Penicillin Essay
Penicillin Essay (25marks)
Considered to be the first of the antibiotic medicines, and the first important commercial product to be produced by an aerobic, submerged fermentation, penicillin (as originally coined) strictly refers to the antimicrobial agent produced naturally by the microbe Penicilium notatum; a form of filamentous fungus.
Originally discovered by Ernest Duschesne in 1896, it was later ‘rediscovered’ by Alexander Flemming in 1928, who was then credited for the discovery – though there remains much debate as to whether Flemming deserves said credit. This is due to the fact that while he may have noticed penicillin, Flemming believed that it’s potential uses lay in acting as a laboratory agent (as stated in his 1929 paper on the antibacterial actions of cultures of Penicilium, with special reference to their use in the isolation of b-influenza); he did not create penicillin as a therapeutic agent (as a medicine), and, according to this paper, was not interested in any potential penicillin might have had within the human body – as Florey and Chain (who isolated penicillin for human use) were.
Penicillin works as a therapeutic agent by destroys bacteria (bacteriocidal): it inhibits cell wall biosynthesis (by disrupting the normal balance between cell wall biosynthesis and degradation), specifically binding to and inactivating enzymes that function to form the cross-linkages of peptidoglycan strands in bacterial cell walls (weakening said cell walls). Since cell wall expansion also requires the action of enzymes that degrade cell walls, exposure of growing bacteria to penicillin results in their lysis.
Though penicillin is affective against a large number of bacteria, which would indicate it being a broad spectrum antibiotic (activity against a wide range of disease-causing bacteria), it is yet considered a narrow spectrum antibiotic due to the fact that it has little effect on gram-negative bacteria – working instead on gram-positive bacteria.
Considered to be the first of the antibiotic medicines, and the first important commercial product to be produced by an aerobic, submerged fermentation, penicillin (as originally coined) strictly refers to the antimicrobial agent produced naturally by the microbe Penicilium notatum; a form of filamentous fungus.
Originally discovered by Ernest Duschesne in 1896, it was later ‘rediscovered’ by Alexander Flemming in 1928, who was then credited for the discovery – though there remains much debate as to whether Flemming deserves said credit. This is due to the fact that while he may have noticed penicillin, Flemming believed that it’s potential uses lay in acting as a laboratory agent (as stated in his 1929 paper on the antibacterial actions of cultures of Penicilium, with special reference to their use in the isolation of b-influenza); he did not create penicillin as a therapeutic agent (as a medicine), and, according to this paper, was not interested in any potential penicillin might have had within the human body – as Florey and Chain (who isolated penicillin for human use) were.
Penicillin works as a therapeutic agent by destroys bacteria (bacteriocidal): it inhibits cell wall biosynthesis (by disrupting the normal balance between cell wall biosynthesis and degradation), specifically binding to and inactivating enzymes that function to form the cross-linkages of peptidoglycan strands in bacterial cell walls (weakening said cell walls). Since cell wall expansion also requires the action of enzymes that degrade cell walls, exposure of growing bacteria to penicillin results in their lysis.
Though penicillin is affective against a large number of bacteria, which would indicate it being a broad spectrum antibiotic (activity against a wide range of disease-causing bacteria), it is yet considered a narrow spectrum antibiotic due to the fact that it has little effect on gram-negative bacteria – working instead on gram-positive bacteria.