Isolation and characterization of (+)-1,1a-dihydroxy-1-hydrofluoren-9-one formed by angular dioxygenation in the bacterial catabolism of fluorene.
Transformation of fluorene by washed cells of fluorene-grown Pseudomonas sp. F274 yielded 1,la-dihydroxy-1-hydrofluoren-9-one (up to 100 mg/l) as the stable product of angular dioxygenation of 9-fluorenone. Structural identity of the angular keto-diol was established by 13C- and 1H-NMR, gas chromatography- and direct probe-mass spectrometry. Definitive assignment of 1,1a-dioxygenation, but not 4,4a-, was based on the isolation and rigorous identification of 1-hydroxyfluoren-9-one as the exclusive product of acidic dehydration. Chiral 1H-NMR analysis and optical rotation of isolated 1,1a-dihydroxy-1-hydrofluoren-9-one ([alpha]D = + 132.1 degrees) are indicative of a single enantiomer with an inferred cis-stereochemistry of the hydroxyl groups. This compound is evidently an intermediate of fluorene catabolism by this strain and not a dead-end product because its formation is transient in washed cell incubations and ultimately it is completely consumed with the formation of acidic metabolites.
Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola 32514.
S A
SA
Selifonov
M
M
Grifoll
J E
JE
Gurst
P J
PJ
Chapman
D005449:Fluorenes / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D010100:Oxygen / Q000378:metabolism*; D011549:Pseudomonas / Q000378:metabolism*; D013237:Stereoisomerism
D005449:Fluorenes; C081458:1,1a-dihydroxy-1-hydrofluoren-9-one; D010100:Oxygen