Combination of biomolecular and stable isotope techniques to determine the origin of organic matter used by bacterial communities: application to sediment

TY - JOUR

T1 - Combination of biomolecular and stable isotope techniques to determine the origin of organic matter used by bacterial communities: application to sediment

AU - Creach, V.

AU - Lucas, F.

AU - Deleu, C.

AU - Bertru, G.

AU - Mariotti, A.

N1 - Reporting year: 1999 Metis note: 2594; CEME; LV; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs1999/Creach_ea_2594.pdf

PY - 1999

Y1 - 1999

N2 - Natural isotopic composition is a good tool to trace organic matter in ecosystems. Recent studies used a combination of molecular and stable isotope techniques to determine the origin of the organic carbon used by bacteria in the water column. In our study, we show that this procedure can be used for analysis of sediment bacterial communities with few modifications. In the water column, bacterial recovery is done before DNA extraction. In the sediment, we tested qualitatively and quantitatively a direct and indirect extraction of DNA. The direct extraction was the most efficient. It recovered between 3.1 and 15.8 mu g DNA g(-1). dry sediment and the contamination of field samples by eucaryotic DNA was less than 13%. In this preliminary study of the salt marsh ecosystem, the delta(13)C values of DNA (-26 to -24 parts per thousand) recovered from the sediment were close to the delta(13)C values of halophytic plants (-26.4 and -25.3 parts per thousand) showing a relationship between plants and microorganisms, Thus, this procedure can be used to trace the flow of carbon through the sediment microbial biomass and to understand the variation of bacterial activity according to the inputs of allocthonous and autochtonous organic matter. [KEYWORDS: DNA; delta C-13 values; bacteria; sediment Direct extraction; carbon; dna; phytoplankton; purification; probes; bloom; soil; rna]

AB - Natural isotopic composition is a good tool to trace organic matter in ecosystems. Recent studies used a combination of molecular and stable isotope techniques to determine the origin of the organic carbon used by bacteria in the water column. In our study, we show that this procedure can be used for analysis of sediment bacterial communities with few modifications. In the water column, bacterial recovery is done before DNA extraction. In the sediment, we tested qualitatively and quantitatively a direct and indirect extraction of DNA. The direct extraction was the most efficient. It recovered between 3.1 and 15.8 mu g DNA g(-1). dry sediment and the contamination of field samples by eucaryotic DNA was less than 13%. In this preliminary study of the salt marsh ecosystem, the delta(13)C values of DNA (-26 to -24 parts per thousand) recovered from the sediment were close to the delta(13)C values of halophytic plants (-26.4 and -25.3 parts per thousand) showing a relationship between plants and microorganisms, Thus, this procedure can be used to trace the flow of carbon through the sediment microbial biomass and to understand the variation of bacterial activity according to the inputs of allocthonous and autochtonous organic matter. [KEYWORDS: DNA; delta C-13 values; bacteria; sediment Direct extraction; carbon; dna; phytoplankton; purification; probes; bloom; soil; rna]

U2 - 10.1016/S0167-7012(99)00076-7

DO - 10.1016/S0167-7012(99)00076-7

M3 - Article

SN - 0167-7012

VL - 38

SP - 43

EP - 52

JO - Journal of Microbiological Methods

JF - Journal of Microbiological Methods

IS - 1-2

ER -