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The 'Catalogna' chicory ( Cichorium intybus L.) is a typical Italian vegetable cultivated for leaves and stems ('puntarelle'); these latter are novel foods, consumed as fresh or processed, and rapidly moving to global markets. The holistic characterization of stems was carried - out by combining NMR metabolic and RNAseq profiling of 'Galatina' (Gal) and 'Molfettese' (Mol) landraces, grown in Apulia and Lazio, in order to investigat e on the nutritional quality and performance in ex situ cultivation. The content variation of thirty - two compounds was affected by the genotype (G), environment (E) and GxE interaction; PCA explained over 90% of variation, and PC1 and PC2 components neatly discriminated Gal vs Mol based on growth sites and genotypes, respectively. Focusing on carbohydrates and amino acids, the total amount of the former was higher in Gal than Mol in both areas (consistently with predicted sweetness and sensory test), whilst the opposite trend occurred for total amino acid content. The Mol vs Gal gene differential transcription was performed based on a Gal reference transcriptome ; G, E, and GxE effects were found and KEGG analysis showed the enrichment of differentially expre ssed genes within the sucrose and phenylalanine metabolisms, consistently with the metabolic profile variations. Pearson's correlation analyses of gene expression vs metabolite amount variations allowed the selection of gene sets that could explain sugar a nd amino acid content differences between Gal and Mol stems. Overall, these analyses widened knowledge on the pathways that influence nutritive quality traits and pointed at target genes useful for plant breeding.

Contryphans are bioactive peptides, isolated from the venom of marine snails of the genus Conus, which are characterized by the short length of the polypeptide chain and the high degree of unusual post-translational modifications. The cyclization of the polypeptide chain through a single disulphide bond, the presence of two conserved Pro residues, and the epimerization of a Trp/Leu residue confer to Contryphans a stable and well-defined structure in solution, conserved in all members of the family, and tolerant to multiple substitutions. The potential of Contryphans as scaffolds for the design of redox-active (macro) molecules was tested by engineering a copper-binding site on two different variants of the natural peptide Contryphan-Vn. The binding site was designed by computational modeling, and the redesigned peptides were synthesized and characterized by optical, fluorescence, electron spin resonance, and nuclear magnetic resonance spectroscopy. The novel peptides, named Cupryphan and Arg-Cupryphan, bind Cu(2+) ions with a 1:1 stoichiometry and a K(d) in the 100 nM range. Other divalent metals (e.g., Zn(2+) and Mg(2+)) are bound with much lower affinity. In addition, Cupryphans catalyze the dismutation of superoxide anions with an activity comparable to other nonpeptidic superoxide dismutase mimics. We conclude that the Contryphan motif represents a natural robust scaffold which can be engineered to perform different functions, providing additional means for the design of catalytically active mini metalloproteins.

The tender stems (turions) of chicory (Cichorium intybus L. Catalogna group) are widely consumed as fresh or processed food in central and southern Italy. They are also known as 'puntarelle' and considered as elite groceries, cultivated as local varieties in Apulia and Lazio. The project CISIA has developed markers based on metabolic, transcriptional and allelic variations aimed to identity, traceability and valorisation of the Galatina and Molfettese Apulian landraces propagated by local enterprises. A de novo reference transcriptome was assembled using RNA of several organs (borne on young and adult plants of Galatina) and Illumina HiSeq2000 technology. Ca. 170M reads were generated (100bp paired-end) and assembled into 96,514 contigs of 1,168bp average length (N50 = 1,435bp). Among them, 68,260 (70.7%) showed significant similarity (Evalue

Cationic lipodepsipeptides from Pseudomonas spp. have been characterized for their structural and antimicrobial properties. In the present study, the structure of a novel lipodepsipeptide, cormycin A, produced in culture by the tomato pathogen Pseudomonas corrugata was elucidated by combined protein chemistry, mass spectrometry and two-dimensional NMR procedures. Its peptide moiety corresponds to L-Ser-D-Orn-L-Asn-D-Hse-L-His- L-aThr-Z-Dhb-L-Asp(3-OH)-L-Thr(4-Cl) [where Orn represents ornithine, Hse is homoserine, aThr is allo-threonine, Z-Dhb is 2,3- dehydro-2-aminobutanoic acid, Asp(3-OH) is 3-hydroxyaspartic acid and Thr(4-Cl) is 4-chlorothreonine], with the terminal carboxy group closing a macrocyclic ring with the hydroxy group of the N-terminal serine residue. This is, in turn, N-acylated by 3,4-dihydroxy-esadecanoate. In aqueous solution, cormycin A showed a rather compact structure, being derived from an inward orientation of some amino acid side chains and from the ‘hairpinbent’ conformation of the lipid, due to inter-residue interactions involving its terminal part. Cormycin was significantly more active than the other lipodepsipeptides from Pseudomonas spp., as demonstrated by phytotoxicity and antibiosis assays, as well as by red-blood-cell lysis. Differences in biological activity were putatively ascribed to its weak positive net charge at neutral pH. Planar lipid membrane experiments showed step-like current transitions, suggesting that cormycin is able to form pores. This ability was strongly influenced by the phospholipid composition of the membrane and, in particular, by the presence of sterols. All of these findings suggest that cormycin derivatives could find promising applications, either as antifungal compounds for topical use or as post-harvest biocontrol agents.

Sono stati analizzati 273 oli italiani delle stagioni 2009 e 2010. Le analisi IRMS hanno individuato una correlazione tra ?13C, ?18O e latitudine, temperatura e pioggia, valutando anche l'effetto stagionale. I campioni del nord hanno una composizione isotopica più leggera di carbonio e ossigeno, quelli delle isole sono più arricchiti in entrambe le annate. Si sono distinte quattro aree geografiche: nord, isole, sud Tirreno e centro-sud Adriatico. Le analisi NMR hanno definito simili classi geografiche, hanno monitorato l'effetto stagionale e le variabili caratteristiche per ogni regione. Gli oli sardi mostrano una maggiore concentrazione di squalene e acido linoleico, gli oli toscani sono ricchi di terpeni 2 e 1, ? sitosterolo e cere, gli oli calabresi mostrano valori di terpeni 2 e 3 più bassi rispetto agli altri campioni peninsulari. L'effetto stagionale si osserva nella diminuzione della concentrazione delle aldeidi tra il primo e il secondo anno in tutte le regioni tranne la Sicilia. In generale la differenza stagionale si nota per Toscana, Lombardia, Molise, Sicilia e Sardegna. Nel Lazio e nella Puglia la differenza è meno netta. Gli oli della Calabria sono gli unici che non mostrano alcun effetto stagionale. L'effetto delle cultivar è stato studiato da entrambe le tecniche.

The 1H-NMR methodology used in the study of genetically modified (GM) foods is discussed. Transgenic lettuce (Lactuca sativa cv "Luxor") over-expressing the Arabidopsis KNAT1 gene is presented as a case study. Twenty-two water-soluble metabolites (amino acids, organic acids, sugars) present in leaves of conventional and GM lettuce were monitored by NMR and quantified at two developmental stages. The NMR spectra did not reveal any difference in metabolite composition between the GM lettuce and the wild type counterpart. Statistical analyses of metabolite variables highlighted metabolism variation as a function of leaf development as well as the transgene. A main effect of the transgene was in altering sugar metabolism.