Details
| Original language | English |
|---|---|
| Pages (from-to) | 6205-6214 |
| Number of pages | 10 |
| Journal | Applied and Environmental Microbiology |
| Volume | 76 |
| Issue number | 18 |
| Publication status | Published - Sept 2010 |
| Externally published | Yes |
Abstract
The earthworm gut is an anoxic nitrous oxide (N2O)-emitting microzone in aerated soils. In situ conditions of the gut might stimulate ingested nitrate-reducing soil bacteria linked to this emission. The objective of this study was to determine if dissimilatory nitrate reducers and denitrifiers in the alimentary canal were affected by feeding guilds (epigeic [Lumbricus rubellus], anecic [Lumbricus terrestris], and endogeic [Aporrectodea caliginosa]). Genes and gene transcripts of narG (encodes a subunit of nitrate reductase and targets both dissimilatory nitrate reducers and denitrifiers) and nosZ (encodes a subunit of N2O reductase and targets denitrifiers) were detected in guts and soils. Gut-derived sequences were similar to those of cultured and uncultured soil bacteria and to soil-derived sequences obtained in this study. Gut-derived narG sequences and narG terminal restriction fragments (TRFs) were affiliated mainly with Gram-positive organisms (Actinobacteria). The majority of gut- and uppermost-soil-derived narG transcripts were affiliated with Mycobacterium (Actinobacteria). In contrast, narG sequences indicative of Gram-negative organisms (Proteobacteria) were dominant in mineral soil. Most nosZ sequences and nosZ TRFs were affiliated with Bradyrhizobium (Alphaproteobacteria) and uncultured soil bacteria. TRF profiles indicated that nosZ transcripts were more affected by earthworm feeding guilds than were nosZ genes, whereas narG transcripts were less affected by earthworm feeding guilds than were narG genes. narG and nosZ transcripts were different and less diverse in the earthworm gut than in mineral soil. The collective results indicate that dissimilatory nitrate reducers and denitriflers in the earthworm gut are soil derived and that ingested narG- and nosZ-containing taxa were not uniformly stimulated in the guts of worms from different feeding guilds.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Biotechnology
- Agricultural and Biological Sciences(all)
- Food Science
- Immunology and Microbiology(all)
- Applied Microbiology and Biotechnology
- Environmental Science(all)
- Ecology
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In: Applied and Environmental Microbiology, Vol. 76, No. 18, 09.2010, p. 6205-6214.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Effect of earthworm feeding guilds on ingested dissimilatory nitrate reducers and denitrifiers in the alimentary canal of the earthworm
AU - Depkat-Jakob, Peter S.
AU - Hilgarth, Maik
AU - Horn, Marcus A.
AU - Drake, Harold L.
N1 - Copyright: Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2010/9
Y1 - 2010/9
N2 - The earthworm gut is an anoxic nitrous oxide (N2O)-emitting microzone in aerated soils. In situ conditions of the gut might stimulate ingested nitrate-reducing soil bacteria linked to this emission. The objective of this study was to determine if dissimilatory nitrate reducers and denitrifiers in the alimentary canal were affected by feeding guilds (epigeic [Lumbricus rubellus], anecic [Lumbricus terrestris], and endogeic [Aporrectodea caliginosa]). Genes and gene transcripts of narG (encodes a subunit of nitrate reductase and targets both dissimilatory nitrate reducers and denitrifiers) and nosZ (encodes a subunit of N2O reductase and targets denitrifiers) were detected in guts and soils. Gut-derived sequences were similar to those of cultured and uncultured soil bacteria and to soil-derived sequences obtained in this study. Gut-derived narG sequences and narG terminal restriction fragments (TRFs) were affiliated mainly with Gram-positive organisms (Actinobacteria). The majority of gut- and uppermost-soil-derived narG transcripts were affiliated with Mycobacterium (Actinobacteria). In contrast, narG sequences indicative of Gram-negative organisms (Proteobacteria) were dominant in mineral soil. Most nosZ sequences and nosZ TRFs were affiliated with Bradyrhizobium (Alphaproteobacteria) and uncultured soil bacteria. TRF profiles indicated that nosZ transcripts were more affected by earthworm feeding guilds than were nosZ genes, whereas narG transcripts were less affected by earthworm feeding guilds than were narG genes. narG and nosZ transcripts were different and less diverse in the earthworm gut than in mineral soil. The collective results indicate that dissimilatory nitrate reducers and denitriflers in the earthworm gut are soil derived and that ingested narG- and nosZ-containing taxa were not uniformly stimulated in the guts of worms from different feeding guilds.
AB - The earthworm gut is an anoxic nitrous oxide (N2O)-emitting microzone in aerated soils. In situ conditions of the gut might stimulate ingested nitrate-reducing soil bacteria linked to this emission. The objective of this study was to determine if dissimilatory nitrate reducers and denitrifiers in the alimentary canal were affected by feeding guilds (epigeic [Lumbricus rubellus], anecic [Lumbricus terrestris], and endogeic [Aporrectodea caliginosa]). Genes and gene transcripts of narG (encodes a subunit of nitrate reductase and targets both dissimilatory nitrate reducers and denitrifiers) and nosZ (encodes a subunit of N2O reductase and targets denitrifiers) were detected in guts and soils. Gut-derived sequences were similar to those of cultured and uncultured soil bacteria and to soil-derived sequences obtained in this study. Gut-derived narG sequences and narG terminal restriction fragments (TRFs) were affiliated mainly with Gram-positive organisms (Actinobacteria). The majority of gut- and uppermost-soil-derived narG transcripts were affiliated with Mycobacterium (Actinobacteria). In contrast, narG sequences indicative of Gram-negative organisms (Proteobacteria) were dominant in mineral soil. Most nosZ sequences and nosZ TRFs were affiliated with Bradyrhizobium (Alphaproteobacteria) and uncultured soil bacteria. TRF profiles indicated that nosZ transcripts were more affected by earthworm feeding guilds than were nosZ genes, whereas narG transcripts were less affected by earthworm feeding guilds than were narG genes. narG and nosZ transcripts were different and less diverse in the earthworm gut than in mineral soil. The collective results indicate that dissimilatory nitrate reducers and denitriflers in the earthworm gut are soil derived and that ingested narG- and nosZ-containing taxa were not uniformly stimulated in the guts of worms from different feeding guilds.
UR - http://www.scopus.com/inward/record.url?scp=77956859837&partnerID=8YFLogxK
U2 - 10.1128/AEM.01373-10
DO - 10.1128/AEM.01373-10
M3 - Article
C2 - 20656855
AN - SCOPUS:77956859837
VL - 76
SP - 6205
EP - 6214
JO - Applied and Environmental Microbiology
JF - Applied and Environmental Microbiology
SN - 0099-2240
IS - 18
ER -