Low Levels of Amino Acid Auxotrophy Among Environmental Pseudomonas Isolates.

Less than 2% of 315 environmental Pseudomonas isolates are amino acid auxotrophs, indicating they are predominantly prototrophs in pond and soil habitats.

• Why it matters: Understanding auxotrophy in environmental bacteria is crucial for ecological and metabolic modeling, but previous studies often rely on limited strains or bioinformatics alone, which can be biased.
• What they did: Researchers combined experimental growth tests with three bioinformatic pipelines to assess amino acid auxotrophies and their genetic bases across 315 Pseudomonas strains from natural habitats.
• The result: Findings show most Pseudomonas are prototrophic, with only a few auxotrophies and complex dependencies, suggesting a generalist lifestyle that challenges ecological predictions based solely on habitat or lifestyle.