Nanoremediation and Antioxidant Potential of Biogenic Silver Nanoparticles Synthesized Using Leucena's Leaves, Stem, and Fruits.

Synthetic dyes are persistent organic environmental pollutants that can cause extensive damage to living beings and to the ecosystem as a whole. Cost-effective, sustainable, and efficient strategies to deal with this type of pollution are necessary as it commonly resists conventional water treatment methods. Silver nanoparticles (AgNPs) synthesized using the aqueous extract from the leaves, stem, and fruits of (Leucena) were produced and characterized through UV-vis, TEM, EDS, SDL, XPS, XRD, and zeta potential, and they proved to be able to promote adsorption to remediate methylene blue and tartrazine pollution in water.

Utilising natural diversity of kinases to rationally engineer interactions with the angiosperm immune receptor ZAR1.

The highly conserved angiosperm immune receptor HOPZ-ACTIVATED RESISTANCE1 (ZAR1) recognises the activity of diverse pathogen effector proteins by monitoring the ZED1-related kinase (ZRK) family. Understanding how ZAR1 achieves interaction specificity for ZRKs may allow for the expansion of the ZAR1-kinase recognition repertoire to achieve novel pathogen recognition outside of model species. We took advantage of the natural diversity of Arabidopsis thaliana kinases to probe the ZAR1-kinase interaction interface and found that A.

A Mass Spectrometry-Based Method of Quantifying the Contribution of the Lysine Polymorphism at Position 171 in Sheep PrP.

In sheep, the transmissibility and progression of scrapie, a sheep prion (PrP) disease, is strongly dependent upon specific amino acid polymorphisms in the natively expressed prion protein (PrP). Sheep expressing PrP with lysine (K) polymorphism at position 171 (K171) are partially resistant to oronasal dosing of classical sheep scrapie. In addition, scrapie infected sheep expressing the K171 polymorphism show a longer incubation period compared to sheep homozygous (glutamine (Q)) at position 171.

General Method of Quantifying the Extent of Methionine Oxidation in the Prion Protein.

The normal cellular prion protein (PrP) and its infectious conformer, PrP, possess a disproportionately greater amount of methionines than would be expected for a typical mammalian protein. The thioether of methionine can be readily oxidized to the corresponding sulfoxide, which means that oxidation of methionine can be used to map the surface of the conformation of PrP or PrP, as covalent changes are retained after denaturation. We identified a set of peptides (TNK, LGSASR, LLGSASR, PIHFGNDWEDR, ENNR, ENYR, IER, ER, IER, VVEQCVTQYQK, and VVEQCITQYQR) that contains every methionine in sheep, cervid, mouse, and bank vole PrP.

Chronic Wasting Disease (CWD) in Cervids and the Consequences of a Mutable Protein Conformation.

Chronic wasting disease (CWD) is a prion disease of cervids (deer, elk, moose, etc.). It spreads readily from CWD-contaminated environments and among wild cervids.

Detecting Differences in Prion Protein Conformation by Quantifying Methionine Oxidation.

A prion's pathogenic character is enciphered in its conformation, which also defines the chemical environments of its amino acids. Differences in chemical environments influence the reactivity of amino acid side chains, in a conformation-dependent manner. Chemical oxidation of susceptible methionines would identify those methionines on the surface of a prion, which would reveal conformation-dependent information.

Cellular Prion Protein Mediates α-Synuclein Uptake, Localization, and Toxicity In Vitro and In Vivo.

Background: The cellular prion protein (PrP ) is a membrane-bound, multifunctional protein mainly expressed in neuronal tissues. Recent studies indicate that the native trafficking of PrP can be misused to internalize misfolded amyloid beta and α-synuclein (aSyn) oligomers.

Objectives: We define PrP 's role in internalizing misfolded aSyn in α-synucleinopathies and identify further involved proteins.

Time of Detection of Prions in the Brain by Nanoscale Liquid Chromatography Coupled to Tandem Mass Spectrometry Is Comparable to Animal Bioassay.

