Streptomyces as symbionts: an emerging and widespread theme?

Area of Science:

• Microbiology and Symbiotic Interactions
• Natural Product Chemistry
• Ecology

Background:

• Streptomyces bacteria are common soil microorganisms known for their role in organic matter decomposition.
• Emerging research reveals Streptomyces also engage in symbiotic relationships with various organisms, including plants, fungi, and animals.
• The chemical diversity of secondary metabolites produced by Streptomyces is likely driven by these inter-species interactions.

Purpose of the Study:

• To review current knowledge on the symbiotic roles of Streptomyces with fungi, plants, and animals.
• To explore the ecological significance and evolutionary drivers of these symbiotic relationships.
• To highlight the potential of these interactions in the search for novel antibiotics.

Main Methods:

• Literature review of existing research on Streptomyces symbiosis.
• Analysis of documented parasitic and mutualistic interactions.
• Exploration of secondary metabolite production in symbiotic contexts.

Main Results:

• Streptomyces exhibit both parasitic (e.g., plant scab, human infections) and beneficial symbiotic interactions.
• Beneficial symbioses often involve the production of antibiotics by Streptomyces, which protect host organisms (insects, plants, marine animals) from infections.
• These symbiotic relationships contribute significantly to the chemical diversity of Streptomyces secondary metabolites.

Conclusions:

• Streptomyces are versatile symbionts with diverse ecological roles beyond soil decomposition.
• Symbiotic interactions are key drivers for the evolution of Streptomyces' secondary metabolite production.
• Investigating Streptomyces symbiosis in under-explored environments is a promising avenue for novel antibiotic discovery.