Incorporation of α-trifluoromethyl substituted α-amino acids into C-and N-terminal position of peptides and peptide mimetics using multicomponent reactions

Abstract The capacity to assimilate carbon and nitrogen, to transport the resultant sugars and amino acids to sink tissues, and to convert the incoming sugars and amino acids into storage compounds in the sink tissues, are key determinants of crop yield. Given that all of these processes have the potential to co-limit growth, multiple genetic interventions in source and sink tissues, plus transport processes may be necessary to reach the full yield potential of a crop. We used biolistic combinatorial co-transformation (up to 20 transgenes) for increasing C and N flows with the purpose of increasing tomato fruit yield. We observed an increased fruit yield of up to 23%. To better explore the reconfiguration of metabolic networks in these transformants, we generated a dataset encompassing physiological parameters, gene expression and metabolite profiling on plants grown under glasshouse or polytunnel conditions. A Sparse Partial Least Squares regression model was able to explain the combination of genes that contributed to increased fruit yield. This combinatorial study of multiple transgenes targeting primary metabolism thus offers opportunities to probe the genetic basis of metabolic and phenotypic variation, providing insight into the difficulties in choosing the correct combination of targets for engineering increased fruit yield.

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Selected Research Topics of the Dondoni Group over the Last Two Decades (2000–2020)

Synlett ◽

10.1055/s-0040-1707107 ◽

2020 ◽

Vol 31 (14) ◽

pp. 1361-1371 ◽

Cited By ~ 1

Author(s):

Alessandro Dondoni

Keyword(s):

Amino Acids ◽

Bioorganic Chemistry ◽

Multicomponent Reactions ◽

Building Blocks ◽

Synthetic Methods ◽

Research Topics ◽

Main Target ◽

Sulfur Fluoride ◽

Primary Rule ◽

Selection Of

From a selection of research topics carried out in our laboratory during the last twenty years it becomes apparent that our main target was the discovery of new or improved synthetic methods together with new properties. Our efforts were made with the aim of being of some utility to other fields of research, with particular emphasis to glycobiology and heterocyle-based bioorganic chemistry. We performed new chemistry mainly in the field of carbohydrate manipulations taking as a primary rule the simplicity and efficiency manners. Toward this end, modern synthetic tools and approaches were employed such as heterocyle-based transformations, multicomponent reactions, organocatalysis, click azide–alkyne cycloadditions, reactions in ionic liquids, click photoinduced thiol-ene coupling, and click sulfur–fluoride exchange chemistry. With these potent methodologies in hand, the syntheses of carbohydrate containing amino acids up to proteins glycosylation were performed.1 Heterocyclic Glycoconjugates and Amino Acids2 Triazole-Linked Oligonucleotides: Application of Click CuAAC3 Non-Natural Glycosyl Amino Acids4 Non-Natural Oligosaccharides5 Calixarene-Based Glycoclusters6 Carbohydrate-Based Building Blocks7 Homoazasugars and Aza-C-disaccharides8 Synthesis of Glycodendrimers9 Peptide and Protein Glycoconjugates10 Conclusions

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Phyloproteomic Analysis of 11780 Six-Residue-Long Motifs Occurrences

BioMed Research International ◽

10.1155/2015/208346 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

O. V. Galzitskaya ◽

M. Yu. Lobanov

Keyword(s):

Amino Acids ◽

Phylogenetic Relationships ◽

Correlation Coefficients ◽

Terminal Position ◽

Phylogenetic Reconstructions ◽

Eukaryotic Proteomes ◽

Bacterial Proteomes

How is it possible to find good traits for phylogenetic reconstructions? Here, we present a new phyloproteomic criterion that is an occurrence of simple motifs which can be imprints of evolution history. We studied the occurrences of 11780 six-residue-long motifs consisting of two randomly located amino acids in 97 eukaryotic and 25 bacterial proteomes. For all eukaryotic proteomes, with the exception of the Amoebozoa, Stramenopiles, and Diplomonadida kingdoms, the number of proteins containing the motifs from the first group (one of the two amino acids occurs once at the terminal position) made about 20%; in the case of motifs from the second (one of two amino acids occurs one time within the pattern) and third (the two amino acids occur randomly) groups, 30% and 50%, respectively. For bacterial proteomes, this relationship was 10%, 27%, and 63%, respectively. The matrices of correlation coefficients between numbers of proteins where a motif from the set of 11780 motifs appears at least once in 9 kingdoms and 5 phyla of bacteria were calculated. Among the correlation coefficients for eukaryotic proteomes, the correlation between the animal and fungi kingdoms (0.62) is higher than between fungi and plants (0.54). Our study provides support that animals and fungi are sibling kingdoms. Comparison of the frequencies of six-residue-long motifs in different proteomes allows obtaining phylogenetic relationships based on similarities between these frequencies: the Diplomonadida kingdoms are more close to Bacteria than to Eukaryota; Stramenopiles and Amoebozoa are more close to each other than to other kingdoms of Eukaryota.

