FIG. 4.

Growth of WB800 and WB800BIO in a semidefined medium. WB800 and WB800BIO were cultured in CA medium containing vitamin-free Casamino Acids (see Materials and Methods for composition of CA medium). □, WB800 with no biotin added to the medium; □, WB800 with 40 μM biotin included in the medium; ▪, WB800BIO with no biotin and no sodium gluconate included in the medium; •, WB800BIO with no biotin but 0.2% sodium gluconate included in the medium. Three independent runs of these cell cultures were carried out and the standard deviation for each growth curve was within the 10% range.