Fig. 4.

Additional fungal secondary metabolites known to inhibit SL metabolism and/or with close structural similarity to known substrates/inhibitors. The sphingoid base-like structural features of AAL toxin TA1 and AOD are colored blue with additional functional groups in red and green, as in Fig. 1. Australifungin shares some of these features (as an alkyl polyol), but lacks the characteristic amino-group of sphingoid bases. There are also several fungal metabolites, such as myriocin (not shown), that are potent inhibitors of SPT. References for these compounds are given in the text.