Schematic summarizing the known effects of BPI's binding to the outer membrane of GNB. ActD is a hydrophobic antibiotic that is impermeable to the LPS barrier of the bacterial membrane. Upon treatment with BPI, GNB become susceptible to ActD, implying significant disruption of the protective LPS barrier. Other effects of BPI binding include activation of endogenous phospholipases that contribute to the degradation of the outer membrane.