Energetic Metabolism of Streptomyces

Streptomyces belong to the Actinomycetales order. They are Gram + filamentous bacteria, living in the superficial layers of land or sea soils. These bacteria actively contribute to the fertility of these soils as well as to plants nutrition and health thanks to their ability to degrade a number of organic molecules of animal or vegetal origin and to produce molecules able to inhibit growth of phytopathogenic agents. In addition, these bacteria are responsible for the production of approximately 2/3 of the antibiotics in common use as well as that of many other bioactive molecules useful for human health (anti-cancer, anti-inflammatory, anti- obesity…) or agriculture (anti-fungals, pesticides, herbicides…). It has long been known that the production of most antibiotics usually takes place when growth slows down or stops because of nutritional limitations and that a limitation in phosphate is a major trigger of antibiotics biosynthesis. The coincidence of growth slow down, probably linked to an energetic deficit, and the production of antibiotics raises the question of the role of antibiotics for the producing bacteria in this specific context.