Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002736 (amyotrophic lateral sclerosis)
 19,048 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A differential pulse polarographic study of the Cd2+/gamma-Glu-Cys and Cd2+/Cys-Gly systems assisted by the alternating least-squares multivariate curve resolution (MCR-ALS) method was carried out to obtain a better understanding of the different metal affinities of the complexation sites on glutathione (GSH). The simultaneous analysis of the titration of peptide with metal and of metal with peptide allowed the resolution of the Cd2+/Cys-Gly system, whereas in the analysis of the Cd2+/gamma-Glu-Cys system the analysis of a single titration experiment was sufficient. The analysis of the shape of the resulting pure voltammograms and concentration profiles of the resolved components suggested the presence of two different types of bound Cd2+ in the two systems considered, that could be attributed to Cd2+ bound to one or two sulfur atoms to form complexes of stoichiometry 1:1 and 1:2. respectively.
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PMID:Study of Cd2+ complexation by the glutathione fragments Cys-Gly (CG) and gamma-Glu-Cys (gamma-EC) by differential pulse polarography. 1199 68

Multivariate curve resolution with alternating least squares (MCR-ALS) is applied for the first time to the simultaneous analysis of electrochemical and spectroscopic data. Then, a data analysis is done with augmented matrices constituted by Differential Pulse Polarography and Circular Dichroism data submatrices. The use of proper, and different for each submatrix, constrains in the iterative ALS optimization allows to obtain chemically meaningful results constituted by a common matrix containing the concentration profiles, and two matrices with the pure electrochemical and spectroscopic signals. MCR-ALS is applied to the study of the complexation of Cd by Cys-Gly, a glutathione-fragment of great interest for understanding metal-phytochelatins complexation.
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PMID:Multivariate curve resolution applied to the simultaneous analysis of electrochemical and spectroscopic data: study of the Cd(II)/glutathione-fragment system by voltammetry and circular dichroism spectroscopy. 1738 31

A differential pulse polarographic (DPP) study of the Pb(2+)/Cys-Gly, Pb(2+)/gamma-Glu-Cys, Pb(2+)/PC(2) and Pb(2+)/PC(3) systems is performed, being PC(2) and PC(3) the phytochelatins of general structure (gamma-Glu-Cys)(n)-Gly, with n=2 and 3, respectively. Analysis of DPP data is assisted by multivariate curve resolution with alternating least squares (MCR-ALS) method in order to establish the complexes formation sequence and their final stoichiometries. DPP signals of these systems present, besides overlapping of peaks due to free metal ion and metal complexes, interference of mercury anodic signals. Despite these complications, MCR-ALS allows us to propose a model of complexation for each system, and some tentative structures for the complexes.
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PMID:Soft modelling for the resolution of highly overlapped voltammetric peaks: application to some Pb-phytochelatin systems. 1907 10

Phytochelatins (PC(n), (gamma-Glu-Cys)(n)Gly) are cysteine-rich peptides synthesized by plants which are involved in metal bioregulation and phytoremediation. Multivariate Curve Resolution by Alternating Least Squares (MCR-ALS) is applied to voltammetric data obtained from the analysis of the competitive binding of Cys or Cys-Gly with PC(2) or PC(3) by Cd(2+). The displacements between ligands, the chain length dependence on the competitive binding to PC(n) and the possible existence of mixed ligand metal-complexes are investigated. The shape analysis of the resulting pure voltammograms and concentration profiles of the components resolved by MCR-ALS suggests that ligands containing more thiol groups are able to displace the shorter chain ligands from their metal complexes, whereas the opposite does not happen. Electrochemical results are compared with ESI-MS measurements.
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PMID:Cadmium binding in mixtures of phytochelatins and their fragments: a voltammetric study assisted by multivariate curve resolution and mass spectrometry. 2002 86