TLR4 and infection: Drosophila Toll pathway mutants were found to be more susceptible to infection by B. bassiana and M. anisopliae (entomopathogenic fungi) or by the opportunistic pathogen Aspergillus fumigatus compared to wild type flies (Lemaitre et al., 1997; Rutschmann et al., 2000; Tauszig-Delamasure et al., 2002).