A working understanding of parasite biochemistry has both general scientific interest and applications in drug or vaccine discovery. A parasitic mode of life causes adaptation in several aspects of biochemistry, including in the pathways of energy metabolism.
Unique metabolites suggest the expression of novel pathways for their synthesis.
Metabolic pathways in parasites are not completely understood because, to date, there have been many technical difficulties working with these organisms i.e. their location in a host animal, their different life cycles and environments, their physical size, and because they are often obtained in limited numbers. For example, the normal physiology of the parasite would likely be disrupted in in vitro culture following removal from the host and, in contrast, it is difficult to interpret data from in vivo studies. Furthermore, a small physical size coupled with limited numbers means that it is difficult to isolate and study specific tissues. Whole-parasite biochemistry using somatic extracts will clearly obscure the presence, absence or high activity of particular enzymes or pathways in some tissues. Parasites, as other organisms, need to have a supply of energy for synthesis of macromolecules and mechanical activity.