Competition Sensing Changes Antibiotic Production in Streptomyces

Area of Science:

• Microbiology
• Bacterial Competition
• Antibiotic Production

Background:

• Bacteria produce antibiotics to compete for resources and space.
• Antibiotic synthesis is regulated by gene clusters and induced by specific cues from competitors.
• The precise cues and conditions triggering antibiotic production remain incompletely understood.

Purpose of the Study:

• To investigate the role of social cues and resource availability in regulating antibiotic production during bacterial competition.
• To determine how relatedness and shared biosynthetic pathways influence antibiotic induction.
• To examine the impact of competitor-induced growth inhibition and resource limitation on antibiotic output.

Main Methods:

• Studied interactions between 24 antibiotic-producing Streptomyces strains.
• Assessed growth inhibition and antibiotic production in response to different competitors.
• Varied nutrient availability to simulate resource limitation.

Main Results:

• Strains commonly inhibit each other's growth, more so if closely related.
• Antibiotic production is induced by cues from related strains or those sharing secondary metabolite biosynthetic gene clusters (BGCs).
• Competitors that inhibit growth do not generally induce antibiotic production; antibiotic output often decreases under resource limitation.

Conclusions:

• Social cues, particularly relatedness and shared BGCs, are critical for inducing antibiotic production in Streptomyces.
• Competitor-induced cell damage is not a general cue for antibiotic induction.
• Resource availability significantly modulates antibiotic production dynamics during bacterial competition, highlighting the interplay between social and resource environments.