Figure 7.

Farnesyltransferase activity is required to support hyphal morphogenesis in response to Nikkomycin Z. (A) Broth microdilution MIC analysis of the wild type (WT) and the ΔramA mutant. Ten thousand conidia from the wild type and 20 thousand conidia from the ΔramA mutant were inoculated into GMM liquid media with ascending doses of the specific chitin synthesis inhibitor, nikkomycin Z, and incubated for 48 hours at 37°C. 50% growth inhibition (MIC50) was noted for the ΔramA mutant at 1.6 µg/ml nikkomycin Z (dashed, red square) and complete growth inhibition at 50 µg/ml (solid, red square). Nikkomycin Z MIC of the wt was not achieved (> 100 µg/ml). (B) Microscopic examination of hyphae from the wild type (wt, left panel) and the ΔramA mutant (middle and right panels) grown for 24 hrs in GMM liquid media at 37°C in the presence of 1 µg/ml nikkomycin Z. Black arrowheads denote swollen hyphal segments in the ΔramA strain.