GlcNAc GlcNAc Transpeptidase

18. Structure of cell wall peptide and pencillin

20. Gram positive cell wall . .

21. Inactivation of Penicillin by B- Lactamase

22. Bacteriophage

23. Gram positive cell wall Transpeptidase B-lactamase

24. Bacterial Plasmids

25. Semi synthetic penicillins 6-APA Methicillin Cloxacillin

27. Necrotising Fascilitis

28. Gram positive cell wall Transpeptidase B-lactamase

29. Cephalasporin C – 7-ACA (capital c) Cephalosporin C 7- Aminocephalosporanic acid (7-ACA)

31. Clavulanic acid

33. Pseudomonas aeruginosa

34. Pseudomonas infection

35. Pseudomonas cell wall B-lactamase Transpeptidase

37. Antibiotic efflux Efflux Pump

38. Pseudomonas cell wall B-lactamase Transpeptidase

39. Carbenicillin

40. Ceftazidine