Abstract
The use of bacteria is a good method for biodegradation of polycyclic aromatic hydrocarbons due to their fast-growing and cost effectiveness. Bacteria can completely mineralize such toxic compounds to harmless by-products. ASU-035 is a bacterial strain, which was isolated from oil contaminated soil. It was identified as
Achromobacter denitrificans
on the basis of the nucleotide sequence of 16S rRNA gene, and deposited in GenBank under accession number KC342253.
Achromobacter denitrificans
have been tested for utilization of pyrene as a sole source of carbon and energy. Some pyrene degradative enzymes and ability of this strain for biosurfactants production have been studied. The results illustrated that the strain could utilize 76.5 mg/L of pyrene (100 mg/L) within 18 days with growth rate and mean generation time 0.033 h
−1
and 30.3 h, respectively. The maximum specific activities (U/mg protein) of pyrene dioxygenase, catechol 1,2 dioxygenase (
C12O
), and catechol 2,3 dioxygenase (
C23O
) were 0.78 ± 0.12, 0.41 ± 0.05, and 0.2 ± 0.01, respectively.
Achromobacter denitrificans
could enhance the bioavailability of pyrene to get use of it as a sole carbon source by increasing the emulsification activity to 11.5 ± 2.1 U/mg proteins and cell-surface hydrophobicity to 39 ± 1.3 %.