Under normal conditions, most B. thuringiensis protoxin proteins are synthesized only during the sporulation phase of growth. In other words, only a portion of the growth cycle of the organism is devoted to parasporal crystal production. It might therefore be advantageous, in terms of increased yield and decreased production time, to have the toxin gene transcribed and translated during vegetative growth. Furthermore, production of the insecticidal toxin during vegetative growth would permit the toxin to be synthesized by a continuous fermentation process, potentially significantly decreasing the cost of producing it. Continuous fermentations are carried out with smaller-scale—and therefore less expensive—bioreactors and downstream processing equipment than conventional batch fermentations. (See chapter 17 for additional details.)