Course: Scientific Discovery Instructor: Dr. Alexandra Vankley Presentation By: Sri Ram 10/21/03

1. Course: Scientific Discovery Instructor: Dr. Alexandra Vankley Presentation By: Sri Ram 10/21/03

2. STORY OF PENCILLIN

3. Interesting Facts • The wonder drug • The first antibiotic popularly known • The first antibiotic produced and used on a massive scale • The pioneer of chemotherapy

4. The 2 parts of the story • a-the discovery of penicillin as an antibacterial and Alexander Fleming • b-the discovery and realization of its chemotherapeutic potential

5. Discovery of Penicillin

6. Background • Works of Louis Pasteur and Robert Koch, helped elucidate the connection between infectious diseases and the invasion of the body by bacteria and other micro-organisms .

7. Microbial Discoveries

8. Related Events • In 1871, Joseph Lister ( antiseptic practice surgery) - a mold in a sample of urine - inhibiting bacterial growth. • In 1875 John Tyndall - a species of Penicillium caused some of his bacteria to burst. • In 1877 Louis Pasteur and Jules Joubert -airborne microorganisms could inhibit the growth of anthrax bacilli .

9. Related Events contd. • Ernest Duchesne in 1897 focused on the interaction between E. coli and Penicillium glaucum . • Inoculating mold and typhoid bacilli -prevented contraction of typhoid in animals. But, he died of T.B before he could complete his research. • Experiments carried out by Emmerich and Loew (1899) and later by Gratia and Dath and others did not give any favorable results.

10. Related Events contd. • Instead various forms of vaccination and serum treatment were evolved. • The first Nobel Prize for Physiology or Medicine in 1901 was given for serum therapy for diphtheria. • Human and animal bodies - produce protective substances in the fight against the invaders.

11. Sir Alexander Fleming

12. Sir Alexander Fleming • Born on August 6th,1881 at Lochfield, Scotland in a farmer’s family . • He had his early days spent more in the farms but was sound in his fundamental education. • 1895-The untimely death of his father and the success of the medical practice of his step-brother Tom had him relocated to London.

13. Sir Alexander Fleming • 1895 –He attended the Polytechnic School in Regent Street . • 1896-1900- He worked as a clerk in a shipping firm. • 1900- In 1900, when the Boer War broke out joined the Scottish regiment but never saw the combat.

14. Sir Alexander Fleming • Later encouraged by his brother and supported by the money he received from an Uncle’s demise he looked towards a medical career. • 1901-He won a scholarship to St. Mary's Hospital Medical School, London University, Paddington and joined it. • He qualified with distinction and received his degree in 1906

15. Sir Alexander Fleming • His switch to bacteriology was even more surprising: if he took a position as a surgeon, he would have to leave St. Mary's. • The captain of St. Mary's rifle club knew that and was desperate to improve his team. Knowing that Fleming was a great shot he did all he could to keep him at St. Mary's. • He worked in the Inoculation Service and he convinced Fleming to join his department in order to work with its brilliant director -- and to join the rifle club.

16. Sir Alexander Fleming • 1906- Fleming joined the Inoculation Department as medical bacteriologist under the direction of Sir Almroth Wright. • He made the St. Mary's Hospital Medical School his professional home for the rest of his life. • 1914-Flemming became a lecturer at St.Mary’s. • 1914-1918- Served as Captain in W W 1 1906 he joined the staff of the

17. Sir Alexander Fleming • 1918 -He returned to St.Mary's. • 1928- He was elected Professor of the School in 1928 • 1943-He was elected Fellow of Royal Society. • 1944-Flemming was knighted. • 1945-Received his Nobel Prize.

18. 1948-Elected the Emeritus Professor of Bacteriology, University of London. • 1951-54-He was Rector of Edinburgh University. • Died on March 11th,1955

19. Fleming’s Ideology • Wright believed, as did Fleming, there were substances in the human body that could be used to fight infection, and strengthening the immune system was key. • Hence, they believed more on vaccine therapy rather than chemotherapy.

20. Ehrlich’s “Salvarsan” • In 1909 German chemist-physician Paul Ehrlich developed a chemical treatment for syphilis. • salvarsan - "that which saves by arsenic". • Ehrlich’s samples were given to Fleming by Wright and became efficient in its administration. • He did so with the new and difficult technique of intravenous injection. He soon developed such a busy practice he got the nickname "Private 606.“

21. Antiseptics of that period • During World War I- wound-research laboratory in Boulogne, France. • Chemical antiseptics like carbolic acid (phenol) do not sterilize jagged wounds; rather, pus has its own antibacterial powers. • He was able to show that chemical antiseptics in dilutions harmless to bacteria actually damage white blood corpuscles (leukocytes)—the body's first line of defense.

