1. Objec&ve 1. Discuss the general history of
an&bio&cs (chemotherapy)
a) Who were some of the scien&sts who made
the earliest contribu&ons to an&bio&c
therapy?
b) What did they discover?
c) What were the two earliest an&bio&cs used?
d) What genus of bacteria produces the
majority of an&bio&cs?

2. First Medical Applica&on of an
An&bio&c
• Prontosil
• A chemical, product of the garment industry for
fabric dyes, 1908
• Domagk tested compounds from a red dye on
preven&ng mortality in mice infected with strep
or staph bacteria, 1930’s, Prontosil
• Commercially available 1935
• Used in WWII, but sulfa‐resistant strains
emerged
hQp://www.silentwall.com/Prontosil.html

3. • Awarded the prize 1939
• Prevented by the Nazi party from
accep&ng un&l 1947

4. Discovery of An&bio&cs
• Penicillium chrysogenum or notatum, only
certain strains
• Alexander Fleming, 1928
– Growing S. aureus in petri dishes
– Le plates out over a weekend, contaminated
with fungal growth
– Observed there was a clearing around the fungal
growth
– Fungus inhibited bacterial growth
– Research fizzled…forgoQen results

5. Applica&on of Penicillin
• Before widespread availability, home prepara&ons of fungus‐
soaked gauze for wounds – 3,000 years tradi&on
– Not always effec&ve, penicillin is strain‐dependent
• Florey, Abraham, Chain and Heatley rediscovered Fleming’s
paper
– Found the most effec&ve strain of P. chrysogenum that
came from a moldy cantaloupe (brought in by Mary Hunt,
“Mouldy Mary”)
• Raper, Moyer and Coghill
– Added corn steep liquor to increase produc&on of
penicillin – mass produc&on became possible
• 1940’s, WWII – effec&ve use to prevent amputa&on and many
deaths

7. Dirt!
• The majority of commercially available
an&bio&cs come from the genus of bacteria,
Streptomyces
• Streptomyces are filamentous bacteria found
in the soil (and are the component of dirt that
smell like “dirt”)
– An&bio&cs are secondary metabolites
– Nonessen&al chemicals derived from primary
metabolites
– Chemicals toxic to compe&ng species
– “bacteria are social”