49607-15-0Relevant academic research and scientific papers
An Azo Coupling Strategy for Protein 3-Nitrotyrosine Derivatization
Liu, Yuxin,Zhou, Pengcheng,Da, Honghong,Jia, Huiyi,Bai, Feifei,Hu, Guodong,Zhang, Baoxin,Fang, Jianguo
supporting information, p. 11228 - 11232 (2019/08/07)
Herein, a strategy for the selective derivatization of 3-nitrotyrosine-containing proteins using the classic azo coupling reaction as the key step is described. This novel approach featured multiple advantages and was successfully applied to detect picomole levels of protein tyrosine nitration in biological samples.
AFFINITY-ASSISTED PROTEIN MODIFICATION AND RECYCLING
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Paragraph 0228, (2016/08/17)
The present invention provides methods for preparing a protein conjugate having a defined number of conjugate groups. The method includes: forming a mixture containing a macrocyclic matrix material and a plurality of proteins; eluting the proteins from th
Reduction of the nitro group to amine by hydroiodic acid to synthesize o-aminophenol derivatives as putative degradative markers of neuromelanin
Wakamatsu, Kazumasa,Tanaka, Hitomi,Tabuchi, Keisuke,Ojika, Makoto,Zucca, Fabio A.,Zecca, Luigi,Ito, Shosuke
, p. 8039 - 8050 (2014/07/08)
Neuromelanin (NM) is produced in dopaminergic neurons of the substantia nigra (SN) and in noradrenergic neurons of the locus coeruleus (LC). The synthesis of NM in those neurons is a component of brain aging and there is the evidence that this pigment can be involved in the pathogenesis of neurodegenerative diseases such as Parkinson's disease. NM is believed to derive from the oxidative polymerization of dopamine (DA) or norepinephrine (NE) with the participation of cysteine, dolichols and proteins. However, there are still unknown aspects in the chemical structure of NM from SN (SN-NM) and LC (LC-NM). In this study, we designed a new method to synthesize o-aminophenol compounds as putative degradation products of catecholamines and their metabolites which may be incorporated into NM. Those compounds are aminohydroxyphenylethylamine (AHPEA) isomers, aminohydroxyphenylacetic acid (AHPAA) isomers and aminohydroxyethylbenzene (AHEB) isomers, which are expected to arise from DA or NE, 3,4-dihydroxyphenylacetic acid (DOPAC) or 3,4-dihydroxyphenylmandelic acid (DOMA) and 3,4-dihydroxyphenylethanol (DOPE) or 3,4- dihydroxyphenylethyleneglycol (DOPEG), respectively. These o-aminophenol compounds were synthesized by the nitration of phenol derivatives followed by reduction with hydroiodic acid (HI), and they could be identified by HPLC in HI hydrolysates of SN-NM and LC-NM. This degradative approach by HI hydrolysis allows the identification of catecholic precursors unique to SN-NM and LC-NM, which are present in catecholaminergic neurons.
Easy oxidation and nitration of human myoglobin by nitrite and hydrogen peroxide
Nicolis, Stefania,Pennati, Andrea,Perani, Eleonora,Monzani, Enrico,Sanangelantoni, Anna Maria,Casella, Luigi
, p. 749 - 757 (2007/10/03)
The modification of human myoglobin (HMb) by reaction with nitrite and hydrogen peroxide has been investigated. This reaction is important because NO2- and H2O2 are formed in vivo under conditions of oxidative and nitrative stress, where protein derivatization has been often observed. The abundance of HMb in tissues and in the heart makes it a potential source and target of reactive species generated in the body. The oxidant and nitrating species produced by HMb/H 2O2/NO2- are nitrogen dioxide and peroxynitrite, which can react with exogenous substrates and endogenous protein resi dues. Tandem mass analysis of HMb modified by stoichiometric amounts of H2O2 and NO2- indicated the presence of two endogenous derivatizations: oxidation of C110 to sulfinic acid (76 %) and nitration of Y103 to 3-nitrotyrosine (44%). When higher concentrations of NO2- and H2O2 were used, nitration of Y146 and of the heme were also observed. The two-dimensional gel-electrophoretic analysis of the modified HMbs showed spots more acidic than that of wild-type HMb, a result in agreement with the formation of sulfinic acid and nitrotyrosine residues. By contrast, the reaction showed no evidence for the formation of protein homodimers, as observed in the reaction of HMb with H2O2 alone. Both HMb and the modified HMb are active in the H2O2/NO 2--dependent nitration of exogenous phenols. Their catalytic activity is quite similar and the endogenous modifications of HMb therefore have little effect on the reactivity of the protein intermediates.