Prions cause transmissible and inevitably fatal neurological diseases in agriculturally important animals, including bovine spongiform encephalopathy in domestic cattle, scrapie in sheep and goats, and chronic wasting disease in cervids. Because animals are largely asymptomatic throughout the course of the disease, early detection of prion disease is important. Hamsters were peripherally (ip) inoculated with hamster-adapted (Sc237) prions.

Quantifying the Role of Lysine in Prion Replication by Nano-LC Mass Spectrometry and Bioassay.

Prions propagate by a template driven process, inducing the normal cellular isoform (PrP) to adopt the prion (PrP) conformation. In PrP, the positions of lysines are highly conserved and strongly influence prion propagation. In this study, covalent modification was used to quantitate the role of lysines in the PrP template that drives prion replication.

Benefits of a Hearing Registry: Cochlear Implant Candidacy in Quiet Versus Noise in 1,611 Patients.

Purpose This retrospective study used a cochlear implant registry to determine how performing speech recognition candidacy testing in quiet versus noise influenced patient selection, speech recognition, and self-report outcomes. Method Database queries identified 1,611 cochlear implant recipients who were divided into three implant candidacy qualifying groups based on preoperative speech perception scores (≤ 40% correct) on the AzBio sentence test: quiet qualifying group, +10 dB SNR qualifying group, and +5 dB SNR qualifying group. These groups were evaluated for demographic and preoperative hearing characteristics.

A General Mass Spectrometry-Based Method of Quantitating Prion Polymorphisms from Heterozygous Chronic Wasting Disease-Infected Cervids.

Chronic wasting disease (CWD) is the only prion disease naturally transmitted among farmed and free-ranging cervids (deer, elk, moose, etc.). These diseases are always fatal and have long asymptomatic incubation periods.

Draft Genome Sequences of Shiga Toxin-Producing Escherichia coli O157:H7 Strains Recovered from a Major Production Region for Leafy Greens in California.

Shiga toxin-producing O157:H7 is a foodborne pathogen and is responsible for outbreaks of human gastroenteritis. This report documents the draft genome sequences of nine O157:H7 cattle strains, which were identified to be PCR positive for a Shiga toxin gene but displayed different levels of functional toxin activity.

Using Nanospray Liquid Chromatography and Mass Spectrometry to Quantitate Shiga Toxin Production in Environmental Escherichia coli Recovered from a Major Produce Production Region in California.

A set of 45 environmental strains of Shiga toxin producing Escherichia coli (STEC) from three California counties were analyzed for Shiga toxin production by nanospray liquid chromatography-mass spectrometry and Vero cell bioassay. The STEC in this set comprised six serotypes ((O113:H21, O121:H19, O157:H7, O6:H34, O177:H25, and O185:H7) each containing either the stx or stx operon. Six of the seven O113:H21 were found to contain two distinct stx operons.

Food Forensics: Using Mass Spectrometry To Detect Foodborne Protein Contaminants, as Exemplified by Shiga Toxin Variants and Prion Strains.

Food forensicists need a variety of tools to detect the many possible food contaminants. As a result of its analytical flexibility, mass spectrometry is one of those tools. Use of the multiple reaction monitoring (MRM) method expands its use to quantitation as well as detection of infectious proteins (prions) and protein toxins, such as Shiga toxins.

Recombinant PrPSc shares structural features with brain-derived PrPSc: Insights from limited proteolysis.

Very solid evidence suggests that the core of full length PrPSc is a 4-rung β-solenoid, and that individual PrPSc subunits stack to form amyloid fibers. We recently used limited proteolysis to map the β-strands and connecting loops that make up the PrPSc solenoid. Using high resolution SDS-PAGE followed by epitope analysis, and mass spectrometry, we identified positions ~116/118, 133-134, 141, 152-153, 162, 169 and 179 (murine numbering) as Proteinase K (PK) cleavage sites in PrPSc.

An Improved Method for the Sensitive Detection of Shiga Toxin 2 in Human Serum.

Shiga toxins (Stx) released by Stx-producing (STEC) are virulence factors that are most closely 3associated with hemolytic uremic syndrome (HUS), a life-threatening complication of intestinal infections by STEC. Stx have to enter into the circulatory system before they are delivered to target organs and cause damage. The presence of Stx in sera could be a risk indicator for HUS development.