23. Lysozyme Discovery • Fleming looked for -a chemical like salvarsan, that could help fight microbe infections. • After war in 1920, back in St.Mary’s Fleming searched for an affective antiseptic. • He discovered Lysozyme, in nasal mucus . Its an enzyme found in many body fluid, like tears, etc. It is a natural antibacterial not effective against the stronger infectious agents.

24. Lysozyme’s Activity

25. Lysozyme • Lysozyme, in its natural state, seemed to be more effective against harmless airborne bacteria than against disease-causing bacteria. • And attempts to concentrate it, proved unsuccessful. • Fleming continued his research of finding a better and less toxic antiseptic and antibacterial.

26. The Chanced Discovery • Fleming's legendary discovery of penicillin occurred in 1928, while he was investigating staphylococcus, a common bacteria then caused diseases ranging from boils to disastrous infections.

27. Fleming at his usual work

28. The Halo of Pencillin • He left a culture plate smeared with Staphylococcus bacteria on his lab bench while he went on a two-week holiday. • When he returned, he noticed a clear halo surrounding the yellow-green growth of a mold that had accidentally contaminated the plate.

29. The Halo of Pencillin

30. The culture-plate

31. How This Happened • Luckily, Fleming had not stored his culture in a warm incubator. London was then hit by a cold spell, giving the mold a chance to grow. • Later, as the temperature rose, the Staphylococcus bacteria grew, covering the entire plate--except for the area surrounding the moldy contaminant.

32. Fleming’s Deduction • Fleming correctly deduced -mold must have released a substance - inhibited the growth of the bacteria. • He was never clear on his observations. The evidence of the first culture, which he photographed indicated that Fleming observed lysis, the weakening and destruction of bacteria—as in his lysozyme studies.

33. Penicillin and Lysozyme Activity

34. Fleming’s Deduction • But sometimes Fleming described it inhibition, or prevention of bacterial -evidenced by a clear zone surrounding the mold. • Although these two effects occur under quite different conditions, Fleming probably forgot which observation came first.

35. Penicillin Identified • He discovered that the antibacterial substance was not produced by all molds, only by strain of Penicillium notatum). • Although he could not isolate it, he named the active substance “penicillin.” • He studied methods of producing the impure product and determined its stability at different temperatures and over various lengths of time.

36. Penicillin is Non-Toxic • Fleming found that penicillin was not toxic to animals and that it did not harm white blood cells (leucocytes) by injecting healthy mice extract from the mold growth. • Previous, observations of such injections proved toxic and penicillin was an exception.

37. Penicillin Properties • Penicillin would not be absorbed if taken orally. • Penicillin taken by injection - excreted in the urine in a matter of hours-well before it could have its effects. • Moreover, the unstable penicillin was never available for clinical testing.

38. Fleming’s ways of using Penicillin • For Fleming, penicillin's therapeutic potential - topical antisepsis. • Fleming did continue to use in bacteriology. Penicillin suppressed the growth of certain bacterial species, allowing one to selectively culture certain others (such as those causing influenza, acne and whooping cough).

39. Selective Inhibition

41. Penicillin in vaccine production • Penicillin became a valuable in manufacture of vaccines. • The penicillin was crude--good enough for Fleming's purpose, but hardly strong enough to destroy a serious human infection.

42. Paper on Penicillin Little notice was taken by the scientific community of his paper published in the British Journal of Experimental Pathology (June 1929).

43. Explanation for Failure • His belief - cure comes from within the body itself rather than from an external chemical agent. • Difficulties -he had experienced in isolating and stabilizing penicillin, producing sufficient quantities for clinical trials- prevented him from realizing the full fruits of his research.

44. Fleming-After Penicillin • Fleming had turned his research to other chemical antibacterials, the sulphonamides • He kept producing and supplying his sample of penicillin to other labs and researchers for various studies and experiments. • For more than a decade or so no progress was made in the discovery of penicillin.

45. End of the 1st half

46. The 2nd half The discovery and realization of the chemotherapeutic potential of Penicillin

47. Sir Howard Walter Florey

48. Sir Howard Walter Florey • Born on September 24, 1898, at Adelaide, South Australia . • He graduated in M.B., B.S. in 1921from Adelaide University. • He was awarded a Rhodes Scholarship to Magdalene College, Oxford, leading to the degrees of B.Sc. and M.A. (1924).

49. Sir Howard Walter Florey • In 1925 he visited the United States on a Rockefeller Travelling Fellowship for a year, • Returned in 1926 to a Fellowship at Gonville and Caius College, Cambridge, received his Ph.D. in 1927. • In 1931 he succeeded to the Joseph Hunter Chair of Pathology at the University of Sheffield.

50. Sir Howard Walter Florey • Leaving Sheffield in 1935 he became Professor of Pathology and a Fellow of Lincoln College, Oxford. • 1936-He was made Director to the Sir William Dunn School of Pathology. • He was made an Honorary Fellow of Gonville and Caius College, Cambridge in 1946