Dissection of functional domains of the polar localization factor PodJ in Caulobacter crescentus.
The polar organelle development protein, PodJ, is important for proper establishment of polarity in Caulobacter crescentus. podJ null mutants are unable to form holdfast or pili, have reduced swarming motility, and have difficulty ejecting the flagellum during the swarmer to stalked cell transition. In this study, we create a series of truncation mutants to investigate functional domains of PodJ. We show that PodJ has a transmembrane domain between amino acids 600 and 670. We identify a periplasmic region important for pili production and a cytoplasmic region required for holdfast formation and swarming motility, and establish that PleC localization is not required for holdfast formation and motility in soft agar. Analysis of the mutants reveals that the last 54 amino acids of the protein negatively regulate processing of the full-length form of the protein, PodJ(L), to a shorter form, PodJ(S). Finally, we identify a cytoplasmic region of PodJ involved in targeting it to the flagellar pole, and a periplasmic region required for localization of PleC.
Lawler
Melanie L
ML
Department of Biology, Indiana University, 1001 E. Third Street, Bloomington, IN 47405-7005, USA.
Larson
David E
DE
Hinz
Aaron J
AJ
Klein
David
D
Brun
Yves V
YV
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016935:Caulobacter crescentus / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D002465:Cell Movement / Q000502:physiology; D016764:Cell Polarity; D036781:Fimbriae Proteins / Q000235:genetics / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D010641:Phenotype; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; C120058:podj protein, Caulobacter crescentus; D036781:Fimbriae Proteins