title: Metabolic profiling of Burkholderia cenocepacia, Burkholderia ambifaria, and Burkholderia pyrrocinia isolates from maize rhizosphere.
abstract: Burkholderia cenocepacia, Burkholderia ambifaria, and Burkholderia pyrrocinia are the Burkholderia cepacia complex (Bcc) species most frequently associated with roots of crop plants. To investigate the ecophysiological diversity of these species, metabolic profiling of maize rhizosphere isolates was carried out by means of the Biolog system, using GN2 and SFN2 plates and different parameters related to optical density (OD). The metabolic profiles produced by the SFN2 and GN2 plates were identical, but the SFN2's narrower range of OD values and significantly longer reaction times made these plates less suitable for differentiation of isolates. Principal component analysis of maximum OD (ODM) and maximum substrate oxidation rate (muM) data generated by GN2 plates allowed the selection of a reduced number of carbon sources. Statistical analysis of ODM values highlighted marked differences between the metabolic profiles of B. cenocepacia and B. ambifaria, whereas metabolic profiles of B. pyrrocinia clustered very often with those of B. cenocepacia. Analysis of the mu(M) parameter resulted in a slightly lower differentiation among the three Bcc species and a higher metabolic diversity within the single species, in particular within B. cenocepacia. Finally, B. cenocepacia and B. pyrrocinia showed generally higher oxidation rates than B. ambifaria on those GN2 substrates that commonly occur in maize root exudates.
authors.affiliation: Unità Protezione dell'Ambiente, Ente Nazionale per le Nuove Tecnologie, l'Energia e l'Ambiente (ENEA) C. R. Casaccia, Rome, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Alisi
authors.forename: Giovanna Jona
authors.initials: GJ
authors.lastname: Lasinio
authors.forename: Claudia
authors.initials: C
authors.lastname: Dalmastri
authors.forename: AnnaRosa
authors.initials: A
authors.lastname: Sprocati
authors.forename: Silvia
authors.initials: S
authors.lastname: Tabacchioni
authors.forename: Annamaria
authors.initials: A
authors.lastname: Bevivino
authors.forename: Luigi
authors.initials: L
authors.lastname: Chiarini
mesh_terms: D016956:Burkholderia cepacia / Q000145:classification* / Q000378:metabolism; D051639:Gardening; D018517:Plant Roots / Q000382:microbiology; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013379:Substrate Specificity; D003313:Zea mays / Q000382:microbiology*
chemical_list: D011933:Reagent Kits, Diagnostic