This HTML5 document contains 27 embedded RDF statements represented using HTML+Microdata notation.

The embedded RDF content will be recognized by any processor of HTML5 Microdata.

Subject Item

n2:w

rdf:type

bibo:Article rdac:C10001

dcterms:isPartOf

n17:w

dcterms:subject

n6:environmentalprocesses n12:article

dcterms:title

Evaluation of Toluene Degradation Pathways by Two-Dimensional Stable Isotope Fractionation

rdaw:P10072

n9:web n9:print

vivo:relatedBy

n5:6 n5:2 n5:4 n5:7 n5:1 n5:3 n5:5 n5:8

marcrel:aut

n2:vogtcarsten n2:herrmannsteffi n2:herklotzilka n2:fischeranko n10:c7b0c7afff0e6b66c1d8b17a077b223b n2:cyrusesther n13:person n2:bahrarne

dcterms:abstract

Toluene degradation by several pure and mixed microbial cultures was investigated by two-dimensional compound specific isotope analysis (2D-CSIA). For most of the cultures, the respective toluene degradation pathway and toluene attacking enzymatic step was known. The slope of the linear regression for hydrogen (Δδ2H) vs carbon (Δδ13C) discrimination (Λ = Δδ2H/Δδ13C ≈ εHbulk/εCbulk) was determined in order to characterize aerobic and anaerobic toluene degradation pathways. The highest Λ value was estimated for the monohydroxylation of the methyl group by Pseudomonas putida (Λ = 53 ± 5). The lowest value was observed for Rhodococcus opacus (Λ = 2 ± 2) due to its insignificant hydrogen fractionation, which indicates that a ring dioxygenase was responsible for the initial attack of toluene. The fungus Cladosprium sphaerospermum containing a cytochrome P450-dependent methyl monooxygenase grouped within these extreme values (Λ = 16 ± 6). Λ values for organisms attacking toluene under anoxic conditions by benzylsuccinate synthase were significantly different and ranged from Λ = 4 ± 3 (Blastochloris sulfoviridis) to 31 ± 11 (strain TRM1). Values were in the same range for organisms using nitrate (Λ = 11−14) or sulfate (Λ = 28−31) as electron acceptor, indicating that it might be possible to distinguish toluene degradation under different electron acceptor conditions by 2D-CSIA. The potential of two-dimensional isotope fractionation analysis to characterize toluene biodegradation pathways under oxic and anoxic conditions is explored in a laboratory study.

hub:isPartOfThisJournal

n15:w