FIG 3.

Effect of piliation on the growth of a recB mutant. (A) Growth of piliated versus nonpiliated parental and recB mutants. The titer of the parent FA1090 recA6 strain (Par) after 22 h of growth is compared to that of its recB::ermC derivative grown for 22 and 40 h. The solid bars indicate a completely piliated background (Avd-1), while the hatched bars indicate a completely nonpiliated background (ΔpilE). P+, piliated; P−, nonpiliated. (B) Colony appearance of the parental background strain (left) and the recB::ermC mutant (right) grown in the presence of IPTG for the indicated times. Top row, piliated Avd-1 background; middle row, nonpiliated ΔpilE background; bottom row, pilin Av-proficient background. The arrows point to emerging nonpiliated blebs.