A traditional nanodisc is composed of a nanometer-sized phospholipid bilayer patch encircled by two copies of membrane scaffold protein (MSP). To date, the utility of this system for structural studies has been limited by the heterogeneity in size and only small nanodiscs could be assembled with the currently available MSP. Here, we present novel nanodiscs encircled by DNA scaffold and covalently circularized MSP variants (cMSPs). The use of cMSPs enhanced the homogeneity, thermal stability and proteolytic resistance of the nanodiscs.

URL: https://www.cell.com/biophysj/abstract/S0006-3495(16)32679-0