Investigating the Effects of Antibiotics on E-coli
The antibiotic that was the most effective was Streptomycin. This was due to Streptomycin being an antibiotic that works on gram negative bacteria. Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol whereas Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. The bacteria we used were E-coli that are a gram negative bacteria and the only antibiotic out of Penicillin and Streptomycin that will work is Streptomycin. Penicillin is also effective antibiotic but it will only work on bacteria that Is gram positive because it is an antibiotic that has been designed in order to just work on gram positive because the antibiotic itself is gram positive. We know that Streptomycin was most effect due to their being a bigger zone of inhibition. Streptomycin was also the most effective because it affects the protein synthesis whereas Penicillin affects bacterial cell wall synthesis. Penicillin lengthens the bacteria but it cannot divide it.
We didn’t encounter that many difficulties during this practical but if we had to name one it would probably be flaming everything we used we had to make sure we did it very safely.
Unfortunately our aseptic techniques was not successful even though we tried to carry out all the techniques unfortunately some of the points were not successful. This could have been due to me and partner not carrying the whole experiment in a sterile environment e.g. near the Bunsen burner or it could have been to due exposing the whole petri dish when we are spreading on the bacteria on the agar plate other bacteria that was around could have caught on.
Streptomycin is an antibiotic used to kill sensitive bacteria. It is an aminoglycoside which works by stopping the production of essential proteins. Streptomycin is a powerful antibiotic that inhibits growth of