Bacterial and fungal oxidation of dibenzofuran.

Abstract

Cunninghamella elegans and a mutant strain (B8/36) of Beijerinckia both oxidized dibenzofuran to 2,3-dihydroxy-2,3-dihydrodibenzofuran. The bacterial metabolite was extremely unstable and, in the presence of acid, was rapidly converted into a mixture of 2- and 3-hydroxydibenzofuran. In contrast, the 2,3-dihydroxy-2,3-dihydrodibenzofuran formed by C. elegans was stable and only yielded 2- and 3-hydroxydibenzofuran when heated under acidic conditions. The results suggest that Beijerinckia B8/36 and C. elegans form the respective cis- and trans-isomers of 2,3-dihydroxy-2,3-dihydrodibenzofuran. C. elegans also oxidized dibenzofuran to 2- and 3-hydroxydibenzofuran under conditions that would not lead to the dehydration of the trans-dihydrodiol. These observations implicate the initial formation of dibenzofuran- 2,3-epoxide in the fungal oxidation of dibenzofuran. Beijerinckia B8/36 also produced a second unstable dihydrodiol that was tentatively identified as cis-1,2-dihydroxy-1,2-dihydrodibenzofuran. This compound gave 2-hydroxydibenzofuran as the major dehydration product and the cis relative stereochemistry was suggested by the isolation and characterization of an isopropylidine derivative. A preparation of cis-naphthalene dihydrodiol dehydrogenase and cell extracts of the parent strain of Beijerinckia oxidized both bacterial dihydrodiols to catechols. Cell extracts prepared from C. elegans catalysed an analogous oxidation of trans-2,3-dihydroxy-2,3-dihydrodibenzofuran to 2,3-dihydroxydibenzofuran. The latter product was also isolated and identified from culture filtrates. The results suggest that bacteria and fungi utilize different mechanisms to initiate the oxidation of dibenzofuran.

• Authors: C E Cerniglia, J C Morgan, D T Gibson
• Journal: The Biochemical journal (Biochem J) Vol. 180 Issue 1 Pg. 175-85 (Apr 15 1979) ISSN: 0264-6021 [Print] England
• PMID: 486097 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Benzofurans

Topics

• Bacteria (metabolism)
• Benzofurans (metabolism)
• Chemical Phenomena
• Chemistry
• Fungi (metabolism)
• Oxidation-Reduction
• Spectrophotometry