Fig. 2

PilZLe3639 and its residue W71 both played essential roles in the formation of twitching motility by L. enzymogenes. Mutation of pilZLe3639 in wild-type OH11 led to a complete defect in forming twitching motility, as no twitching cells (indicated by blight arrows) were observed at the margin of strain colony. Complementing the wild-type PilZLe3639 or a variant carrying a Y24-A24 substitution (indicated as Y24A) into the mutant both rescued this motile deficiency. Introducing the empty vector (pBBR1-MCS5, abbreviated as pBBR) or the pilZLe3639 variant possessing a W71-A71 replacement (indicated as W71A) failed to rescue the twitching deficiency of the pilZLe3639 mutant