The nitrogen regulatory protein C (NTRC) is a bacterial enhancer-binding protein (transcriptional activator) that contacts the RNA polymerase by DNA loop formation. The enhancer facilitates formation of an oligomer that is the active entity. (The protein is a dimer in solution). The goal was to determine the number of dimers of NTRC bound to a DNA template carrying a single site, a DNA template carrying two sites (an """"""""enhancer""""""""), and a two site (""""""""enhancer"""""""") DNA template when NTRC is phosphorylated. Unfortunately, the components of the reaction mix contained PEG, as well as glycerol (which usually washes off), and required BSA (which we, of course, left out). Consequently, most of the grids were opaque or coated and uninterpretable. The study awaits purification of STEM-compatible components. One interesting observation came from this: polylysine pre-treated grids seemed to bind PEG less well than carbon grids.
Showing the most recent 10 out of 101 publications
