Figure 2. A fragment of multiple sequence alignment of CYP51 from different biological kingdoms in the region of P355 (T. cruzi numbering).
P355 is marked with black arrow. P/S variation is also found in CYP51A in several filamentous ascomycetes, whose constitutively expressed CYP51B paralogues always have P in this position. More extended alignment can be seen as Supplemental Figure 1.