Three new polyketides, phaeochromycins F (1), G (2), H (3), were obtained from the culture broth of marine actinomycete strain Streptomyces sp. DSS-18. Their structures were established on the basis of detailed spectroscopic analyses, including 1D-, 2D-NMR and HR-ESI MS techniques.

1. Abstract 2. Introduction 3. Actinomycetes 4. Antibiotic discovery-The odyssey begins 5. The early years 6. The golden period of antibiotics 7. Significant actinomycete antibioticspast to present 7.1 Streptomycin 7.2 Tetracyclines 7.3 Chloramphenicol 7.4 Neomycin 7.5 Erythromycin 7.6 Vancomycin 7.7 Kanamycin 7.8 Rifamycin 7.9 Gentamicin 7.10 Daptomycin 8. Recent advances 8.1 Platensimycin 8.2...

We report methods to generate protoplasts, to regenerate mycelia, and to transform Micromonospora echinospora. This actinomycete produces the unusual antitumor antibiotics, the calicheamicins. These protocols may be applied to other actinomycetes that have been difficult to transform. These methods also may facilitate the cloning of calicheamicin biosynthetic genes by genetic complementation.

Many bacteria, particularly actinomycetes, are known to produce secondary metabolites synthesized by polyketide synthases (PKS). Bacterial polyketides are a particularly rich source of bioactive molecules, many of which are of potential pharmaceutical relevance. To directly access PKS gene diversity from soil, we developed degenerate PCR primers for actinomycete type II KS(alpha) (ketosynthase)...