Vacuolar H+ pyrophosphatases:: from the evolutionary backwaters into the mainstream

Vacuolar-type H+-translocating inorganic pyrophosphatases have long been considered to be restricted to plants and to a few species of phototrophic bacteria. However, in recent investigations, these pyrophosphatases have been found in organisms as disparate as thermophilic Archaea and parasitic protists, and have resulted in the definition of a novel subclass in plants themselves. Among the many evolutionary and practical implications of these findings is the possibility that this research will spawn new approaches to the treatment of several prolific and debilitating parasite-mediated infections.