Search results for "SPECT"
showing 10 items of 28650 documents
Phosphinotripeptidic Inhibitors of Leucylaminopeptidases
2021
Phosphinate pseudopeptide are analogs of peptides containing phosphinate moiety in a place of the amide bond. Due to this, the organophosphorus fragment resembles the tetrahedral transition state of the amide bond hydrolysis. Additionally, it is also capable of coordinating metal ions, for example, zinc or magnesium ions. These two properties of phosphinate pseudopeptides make them an ideal candidate for metal-related protease inhibitors. This research investigates the influence of additional residue in the P2 position on the inhibitory properties of phosphinopeptides. The synthetic strategy is proposed, based on retrosynthetic analysis. The N-C-P bond formation in the desired compounds is …
The Odorant-Binding Proteins of the Spider Mite Tetranychus urticae
2021
Spider mites are one of the major agricultural pests, feeding on a large variety of plants. As a contribution to understanding chemical communication in these arthropods, we have characterized a recently discovered class of odorant-binding proteins (OBPs) in Tetranychus urticae. As in other species of Chelicerata, the four OBPs of T. urticae contain six conserved cysteines paired in a pattern (C1–C6, C2–C3, C4–C5) differing from that of insect counterparts (C1–C3, C2–C5, C4–C6). Proteomic analysis uncovered a second family of OBPs, including twelve members that are likely to be unique to T. urticae. A three-dimensional model of TurtOBP1, built on the recent X-ray structure of Varroa destruc…
An Arabidopsis Mutant Over-Expressing Subtilase SBT4.13 Uncovers the Role of Oxidative Stress in the Inhibition of Growth by Intracellular Acidificat…
2020
Intracellular acid stress inhibits plant growth by unknown mechanisms and it occurs in acidic soils and as consequence of other stresses. In order to identify mechanisms of acid toxicity, we screened activation-tagging lines of Arabidopsis thaliana for tolerance to intracellular acidification induced by organic acids. A dominant mutant, sbt4.13-1D, was isolated twice and shown to over-express subtilase SBT4.13, a protease secreted into endoplasmic reticulum. Activity measurements and immuno-detection indicate that the mutant contains less plasma membrane H+-ATPase (PMA) than wild type, explaining the small size, electrical depolarization and decreased cytosolic pH of the mutant but not orga…
X!TandemPipeline: a tool to manage sequence redundancy for protein inference and phosphosite identification
2017
X!TandemPipeline is a software designed to perform protein inference and to manage redundancy in the results of phosphosite identification by database search. It provides the minimal list of proteins or phosphosites that are present in a set of samples using grouping algorithms based on the principle of parsimony. Regarding proteins, a two-level classification is performed, where groups gather proteins sharing at least one peptide and subgroups gather proteins that are not distinguishable according to the identified peptides. Regarding phosphosites, an innovative approach based on the concept of phosphoisland is used to gather overlapping phosphopeptides. The graphical interface of X!Tandem…
Proposal of a Citrus translational genomic approach for early and infield detection of Flavescence dorée in Vitis
2014
Flavescence dore´e (FD) is one of the most widely known grapevine yellows disease and one of the most unabated worldwide in the viticulture sector. In this paper, we outline a strategy for developing an integrated system of technologies to enable rapid, early disease FD detection and diagnosis. We propose the deployment of a newly developed sensor device, the differential mobility spectrometer (DMS), which has shown positive results with a similar vector-borne disease in Citrus. We have previously demonstrated that the gas chromatograph DMS (GC/DMS) can distinguish various citrus diseases, and the system may also allow detection of volatile organic compound (VOC) signals from a tree of othe…
What has been thought and taught on the lunar influence on plants in agriculture? Perspective from physics and biology
2020
This paper reviews the beliefs which drive some agricultural sectors to consider the lunar influence as either a stress or a beneficial factor when it comes to organizing their tasks. To address the link between lunar phases and agriculture from a scientific perspective, we conducted a review of textbooks and monographs used to teach agronomy, botany, horticulture and plant physiology; we also consider the physics that address the e ects of the Moon on our planet. Finally, we review the scientific literature on plant development, specifically searching for any direct or indirect reference to the influence of the Moon on plant physiology. We found that there is no reliable, science-based evi…
Boolean computation in plants using post-translational genetic control and a visual output signal
2018
[EN] Due to autotrophic growing capacity and extremely rich secondary metabolism, plants should be preferred targets of synthetic biology. However, developments in plants usually run below those in other taxonomic groups. In this work we engineered genetic circuits capable of logic YES, OR and AND Boolean computation in plant tissues with a visual output signal. The circuits, which are deployed by means of Agrobacterium tumefaciens, perform with the conditional activity of the MYB transcription factor Roseal from Antirrhinum majus inducing the accumulation of anthocyanins, plant endogenous pigments that are directly visible to the naked eye or accurately quantifiable by spectrophotometric a…
An integrated proteomic and metabolomic study to evaluate the effect of nucleus-cytoplasm interaction in a diploid citrus cybrid between sweet orange…
2018
Key message: Our results provide a comprehensive overview how the alloplasmic condition might lead to a significant improvement in citrus plant breeding, developing varieties more adaptable to a wide range of conditions. Abstract: Citrus cybrids resulting from somatic hybridization hold great potential in plant improvement. They represent effective products resulting from the transfer of organelle-encoded traits into cultivated varieties. In these cases, the plant coordinated array of physiological, biochemical, and molecular functions remains the result of integration among different signals, which derive from the compartmentalized genomes of nucleus, plastids and mitochondria. To dissect …
Molecular signatures of silencing suppression degeneracy from a complex RNA virus
2021
As genomic architectures become more complex, they begin to accumulate degenerate and redundant elements. However, analyses of the molecular mechanisms underlying these genetic architecture features remain scarce, especially in compact but sufficiently complex genomes. In the present study, we followed a proteomic approach together with a computational network analysis to reveal molecular signatures of protein function degeneracy from a plant virus (as virus-host protein-protein interactions). We employed affinity purification coupled to mass spectrometry to detect several host factors interacting with two proteins of Citrus tristeza virus (p20 and p25) that are known to function as RNA sil…
The evolution of colour pattern complexity: selection for conspicuousness favours contrasting within-body colour combinations in lizards.
2015
Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patc…