Probing surface hydrophobicity of individual protein at single-molecule resolution using solid-state nanopores

Abstract

Solid-state nanopore is found to be a promising tool to detect proteins and their complexes. Nanopore-protein interaction is a fundamental and ubiquitous process in biology and medical biotechnology. By translocating phi29 connector protein through silicon nitride nanopores, we demonstrate preliminarily probing the surface hydrophobicity of individual protein at single-molecule resolution. The unique "double-level event" observed in the translocation and the ratio of two current drop levels suggest that the position where the interaction occurs is the hydrophobic surface of the protein. We provide a potential method to locate the hydrophobic region of a specific protein surface. This study is of fundamental significance in revealing the important role that hydrophobic interaction plays in nanopore-protein interaction and holds great potential for detecting local surface chemical property of individual protein using solid-state nanopores.

Coarse-grained molecular dynamics study of wettability influence on protein translocation through solid nanopores

“…The role of pore-water/protein interaction strength has been studied less till now. The nanopore-protein interaction is complicated, which involves several influencing factors, such as electrostatic force and van der Waals force, etc [23,24]. The corona formation theory can be used to describe the interaction between protein and nanopore based on the protein dwell time in experimental study [1].…”

Detection of a single enzyme molecule based on a solid-state nanopore sensor

“…Currently, silicon nitride (Si 3 N 4 ) nanopores have been proven to be a novel protein sensing platform with excellent physical and chemical stabilities. Many protein molecules have been studied by using solidstate nanopores including lysozyme [44], avidin [44], immunoglobulin G [44], β-lactoglobulin [44], ovalbumin [50], bovine serum albumin [24,39,44,51], β-galactosidase [50], his-tagged proteins [52], mammalian prion protein [44], phi29 connector protein [53], and histidine-containing phosphocarrier protein [50]. Besides, the Meller group has demonstrated that ubiquitin and ubiquitin chains can be efficiently discriminated using Si 3 N 4 nanopores [23].…”