Quantification of catechol 2,3-dioxygenase gene homology and benzoate utilization in intertidal sediments

Abstract

The catechol 2,3-dioxygenase (C230) gene, xylE, from the TOL plasmid pathway was used to probe naturally occurring bacterial communities in an intertidal microbial mat. Bound probe was quantified by densitometric analysis of slot blots using colorimetric detection of hybridization between the probe and total DNA extracts from the sediments. The C230 gene encodes the key ringbrealung enzyme of the toluene degradation pathway, of which benzoate is an intermediate. Radiotracer experiments using I4C-benzoate detected benzoate mineralization in these sedirnents, corroborating the presence of both the genetic potential and in situ actlvity for this transformation.

Quantification of Subfamily I.2.C Catechol 2,3-Dioxygenase mRNA Transcripts in Groundwater Samples of an Oxygen-Limited BTEX-Contaminated Site

“…The copy number of mRNA transcripts was 4.16 × 10 8 copies mL –1 groundwater in sample ST5 and 1.77 × 10 8 copies mL –1 groundwater in sample ST2. These copy numbers are considerably high, but at the same time, it has to be noted that comparable C23O gene copy numbers were already reported by other studies. − The detected transcript amounts assume high subfamily I.2.C C23O enzyme activity in both groundwater samples; consequently, it can be hypothesized that these enzymes play a substantial role in the degradation of the aromatic contaminants.…”