Mycobacterium vanbaalenii PYR-1 has the ability to degrade low- and high-molecular-weight polycyclic aromatic hydrocarbons (PAHs). In addition to dioxygenases, cytochrome P450 monooxygenases have been implicated in PAH degradation. Three cytochrome P450 genes,
cyp151 (
pipA),
cyp150, and
cyp51, were detected and amplified by polymerase chain reaction from
M. vanbaalenii PYR-1. The complete sequence of these genes was determined. The translated putative proteins were ≥80% identical to other GenBank-listed mycobacterial CYP151, CYP150, and CYP51. Genes
pipA and
cyp150 were cloned, and the proteins partially expressed in
Escherchia coli as soluble heme-containing cytochrome P450s that exhibited a characteristic peak at 450 nm in reduced carbon monoxide difference spectra. Monooxygenation metabolites of pyrene, dibenzothiophene, and 7-methylbenz[α]anthracene were detected in whole cell biotransformations, with
E. coli expressing
pipA or
cyp150 when analyzed by gas chromatography/mass spectrometry. The cytochrome P450 inhibitor metyrapone strongly inhibited the S-oxidation of dibenzothiophene. Thirteen other
Mycobacterium strains were screened for the presence of
pipA,
cyp150, and
cyp51 genes, as well as the initial PAH dioxygenase (
nidA and
nidB). The results indicated that many of the
Mycobacterium spp. surveyed contain both monooxygenases and dioxygenases to degrade PAHs. Our results provide further evidence for the diverse enzymatic capability of
Mycobacterium spp. to metabolize polycylic aromatic hydrocarbons.
An erratum to this article can be found at
http://dx.doi.org/10.1007/s00253-006-0360-3