Comparison of the membrane interaction mechanism of two antimicrobial RNases: RNase 3/ECP and RNase 7.

摘要: Eosinophil cationic protein (ECP/RNase 3) and the skin derived ribonuclease 7 (RNase 7) are members of RNase A superfamily. 3 is mainly expressed in eosinophils whereas primarily secreted by keratinocytes. Both proteins present a broad-spectrum antimicrobial activity their bactericidal mechanism dependent on membrane destabilizing capacities. Using phospholipid vesicles as models, we have characterized association process. Confocal microscopy experiments using giant unilamellar illustrate morphological changes liposome population. By labelling both lipid bilayers monitored kinetic The differential ability to release aqueous content was evaluated together with micellation aggregation processes. distinct morphology protein/lipid aggregates visualized transmission electron overall secondary structure microenvironment assessed FTIR. Interestingly, for RNases interaction events take place different behaviour timing: triggers first vesicle aggregation, while induces leakage well before step. Their action at level may reflect vivo antipathogen functions.