Stereoselective fungal metabolism of 7,12-dimethylbenz(a)anthracene: identification and enantiomeric resolution of a K-region dihydrodiol

Journal Article · Thu Oct 01 04:00:00 EDT 1987 · Appl. Environ. Microbiol.; (United States)

OSTI ID:6939544

McMillan, D C; Fu, P P; Cerniglia, C E

Syncephalastrum racemosum UT-70 and Cunninghamella elegans ATCC 36112 metabolized 7,12-dimethylbenz(a)anthracene (7,12-DMBA) to hydroxymethyl metabolites as well as 7-hydroxymethyl-12-methylbenz(a)anthracene trans-3,4-, -5,6-, -8,9-, and -10,11-dihydrodiols. The 7,12-DMBA metabolites were isolated by reversed-phase high-performance liquid chromatography and identified by their UV-visible absorption, mass, and nuclear magnetic resonance spectral characteristics. A comparison of the circular dichroism spectra of the K-region (5,6-position) dihydrodiol of both fungal strains with those of the 7,12-DMBA 5S,6S-dihydrodiol formed from 7,12-DMBA by rat liver microsomes indicated that the major enantiomer of the 7-hydroxymethyl-12-methylbenz(a)anthracene trans-5,6-dihydrodiol formed by both fungal strains had a 5R,6R absolute stereochemistry. Direct resolution of the fungal trans-5,6-dihydrodiols by chiral stationary-phase high-performance liquid chromatography indicated that the ratios of the R,R and S,S, enantiomers were 88:12 and 77:23 for S. racemosum and C. elegans, respectively. These results indicate that the fungal metabolism of 7,12-DMBA at the K region (5,6-position) is highly stereoselective and different from that reported for mammalian enzyme systems.

• Research Organization: Food and Drug Administration, Jefferson, AR (USA)
• OSTI ID: 6939544
• Journal Information: Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 53:10; ISSN AEMID
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
AROMATICS
BENZANTHRACENE
BIOLOGICAL VARIABILITY
BODY
CELL CONSTITUENTS
CHROMATOGRAPHY
CONDENSED AROMATICS
DIGESTIVE SYSTEM
FUNGI
GENETIC VARIABILITY
GLANDS
HYDROCARBONS
LIQUID COLUMN CHROMATOGRAPHY
LIVER
MAGNETIC RESONANCE
MAMMALS
MASS SPECTRA
METABOLISM
METABOLITES
MICROSOMES
NUCLEAR MAGNETIC RESONANCE
ORGANIC COMPOUNDS
ORGANOIDS
ORGANS
PLANTS
RATS
RESONANCE
RODENTS
SEPARATION PROCESSES
SPECTRA
VERTEBRATES