Carbon availability affects already large species-specific differences in chemical composition of ectomycorrhizal fungal mycelia in pure culture

Although ectomycorrhizal (ECM) contribution to soil organic matter processes receives increased attention, little is known about fundamental differences in chemical composition among species, and how that may be affected by carbon (C) availability. Here we study how 16 species (incl. 19 isolates) grown in pure culture at three different C:N ratios (10:1, 20:1 and 40:1) vary in chemical structure, using Fourier transform infrared (FTIR) spectroscopy. We hypothesised that C availability impacts directly on chemical composition, expecting increased C availability to lead to more carbohydrates and less proteins in the mycelia. There were strong and significant effects of ECM species (R2 = 0.873 and P = 0.001) and large species-specific differences in chemical composition. Chemical composition also changed significantly with C availability, and increased C led to more polysaccharides and less proteins for many species, but not all. Understanding how chemical composition change with altered C..., Spectral characterisation of fungal samples was performed by FTIR spectroscopy. Ectomycorrhizal (ECM) fungal isolates (a total of 19 fungal isolates, covering 16 different ECM species) were grown in duplicates in liquid pure culture at 25° C for three weeks at three different C:N ratios (10:1, 20:1 and 40:1), in effect moving from conditions of C limitation (C:N 10:1) to conditions of N limitation (C:N 40:1). At harvest, mycelia were washed in double distilled H2O, freezedried and homogenised. IR spectra were recorded on a Bruker Vertex 70 FTIR spectrometer (Bruker, Ettlingen, Germany) fitted with a potassium bromide beam splitter and a deutroglycine sulphate detector for two replicates of each species. A Diamond Attenuated Total Reflectance (DATR) sampling accessory, with a single reflectance system, was used to produce “transmission-like” spectra, then the IR transmittance spectra were converted to absorbance spectra. Samples were placed directly on a DATR/KRS-5 crystal, and a flat ti..., , # Title of Dataset:

Carbon availability affects already large species-specific differences in chemical composition of ectomycorrhizal fungal mycelia in pure culture
Abstract
Although ectomycorrhizal (ECM) contribution to soil organic matter processes receives increased attention, little is known about fundamental differences in chemical composition among species, and how that may be affected by carbon (C) availability. Here we study how 16 species (incl. 19 isolates) grown in pure culture at three different C:N ratios (10:1, 20:1 and 40:1) vary in chemical structure, using Fourier transform infrared (FTIR) spectroscopy. We hypothesised that C availability impacts directly on chemical composition, expecting increased C availability to lead to more carbohydrates and less proteins in the mycelia. There were strong and significant effects of ECM species (R2 = 0.873 and P = 0.001) and large species-specific differences in chemical composition. Chemical composition also changed significantly...