title: Phylogenetic and functional diversity of alkane degrading bacteria associated with Italian ryegrass (Lolium multiflorum) and Birdsfoot trefoil (Lotus corniculatus) in a petroleum oil-contaminated environment.
abstract: Twenty-six different plant species were analyzed regarding their performance in soil contaminated with petroleum oil. Two well-performing species, Italian ryegrass (Lolium multiflorum var. Taurus), Birdsfoot trefoil (Lotus corniculatus var. Leo) and the combination of these two plants were selected to study the ecology of plant-associated, culturable alkane-degrading bacteria. Hydrocarbon degrading bacteria were isolated from the rhizosphere, root interior and shoot interior and subjected to the analysis of 16S rRNA gene, the 16S and 23S rRNA intergenic spacer region and alkane hydroxylase genes. Furthermore, we investigated whether alkane hydroxylase genes are plasmid located. Higher numbers of culturable, alkane-degrading bacteria were associated with Italian ryegrass, which were also characterized by a higher diversity, particularly in the plant interior. Only half of the isolated bacteria hosted known alkane hydroxylase genes (alkB and cytochrome P153-like). Degradation genes were found both on plasmids as well as in the chromosome. In regard to application of plants for rhizodegradation, where support of numerous degrading bacteria is essential for efficient break-down of pollutants, Italian ryegrass seems to be more appropriate than Birdsfoot trefoil.
authors.affiliation: Bioresources Unit, AIT Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria.
authors.forename: Sohail
authors.initials: S
authors.lastname: Yousaf
authors.affiliation: Bioresources Unit, AIT Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria.
authors.forename: Verania
authors.initials: V
authors.lastname: Andria
authors.affiliation: Unit of Environmental Resources & Technologies, AIT Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Reichenauer
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, D-38104 Braunschweig, Germany.
authors.forename: Kornelia
authors.initials: K
authors.lastname: Smalla
authors.affiliation: Bioresources Unit, AIT Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria. Electronic address: angela.sessitsch@ait.ac.at.
authors.forename: Angela
authors.initials: A
authors.lastname: Sessitsch
mesh_terms: D000473:Alkanes / Q000378:metabolism*; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D017931:DNA Primers; D008129:Lolium / Q000378:metabolism* / Q000382:microbiology; D000070116:Lotus / Q000378:metabolism* / Q000382:microbiology; D010578:Petroleum; D010802:Phylogeny; D010957:Plasmids; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012338:RNA, Ribosomal, 23S / Q000235:genetics
chemical_list: D000473:Alkanes; D017931:DNA Primers; D010578:Petroleum; D012336:RNA, Ribosomal, 16S; D012338:RNA, Ribosomal, 23S