Mutants Blocked in Antibiotic Synthesis

INTRODUCTION ... . ........ 594 MUTANTS BLOCKED IN PRIMARY AND SECONDARY METABOLISM: A GENERAL COMPARISON OF AUXOTROPHS AND ANTIBIOTIC-BLOCKED MUTANTS 595 Classification of Mutants... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595 Mutant Selection 596 Accumulation of Metabolites in Blocked Mutants 597 Identification of Accumulated Metabolites as Intermediates 598 MOLECULAR INTERPRETATION OF ANTIBIOTIC-BLOCKED MUTANTS: SPECIFIC EXAMPLES 598 Peptide Antibiotics . . . ....... . . . . . . .. ....... . . . . . . . . ....... . ... ......... . ..... .... . . . . . . . . . ... . ... . . . . . ... . ... .. ..... . . . . 598 Cephalosporins 599 Penicillins 602 Gramicidin S ...... 604 Deslruxins . . . . . . . . ..... ... . . ... ... . . ... . . . . . . . ... ... . ... . . . ... ... ... ... . ... ... ... . ... . ... ... ... ... . . . . . ......... . . . .. . ... . 605 Aminocyclitol Antibiotics .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 606 Mutatjonal biosynthesis (mutasynthesis) 607 Neomycin B .. , ......... ..... ...... ......... 607 Streptomycin 608