“…In other cases, they involve subtle differences in the active site geometry of specific enzymes, and in yet others, they are the outcome of a completely different set of regulatory mechanisms. Thus, despite the underlying structural conservation, differences abound, the possibility of using GPIs and GPI biosynthetic steps as vaccines and drug targets in eukaryotic pathogens continues to generate much interest ( 3 , 4 , 5 , 6 , 7 ).…”