Novel proline-hydroxyproline glycopeptides from the dandelion (Taraxacum officinale Wigg.) flowers: de novo sequencing and biological activity.

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.

A novel antifungal peptide from leaves of the weed Stellaria media L.

A novel peptide named SmAMP3 was isolated from leaves of common chickweed (Stellaria media L.) by a combination of acidic extraction and a single-step reversed-phase HPLC and sequenced. The peptide is basic and cysteine-rich, consists of 35 amino acids, and contains three disulphide bridges.

A novel hairpin-like antimicrobial peptide from barnyard grass (Echinochloa crusgalli L.) seeds: Structure-functional and molecular-genetics characterization.

A novel plant hairpin-like defense polypeptide named EcAMP3 was isolated from latent barnyard grass (Echinochloa crusgalli L.) seeds. The native peptide and its recombinant analogue were characterized.

Novel antifungal α-hairpinin peptide from Stellaria media seeds: structure, biosynthesis, gene structure and evolution.

Plant defense against disease is a complex multistage system involving initial recognition of the invading pathogen, signal transduction and activation of specialized genes. An important role in pathogen deterrence belongs to so-called plant defense peptides, small polypeptide molecules that present antimicrobial properties. Using multidimensional liquid chromatography, we isolated a novel antifungal peptide named Sm-AMP-X (33 residues) from the common chickweed (Stellaria media) seeds.

A novel cysteine-rich antifungal peptide ToAMP4 from Taraxacum officinale Wigg. flowers.

A novel peptide named ToAMP4 was isolated from Taraxacum officinale Wigg. flowers by a combination of acetic acid extraction and different types of chromatography: affinity, size-exclusion, and RP-HPLC. The amino acid sequence of ToAMP4 was determined by automated Edman degradation.

Genes encoding 4-Cys antimicrobial peptides in wheat Triticum kiharae Dorof. et Migush.: multimodular structural organization, instraspecific variability, distribution and role in defence.

A novel family of antifungal peptides was discovered in the wheat Triticum kiharae Dorof. et Migusch. Two members of the family, designated Tk-AMP-X1 and Tk-AMP-X2, were completely sequenced and shown to belong to the α-hairpinin structural family of plant peptides with a characteristic C1XXXC2-X(n)-C3XXXC4 motif.

Buckwheat trypsin inhibitor with helical hairpin structure belongs to a new family of plant defence peptides.

A new peptide trypsin inhibitor named BWI-2c was obtained from buckwheat (Fagopyrum esculentum) seeds by sequential affinity, ion exchange and reversed-phase chromatography. The peptide was sequenced and found to contain 41 amino acid residues, with four cysteine residues involved in two intramolecular disulfide bonds. Recombinant BWI-2c identical to the natural peptide was produced in Escherichia coli in a form of a cleavable fusion with thioredoxin.

Genes encoding hevein-like defense peptides in wheat: distribution, evolution, and role in stress response.

Hevein-like plant defense peptides WAMP-1a/b with a unique 10-Cys motif are found in the wheat Triticum kiharae seeds. Three different wamp genomic and cDNA sequences were derived from T. kiharae; no introns were spotted in the protein-coding regions of the genes.

Transformation of tobacco and Arabidopsis plants with Stellaria media genes encoding novel hevein-like peptides increases their resistance to fungal pathogens.

Two novel antifungal hevein-like peptides, SmAMP1.1a and SmAMP2.2a, were previously isolated from seeds of Stellaria media.

Solution structure of a defense peptide from wheat with a 10-cysteine motif.

Hevein, a well-studied lectin from the rubber tree Hevea brasiliensis, is the title representative of a broad family of chitin-binding polypeptides. WAMP-1a, a peptide isolated from the wheat Triticum kiharae, shares considerable similarity with hevein. The peptide possesses antifungal, antibacterial activity and is thought to play an important role in the defense system of wheat.

Disulfide-stabilized helical hairpin structure and activity of a novel antifungal peptide EcAMP1 from seeds of barnyard grass (Echinochloa crus-galli).

This study presents purification, activity characterization, and (1)H NMR study of the novel antifungal peptide EcAMP1 from kernels of barnyard grass Echinochloa crus-galli. The peptide adopts a disulfide-stabilized α-helical hairpin structure in aqueous solution and thus represents a novel fold among naturally occurring antimicrobial peptides. Micromolar concentrations of EcAMP1 were shown to inhibit growth of several fungal phytopathogens.

