1. Antifungal activity of storage 2S albumins from seeds of the invasive weed dandelion Taraxacum officinale Wigg
T I Odintsova, E A Rogozhin, I V Sklyar, A K Musolyamov, A M Kudryavtsev, V A Pukhalsky, A N Smirnov, E V Grishin, T A Egorov Protein Pept Lett. 2010 Apr;17(4):522-9. doi: 10.2174/092986610790963591.
In this work, we isolated and characterized novel antifungal proteins from seeds of dandelion (Taraxacum officinale Wigg.). We showed that they are represented by five isoforms, each consisting of two disulphide-bonded large and small subunits. One of them, To-A1 was studied in detail, including N-terminal amino acid sequencing of both subunits, and shown to display sequence homology with the sunflower 2S albumin. Using different assays we demonstrated that dandelion 2S albumins possess inhibitory activity against phytopathogenic fungi and the oomycete Phytophtora infestans at micromolar concentrations with various isoforms differing in their antifungal activity. Thus, 2S albumins of dandelion seeds represent a novel example of storage proteins with defense functions.
2. Discovery of novel antimicrobial peptides with unusual cysteine motifs in dandelion Taraxacum officinale Wigg. flowers
A A Astafieva, E A Rogozhin, T I Odintsova, N V Khadeeva, E V Grishin, Ts A Egorov Peptides. 2012 Aug;36(2):266-71. doi: 10.1016/j.peptides.2012.05.009. Epub 2012 May 26.
Three novel antimicrobial peptides designated ToAMP1, ToAMP2 and ToAMP3 were purified from Taraxacum officinale flowers. Their amino acid sequences were determined. The peptides are cationic and cysteine-rich and consist of 38, 44 and 42 amino acid residues for ToAMP1, ToAMP2 and ToAMP3, respectively. Importantly, according to cysteine motifs, the peptides are representatives of two novel previously unknown families of plant antimicrobial peptides. ToAMP1 and ToAMP2 share high sequence identity and belong to 6-Cys-containing antimicrobial peptides, while ToAMP3 is a member of a distinct 8-Cys family. The peptides were shown to display high antimicrobial activity both against fungal and bacterial pathogens, and therefore represent new promising molecules for biotechnological and medicinal applications.
3. Novel proline-hydroxyproline glycopeptides from the dandelion (Taraxacum officinale Wigg.) flowers: de novo sequencing and biological activity
Alexandra A Astafieva, Atim A Enyenihi, Eugene A Rogozhin, Sergey A Kozlov, Eugene V Grishin, Tatyana I Odintsova, Roman A Zubarev, Tsezi A Egorov Plant Sci. 2015 Sep;238:323-9. doi: 10.1016/j.plantsci.2015.07.002. Epub 2015 Jul 9.
Two novel homologous peptides named ToHyp1 and ToHyp2 that show no similarity to any known proteins were isolated from Taraxacum officinale Wigg. flowers by multidimensional liquid chromatography. Amino acid and mass spectrometry analyses demonstrated that the peptides have unusual structure: they are cysteine-free, proline-hydroxyproline-rich and post-translationally glycosylated by pentoses, with 5 carbohydrates in ToHyp2 and 10 in ToHyp1. The ToHyp2 peptide with a monoisotopic molecular mass of 4350.3Da was completely sequenced by a combination of Edman degradation and de novo sequencing via top down multistage collision induced dissociation (CID) and higher energy dissociation (HCD) tandem mass spectrometry (MS(n)). ToHyp2 consists of 35 amino acids, contains eighteen proline residues, of which 8 prolines are hydroxylated. The peptide displays antifungal activity and inhibits growth of Gram-positive and Gram-negative bacteria. We further showed that carbohydrate moieties have no significant impact on the peptide structure, but are important for antifungal activity although not absolutely necessary. The deglycosylated ToHyp2 peptide was less active against the susceptible fungus Bipolaris sorokiniana than the native peptide. Unique structural features of the ToHyp2 peptide place it into a new family of plant defense peptides. The discovery of ToHyp peptides in T. officinale flowers expands the repertoire of molecules of plant origin with practical applications.
