Lateral organization of proteins and lipids in the plasma membrane and the kinetics and lipid-dependence of lysine transport in Saccharomyces cerevisiae

During his promotion, Joury van ‘t Klooster studied the kinetics of lysine transport and the lateral organization of proteins and lipids in the plasma membrane of yeast.

The plasma membrane of yeast is very robust. This is believed to be caused by the ordered positioning of the lipids that make up the plasma membrane. The ordered structure results in low solute permeation and slow lateral diffusion of proteins compared to other cells such as mammalian and bacterial cells. However, how membrane proteins are able to function in an environment of such high order is unknown.

His research is focused on the structure and functioning of membrane proteins and the role lipids play in this. With special interest in a lysine transporter. He was able to partly explain the uni-directional transport of lysine and identified regions of the transporter that are important for the localization and functioning. He furthermore combined existing methods and developed an assay to identify and quantify lipids closely associated with membrane proteins. With this he was able to show that the lipid profile surrounding membrane proteins is different than the profile of the entire plasma membrane. He further showed that the lysine transporter needs specific types of lipids to function properly and that these lipids resemble the lipid profile surrounding membrane proteins more closely than the profile of the entire plasma membrane. Finally, he proposes a model for the lateral organization of proteins and lipids in the plasma membrane of yeast.