title: Key high molecular weight PAH-degrading bacteria in a soil consortium enriched using a sand-in-liquid microcosm system.
abstract: A novel biphasic system containing mineral medium and sand coated with a biologically weathered creosote-PAH mixture was developed to specifically enrich the high molecular weight polycyclic aromatic hydrocarbon (HMW PAH)-degrading community from a creosote-polluted soil. This consortium (UBHP) removed 70% of the total HMW PAHs and their alkyl-derivatives in 12 weeks. Based on a combined culture-dependent/independent approach, including clone library analysis, detection of catabolic genes, metabolomic profiles, and characterization of bacterial isolates, 10 phylotypes corresponding to five major genera (Sphingobium, Sphingomonas, Achromobacter, Pseudomonas, and Mycobacterium) were pointed out as key players within the community. In response to exposure to different single PAHs, members of sphingomonads were associated to the utilization of phenanthrene, fluoranthene, benzo[a]anthracene, and chrysene, while the degradation of pyrene was mainly associated to low-abundance mycobacteria. In addition to them, a number of uncultured phylotypes were detected, being of special relevance a group of Gammaproteobacteria closely related to a group previously associated with pyrene degradation that were here related to benzo(a)anthracene degradation. The overall environmental relevance of these phylotypes was confirmed by pyrosequencing analysis of the microbial community shift in the creosote-polluted soil during a lab-scale biostimulation.
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Diagonal 643, 08028, Barcelona, Spain.
authors.forename: Margalida
authors.initials: M
authors.lastname: Tauler
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Diagonal 643, 08028, Barcelona, Spain.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Vila
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Diagonal 643, 08028, Barcelona, Spain.
authors.forename: José María
authors.initials: JM
authors.lastname: Nieto
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Diagonal 643, 08028, Barcelona, Spain. mgrifoll@ub.edu.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Grifoll
mesh_terms: D042402:Achromobacter / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000873:Anthracenes / Q000378:metabolism; D001673:Biodegradation, Environmental; D020563:Gammaproteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D015723:Gene Library; D059014:High-Throughput Nucleotide Sequencing; D059013:Microbial Consortia / Q000235:genetics; D009161:Mycobacterium / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D010616:Phenanthrenes / Q000378:metabolism; D010802:Phylogeny; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D011549:Pseudomonas / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D011721:Pyrenes / Q000378:metabolism; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D013030:Spain; D042301:Sphingomonadaceae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000873:Anthracenes; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D011721:Pyrenes; D012987:Soil; D012989:Soil Pollutants
keywords: Biodegradation; Microbial community analysis; Microbial consortium; PAHs; Polluted soil