Global control of development and antibiotic production by nutrient-responsive signalling pathways in Streptomyces

Abstract

The soil is a thriving ecosystem, composed of both living and non-living matter with a multitude of interactions between them. It is considered as the most diverse microbial habitat on earth. Soil microorganisms perform important functions in recycling nutrients. They act as nutrient scavengers, obtaining nutrition from dead, decaying matter of plants and animals. Actinomycetes (including Streptomyces) are a large group of filamentous bacteria and may account even 30% of the total microorganisms in the soil rhizosphere, depending on nutrient availability (Barreto et al., 2008; Kennedy, 1999).They are able to utilize broad range of naturally occurring polymers, including starch, cellulose, chitin and xylan. A sufficiency of utilisable organic material promotes the vegetative growth of these bacteria, thereby delaying morphological development and associated antibiotic production. My thesis focuses on understanding the molecular mechanisms by which Streptomyces link nutrient availability with antibiotic production and development.