A 1H-NMR-based metabolomic analysis of propolis from Santa Catarina state

16th IUFoST World Congress of Food Science and Technology: Addressing Global Food Security and Wellness through Food Science and TechnologyPropolis is a resinous biomass produced by honeybees from exudates of local flora. It has been used since ancient times in folk medicine and in recent years has been added to foods and beverages to improve health and prevent diseases. The chemical composition of propolis is highly variable and depends on the climate, season, specie of bee, and mainly the local flora visited by bees to collect resin. In order to identify groups of chemical similarity among samples (n=20 autumn, n=16 winter, n=19 spring, n=17 summer) of propolis produced in Santa Catarina (SC) state (southern Brazil - 2010), lyophilized ethanolic extracts (200 mg/ml, EtOH 70%, v/v) were solubilized in MeOD3 (700l) and analyzed by NMR spectroscopy. One-dimensional 1HNMR spectra were acquired at a magnetic field strength of 500,13/125,03 MHz using a Varian Inova 500 MHz equipment and standard conditions of data acquisition. The 1H-NMR peak list data set was processed under MetaboAnalyst 2.0. suite, computing the resonances at 0.80- 12ppm spectral window. Principal Components Analysis (PCA) score scatter plots (PC1 88.2% x PC2 2.2%) clearly demonstrated samples discriminated mainly according to the season of production. These results suggest that not only geographical origin is important for the classification of propolis, but the seasonal effects as well. Since seasons directly influence the flora available from where bees collect resin, the propolis chemical profile can be significantly modified over the seasons even from a same geographical origin.info:eu-repo/semantics/publishedVersio

Genetic diversity analysis among pigeonpea genotypes adapted to South American regions based on microsatellite markers.

The pigeonpea [Cajanus cajan (L) Millspaugh] is one of the most important perennial legume crops utilized in the food, fodder, soil conservation, crop-livestock integrated systems, reclaiming of degraded pastures and symbiotic nitrogen fixation. Microsatellite markers were used to estimate the genetic diversity of 77 pigeonpea genotypes selected from the germplasm collections at Embrapa Cattle-Southeast and, to evaluate their transferability to Phaseolus vulgaris and Vigna unguiculata species. The number of alleles per locus ranged from 2 to12, with an average of 5.1 alleles. The PIC values ranged from 0.11 to 0.80 (average 0.49) and the D values from 0.23 to 0.91 (average 0.58). The averages of observed and expected heterozygosity were 0.25 and 0.47, respectively, showing a deficit in heterozygosity. A model-based Bayesian approach implemented in the software STRUCTURE was used to assign genotypes into clusters. A dendrogram was constructed based on the modified Roger's genetic distances using a neighbor-joining method (NJ). A total of four clusters were assembled by STRUCTURE and a strong tendency of correspondence between the Bayesian clusters in the NJ tree was observed. The genetic distance ranged from 0.09 to 0.62 (average 0.37), showing a low genetic diversity in the pigeonpea genotypes. Transferability of pigeonpea-specific microsatellites revealed a cross-amplification and the presence of polymorphic alleles in P. vulgaris and V. unguiculata

Development of microsatellite markers in Guineagrass (Panicum maximum Jacq.) and their transferability to other tropical forage grass species.

The Guineagrass (Panicum maximum Jacq.) is one of the most important tropical forage grasses, but genetic knowledge and tools regarding this species are still limited. Therefore, 20 novel polymorphic microsatellite markers were developed, validated, and employed in estimating genetic relationships among 25 P. maximum genotypes selected from a Brazilian germplasm collection. In addition, they were tested for cross-species amplification in four other forage grass species. The number of alleles observed for each locus ranged from 4 to 12 (average 6.7). The values of polymorphism information content (PIC) varied from 0.41 to 0.83 (average 0.61) and the discriminating power (D) ranged from 0.53 to 0.98 (average 0.72). Cross-amplification demonstrated the potential transferability of these microsatellites to four tropical forage grass species. Cluster analysis based on the unweighted pair group method revealed three distinct groups: two clusters consisted of P. maximum genotypes and a third cluster, consisted of the other tropical forage grass species. The data demonstrated that the microsatellites developed herein have potential for germplasm characterization and genetic diversity analysis in P. maximum and other forage grass species

Inheritance of growth habit detected by genetic linkage analysis using microsatellites in the common bean (Phaseolus vulgaris L.).

The genetic linkage map for the common bean (Phaseolus vulgaris L.) is a valuable tool for breeding programs. Breeders provide new cultivars that meet the requirements of farmers and consumers, such as seed color, seed size, maturity, and growth habit. A genetic study was conducted to examine the genetics behind certain qualitative traits. Growth habit is usually described as a recessive trait inherited by a single gene, and there is no consensus about the position of the locus. The aim of this study was to develop a new genetic linkage map using genic and genomic microsatellite markers and three morphological traits: growth habit, flower color, and pod tip shape. A mapping population consisting of 380 recombinant F10 lines was generated from IAC-UNA × CAL143. A total of 871 microsatellites were screened for polymorphisms among the parents, and a linkage map was obtained with 198 mapped microsatellites. The total map length was 1865.9 cM, and the average distance between markers was 9.4 cM. Flower color and pod tip shape were mapped and segregated at Mendelian ratios, as expected. The segregation ratio and linkage data analyses indicated that the determinacy growth habit was inherited as two independent and dominant genes, and a genetic model is proposed for this trait

