title: The metabolic cost of flagellar motion in Pseudomonas putida KT2440.
abstract: Although the flagellar machinery of environmental bacteria endows cells with a phenomenal survival device, it also consumes much of the metabolic currency necessary for fuelling such a vigorous nano-motor. The physiological cost of flagella-related functions of the soil bacterium Pseudomonas putida KT2440 was examined and quantified through the deletion of a ≈ 70 kb DNA segment of the genome (≈ 1.1%), which includes relevant structural and regulatory genes in this micro-organism. The resulting strain lacked the protruding polar cords that define flagella in the wild-type P. putida strain and was unable of any swimming motility while showing a significant change in surface hydrophobicity. However, these deficiencies were otherwise concomitant with clear physiological advantages: rapid adaptation of the deleted strain to both glycolytic and gluconeogenic carbon sources, increased energy charge and, most remarkably, improved tolerance to oxidative stress, reflecting an increased NADPH/NADP(+) ratio. These qualities improve the endurance of non-flagellated cells to the metabolic fatigue associated with rapid growth in rich medium. Thus, flagellar motility represents the archetypal tradeoff involved in acquiring environmental advantages at the cost of a considerable metabolic burden.
authors.affiliation: Systems Biology Program, Centro Nacional de Biotecnología-CSIC, Campus de Cantoblanco, 28049, Madrid, Spain.
authors.forename: Esteban
authors.initials: E
authors.lastname: Martínez-García
authors.forename: Pablo I
authors.initials: PI
authors.lastname: Nikel
authors.forename: Max
authors.initials: M
authors.lastname: Chavarría
authors.forename: Víctor
authors.initials: V
authors.lastname: de Lorenzo
mesh_terms: D004734:Energy Metabolism; D005407:Flagella / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D016680:Genome, Bacterial; D009249:NADP / Q000378:metabolism; D018384:Oxidative Stress; D016958:Pseudomonas putida / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D009249:NADP