Toggle Main Menu Toggle Search

Open Access padlockePrints

Taxon-specific responses of soil bacteria to the addition of low level C inputs

Lookup NU author(s): Dr Sasha Jenkins, Professor Stephen Rushton, Dr Clare Lanyon, Ian Waite, Professor Anthony O'Donnell


Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


The addition of small or trace amounts of carbon to soils can result in the release of 2-5 times more C as CO2 than was added in the original solution. The identity of the microorganisms responsible for these so-called trigger effects remains largely unknown. This paper reports on the response of individual bacterial taxa to the addition of a range of C-14-glucose concentrations (150, 50 and 15 and 0 mu g C g(-1) soil) similar to the low levels of labile C found in soil. Taxon-specific responses were identified using a modification of the stable isotope probing (SIP) protocol and the recovery of [C-14] labelled ribosomal RNA using equilibrium density gradient centrifugation. This provided good resolution of the 'heavy' fractions ([C-14] labelled RNA) from the 'light' fractions ([C-12] unlabelled RNA). The extent of the separation was verified using autoradiography. The addition of [C-14] glucose at all concentrations was characterised by changes in the relative intensity of particular bands. Canonical correspondence analysis (CCA) showed that the rRNA response in both the 'heavy' and 'light' fractions differed according to the concentration of glucose added but was most pronounced in soils amended with 150 mu g C g(-1) soil. In the 'heavy RNA' fractions there was a clear separation between soils amended with 150 mu g C g(-1), soil and those receiving 50 and 15 mu g C g(-1) soil indicating that at low C inputs the microbial community response is quite distinct from that seen at higher concentrations. To investigate these differences further, bands that changed in relative intensity following amendment were excised from the DGGE gels, reamplified and sequenced. Sequence analysis identified 8 taxa that responded to glucose amendment (Bacillus, Pseudomonas, Burkholderia, Bradyrhizobium, Actinobacteria, Nitrosomonas, Acidobacteria and an uncultured beta-proteobacteria). These results show that radioisotope probing (RNA-RIP) can be used successfully to study the fate of labile C substrates, such as glucose, in soil. (C) 2010 Elsevier Ltd. All rights reserved.

Publication metadata

Author(s): Jenkins SN, Rushton SP, Lanyon CV, Whiteley AS, Waite IS, Brookes PC, Kemmitt S, Evershed RP, O'Donnell AG

Publication type: Article

Publication status: Published

Journal: Soil Biology and Biochemistry

Year: 2010

Volume: 42

Issue: 9

Pages: 1624-1631

Print publication date: 19/06/2010

ISSN (print): 0038-0717

ISSN (electronic): 1879-3428

Publisher: Pergamon


DOI: 10.1016/j.soilbio.2010.06.002


Altmetrics provided by Altmetric