Interactions between Mycoplasma pulmonis and immune systems in the mealworm beetle, Tenebrio molitor.

Mycoplasmas, the smallest self-replicating organisms, are unique in that they lack cell walls but possess distinctive plasma membranes containing sterol acquired from their growth environment. Although mycoplasmas are known to be successful pathogens in a wide range of animal hosts, including humans, the molecular basis for their virulence and interaction with the host immune systems remains largely unknown. This study was conducted to elucidate the biochemical relationship between mycoplasma and the insect immune system.

Interaction of cationic antimicrobial peptides with Mycoplasma pulmonis.

We investigated the mode of action underlying the anti-mycoplasma activity of cationic antimicrobial peptides (AMPs) using four known AMPs and Mycoplasma pulmonis as a model mycoplasma. Scanning electron microscopy revealed that the integrity of the M. pulmonis membrane was significantly damaged within 30 min of AMPs exposure, which was confirmed by measuring the uptake of propidium iodine into the mycoplasma cells.