Dataset Information

Compound-specific ?¹⁵N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.

ABSTRACT: Haplocladium microphyllum moss samples were collected in Nanchang, China. Free amino acid (FAA) concentrations and N isotope compositions (?¹⁵N_FAA) in the samples were determined and compared with the bulk N concentrations and ?¹⁵N_bulk values. The aim was to determine whether ?¹⁵N_FAA values in moss (which are very variable) indicate the sources of atmospheric N. The ?¹⁵N_FAA values among individual FAA varied widely (from -19.3‰ to +16.1‰), possibly because of the different sources of N and isotope fractionation in amino acids metabolic pathways. Total ¹⁵N-enrichment for the individual FAAs was equal to total ¹⁵N-depletion relative to ?¹⁵N_bulk. The concentration-weighted mean ?¹⁵N value for total FAAs (TFAA) (?¹⁵N_TFAA) was -3.1‰?±?3.2‰, which was similar to ?¹⁵N_bulk (-4.0‰?±?2.9‰). We concluded that a N isotope balance occurred during amino acid metabolism and that little isotope disparity occurred between the concentration-weighted TFAA and bulk N. We concluded that ?¹⁵N_TFAA ? ?¹⁵N_bulk ? ?¹⁵N_source. The mean ?¹⁵N_alanine (-4.1‰), ?¹⁵N_glutamate (-4.2‰), and ?¹⁵N_lysine (-4.0‰) were similar to the mean ?¹⁵N_bulk, which we attributed to little isotope fractionation occurring during their in situ the metabolic pathways. This suggests that ?¹⁵N_alanine, ?¹⁵N_glutamate, and ?¹⁵N_lysine in moss can be used to indicate the sources of atmospheric N deposition.

SUBMITTER: Zhu RG

PROVIDER: S-EPMC6156404 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Compound-specific δ15N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.

Zhu Ren-Guo RG Xiao Hua-Yun HY Zhang Zhongyi Z Lai Yuanyuan Y

Scientific reports 20180925 1

Haplocladium microphyllum moss samples were collected in Nanchang, China. Free amino acid (FAA) concentrations and N isotope compositions (δ15NFAA) in the samples were determined and compared with the bulk N concentrations and δ15Nbulk values. The aim was to determine whether δ15NFAA values in moss (which are very variable) indicate the sources of atmospheric N. The δ15NFAA values among individual FAA varied ...[more]

PMID: 30254224

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Compound-specific ?¹⁵N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.

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Compound-specific δ<sup>15</sup>N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.

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Dataset Information

Compound-specific ?15N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.

Publications

Compound-specific δ<sup>15</sup>N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

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Compound-specific ?¹⁵N composition of free amino acids in moss as indicators of atmospheric nitrogen sources.