Resistance of Bacteria to the Penicillins. Ciba Foundation Study Group No. 13

This slender volume reports in lively form a 1962 Symposium concerned with the theoretical aspects of resistance of staphylococci to penicillin, and recent attempts to find new penicillins which would obviate this problem of resistance. Although it has been possible in the laboratory to render staphylococci penicillin-resistant without their producing penicillinase, nevertheless all naturally occurring penicillin-resistant strains of staphylococci are, without exception , penicillinase-producers. Small structural changes in the penicillin molecule might therefore be expected to alter markedly the affinity of the enzyme penicillinase for its substrate; recognition of this fact led several groups of organic chemists to systematically attempt to modify the benzyl penicillin (= penicillin G) molecule.