Figure 4: Construction of the yeast strain secreting PvPGIPs
and establishment of fungal growth inhibition assay. (a)Western blot analysis of S. cerevisiae engineered to secret
PvPGIP1 with anti-HA antibody after three days of growth. PvPGIP1-HA has
an expected size at 43kDa. The cell lysate samples indicate the presence
of the protein inside the cell. The medium samples indicate the presence
of the secreted protein into the yeast medium. The inhibition activity
of the secreted PvPGIPs was then tested on a fungal growth inhibition
assay. OD readings at 630nm of (b) A. niger and(C) B. cinerea treated with either natamycin (positive
control), empty vector yeast (negative control), tPvPGIP2_5-8 secreting
yeast, or PvPGIP2 secreting yeast were taken after four days. At 630nm,
OD readings are reported to be proportional to the dry weight of fungi
(Langvad, 1999). Each bar represents the mean values of six biological
replicates, and the err or bars represent the standard deviation of the
replicates. The well pictured above each bar is representative sample of
the replicates.