Dual mode of delivery of <i>Mycoplasma pneumoniae</i> CARDS toxin determines the toxin trafficking pathway and cytotoxicity in host cells.

ABSTRACT: Mycoplasma pneumoniae (Mp) causes both pulmonary and extrapulmonary infections in humans, and its virulence is largely attributed to the community-acquired respiratory distress syndrome (CARDS) toxin. CARDS toxin is transiently expressed during Mp growth in the serum-rich SP4 medium, detected predominantly in the cytoplasm, with none secreted into the medium. Here, we show that CARDS toxin synthesis has increased at least fivefold during Mp growth in serum-free minimal media, with approximately 40% of the toxin being released into the extracellular environment. In infected human alveolar epithelial cells, the toxin is visualized both in association with Mp and in free form around the perinuclear region, confirming its secretion. Using density gradient cen

SUBMITTER: Sreenath K 

PROVIDER: S-EPMC12802180 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature