Search results for "quantitative"

Unraveling the Composition of Insecticidal Crystal Proteins in Bacillus thuringiensis: a Proteomics Approach.

2020

ABSTRACT Bacillus thuringiensis (Bt) is the most widely used active ingredient for biological insecticides. The composition of δ-endotoxins (Cry and Cyt proteins) in the parasporal crystal determines the toxicity profile of each Bt strain. However, a reliable method for their identification and quantification has not been available, due to the high sequence identity of the genes that encode the δ-endotoxins and the toxins themselves. Here, we have developed an accurate and reproducible mass spectrometry-based method (liquid chromatography-tandem mass spectrometry-multiple reaction monitoring [LC-MS/MS-MRM]) using isotopically labeled proteotypic peptides for each protein in a particular mix…

LC–MS Based Cleavage Site Profiling of the Proteases ADAM10 and ADAM17 Using Proteome-Derived Peptide Libraries

2014

A Disintegrin and Metalloproteinase 10 (ADAM10) and ADAM17 catalyze ectodomain shedding of a number of cell surface proteins important for embryonic development and tissue homeostasis. Changes in the expression levels or dysregulated proteolytic activity of ADAM10 and ADAM17 have been shown to play important roles in multiple diseases such as inflammation, cancer, and neurodegenerative disorders. Despite the well documented substrate repertoire of ADAM10 and ADAM17, little is known about their cleavage site specificity. We optimized Q-PICS (Quantitative Proteomics for the Identification of Cleavage Sites) to elucidate the cleavage site specificity of recombinant murine ADAM10 and ADAM17. Tw…

General Statistical Framework for Quantitative Proteomics by Stable Isotope Labeling

2014

Pedro J. Navarro et al.

200 TEST/RETEST- AND INTEROBSERVER-RELIABILITIY IN QUANTITATIVE SENSORY TESTING ACCORDING TO THE PROTOCOL OF THE GERMAN NETWORK ON NEUROPATHIC PAIN (…

2007

Influence of structure on the polarizability of hydrated methane sulfonic acid clusters

2015

Abstract: The relationship between polarizability and structure is investigated in methane sulfonic acid (MSA) and in 36 hydrated MSA clusters. The polarizabilities are calculated at B3LYP and MP2 level and further partitioned into molecular contributions using classic and iterative Hirshfeld methods. The differences in the two approaches for partitioning of polarizabilities are thoroughly analyzed. The polarizabilities of the molecules are found to be influenced in a systematic way by the hydrogen bond network in the clusters, proton transfer between MSA and water molecules, and weak interactions between water molecules and the methyl group of MSA.

The ins and outs of proton complexation

2009

Proton complexation differs from simple protonation by the fact that the coordinated hydrogen atom is bound intramolecularly to more than one donor atom. This is usually achieved by covalent bonding supplemented by hydrogen bonding. In a few cases, however, the complexed proton is hydrogen-bound to all donor atoms, which gives rise to single well (SWHB) and low barrier (LBHB) hydrogen bonds. This tutorial review highlights a full range of proton complexes formed with chelating and "proton-sponge"-type ligands, cryptand-like macropolycycles, and molecules of topological relevance, such as rotaxanes and catenanes. The concept of proton complexation can explain how the smallest cation possible…

Charge-Neutral Constant pH Molecular Dynamics Simulations Using a Parsimonious Proton Buffer

2016

In constant pH molecular dynamics simulations, the protonation states of titratable sites can respond to changes of the pH and of their electrostatic environment. Consequently, the number of protons bound to the biomolecule, and therefore the overall charge of the system, fluctuates during the simulation. To avoid artifacts associated with a non-neutral simulation system, we introduce an approach to maintain neutrality of the simulation box in constant pH molecular dynamics simulations, while maintaining an accurate description of all protonation fluctuations. Specifically, we introduce a proton buffer that, like a buffer in experiment, can exchange protons with the biomolecule enabling its…

Measure of Psychological Variables in Dancers Sport

2012

El objetivo fundamental del estudio consiste en identificar y evaluar las principales variables psicológicas que están interviniendo en los distintos niveles de rendimiento en la práctica de baile deportivo. Para esto, entre otros, se utilizó el Cuestionario de Características Psicológicas aplicadas al Rendimiento Deportivo (Gimeno, Buceta & Pérez-Llantada, 2001). Se realizó un análisis de varianza, y pese a no alcanzar las diferencias valores estadísticamente significativos en los factores Control del Estrés e Influencia de la Evaluación del Rendimiento, sí se puede señalar la existencia de diferencias relevantes en función de la interacción de dos condiciones: el nivel competitivo y el éx…

Statistical properties of the site-frequency spectrum associated with lambda-coalescents.

2013

Abstract Statistical properties of the site-frequency spectrum associated with Λ-coalescents are our objects of study. In particular, we derive recursions for the expected value, variance, and covariance of the spectrum, extending earlier results of Fu (1995) for the classical Kingman coalescent. Estimating coalescent parameters introduced by certain Λ-coalescents for data sets too large for full-likelihood methods is our focus. The recursions for the expected values we obtain can be used to find the parameter values that give the best fit to the observed frequency spectrum. The expected values are also used to approximate the probability a (derived) mutation arises on a branch subtending a…

Parental communication and feelings of affiliation in adolescent aggressors and victims of cyberbullying

2018

Cyberbullying is an increasingly frequent problem among adolescents, and it produces considerable social concern. Using a cross-sectional and quantitative methodology, the main objective of this study was to analyze the differences among students involved in the perpetration and victimization of cyberbullying (non-involved, occasional, and severe), in their parental communication, and feelings of affiliation with classmates. The sample consisted of 849 adolescents (51.7% boys and 48.3% girls) from 12 to 18 years old (M = 14.5