Novel antifungal defensins from Nigella sativa L. seeds.

From seeds of Nigella sativa L. (Ranunculaceae), an endemic plant of Uzbekistan, two novel defensins named Ns-D1 and Ns-D2, were isolated and sequenced. The peptides differ by a single amino acid residue and show high sequence similarity to Raphanus sativus L.

Isolation, molecular cloning and antimicrobial activity of novel defensins from common chickweed (Stellaria media L.) seeds.

Two novel highly homologous defensins, Sm-AMP-D1 and Sm-AMP-D2, were isolated from seeds of common chickweed Stellaria media L. (family Cariophyllaceae). They show sequence homology to defensins of the Brassicaceae plants and display strong inhibitory activity against phytopathogenic fungi and oomycetes in the micromolar range (IC(50)≤1μM).

Purification and characterization of biologically active peptides from spider venoms.

Spider venoms represent invaluable sources of biologically active compounds suitable for use in life science research and also having a significant potential for biotechnology and therapeutic applications. The methods reported herewith are based on our long experience of spider venom fractionation and peptides purification. We routinely screen new peptides for antimicrobial and insecticidal activities and our detailed protocols are also reported here.

A novel antifungal hevein-type peptide from Triticum kiharae seeds with a unique 10-cysteine motif.

Two forms of a novel antimicrobial peptide (AMP), named WAMP-1a and WAMP-1b, that differ by a single C-terminal amino acid residue and belong to a new structural type of plant AMP were purified from seeds of Triticum kiharae Dorof. et Migusch. Although WAMP-1a and WAMP-1b share similarity with hevein-type peptides, they possess 10 cysteine residues arranged in a unique cysteine motif which is distinct from those described previously for plant AMPs, but is characteristic of the chitin-binding domains of cereal class I chitinases.

Seed defensins of barnyard grass Echinochloa crusgalli (L.) Beauv.

From the annual weed barnyard grass Echinochloa crusgalli (L.) Beauv., two novel defensins Ec-AMP-D1 and Ec-AMP-D2 that differ by a single amino acid substitution were isolated by a combination of different chromatographic procedures.

Analysis of Triticum boeoticum and Triticum urartu seed defensins: To the problem of the origin of polyploid wheat genomes.

The origin of polyploid wheat genomes has been the subject of numerous studies and is the key problem in wheat phylogeny. Different diploid species have been supposed to donate genomes to tetraploid and hexaploid wheat species. To shed light on phylogenetic relationships between the presumable A genome donors and hexaploid wheat species we have applied a new approach: the comparison of defensins from diploid Triticum species, Triticum boeoticum Boiss.

Seed defensins from T. kiharae and related species: genome localization of defensin-encoding genes.

Ten new defensins have been isolated from seeds of Triticum kiharae and related species of the Triticum and Aegilops genera by a combination of chromatographic procedures including affinity-, size-exclusion, and reversed-phase high-performance liquid chromatography. Nine were completely sequenced and shown to represent a family of closely related peptides with highly conserved amino acid sequences. Analysis of defensin compositions in diploid A-, B-, and D-genome donors to polyploid wheat allowed us for the first time to assign most defensin-encoding genes to particular hexaploid wheat genomes.

Diversity of wheat anti-microbial peptides.

From seeds of Triticum kiharae Dorof. et Migusch., 24 novel anti-microbial peptides were isolated and characterized by a combination of three-step HPLC (affinity, size-exclusion and reversed-phase) with matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and Edman degradation.

Characterization and analysis of posttranslational modifications of the human large cytoplasmic ribosomal subunit proteins by mass spectrometry and Edman sequencing.

The 60S ribosomal proteins were isolated from ribosomes of human placenta and separated by reversed phase HPLC. The fractions obtained were subjected to trypsin and Glu-C digestion and analyzed by mass fingerprinting (MALDI-TOF), MS/MS (ESI), and Edman sequencing. Forty-six large subunit proteins were found, 22 of which showed masses in accordance with the SwissProt database (June 2002) masses (proteins L6, L7, L9, L13, L15, L17, L18, L21, L22, L24, L26, L27, L30, L32, L34, L35, L36, L37, L37A, L38, L39, L41).