TY - JOUR
T1 - Engineering a rigid protein tunnel for biomolecular detection
AU - Mohammad, Mohammad M.
AU - Iyer, Raghuvaran
AU - Howard, Khalil R.
AU - McPike, Mark P.
AU - Borer, Philip N.
AU - Movileanu, Liviu
PY - 2012/6/6
Y1 - 2012/6/6
N2 - One intimidating challenge in protein nanopore-based technologies is designing robust protein scaffolds that remain functionally intact under a broad spectrum of detection conditions. Here, we show that an extensively engineered bacterial ferric hydroxamate uptake component A (FhuA), a β-barrel membrane protein, functions as a robust protein tunnel for the sampling of biomolecular events. The key implementation in this work was the coupling of direct genetic engineering with a refolding approach to produce an unusually stable protein nanopore. More importantly, this nanostructure maintained its stability under many experimental circumstances, some of which, including low ion concentration and highly acidic aqueous phase, are normally employed to gate, destabilize, or unfold β-barrel membrane proteins. To demonstrate these advantageous traits, we show that the engineered FhuA-based protein nanopore functioned as a sensing element for examining the proteolytic activity of an enzyme at highly acidic pH and for determining the kinetics of protein-DNA aptamer interactions at physiological salt concentration.
AB - One intimidating challenge in protein nanopore-based technologies is designing robust protein scaffolds that remain functionally intact under a broad spectrum of detection conditions. Here, we show that an extensively engineered bacterial ferric hydroxamate uptake component A (FhuA), a β-barrel membrane protein, functions as a robust protein tunnel for the sampling of biomolecular events. The key implementation in this work was the coupling of direct genetic engineering with a refolding approach to produce an unusually stable protein nanopore. More importantly, this nanostructure maintained its stability under many experimental circumstances, some of which, including low ion concentration and highly acidic aqueous phase, are normally employed to gate, destabilize, or unfold β-barrel membrane proteins. To demonstrate these advantageous traits, we show that the engineered FhuA-based protein nanopore functioned as a sensing element for examining the proteolytic activity of an enzyme at highly acidic pH and for determining the kinetics of protein-DNA aptamer interactions at physiological salt concentration.
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U2 - 10.1021/ja3043646
DO - 10.1021/ja3043646
M3 - Article
C2 - 22577864
AN - SCOPUS:84861848823
SN - 0002-7863
VL - 134
SP - 9521
EP - 9531
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 22
ER -