Figure 1. Lysine transport in Saccharomyces cerevisiae.

(a) Confocal imaging of Lyp1-YPet and Lyp1(62–590)-YPet expressing cells and grown in the presence and absence of lysine. (b) Lysine transport rate of wild-type Lyp1 and Lyp1(62-590) expressing cells grown in the presence and absence of lysine. (c,d) Effect of FCCP (circles) and 100 mM lysine (500x fold excess of unlabeled solute, triangles) on the uptake of lysine into cells overexpressing Lyp1(62-590)-YPet; time-point of addition is indicated by arrows. (c) In S. cerevisiae BY4742, the initial rates of export expressed (as mM lysine*min⁻¹ and SEM calculated) were 0.30 ± 0.02 and 0.28 ± 0.07 for FCCP treatment and lysine chase, respectively. (d) For S. cerevisiae BY4742 ∆vba1, ∆vba2, ∆Lys1, the respective values were 0.25 ± 0.02 and 0.36 ± 0.04 mM lysine*min⁻¹. The rates of efflux and SEM are based on biological replicates (n = 3), and the observed differences are not significant.