title: Role of polyadenylation in regulation of the flagella cascade and motility in Escherichia coli.
abstract: Polyadenylation is recognized as part of a surveillance machinery for eliminating defective RNA molecules in eukaryotes and prokaryotes. Escherichia coli strains, deficient in poly(A)polymerase I (PAP I), expressed less flagellin compared to wild-type strains. Because flagellin synthesis is a late step in the flagellar biosynthesis pathway, we assessed the role of PAP I in this cascade and in flagella function. Transcription of flhDC, fliA, and fliC was decreased in the PAP I mutant. These results provide evidence that polyadenylation positively controls the expression of genes belonging to the flagellar biosynthesis pathway and that this effect is mediated through the FlhDC master regulator. However, the downshift in flagella gene expression in the mutant strain did not provoke any noticeable defects in the synthesis of flagella, in biofilm formation and in swimming speed although there was a reduction in motility on soft agar. Our data support an alternative hypothesis that the reduced motility of the mutant resulted from an alteration of the cell membrane composition caused in part by the higher level of GlmS (Glucosamine-6P synthase) which accumulates in the mutant. In agreement with this hypothesis the mutant is more sensitive to hydrophobic agents and antibiotics and in particular to vancomycin. We propose that PAP I participates in the ability of the bacteria to adapt to and survive detrimental conditions by constantly monitoring and adjusting to its environment.
authors.affiliation: CNRS UPR9073, associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005 Paris, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Maes
authors.forename: Céline
authors.initials: C
authors.lastname: Gracia
authors.forename: Dominique
authors.initials: D
authors.lastname: Bréchemier
authors.forename: Philippe
authors.initials: P
authors.lastname: Hamman
authors.forename: Elodie
authors.initials: E
authors.lastname: Chatre
authors.forename: Laurence
authors.initials: L
authors.lastname: Lemelle
authors.forename: Philippe N
authors.initials: PN
authors.lastname: Bertin
authors.forename: Eliane
authors.initials: E
authors.lastname: Hajnsdorf
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D005407:Flagella / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D005408:Flagellin / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation; D026723:Polyadenylation / Q000187:drug effects; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014640:Vancomycin / Q000494:pharmacology; D005945:Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing)
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D005408:Flagellin; D011062:Polynucleotide Adenylyltransferase; D012808:Sigma Factor; D015534:Trans-Activators; D014640:Vancomycin; C516095:FliC protein, E coli; C090552:flhC protein, E coli; C090553:flhD protein, E coli; C063202:sporulation-specific sigma factors; C063643:pcnB protein, E coli; C000731191:component S, glutamate mutase protein, Bacteria; D005945:Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing)