Aberrantly Large Single-Channel Conductance of Polyhistidine Arm-Containing Protein Nanopores.

ABSTRACT: There have been only a few studies reporting on the impact of polyhistidine affinity tags on the structure, function, and dynamics of proteins. Because of the relatively short size of the tags, they are often thought to have little or no effect on the conformation or activity of a protein. Here, using membrane protein design and single-molecule electrophysiology, we determined that the presence of a hexahistidine arm at the N-terminus of a truncated FhuA-based protein nanopore, leaving the C-terminus untagged, produces an unusual increase in the unitary conductance to ∼8 nS in 1 M KCl. To the best of our knowledge, this is the largest single-channel conductance ever recorded with a monomeric β-barrel outer membrane protein. The hexahistidine arm was captured by an anti-polyhistidine tag mo

SUBMITTER: Thakur AK 

PROVIDER: S-EPMC5595664 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature