A refinery sludge deposition site: presence of nahH and alkJ genes and crude oil biodegradation ability of bacterial isolates.

204 bacterial isolates from four Greek refinery sludge deposition sites were investigated for the presence of nahH and alkJ genes encoding key enzymes of both aromatic and aliphatic hydrocarbon degradation pathways by PCR and DNA hybridisation. Members of Pseudomonas, Acinetobacter, Bacillus, Rhodococcus and Arthrobacter play important role in bioremediation processes in sandy/loam soil contaminated with oil and nahH and alkJ genes were present in the 73% of the isolates. Consortia of bacterial isolates that were used for biodegradation of aliphatic and aromatic hydrocarbons in crude oil using liquid cultures exhibited rates from 35% to 48% within 10 days of incubation.

Biodegradation of crude oil by thermophilic bacteria isolated from a volcano island.

One-hundred and fifty different thermophilic bacteria isolated from a volcanic island were screened for detection of an alkane hydroxylase gene using degenerated primers developed to amplify genes related to the Pseudomonas putida and Pseudomonas oleovorans alkane hydroxylases. Ten isolates carrying the alkJ gene were further characterized by 16s rDNA gene sequencing. Nine out of ten isolates were phylogenetically affiliated with Geobacillus species and one isolate with Bacillus species.