Percentage of biotinylated flagellar protein bands recovered in flagellar vesicle fractions after 6 hr incubation.

Densitometric analysis of biotinylated bands in detergent extracts (membrane+matrix) of purified flagella and released flagellar vesicles. Biotinylated cells were incubated for 6 hrs. Cells were pelleted, deflagellated, and flagella were purified and extracted with NP-40. Vesicles were purified from the culture medium. Membrane+matrix and vesicle polypeptides were fractionated by SDS page and biotinylated proteins were stained on western blots. The densities of eight bands (Fig. S3) were measured and the proportion of polypeptides in the vesicle fraction compared to that in each membrane+matrix was determined based on the percentage of the sample loaded on the gels. Measurements from 5 different experiments and the average recovered protein for each of the bands are shown. The amount of FV protein recovered varied with different bands. A value of 100% indicates that the FV contains 100% of the biotinylated protein present in each flagellum. During the incubation, flagella maintain their quantities of biotinylated protein by drawing on the plasma membrane pool (see Fig. 3A).