초록 |
We characterized pseudin-2, an AMP isolated from the skin of the South American paradoxical frog Pseudis paradoxa. We found that pseudin-2 organized to an aggregated state in aqueous solution, but that it dissociated into monomers upon binding to lipopolysaccharide, even though it did not neutralize LPS in Gram-negative bacteria. In addition, pseudin-2 assumed an α-helical structure in the presence of biological membranes and formed pores in microbial membranes, through which it entered the cytoplasm and tightly bound to RNA. Thus, the potent antimicrobial activity of pseudin-2 likely results from both the formation of pores capable of collapsing the membrane potential and releasing intracellular materials and its inhibition of macromolecule synthesis through its binding to RNA. |