Determining the Relative Susceptibility of Four Prion Protein Genotypes to Atypical Scrapie.

Atypical scrapie is a sheep prion (PrP) disease whose epidemiology is consistent with a sporadic origin and is associated with specific polymorphisms of the normal cellular prion protein (PrP). To determine the relative amounts of PrP polymorphisms present in atypical scrapie, total PrP was digested with chymotrypsin to generate characteristic peptides spanning relevant polymorphisms at positions 136, 141, 154, 171, and 172 of sheep PrP. A multiple reaction monitoring method (MRM), employing N-labeled internal standards, was used to detect and quantify these polymorphisms present in both the PrP and PrP from heterozygous (ALRRY and ALHQY or ALRQD or AFRQY) atypical scrapie-infected or uninfected control sheep.

Quantitating PrP Polymorphisms Present in Prions from Heterozygous Scrapie-Infected Sheep.

Scrapie is a prion (PrP) disease of sheep. The incubation period of sheep scrapie is strongly influenced by polymorphisms at positions 136, 154, and 171 of a sheep's normal cellular prion protein (PrP). Chymotrypsin was used to digest sheep recombinant PrP to identify a set of characteristic peptides [MLGSXMSRPL (X = A or V), YXENMY (X,= H or R), and YRPVDXY (X = H, K, Q, or R)] that could be used to detect and quantitate polymorphisms at positions 136, 154, and 171 of sheep PrP or PrP.

Identification of new molecular alterations in fatal familial insomnia.

Fatal familial insomnia is a rare disease caused by a D178N mutation in combination with methionine (Met) at codon 129 in the mutated allele of PRNP (D178N-129M haplotype). FFI is manifested by sleep disturbances with insomnia, autonomic disorders and spontaneous and evoked myoclonus, among other symptoms. This study describes new neuropathological and biochemical observations in a series of eight patients with FFI.

Covalent Surface Modification of Prions: A Mass Spectrometry-Based Means of Detecting Distinctive Structural Features of Prion Strains.

Prions (PrP(Sc)) are molecular pathogens that are able to convert the isosequential normal cellular prion protein (PrP(C)) into a prion. The only demonstrated difference between PrP(C) and PrP(Sc) is conformational: they are isoforms. A given host can be infected by more than one kind or strain of prion.

Mass Spectrometry-Based Method of Detecting and Distinguishing Type 1 and Type 2 Shiga-Like Toxins in Human Serum.

Shiga-like toxins (verotoxins) are responsible for the virulence associated with a variety of foodborne bacterial pathogens. Direct detection of toxins requires a specific and sensitive technique. In this study, we describe a mass spectrometry-based method of analyzing the tryptic decapeptides derived from the non-toxic B subunits.

Proteinase K and the structure of PrPSc: The good, the bad and the ugly.

Infectious proteins (prions) are, ironically, defined by their resistance to proteolytic digestion. A defining characteristic of the transmissible isoform of the prion protein (PrP(Sc)) is its partial resistance to proteinase K (PK) digestion. Diagnosis of prion disease typically relies upon immunodetection of PK-digested PrP(Sc) by Western blot, ELISA or immunohistochemical detection.

Behavioral abnormalities in prion protein knockout mice and the potential relevance of PrP(C) for the cytoskeleton.

The cellular prion protein (PrP(C)) is a highly conserved protein, which is anchored to the outer surface of the plasma membrane. Even though its physiological function has already been investigated in different cell or mouse models where PrP(C) expression is either upregulated or depleted, its exact physiological role in a mammalian organism remains elusive. Recent studies indicate that PrP(C) has multiple functions and is involved in cognition, learning, anxiety, locomotion, depression, offensive aggression and nest building behavior.

Safe and effective means of detecting and quantitating Shiga-like toxins in attomole amounts.

Shiga-like toxins (verotoxins) are a class of AB5 holotoxins that are primarily responsible for the virulence associated with Shiga-like toxin producing Escherichia coli (STEC) infections. The holotoxins are composed of a pentamer of identical subunits (B subunit) responsible for delivering the catalytic subunit (A subunit) to a host cell and facilitating endocytosis of the toxin into the cell. The B subunits are not associated with toxicity.