Apolipoprotein A-I plays a central role in the solution structure of high-density lipoproteins. Determining the stoichiometry of lipid-bound apo A-I in the hydrated state is therefore fundamental to understanding how high-density lipoproteins form and function. Here, we use the quantum optical phenomenon of photon antibunching to determine the number of apo A-I molecules bound to discoidal lipoproteins and compare this with values obtained by photon-counting histogram analysis. Both the photon antibunching and photon-counting analyses show that reconstituted high-density lipoprotein particles contain two apo A-I molecules, which is in agreement with the commonly accepted double-belt model. © 2011 Biophysical Society.
Ly, S., Petrlova, J., Huser, T., Fore, S., Gao, T., Voss, J., & Laurence, T. A. (2011). Stoichiometry of reconstituted high-density lipoproteins in the hydrated state determined by photon antibunching. Biophysical Journal, 101(4), 970–975. https://doi.org/10.1016/j.bpj.2011.06.060