Novel organization of genes in a phthalate degradation operon of Mycobacterium vanbaalenii PYR-1.
Mycobacterium vanbaalenii PYR-1 is capable of degrading polycyclic aromatic hydrocarbons (PAHs) to ring cleavage metabolites. This study identified and characterized a putative phthalate degradation operon in the M. vanbaalenii PYR-1 genome. A putative regulatory protein (phtR) was encoded divergently with five tandem genes: phthalate dioxygenase large subunit (phtAa), small subunit (phtAb), phthalate dihydrodiol dehydrogenase (phtB), phthalate dioxygenase ferredoxin subunit (phtAc) and phthalate dioxygenase ferredoxin reductase (phtAd). A 6.7 kb EcoRI fragment containing these genes was cloned into Escherichia coli and converted phthalate to 3,4-dihydroxyphthalate. Homologues to the operon region were detected in a number of PAH-degrading Mycobacterium spp. isolated from various geographical locations. The operon differs from those of other Gram-positive bacteria in both the placement and orientation of the regulatory gene. In addition, the M. vanbaalenii PYR-1 pht operon contains no decarboxylase gene and none was identified within a 37 kb region containing the operon. This study is the first report of a phthalate degradation operon in Mycobacterium spp.
Stingley
Robin L
RL
Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA.
Brezna
Barbara
B
Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovakia.|Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA.
Khan
Ashraf A
AA
Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA.
Cerniglia
Carl E
CE
Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA.
D020134:Catalytic Domain / Q000235:genetics; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D023061:Gene Order; D005798:Genes, Bacterial; D006094:Gram-Positive Bacteria / Q000235:genetics; D008969:Molecular Sequence Data; D009161:Mycobacterium / Q000235:genetics* / Q000378:metabolism; D009876:Operon; D010105:Oxygenases / Q000235:genetics; D010795:Phthalic Acids / Q000378:metabolism*; D010802:Phylogeny; D021122:Protein Subunits / Q000235:genetics; D017422:Sequence Analysis, DNA; D026801:Synteny
D004269:DNA, Bacterial; D010795:Phthalic Acids; D021122:Protein Subunits; C032279:phthalic acid; C036017:3,4-dihydroxyphthalic acid; D010105:Oxygenases; C044732:phthalate dioxygenase