Antibody Complementarity-Determining Regions (CDRs) Can Display Differential Antimicrobial, Antiviral and Antitumor Activities

Background: Complementarity-determining regions (CDRs) are immunoglobulin (Ig) hypervariable domains that determine specific antibody (Ab) binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. the possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here.Methodology/Principal Findings: CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a) a protein epitope of Candida albicans cell wall stress mannoprotein; b) a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c) a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. the inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains.Conclusions/Significance: the high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. the easy production and low cost of small sized synthetic peptides representing Ig CDRs and the possibility of peptide engineering and chemical optimization associated to new delivery mechanisms are expected to give rise to a new generation of therapeutic agents.Department of Education, Universities and Research, Basque GovermentFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Istituto Superiore di Sanita, National Research Project on A.I.D.S.Cariparma Banking FoundationBrazilian National Research CouncilUniv Parma, Sez Microbiol, Dipartimento Patol, I-43100 Parma, ItalyUniv Basque Country, Fac Med Odontol, Dept Inmunol, Microbiol Parasitol, Bilbao, SpainUniv Basque Country, Dept Enfermeria I, Bilbao, SpainUniv Milan, Dipartimento Sci Cliniche L Sacco, Sez Malattie Infettive Immunopatol, Milan, ItalyUniv Studi Parma, Dipartimento Clin Med, Nefrol Sci Prev, Parma, ItalyUniversidade Federal de São Paulo, Departamento Microbiol, Imunol Parasitol, Unidade Oncol Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, São Paulo, BrazilUniversidade Federal de São Paulo, Departamento Microbiol, Imunol Parasitol, Unidade Oncol Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, São Paulo, BrazilDepartment of Education, Universities and Research, Basque Goverment: IT-264-07FAPESP: 06/50634-2Istituto Superiore di Sanita, National Research Project on A.I.D.S.: 50G.30Istituto Superiore di Sanita, National Research Project on A.I.D.S.: 40D.14Cariparma Banking Foundation: 2004.0190Brazilian National Research Council: research fellowshipWeb of Scienc

Lytic Activity and Structural Differences of Amphipathic Peptides Derived from Triatoma infestans Trialysin

Trialysin is a pore-forming protein found in the saliva of Triatoma infestans (Hemiptera, Reduviidae), the insect vector of Chagas' disease. The protein is active against a broad range of cell types from bacteria to eukaryotic cells. Recognizing that the N-terminus of trialysin harbors the lytic motif [Amino, R., Martins, R. M., Procopio, J., Hirata, I.Y., Juliano, M. A., and Schenkman, S. (2002) J. Biol. Chem. 277, 6207-6213], we designed a set of peptides scanning this region to investigate the structural basis of its biological function. Peptides encompassing residues 1-32 (P6), 1-27 (P7), and 6-32 (P5) efficiently induced lysis of the protozoan parasite Trypanosoma cruzi and Escherichia coli in the 0.4-9.0 mu M range, while much higher concentrations were required to cause hemolysis. Other more internal peptides, including peptide P2 (residues 21-47) and others up to residue 52, were less effective. P6 turned out to be the most active of all. P7 has a significantly higher activity than P5 against E. coli, while P5 has a hemolytic activity comparable to that of P6. CD spectroscopy showed that all tested peptides acquire a comparable helical content in solvent mixtures or in detergent micelles. The solution structure of P2 and P5-P7 was determined in a 30% trifluoroethanol/water mixture by nuclear magnetic resonance. All peptides exhibit a structure characterized by a central helical fold, and except for P2, which does not show a continuous hydrophobic surface, they are amphipathic. The structural models show that P5 and P7 extend their structural similarities with the most active peptide, P6, in either the C-terminus or the N-terminus. Amino acid substitutions in the N-terminus of P6 improved hemolysis but did not change the activity against T cruzi. These results suggest that while amphipathicity is essential for the lytic activity, the selectivity of the active peptides for specific organisms appears to be associated with the structural features of their N- and C-termini

Insights on channel selectivity from the structural and functional characterization of the Kv1.3 channel blocker Tc32

The utility of toxins in biomedical research, diagnosis, and therapy is widely recognized. Unfortunately their use is limited by an inadequate target discrimination. Thus, the search for target-specific toxins is of primary relevance. The fact that despite the incredible number of toxins present in the animal kingdom, only a limited number of molecular scaffolds has been selected, is a clear evidence of the importance of the nature and spatial orientation the side chains. The description and understanding of the contact surface between the toxin and the channel entrance appears to be the target for the rationale design of selective and high affinity drugs. Tc32 toxin from the scorpion Tityus cambridgei has been reported to have a clear inhibitory effect on Kv1.3 K channel [1]. This channel, member of the Shaker family [2], carries a large proportion of the outward current not only in leucocytes [3] but also in a variety of neuronal cells [4]. In the present work, Tc32 has been cloned and expressed in a soluble and active form for the first time, employing a new protocol we devised [5]. Tc32 activity has been characterized by electrophysiological assays on a distinct subpopulation of periglomerular cells of olfactory bulb and its 3D solution structure determined by 1HNMR spectroscopy. The structure reveals it exhibits an α/β scaffold typical of the members of the α-KTx family. A structural comparison with the other members of α- KTx 18 subfamily is presented following molecular modeling calculations, and docking simulations to Kv1.1 and Kv1.3 channels. Our data point out Tc32 as a good lead molecule for the development of new molecules suited for research, diagnosis and therapy