Yeast cells cultured in shake-flasks at 30°C in 2×CBS medium supplemented with 2% glucose (A) were compared with those where the growth medium also contained 10 mM L-carnosine (B). Cells were visualized by light microscopy after reaching stationary phase, 48 h post inoculation. A proportion of the L-carnosine-treated cells (indicated with a white arrow; B) appear larger and more irregular in shape than control cells. The bar is 10 µM in length.