Tiffany Zarrella (@tiffzarrella.bsky.social)

The Pel polysaccharide modulates interspecies interactions between Pseudomonas aeruginosa and Mycobacterium abscessus | mSystems Advances in treatments for cystic fibrosis have increased the incidence of “non-typical” infections, including those caused by non-tuberculous mycobacteria (NTM). NTM are often found in the lungs alongside the pathogen Pseudomonas aeruginosa, and patients infected with both tend to have worse clinical outcomes. In this study, we examined how these two organisms interact under biofilm conditions, an important lifestyle adaptation in chronic pulmonary infections. We found that when grown together, Mycobacterium abscessus enhanced biofilm formation by P. aeruginosa and reduced the effectiveness of antibiotic treatment. Our findings reveal a Pel-dependent interaction between two important lung pathogens that may contribute to more severe infections and poorer treatment outcomes in people with cystic fibrosis or other chronic lung diseases. Understanding these mechanisms opens new opportunities for developing strategies to combat these complex infections. https://journals.asm.org/doi/10.1128/msystems.00270-26