Determination of the [15N]-Nitrate/[14N]-Nitrate Ratio in Plant Feeding Studies by GC⁻MS.

ABSTRACT: Feeding experiments with stable isotopes are helpful tools for investigation of metabolic fluxes and biochemical pathways. For assessing nitrogen metabolism, the heavier nitrogen isotope, [15N], has been frequently used. In plants, it is usually applied in form of [15N]-nitrate, which is assimilated mainly in leaves. Thus, methods for quantification of the [15N]-nitrate/[14N]-nitrate ratio in leaves are useful for the planning and evaluation of feeding and pulse-chase experiments. Here we describe a simple and sensitive method for determining the [15N]-nitrate to [14N]-nitrate ratio in leaves. Leaf discs (8 mm diameter, approximately 10 mg fresh weight) were sufficient for analysis, allowing a single leaf to be sampled multiple times. Nitrate was extracted with hot water and derivatized wi

SUBMITTER: Schramm S 

PROVIDER: S-EPMC6515077 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature