Functional identification of A. pisum glucose and fructose transporters. Saccharomyces cerevisiae hexose transport mutant EBY.VW4000 was transformed with A. pisum gut expressed sugar transporters ApST1, ApST4 and ApST9. Positive control cells (+) were transformed with ApST3  and negative control (−) cells were transformed with empty expression vector. Yeast cell suspensions containing 10 μl of 1, 1/5 and 1/25 OD600 units were plated on minimal media containing 60 mM sugars (as indicated) as the sole carbon source. Recovery of mutant yeast growth was observed after 3-days at 30°C.