Dihydroxylation of four- and five-ring aromatic hydrocarbons by the naphthalene dioxygenase from Sphingomonas CHY-1

Jouanneau, Y; Meyer, C; Duraffourg, N

HERO ID

3035903

Reference Type

Journal Article

Year

2015

Language

English

PMID

26476651

HERO ID 3035903
In Press No
Year 2015
Title Dihydroxylation of four- and five-ring aromatic hydrocarbons by the naphthalene dioxygenase from Sphingomonas CHY-1
Authors Jouanneau, Y; Meyer, C; Duraffourg, N
Journal Applied Microbiology and Biotechnology
Volume 100
Issue 3
Page Numbers 1253-1263
Abstract The naphthalene dioxygenase from Sphingomonas CHY-1 exhibits extremely broad substrate specificity toward polycyclic aromatic hydrocarbons (PAHs). In a previous study, the catalytic rates of oxidation of nine PAHs were determined using the purified dioxygenase, but the oxidation products formed from four- to five-ring hydrocarbons were incompletely characterized. Here, we reexamined PAH oxygenation reactions using Escherichia coli recombinant cells overproducing strain CHY-1 dioxygenase. Hydroxylated products generated by the dioxygenase were purified and characterized by means of GC-MS, UV absorbance as well as (1)H- and (13)C-NMR spectroscopy. Fluoranthene was converted to three dihydrodiols, the most abundant of which was identified as cis-7,8-dihydroxy-7,8-dihydrofluoranthene. This diol turned out to be highly unstable, converting to 8-hydroxyfluoranthene by spontaneous dehydration. The dioxygenase also catalyzed dihydroxylations on the C2-C3 and presumably the C1-C2 positions, although at much lower rates. Benz[a]anthracene was converted into three dihydrodiols, hydroxylated in positions C1-C2, C8-C9, and C10-C11, and one bis-cis-dihydrodiol. The latter compound was identified as cis,cis-1,2,10,11-tetrahydroxy-1,2,10,11-tetrahydrobenz[a]anthracene, which resulted from the subsequent dioxygenation of the 1,2- or 10,11-dihydrodiols. Chrysene dioxygenation yielded a single diol identified as cis-3,4-dihydroxy-3,4-dihydrochrysene, which underwent further oxidation to give cis,cis-3,4,9,10 chrysene tetraol. Pyrene was a poor substrate for the CHY-1 dioxygenase and gave a single dihydrodiol hydroxylated on C4 and C5, whereas benzo[a}pyrene was converted to two dihydrodiols, one of which was identified as cis-9,10-dihydrodiol. The selectivity of the dioxygenase is discussed in the light of the known 3D structure of its catalytic component and compared to that of the few enzymes able to attack four- and five-ring PAHs.
Doi 10.1007/s00253-015-7050-y
Pmid 26476651
Wosid WOS:000369308900017
Url <Go to ISI>://WOS:000369308900017
Is Certified Translation No
Dupe Override No
Comments Scopus URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84955199690&doi=10.1007%2fs00253-015-7050-y&partnerID=40&md5=ca27543592b4510079deb0759440304a
Is Public Yes
Language Text English
Keyword Ring hydroxylation; Dioxygenase; cis-Dihydrodiols; PAH; Regioselectivity
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