Genome Sequences of Two Pseudomonas Isolates That Can Use Metformin as the Sole Nitrogen Source

Area of Science:

• Environmental microbiology
• Genomics
• Bioremediation

Background:

• Metformin is a widely used pharmaceutical and a significant emerging water pollutant.
• Conventional wastewater treatment methods are often ineffective at removing metformin.
• Microbial degradation offers a promising avenue for addressing metformin pollution.

Purpose of the Study:

• To identify and characterize microorganisms capable of utilizing metformin as a sole nitrogen source.
• To determine the genomic basis for metformin degradation in isolated bacterial strains.
• To investigate the potential role of plasmids in metformin biodegradation.

Main Methods:

• Isolation and cultivation of bacteria from wastewater treatment plant sludge using metformin as a nitrogen source.
• Whole-genome sequencing of promising bacterial isolates (Pseudomonas sp. strain KHPS1 and Pseudomonas hydrolytica strain KHPS2).
• Bioinformatic analysis to identify genes potentially involved in metformin metabolism and breakdown.

Main Results:

• Two bacterial strains, Pseudomonas sp. strain KHPS1 and P. hydrolytica strain KHPS2, were successfully isolated and identified.
• Both strains demonstrated the ability to grow using metformin as the sole nitrogen source.
• Genome sequencing revealed the presence of large plasmids (~80 kb) in both isolates, which are hypothesized to harbor metformin degradation genes.

Conclusions:

• Pseudomonas sp. strain KHPS1 and P. hydrolytica strain KHPS2 are novel metformin-degrading bacteria.
• The identified plasmids represent a potential genetic resource for understanding and engineering metformin biodegradation pathways.
• These findings contribute to the development of bioremediation strategies for pharmaceutical pollutants in aquatic environments.