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Domain assembly of the GLUT1 glucose transporter

Biochemical Journal ◽

10.1042/bj3000291 ◽

1994 ◽

Vol 300 (2) ◽

pp. 291-294 ◽

Cited By ~ 30

Author(s):

D L Cope ◽

G D Holman ◽

S A Baldwin ◽

A J Wolstenholme

Keyword(s):

Amino Acids ◽

Binding Sites ◽

Glucose Transporter ◽

Cytochalasin B ◽

Insect Cells ◽

Full Length ◽

Stable Complex ◽

C And N ◽

Terminal Amino ◽

Glut1 Glucose Transporter

A full-length construct of the glucose transporter isoform GLUT1 has been expressed in Sf9 (Spodoptera frugiperida Clone 9) insect cells, and a photolabelling approach has been used to show that the expressed protein binds the bismannose compound 2-N-4-(1-azi-2,2,2-trifluoroethyl)benzoyl-1,3-bis-(D-mannos- 4-yloxy)-2-propylamine (ATB-BMPA) and cytochalasin B at its exofacial and endofacial binding sites respectively. Constructs of GLUT1 which produce either the N-terminal (amino acids 1-272) or C-terminal (amino acids 254-492) halves are expressed at levels in the plasma membrane which are similar to that of the full-length GLUT1 (approximately 200 pmol/mg of membrane protein), but do not bind either ATB-BMPA or cytochalasin B. When Sf9 cells are doubly infected with virus constructs producing both the C- and N-terminal halves of GLUT1, then the ligand labelling is restored. Only the C-terminal half is labelled, and, therefore, the labelling of this domain is dependent on the presence of the N-terminal half of the protein. These results suggest that the two halves of GLUT1 can assemble to form a stable complex and support the concept of a bilobular structure for the intact glucose transporters in which separate C- and N-domain halves pack together to produce a ligand-binding conformation.

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The enzymic degradation of ovalbumin and its glycopeptides

Biochemical Journal ◽

10.1042/bj1150717 ◽

1969 ◽

Vol 115 (4) ◽

pp. 717-723 ◽

Cited By ~ 16

Author(s):

J. Conchie ◽

A J Hay ◽

I. Strachan ◽

G. A. Levvy

Keyword(s):

Amino Acids ◽

Aspartic Acid ◽

Small Proportion ◽

Carbohydrate Moiety ◽

Side Chain ◽

Terminal Position

1. Ovalbumin glycopeptides, freed from all amino acids other than aspartic acid and a small proportion of leucine by repeated digestion with Pronase, were hydrolysed by 1-aspartamido-β-N-acetylglucosamine amidohydrolase (glycoaspartamidase) to the corresponding oligosaccharides. The glycoaspartamidase did not attack ovalbumin itself. 2. Ovalbumin, with mannose/hexosamine ratio 5:4, lost 1·5moles of N-acetylglucosamine and more than 2moles of mannose after incubation with α-mannosidase and β-N-acetylglucosaminidase respectively. 3. In ovalbumin glycopeptides with approximate mannose/hexosamine ratios 5:3 and 5:4, one and two N-acetylglucosamine residues respectively were accessible to the action of β-N-acetylglucosaminidase. 4. A mixture of α-mannosidase and β-N-acetylglucosaminidase, acting on an ovalbumin glycopeptide with mannose/hexosamine ratio 5:3·7, removed nearly 4moles of mannose and 1·5moles of N-acetylglucosamine. 5. α-Mannosidase removed about 1·5moles of mannose from the ovalbumin oligosaccharide with mannose/hexosamine ratio approx. 5:3. The subsequent action of β-N-acetylglucosaminidase liberated less than 1mole of N-acetylglucosamine and made at least 1mole further of mannose accessible to α-mannosidase action. 6. It is concluded that the carbohydrate moiety of ovalbumin is linked through a glycosyl group to asparagine. In a molecule with mannose/hexosamine ratio 5:4, there are two β-N-acetylglucosamine residues linked together in a terminal position, followed by α-mannose. There is also present a side chain containing two α-mannose units.

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Design and Synthesis of New Classes of Heterocyclic C-Glycoconjugates and Carbon-Linked Sugar and Heterocyclic Amino Acids by Asymmetric Multicomponent Reactions (AMCRs)

ChemInform ◽

10.1002/chin.200641249 ◽

2006 ◽

Vol 37 (41) ◽

Author(s):

Alessandro Dondoni ◽

Alessandro Massi

Keyword(s):

Amino Acids ◽

Multicomponent Reactions ◽

Design And Synthesis

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