Identification of RNA Hydrolysis Products in NaOH-EDTA Extracts using ³¹P NMR Spectroscopy

Abstract

Ribonucleic acid (RNA) is the most abundant form of organic phosphorus (P) in plant and microbial biomass and is therefore expected to be present in materials such as soils, sediments, composts, and manures. Phosphorus-31 nuclear magnetic resonance (³¹P NMR) spectroscopy is increasingly used to characterize organic P in these materials, usually following extraction into a mixture of sodium hydroxide and ethylenediaminetetraacetic acid (NaOH-EDTA). Under these alkaline conditions, RNA is hydrolysed, providing a distinctive pattern or “fingerprint” in the ³¹P NMR spectrum. Complete assignment of the eight ribonucleotides produced was achieved using a spiking approach. The near coincidence in chemical shift of β-glycerophosphate and two of the ribonucleotide peaks complicates quantification of RNA concentrations when phospholipids are also present, but an approach based on quantifying signal in the most well-separated ribonucleotide peaks is suggested.

Keywords:

• Biochemistry
• nutrient cycling
• phosphorus