Successive transformation of benzo[a]pyrene by laccase of Trametes versicolor and pyrene-degrading Mycobacterium strains

Appl Microbiol Biotechnol. 2013 Apr;97(7):3183-94. doi: 10.1007/s00253-012-4120-2. Epub 2012 May 11.

Abstract

We previously hypothesized that polycyclic aromatic hydrocarbon (PAH)-degrading bacteria that produce laccase may enhance the degree of benzo[a]pyrene mineralization. However, whether the metabolites of benzo[a]pyrene oxidized by laccase can be further transformed by PAH degraders remains unknown. In this study, pyrene-degrading mycobacteria with diverse degradation properties were isolated and employed for investigating the subsequent transformation on the metabolites of benzo[a]pyrene oxidized by fungal laccase of Trametes versicolor. The results confirm the successive transformation of benzo[a]pyrene metabolites, 6-benzo[a]pyrenyl acetate, and quinones by Mycobacterium strains, and report the discovery of the involvement of a O-methylation mediated pathway in the process. In detail, the vast majority of metabolite 6-benzo[a]pyrenyl acetate was transformed into benzo[a]pyrene quinones or methoxybenzo[a]pyrene, via two distinct steps that were controlled by the catechol-O-methyltransferase mediated O-methylation, while quinones were reduced to dihydroxybenzo[a]pyrene and further transformed into dimethoxy derivatives.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzo(a)pyrene / metabolism*
  • Biotransformation
  • Cluster Analysis
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • DNA, Ribosomal / chemistry
  • DNA, Ribosomal / genetics
  • Laccase / metabolism*
  • Molecular Sequence Data
  • Mycobacterium / metabolism*
  • Oxidation-Reduction
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA
  • Trametes / enzymology*

Substances

  • DNA, Bacterial
  • DNA, Ribosomal
  • RNA, Ribosomal, 16S
  • Benzo(a)pyrene
  • Laccase

Associated data

  • GENBANK/AB618674
  • GENBANK/AB618675
  • GENBANK/AB618676
  • GENBANK/AB618677
  • GENBANK/AB618678