A newly defined dioxygenase system from Mycobacterium vanbaalenii PYR-1 endowed with an enhanced activity of dihydroxylation of high-molecular-weight polyaromatic hydrocarbons
- 8 Downloads
NidA3B3 is a terminal dioxygenase whose favorable substrates are high-molecular-weight polyaromatic hydrocarbons (PAHs) from Mycobacterium vanbaalenii PYR-1, a powerful PAHs degradation strain. NidA3B3 was reported to incorporate a dioxygen into the benzene ring of PAHs when equipped with an exogenous electron transport chain components PhdCD from Nocardioides sp. strain KP7 by biotransformation, but this enzyme system was not particularly efficient. In this study, strain PYR-1 was confirmed to utilize four different PAHs at different growth rates. When PhtAcAd, an endogenous electron transport chain ofa phthalate dioxygenase system, was substituted for PhdCD to couple with NidA3B3, the specific activity to convert phenanthrene by strain BL21(DE3) [pNidA3B3-PhAcAd] was 0.15±0.03 U/mg, but the specificactivity of strain BL21(DE3) [pNidA3B3-PhdCD] was only 0.025±0.006 U/mg. In addition, FNidA3, encoded by a newly defined ORF, has a prolonged 19-amino acid sequence at the N-terminus compared with NidA3. FNidA3B3 increased the activity by 50% approximately than NidA3B3 when using PhtAcAd. Components of the electron transport chain PhtAc and PhtAd were purified and characterized. The Km, kcat, kcat/Km values of the PhtAd were 123±26.9 µM, 503±49.9 min−1, 4.1 µM−1 ×min−1, respectively. And the; Km, kcat, kcat/Km values of the ferredoxin PhtAc were 52.5±9.7 µM, 3.8±0.19 min−1 and 0.07 µM−1×min−1 respectively. Basing on the phylogenetic analysis, NidA3/FNidA3 were far from its isoenzyme NidA from the same strain. Combining their primary differences of transcriptional pattern in vivo, it indicated that the functionally similar Rieske dioxygenases NidA3B3/FNidA3B3 and NidAB might originate from different ancestors.
KeywordsBiodegradation Polyaromatic hydrocarbons Biotransformation Ring-hydroxylating dioxygenase system
This work is supported by the National Key R&D Program of China (Grant No. 2018YFC0309800), National Natural Science Foundation of China (Grant No. 31570100) and Shanghai Science and Technology Commission Scientific Research Project (No. 17JC1403300).
- Boldrin B, Tiehm A, Fritzsche C (1993). Degradation of phenanthrene, fluorene, fluoranthene, and pyrene by a Mycobacterium sp. Applied and Environmental Microbiology, 59(6): 1927–1930Google Scholar
- Boström C E, Gerde P, Hanberg A, Jernström B, Johansson C, Kyrklund T, Rannug A, Törnqvist M, Victorin K, Westerholm R (2002). Cancer risk assessment, indicators, and guidelines for polycyclic aromatic hydrocarbons in the ambient air. Environmental Health Perspectives, 110(Suppl 3): 451–488CrossRefGoogle Scholar
- Ensley B D, Gibson D T (1983). Naphthalene dioxygenase: Purification and properties of a terminal oxygenase component. Journal of Bacteriology, 155(2): 505–511Google Scholar
- Heitkamp M A, Franklin W, Cerniglia C E (1988). Microbial metabolism of polycyclic aromatic hydrocarbons: Isolation and characterization of a pyrene-degrading bacterium. Applied and Environmental Microbiology, 54(10): 2549–2555Google Scholar
- Khan A A, Wang R F, Cao W W, Doerge D R, Wennerstrom D, Cerniglia C E (2001). Molecular cloning, nucleotide sequence, and expression ofgenes encoding a polycyclic aromatic ring dioxygenase from Mycobacterium sp. strain PYR-1. Applied and Environmental Microbiology, 67(8): 3577–3585CrossRefGoogle Scholar
- Kim S J, Kweon O, Freeman J P, Jones R C, Adjei M D, Jhoo J W, Edmondson R D, Cerniglia C E (2006). Molecular cloning and expression of genes encoding a novel dioxygenase involved in low-and high-molecular-weight polycyclic aromatic hydrocarbon degradation in Mycobacterium vanbaalenii PYR-1. Applied and Environmental Microbiology, 72(2): 1045–1054CrossRefGoogle Scholar
- Kweon O, Kim S J, Kim D W, Kim J M, Kim H L, Ahn Y, Sutherland J B, Cerniglia C E (2014). Pleiotropic and epistatic behavior of a ring-hydroxylating oxygenase system in the polycyclic aromatic hydrocarbon metabolic network from Mycobacterium vanbaalenii PYR-1. Journal of Bacteriology, 196(19): 3503–3515CrossRefGoogle Scholar
- McLean K, Dunford A, Sabri M, Neeli R, Girvan H, Balding P, Leys D, Seward H, Marshall K, Munro A (2006). CYP121, CYP51 and Associated Redox Systems in Mycobacterium tuberculosis: Towards Deconvoluting Enzymology of P450 Systems in a Human Pathogen. London: Portland Press LimitedGoogle Scholar
- Schneider J, Grosser R, Jayasimhulu K, Xue W, Warshawsky D (1996). Degradation of pyrene, benz[a]anthracene, and benzo[a]pyrene by Mycobacterium sp. strain RJGII-135, isolated from a former coal gasification site. Applied and Environmental Microbiology, 62(1): 13–19Google Scholar
- Yu C L, Liu W, Ferraro D J, Brown E N, Parales J V, Ramaswamy S, Zylstra G J, Gibson D T, Parales R E (2007). Purification, characterization, and crystallization of the components ofa biphenyl dioxygenase system from Sphingobium yanoikuyae B1. Journal of Industrial Microbiology & Biotechnology, 34(4): 311–324CrossRefGoogle Scholar