Direct Sensing and Discrimination among Ubiquitin and Ubiquitin Chains Using Solid-State Nanopores.

ABSTRACT: Nanopore sensing involves an electrophoretic transport of analytes through a nanoscale pore, permitting label-free sensing at the single-molecule level. However, to date, the detection of individual small proteins has been challenging, primarily due to the poor signal/noise ratio that these molecules produce during passage through the pore. Here, we show that fine adjustment of the buffer pH, close to the isoelectric point, can be used to slow down the translocation speed of the analytes, hence permitting sensing and characterization of small globular proteins. Ubiquitin (Ub) is a small protein of 8.5 kDa, which is well conserved in all eukaryotes. Ub conjugates to proteins as a posttranslational modification called ubiquitination. The immense diversity of Ub substrates, as well as the com

SUBMITTER: Nir I 

PROVIDER: S-EPMC4423055 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature