Free amino acid regulation in fronds and roots of two Pteris cretica L. ferns under arsenic stress

Zemanová V., Pavlíková D., Pavlík M.

Keywords: amide, metalloid, pyruvate family, serine family, shikimate family, toxicity
Abstract: In the present study, free amino acid (AA) regulation in the arsenic (As) hyperaccumulating ferns was evaluated in a pot experiment to determine the relationship between As stress and the characteristic change in metabolism of AAs. The ferns Pteris cretica cv. Albo-lineata (Pc-Al) and cv. Parkerii (Pc-Pa) were exposed to As treatments at 0, 20, 100, and 250 mg As/kg for 90 days. Greater As content, as well as higher biomass production, were identified in Pc-Al compared with Pc-Pa. Ferns showed changes in the stress metabolism of free AA homeostasis. These results indicate a disturbance in nitrogen metabolism and depletion of pool assimilated carbon metabolism. In the fronds and roots, Pc-Pa accumulated higher amounts of free AAs than Pc-Al. The total free AA content, as well as the ratio of the main AA family pathway (glutamate family), were increased by the accumulation of toxic As in the ferns. Results suggest that Pc-Al tolerates higher As doses better due to changes in AA biosynthesis; however, at higher As doses, Pc-Pa upregulated AA biosynthesis due to As toxicity. The most abundant free AAs of ferns was glutamine, which was enhanced by As. Furthermore, the ratios of selected individual free AAs revealed a characteristic phenotype difference between ferns.
DOI: 10.17221/369/2020-PSE
IEB authors: Milan Pavlík