Kinetic analysis of the interaction between PAB-TP and the membranes containing 10 mol% of PA showed that PAB-TP associated with PA with a low dissociation constant of K D = 38 ± 5 nM. Coexistence of cholesterol or PE with PA in the membrane enhanced the PAB-TP binding to PA by increasing the ionization of the phosphomonoester head group as well as by changing the microenvironment of PA molecules in the membrane.
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