DEGRADATION PATHWAYS AND MECHANISMS OF SUBSTITUTED INDOLES UNDER METHANOGENIC CONDITION

TY - JOUR

T1 - DEGRADATION PATHWAYS AND MECHANISMS OF SUBSTITUTED INDOLES UNDER METHANOGENIC CONDITION

AU - Wang, Yingying

AU - Qiu, Wanfei

AU - Fan, Yanzhen

AU - Gu, Ji-Dong

PY - 2002

Y1 - 2002

N2 - Degradation of indole by an indoledegrading methanogenic consortium enriched from sewage sludge proceeded through a twostep hydroxylation pathway yielding oxindole and isatin. The ability of this consortium to hydroxylate and subsequently degrade substituted indoles was investigated. Of the substituted indoles tested, the consortium was able to transform or degrade 3 methylindole and 3indolyl acetate. Oxindole, 3methyloxindole, and indoxyl were identified as degradation metabolites of indole, 3methylindole, and 3indolyl acetate, respectively. Isatin (indole2, 3dione) was produced as an intermediate when the consortium was amended with oxindole, which provided the evidence that degradation of indole proceeded through successive hydroxylation of the 2 and 3positions prior to ring cleavage between the C2 and C3 atoms on the pyrrole ring of indole. The presence of a methyl group ( CH3) at either the 1 or 2position of indole inhibited the initial hydroxylation reaction. The substituted indole, 3methylindole, was hydroxylated at the 2position but not at the 3position and could not be further metabolized through the oxindoleisatin pathway. Indoxyl (indole3one), the deacetylated product of 3 indolyl acetate, was not hydroxylated at the 2position and thus was not further metabolized by the consortium. When an H atom or electrondonating group (i.e., CH3) was present at the 3 position, hydroxylation proceeded at the 2position, but the presence of electronwithdrawing substituent groups (i.e.,OH orCOOH) at the 3position inhibited hydroxylation. Tab 1, Fig 4, Ref 25

AB - Degradation of indole by an indoledegrading methanogenic consortium enriched from sewage sludge proceeded through a twostep hydroxylation pathway yielding oxindole and isatin. The ability of this consortium to hydroxylate and subsequently degrade substituted indoles was investigated. Of the substituted indoles tested, the consortium was able to transform or degrade 3 methylindole and 3indolyl acetate. Oxindole, 3methyloxindole, and indoxyl were identified as degradation metabolites of indole, 3methylindole, and 3indolyl acetate, respectively. Isatin (indole2, 3dione) was produced as an intermediate when the consortium was amended with oxindole, which provided the evidence that degradation of indole proceeded through successive hydroxylation of the 2 and 3positions prior to ring cleavage between the C2 and C3 atoms on the pyrrole ring of indole. The presence of a methyl group ( CH3) at either the 1 or 2position of indole inhibited the initial hydroxylation reaction. The substituted indole, 3methylindole, was hydroxylated at the 2position but not at the 3position and could not be further metabolized through the oxindoleisatin pathway. Indoxyl (indole3one), the deacetylated product of 3 indolyl acetate, was not hydroxylated at the 2position and thus was not further metabolized by the consortium. When an H atom or electrondonating group (i.e., CH3) was present at the 3 position, hydroxylation proceeded at the 2position, but the presence of electronwithdrawing substituent groups (i.e.,OH orCOOH) at the 3position inhibited hydroxylation. Tab 1, Fig 4, Ref 25

KW - indoles

KW - pathway

KW - methanogenic condition

UR - http://www.cibj.com/Upload/PaperUpLoad/ebook/2002/05/14.pdf

M3 - 文章

JO - Chinese Journal of Appplied Environmental Biology

JF - Chinese Journal of Appplied Environmental Biology

ER -