Classification of antibiotics

1. Anti bacterial
Antibiotics
HumanlivesVsMicroorganism
AntibioticsVsInfections

2. Antibiotics
• Antibiosis (literally “against life”) as the biological concept of
survival of the fittest, in which one organism destroys another to
preserve itself.
• In 1942, Waksman defined “an antibiotic or antibiotic substance is
a substance produced by microorganisms, which has the capacity
of inhibiting the growth and even of destroying other
microorganisms.”

3. Antibiotics
Therefore, a substance is classified as an antibiotic if the
following conditions are met:
1. It is a product of metabolism
2. It is a synthetic product produced as a structural analog of a naturally
occurring antibiotic.
3. It antagonizes the growth or survival of one or more species of
microorganisms.
4. It is effective in low concentrations.

4. Chemical Classification of Antibiotics
Sr Class , Subclass & action mechanism Examples
1 β- lactam & β lactamase inhibitors
1.a Penicillins &
Cephalosporins
Cell wall cross-linking
Amoxicillin & Ampicillin
1.b Cefuroxime, Cefotaxime,
1.c β lactamase inhibitors Inactivate/ inhibit β lactamase Clavulanates, Carbapenems
2 Aminoglycosides
30 S subunit Protein synthesis &
fidelity
Kanamycin, Gentamicin,
Tobramycin,
3 Tetracycline 30 S subunit Protein synthesis
Oxytetracycline,
Demeclocycline,
4 Macrolides 50 S subunit Protein synthesis
Erythromycin, Clarithromycin,
Azithromycin
5 Lincomycins 50 S subunit Protein synthesis Lincomycin, Clindamycin
6
Peptides/
Polypeptides
Cell wall synthesis & cell membrane
functions
Vancomycin, Bacitracin,
Polymyxin B
7 Chloramphenicol Ribosomes  Protein synthesis
8 Quinolones
Bacterial DNA gyrase
(Topoisomerase II)
Norfloxacin, Ciprofloxacin
9 Miscellaneous Varied Novobiocin, Linezolid
PC2ATMLinQ