TY - JOUR
T1 - Relationship between structures of substituted indolic compounds and their degradation by marine anaerobic microorganisms
AU - Gu, Ji Dong
AU - Fan, Yanzhen
AU - Shi, Hanchang
N1 - Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2002/9
Y1 - 2002/9
N2 - Degradation of selected indolic compounds including indole, 1-methylindole, 2-methylindole, and 3-methylindole was assessed under methanogenic and sulfate-reducing conditions using the serum-bottle anaerobic technique and marine sediment from Victoria Harbour, Hong Kong as an inoculum. Our results showed that indole degradation was achieved in 28 days by a methanogenic consortium and 35 days by a sulfate-reducing consortium. During degradation under both conditions, two intermediates were isolated, purified and identified as oxindole and isatin (indole-2,3-dione) suggesting that both methanogenic and sulfate-reducing bacteria use an identical degradation pathway. Degradation processes followed two steps of oxidation accomplished by hydroxylation and then dehydrogenation at 2- and then 3-position sequentially prior to the cleavage of the pyrrole ring between 2- and 3-positions. However, none of 1-methylindole or 2-methylindole was degraded under any conditions. 3-Methylindole (3-methyl-1H-indole, skatole) was transformed under methanogenic conditions and mineralized only under sulfate-reducing conditions. It is clear that methyl substitution on 1- or 2-position inhibits the initial attack by hydroxylation enzymes making them more persistent in the environment and posing longer toxic impact.
AB - Degradation of selected indolic compounds including indole, 1-methylindole, 2-methylindole, and 3-methylindole was assessed under methanogenic and sulfate-reducing conditions using the serum-bottle anaerobic technique and marine sediment from Victoria Harbour, Hong Kong as an inoculum. Our results showed that indole degradation was achieved in 28 days by a methanogenic consortium and 35 days by a sulfate-reducing consortium. During degradation under both conditions, two intermediates were isolated, purified and identified as oxindole and isatin (indole-2,3-dione) suggesting that both methanogenic and sulfate-reducing bacteria use an identical degradation pathway. Degradation processes followed two steps of oxidation accomplished by hydroxylation and then dehydrogenation at 2- and then 3-position sequentially prior to the cleavage of the pyrrole ring between 2- and 3-positions. However, none of 1-methylindole or 2-methylindole was degraded under any conditions. 3-Methylindole (3-methyl-1H-indole, skatole) was transformed under methanogenic conditions and mineralized only under sulfate-reducing conditions. It is clear that methyl substitution on 1- or 2-position inhibits the initial attack by hydroxylation enzymes making them more persistent in the environment and posing longer toxic impact.
KW - Anaerobic degradation
KW - Indole
KW - Metabolic pathway
KW - Methanogenic condition
KW - Substitution
KW - Sulfate-reducing condition
UR - http://www.scopus.com/inward/record.url?scp=0036741558&partnerID=8YFLogxK
U2 - 10.1016/S0025-326X(02)00091-7
DO - 10.1016/S0025-326X(02)00091-7
M3 - 文章
C2 - 12398409
AN - SCOPUS:0036741558
VL - 45
SP - 379
EP - 384
JO - Marine Pollution Bulletin
JF - Marine Pollution Bulletin
SN - 0025-326X
IS - 1-12
ER -