Wild edible plants have become an attractive variation of the human diet, especially in East Asia, North America, and Oceania. However, their potential in nutrition is only rarely considered in Europe. This study aims to reveal the nutritional and antioxidant potential of mature fern leaves from 13 families grown in Europe. We found that most of the examined fern species displayed a high antioxidant capacity, exceeding 0.5 g Trolox equivalent per gram of extract dry weight in ORAC assay and reaching IC50 values lower than 30 µg·mL-1 in DPPH assay (with the value for Trolox 7 µg·mL-1). Most of the species also appeared to be a good source of carotenoids, especially of lutein (205 µg·g-1 DW on average) and β-carotene (161 µg·g-1 DW on average) when compared to the reference leafy vegetables spinach and rocket. A cytotoxicity test using ovine hepatocytes showed a non-toxicity effect of fern leaf extracts.

• Klíčová slova
• Antioxidant capacity, Carotenoids, Ferns, Lutein, Monilophytes, Nutrition, Phenols,
• MeSH
• antioxidancia chemie   farmakologie   MeSH
• beta-karoten analýza   MeSH
• dieta * MeSH
• hepatocyty účinky léků   MeSH
• jedlé rostliny chemie   MeSH
• kapradiny chemie   MeSH
• karotenoidy analýza   MeSH
• lidé MeSH
• lutein analýza   MeSH
• ovce MeSH
• viabilita buněk účinky léků   MeSH
• zelenina chemie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• antioxidancia MeSH
• beta-karoten MeSH
• karotenoidy MeSH
• lutein MeSH

Lower plant species including some green algae, non-vascular plants (bryophytes) as well as the oldest vascular plants (lycopods) and ferns (monilophytes) possess a unique aldehyde dehydrogenase (ALDH) gene named ALDH21, which is upregulated during dehydration. However, the gene is absent in flowering plants. Here, we show that ALDH21 from the moss Physcomitrella patens codes for a tetrameric NADP+ -dependent succinic semialdehyde dehydrogenase (SSALDH), which converts succinic semialdehyde, an intermediate of the γ-aminobutyric acid (GABA) shunt pathway, into succinate in the cytosol. NAD+ is a very poor coenzyme for ALDH21 unlike for mitochondrial SSALDHs (ALDH5), which are the closest related ALDH members. Structural comparison between the apoform and the coenzyme complex reveal that NADP+ binding induces a conformational change of the loop carrying Arg-228, which seals the NADP+ in the coenzyme cavity via its 2'-phosphate and α-phosphate groups. The crystal structure with the bound product succinate shows that its carboxylate group establishes salt bridges with both Arg-121 and Arg-457, and a hydrogen bond with Tyr-296. While both arginine residues are pre-formed for substrate/product binding, Tyr-296 moves by more than 1 Å. Both R121A and R457A variants are almost inactive, demonstrating a key role of each arginine in catalysis. Our study implies that bryophytes but presumably also some green algae, lycopods and ferns, which carry both ALDH21 and ALDH5 genes, can oxidize SSAL to succinate in both cytosol and mitochondria, indicating a more diverse GABA shunt pathway compared with higher plants carrying only the mitochondrial ALDH5.

• Klíčová slova
• Physcomitrella patens, ALDH21, ALDH5, X-ray crystallography, aldehyde dehydrogenase, site-directed mutagenesis, structure-function, succinic semialdehyde, γ-aminobutyric acid,
• MeSH
• Bryophyta enzymologie   genetika   MeSH
• fylogeneze MeSH
• GABA analogy a deriváty   metabolismus   MeSH
• kapradiny enzymologie   genetika   MeSH
• konformace proteinů MeSH
• kyselina jantarová metabolismus   MeSH
• rostlinné geny genetika   fyziologie   MeSH
• substrátová specifita MeSH
• sukcinátsemialdehyddehydrogenasa genetika   metabolismus   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• GABA MeSH
• kyselina jantarová MeSH
• succinic semialdehyde MeSH Prohlížeč
• sukcinátsemialdehyddehydrogenasa MeSH

The RNA-directed DNA methylation (RdDM) pathway can be divided into three phases: 1) small interfering RNA biogenesis, 2) de novo methylation, and 3) chromatin modification. To determine the degree of conservation of this pathway we searched for key genes among land plants. We used OrthoMCL and the OrthoMCL Viridiplantae database to analyze proteomes of species in bryophytes, lycophytes, monilophytes, gymnosperms, and angiosperms. We also analyzed small RNA size categories and, in two gymnosperms, cytosine methylation in ribosomal DNA. Six proteins were restricted to angiosperms, these being NRPD4/NRPE4, RDM1, DMS3 (defective in meristem silencing 3), SHH1 (SAWADEE homeodomain homolog 1), KTF1, and SUVR2, although we failed to find the latter three proteins in Fritillaria persica, a species with a giant genome. Small RNAs of 24 nt in length were abundant only in angiosperms. Phylogenetic analyses of Dicer-like (DCL) proteins showed that DCL2 was restricted to seed plants, although it was absent in Gnetum gnemon and Welwitschia mirabilis. The data suggest that phases (1) and (2) of the RdDM pathway, described for model angiosperms, evolved with angiosperms. The absence of some features of RdDM in F. persica may be associated with its large genome. Phase (3) is probably the most conserved part of the pathway across land plants. DCL2, involved in virus defense and interaction with the canonical RdDM pathway to facilitate methylation of CHH, is absent outside seed plants. Its absence in G. gnemon, and W. mirabilis coupled with distinctive patterns of CHH methylation, suggest a secondary loss of DCL2 following the divergence of Gnetales.

• Klíčová slova
• DNA methylation, RNA-directed DNA methylation, chromatin modification, evolution, seed plants,
• MeSH
• Arabidopsis genetika   MeSH
• chromatin metabolismus   MeSH
• cykasy genetika   metabolismus   MeSH
• cytosin metabolismus   MeSH
• DNA řízené RNA-polymerasy metabolismus   MeSH
• epigeneze genetická MeSH
• fylogeneze MeSH
• genom rostlinný MeSH
• Magnoliopsida enzymologie   genetika   metabolismus   MeSH
• malá interferující RNA metabolismus   MeSH
• malá nekódující RNA chemie   MeSH
• metylace DNA * MeSH
• metylace MeSH
• ribonukleasa III klasifikace   genetika   MeSH
• RNA rostlin chemie   metabolismus   MeSH
• rostlinné geny * MeSH
• rostlinné proteiny klasifikace   genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chromatin MeSH
• cytosin MeSH
• DNA řízené RNA-polymerasy MeSH
• malá interferující RNA MeSH
• malá nekódující RNA MeSH
• ribonukleasa III MeSH
• RNA rostlin MeSH
• rostlinné proteiny MeSH