FIG. 3.

Immunogold labeling of CY028 and CY181 cutinase-producing S. cerevisiae strains. S. cerevisiae cells were cryofixed and freeze-substituted as described in Materials and Methods. (A and B) CY028 cutinase-producing cells were labeled with anticutinase and goat antirabbit antibodies conjugated with 6-nm-diameter-gold particles. (C and D) CY181 cutinase-producing cells were labeled with anti-cutinase and goat antirabbit antibodies conjugated with 6-nm-diameter-gold particles. CY028 cutinase is located in large electron-dense structures (A and B), whereas CY181 cutinase is distributed homogenously around the nucleus and in structures most likely representing the ER (C and D). Bars represent 500 nm in panels A and C and 100 nm in panels B and D. Arrowheads indicate CY028 cutinase aggregates. Abbreviations: Pm, plasma membrane; Ne, nuclear envelope; cw, cell wall; Nu, nucleus; Vac, vacuole.