microbial-degradation
Microbial degradation is the process by which microorganisms break down organic compounds, including dead plant material and other substrates in soil. This is critical for plant science because it enables nutrient cycling, converting plant-derived organic matter into bioavailable forms that support plant growth and soil fertility. Understanding microbial degradation is essential for comprehending soil health and the dynamic interactions between plants and their soil microbial communities.
PubMed · 2026-06-12
Scientists discovered a bacterial protein that efficiently absorbs metformin — the world's most prescribed diabetes drug — allowing soil and water bacteria to break it down. This finding explains how microbes degrade a pharmaceutical that has become a widespread environmental pollutant in rivers, groundwater, and agricultural soils.
The discovered transporter (MetT) binds metformin with a Km of 15.90 µM — roughly 100-fold higher affinity than the human equivalent, meaning bacteria can scavenge metformin even at very low environmental concentrations.
Knocking out the metT gene completely stopped the bacterium from growing on metformin, proving the transporter is the essential gateway before any degradation can occur.
Structural modeling showed the binding pocket is lined with aromatic amino acids that grip metformin via cation-π interactions — a distinct recognition mechanism not seen in previously characterized transporters of this family.