Search results for "hranila"
showing 7 items of 7 documents
Evolution of the leucine gene cluster in Buchnera aphidicola: insights from chromosomal versions of the cluster.
2004
ABSTRACT In Buchnera aphidicola strains associated with the aphid subfamilies Thelaxinae, Lachninae, Pterocommatinae, and Aphidinae, the four leucine genes ( leuA , - B , - C , and - D ) are located on a plasmid. However, these genes are located on the main chromosome in B. aphidicola strains associated with the subfamilies Pemphiginae and Chaitophorinae. The sequence of the chromosomal fragment containing the leucine cluster and flanking genes has different positions in the chromosome in B. aphidicola strains associated with three tribes of the subfamily Pemphiginae and one tribe of the subfamily Chaitophorinae. Due to the extreme gene order conservation of the B. aphidicola genomes, the v…
Influence of packaging on the aroma stability of strawberry syrup during shelf life
2001
Different types of packaging (glass bottle, PVC, and PET) were compared for the preservation of aroma quality of a strawberry syrup during shelf life. Esters, alcohols, and aldehydes were analyzed by solid-phase micro-extraction (SPME) and solvent extraction. During storage, hydrolysis of esters in acids and alcohols led to a modification of the aroma profile which can be explained by the replacement of “fruity” and “fresh” notes by “dairy note” in the syrup. Aroma compounds that are responsible for fruity notes, such as methyl cinnamate, methyl anthranilate, and methyl dihydrojasmonate, were strongly reduced after 90 days. This could be explained by a selective interaction of these compoun…
Molecular characterization of the leucine cluster in Buchnera PSY, primary endosymbiont of the aphid Pemphigus spyrothecae
2002
ABSTRACT Buchnera strains from most aphid subfamilies studied to date have been found to carry the leucine gene cluster ( leuA , - B , - C , and - D ) on a plasmid, an organization unique among bacteria. Here, however, we demonstrate a classical chromosomal location of the cluster in Buchnera sp. strain PSY from the aphid Pemphigus spyrothecae (subfamily Pemphiginae). The genes that flank leuABCD in Buchnera sp. strain PSY appear to be adjacent in the genome of Buchnera sp. strain APS, a strain carrying a leucine plasmid. We propose that the presence of a leucine plasmid predates the diversification of symbiotic Buchnera and that the chromosomal location observed in Buchnera sp. strain PSY …
Nrf2-interacting nutrients and COVID-19: time for research to develop adaptation strategies
2020
AbstractThere are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of …
Activation of Anthranilate Phosphoribosyltransferase from Sulfolobus solfataricus by Removal of Magnesium Inhibition and Acceleration of Product Rele…
2009
Anthranilate phosphoribosyltransferase from the hyperthermophilic archaeon Sulfolobus solfataricus (ssAnPRT) is encoded by the sstrpD gene and catalyzes the reaction of anthranilate (AA) with a complex of Mg(2+) and 5'-phosphoribosyl-alpha1-pyrophosphate (Mg.PRPP) to N-(5'-phosphoribosyl)-anthranilate (PRA) and pyrophosphate (PP(i)) within tryptophan biosynthesis. The ssAnPRT enzyme is highly thermostable (half-life at 85 degrees C = 35 min) but only marginally active at ambient temperatures (turnover number at 37 degrees C = 0.33 s(-1)). To understand the reason for the poor catalytic proficiency of ssAnPRT, we have isolated from an sstrpD library the activated ssAnPRT-D83G + F149S double …
Plasmid-encoded anthranilate synthase (TrpEG) in Buchnera aphidicola from aphids of the family pemphigidae
1999
Aphids are dependent on an intracellular symbiont (Buchnera aphidicola, Proteobacteria) for normal growth and reproduction (7, 19, 45). The bacteria reside in specialized cells in the aphid hemocele and are transmitted maternally through infection of eggs or embryos (11, 26). Phylogenetic studies have revealed two major characteristics of the evolutionary history of the association (37, 39); (i) the symbiosis had a single origin, dated about 150 million to 250 million years ago; and (ii) host and symbiont lineages have since diverged strictly in parallel. The association, like other symbioses in insects feeding on restricted and unbalanced diets, is thought to have a nutritional basis (5–7,…
Quantitative determination of potent flavor compounds in Burgundy Pinot noir wines using a stable isotope dilution assay
1997
A specific experimental procedure suitable for the quantification of four esters recently identified in a wine of Vitis vinifera cv. Pinot Noir, ethyl dihydrocinnamate (A), ethyl cinnamate (B), methyl anthranilate (C), and ethyl anthranilate (D), was developed and applied to 33 Burgundy wines (calculated on three replicates). The method, involving a stable isotope dilution assay, allows the determination of concentrations from 0.05 μg L-1, with a repeatability better than 10%. The mean, maximum, and minimum amounts found for the four esters were as follows (in μg L-1): (A) 1.6, 3.2, 0.8; (B) 0.8, 1.6, 0.5; (C) 0.2, 0.6, 0.06; (D) 2.4, 4.8, 0.6. Differences between wines, according to their…