Streptomyces Volatile Compounds Influence Exploration and Microbial Community Dynamics by Altering Iron Availability

Area of Science:

• Microbiology
• Environmental Science
• Biochemistry

Background:

• Bacteria and fungi produce volatile organic compounds (VOCs) for chemical signaling and competition.
• Trimethylamine (TMA) is a VOC that promotes a unique growth pattern in Streptomyces called "exploration."
• The role of VOCs in natural microbial communities is an emerging area of research.

Purpose of the Study:

• To investigate how TMA influences nutrient availability and microbial interactions.
• To understand the mechanisms by which TMA affects Streptomyces growth and competition.
• To explore the role of iron availability in TMA-mediated Streptomyces exploration.

Main Methods:

• Analysis of volatile organic compounds (VOCs) produced by Streptomyces.
• Measurement of environmental pH and iron availability around exploring cultures.
• Gene expression analysis of siderophore synthesis and uptake in Streptomyces.
• Co-culture experiments with Streptomyces and other microbes (e.g., Amycolatopsis).

Main Results:

• TMA significantly increases environmental pH, leading to reduced iron availability.
• Low iron conditions inhibit the growth of competing soil bacteria and fungi.
• Streptomyces venezuelae upregulates siderophore production and uptake genes in response to low iron.
• Reduced iron availability and co-culturing with iron-competing bacteria enhance Streptomyces exploration.

Conclusions:

• TMA acts as a VOC that modulates iron availability, creating a competitive advantage for Streptomyces.
• Iron limitation is a key factor that promotes Streptomyces exploration.
• VOCs play a critical role in shaping microbial community structure and interspecies interactions.