Prokaryotic protein-serine/threonine phosphatases.

Abstract

As this chapter deals with the protein-serine/threonine phosphatases of prokaryotic organisms, some comments on the role of prokaryotes in the study of these important enzymes would appear to be in order. Prokaryotic organisms dominate the living world. They represent by the largest source of biomass on the planet, forming the indispensable foundation of the food chain upon which all other living organisms depend. They are the exclusive agents for carrying out biological nitrogen fixation, and are responsible for the majority of the photosynthetic activity that generates the oxygen we breath. In absolute numbers, in number of species, in range of habitat, and in the spectrum of their metabolic activities, the prokaryotes far outpace their eukaryotic brethren. More immediately, in humans prokaryotes perform essential functions in the digestion and assimilation of nutrients, whereas infection by bacterial pathogens can lead to illness or death.