Nutrient availability shapes the microbial community structure in sugarcane bagasse compost-derived consortia

Area of Science:

• Microbiology
• Environmental Science
• Biotechnology

Background:

• Microbial communities (MCs) form complex metabolic networks in nature.
• Environmental changes induce shifts in MC structure.
• Cultivating diverse MCs in the lab requires mimicking environmental conditions, often through mixed cultures.

Purpose of the Study:

• To test the hypothesis that nutrient-limited conditions support greater microbial diversity.
• To explore the structure of a compost-derived MC under varying nutrient availability.
• To identify selective pressures on microbial biodiversity.

Main Methods:

• Utilized a 16S rRNA amplicon metagenomic approach.
• Cultivated compost-derived MCs in minimal medium with sugarcane bagasse (SCB) as the sole carbon source.
• Compared microbial diversity and structure in nutrient-limited versus nutrient-rich conditions over a five-week period.

Main Results:

• Nutrient-limited medium with SCB enriched lignocellulose-degrading microorganisms and increased microbial diversity.
• Nutrient-rich medium with SCB resulted in lower microbial diversity and fewer lignocellulolytic species.
• Nutrient availability was identified as a significant selective pressure on MC biodiversity.

Conclusions:

• Nutrient-limited conditions favor the enrichment of specialized microorganisms, such as lignocellulose degraders.
• This approach can displace generalist bacterial species, creating an enriched source for novel enzyme discovery.
• Optimizing nutrient availability in lab-grown MCs is crucial for harnessing microbial diversity for biotechnological applications.