Metabolism-dependent taxis towards (methyl)phenols is coupled through the most abundant of three polar localized Aer-like proteins of Pseudomonas putida.
Comparatively little is known about directed motility of environmental bacteria to common aromatic pollutants. Here, by expressing different parts of a (methyl)phenol-degradative pathway and the use of specific mutants, we show that taxis of Pseudomonas putida towards (methyl)phenols is dictated by its ability to catabolize the aromatic compound. Thus, in contrast to previously described chemoreceptor-mediated chemotaxis mechanisms towards benzoate, naphthalene and toluene, taxis in response to (methyl)phenols is mediated by metabolism-dependent behaviour. Here we show that P. putida differentially expresses three Aer-like receptors that are all polar-localized through interactions with CheA, and that inactivation of the most abundant Aer2 protein significantly decreases taxis towards phenolics. In addition, the participation of a sensory signal transduction protein composed of a PAS, a GGDEF and an EAL domain in motility towards these compounds is demonstrated. The results are discussed in the context of the versatility of metabolism-dependent coupling and the necessity for P. putida to integrate diverse metabolic signals from its native heterogeneous soil and water environments.
Sarand
Inga
I
Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
Osterberg
Sofia
S
Holmqvist
Sofie
S
Holmfeldt
Per
P
Skärfstad
Eleonore
E
Parales
Rebecca E
RE
Shingler
Victoria
V
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D016764:Cell Polarity; D002633:Chemotaxis; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D000072236:Methyl-Accepting Chemotaxis Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D010636:Phenols / Q000737:chemistry / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011549:Pseudomonas / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D015398:Signal Transduction
D001426:Bacterial Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D010636:Phenols