Pleiotropic role of PAX cyclolipopeptides in the <i>Xenorhabdus</i> bacterium mutualistically associated with entomopathogenic nematodes.
Uncover the secret life of PAX cyclolipopeptides - these versatile molecules play a pivotal role in the intricate dance between Xenorhabdus bacteria and their nematode partners, shaping biofilm formation, motility, and nematode production.
This study delves into the multifaceted functions of PAX cyclolipopeptides in the Xenorhabdus bacterium, which maintains a mutualistic relationship with entomopathogenic Steinernema nematodes. Through mass spectrometry analysis, the researchers tracked the presence of PAX peptides throughout the Xenorhabdus life cycle, from the pathogenic to the necrotrophic stage. Notably, they discovered that the production of these NRP-type molecules is linked to the bacterium's distinctive bromothymol blue adsorption phenotype. Further investigations revealed that PAX peptides positively influence biofilm formation while negatively impacting swimming motility. Importantly, the team also found that PAX peptides promote the in vivo production of infective Steinernema juveniles, suggesting their crucial role in the Xenorhabdus-nematode partnership. This comprehensive study sheds light on the pleiotropic ecological functions of these specialized metabolites, which are conserved across the Xenorhabdus genus, with the