Analysis of pore formation and protein translocation using large biological nanopores.

This paper describes the analysis of pore formation and detection of a single protein molecule using a large nanopore among five different pore-forming proteins. We demonstrate that the identification of appropriate pores for nanopore sensing can be achieved by classifying the channel current signals and performing noise analysis. Through these analyses, we selected a perforin nanopore from the membrane attack complex/perforin superfamily and attempted to use it to detect the granzyme B protein, a serine protease. As a result, we found that granzyme B might pass through the perforin nanopore if it adopts an unfolded structure. Our proposed analytical approach should be useful for exploring several types of nanopore as large biological nanopores other than α-hemolysin.