ABSTRACT
A Gram-negative bacterium designated UBF-P1(T) was isolated from an enrichment culture established in nutrient supplemented artificial sea water with pyrene as a carbon source, and inoculated with a marine fuel oil-degrading consortium obtained from a sand sample collected from the beach of Corrubedo (A Coruña, Galicia, Spain) after the Prestige accidental oil spill. Phylogenetic analysis based on the almost complete 16S rRNA gene sequence affiliated strain UBF-P1(T) with the family Cohaesibacteraceae, Cohaesibacter gelatinilyticus (DSM 18289(T)) being the closest relative species with 92% sequence similarity. Cells were irregular rods, motile, strictly aerobic, catalase and oxidase positive. Ubiquinone 10 was the major respiratory lipoquinone. The major polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylmonomethylethanolamine (PME), and phosphatidylcholine (PC). The major fatty acids detected were C(18:1)ω7c, C(19:0) cycloω8c, and C(16:0). The G+C content of strain UBF-P1(T) was 63.9 mol%. The taxonomic comparison with the closest relative based on genotypic, phenotypic and chemotaxonomic characteristics supported that strain UBF-P1(T) could be classified as a novel genus and species, for which the name Breoghania corrubedonensis gen. nov., sp. nov. is proposed. The type strain of this new taxon is UBF-P1(T) (CECT 7622, LMG 25482, DSM 23382).
Subject(s)
Alphaproteobacteria/classification , Alphaproteobacteria/isolation & purification , Environmental Microbiology , Alphaproteobacteria/genetics , Alphaproteobacteria/growth & development , Base Composition , Carbon/metabolism , Cluster Analysis , Culture Media/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Environmental Pollutants , Fatty Acids/analysis , Fuel Oils , Molecular Sequence Data , Phospholipids/analysis , Phylogeny , Pyrenes/metabolism , Quinones/analysis , RNA, Ribosomal, 16S/genetics , Seawater/microbiology , Sequence Analysis, DNA , SpainABSTRACT
A marine microbial consortium obtained from a beach contaminated by the Prestige oil spill proved highly efficient in removing the different hydrocarbon families present in this heavy fuel oil. Seawater cultures showed a complete removal of all the linear and branched alkanes, an extensive attack on three to five-ring polycyclic aromatic hydrocarbons [PAHs; including anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, and benzo(a)pyrene] (30-100%), and a considerable depletion of their alkyl derivatives. Community dynamics analysis revealed that Alcanivorax species, known alkane degraders, predominated in the initial stages. This was followed by an increase in Alphaproteobacteria (i.e. Maricaulis, Roseovarius), which coincided with the depletion of low molecular PAHs. Finally, these were succeeded by Gammaproteobacteria (mainly Marinobacter and Methylophaga), which were involved in the degradation of the high molecular-weight PAHs. The role of these populations in the removal of the specific components was confirmed by the analysis of subcultures established using the aliphatic or the aromatic fraction of the fuel oil, or single PAHs, as carbon sources. The genus Marinobacter seemed to play a major role in the degradation of a variety of hydrocarbons, as several members of this group were isolated from the different enrichment cultures and grew on plates with hexadecane or single PAHs as sole carbon sources.
