TY - JOUR
T1 - Intermediate accumulation of metabolites results in a bottleneck for mineralisation of the herbicide metabolite 2,6-dichlorobenzamide (BAM) by Aminobacter spp.
AU - Simonsen, Allan
AU - Badawi, Nora
AU - Anskjær, Gitte G.
AU - Albers, Christian N.
AU - Sørensen, Sebastian R.
AU - Sørensen, Jan
AU - Aamand, Jens
N1 - Funding Information:
Acknowledgements This work was supported by the Center for Environmental and Agricultural Microbiology, CREAM, funded by the Villum Kann Rasmussen Foundation and by the Research School RECETO. Sebastian R. Sørensen and Christian N. Albers are supported by Microbial Remediation of Contaminated Soil and Water Resources, MIRESOWA, funded by the Danish Council for Strategic Research grant 2104-08-0012. We thank Spire Kiersgaard (GEUS) for skillful assistance with the laboratory work.
PY - 2012/4
Y1 - 2012/4
N2 - Degradation and mineralisation of the groundwater contaminant 2,6-dichloro-benzamide (BAM) was investigated in two Aminobacter strains focussing on the induction of BAM degradation and mineralisation and occurrence of intermediate metabolites. The BAM degradation rate was independent of whether the cells were pre-grown in the absence or presence of BAM, thus indicating that the first step in the degradation pathway was constitutively expressed. In contrast, 14CO2 production was stimulated when cells were pre-grown in the presence of BAM, suggesting that one or more of the subsequent steps in the degradation pathway were inducible. Accumulation of 2,6-dichlorobenzoate (DCBA) during degradation of BAM demonstrated that the first step involved amidase activity. Mass balance calculations and thin-layer chromatography coupled with autoradiographic detection indicated that degradation of DCBA and at least one unknown metabolite may comprise a bottleneck for BAM mineralisation by Aminobacter spp. The study thus provides novel information about the BAM degradation pathway and points to the involvement of unknown intermediate metabolites in degradation of this important groundwater contaminant.
AB - Degradation and mineralisation of the groundwater contaminant 2,6-dichloro-benzamide (BAM) was investigated in two Aminobacter strains focussing on the induction of BAM degradation and mineralisation and occurrence of intermediate metabolites. The BAM degradation rate was independent of whether the cells were pre-grown in the absence or presence of BAM, thus indicating that the first step in the degradation pathway was constitutively expressed. In contrast, 14CO2 production was stimulated when cells were pre-grown in the presence of BAM, suggesting that one or more of the subsequent steps in the degradation pathway were inducible. Accumulation of 2,6-dichlorobenzoate (DCBA) during degradation of BAM demonstrated that the first step involved amidase activity. Mass balance calculations and thin-layer chromatography coupled with autoradiographic detection indicated that degradation of DCBA and at least one unknown metabolite may comprise a bottleneck for BAM mineralisation by Aminobacter spp. The study thus provides novel information about the BAM degradation pathway and points to the involvement of unknown intermediate metabolites in degradation of this important groundwater contaminant.
KW - 2,6-Dichlorobenzamide
KW - 2,6-Dichlorobenzoate
KW - Aminobacter spp.
KW - Metabolites
UR - http://www.scopus.com/inward/record.url?scp=84858449230&partnerID=8YFLogxK
U2 - 10.1007/s00253-011-3591-x
DO - 10.1007/s00253-011-3591-x
M3 - Article
SN - 0175-7598
VL - 94
SP - 237
EP - 245
JO - Applied Microbiology and Biotechnology
JF - Applied Microbiology and Biotechnology
IS - 1
ER -