32817-15-5Relevant articles and documents
Copper2+ Binding to α-Synuclein. Histidine50 Can Form a Ternary Complex with Cu2+ at the N-Terminus but Not a Macrochelate
Tian, Yao,Stanyon, Helen F.,Barritt, Joseph D,Mayet, Uroosa,Patel, Pelak,Karamani, Elena,Fusco, Giuliana,Viles, John H.
, (2019)
α-Synuclein (αSyn) forms amyloid fibrils in the neurons of Parkinson's disease (PD) patients'. Despite a role for Cu2+ in accelerating αSyn fibril formation, coupled with reports of copper dis-homeostasis in PD, there remain controversies surrounding the coordination geometry of Cu2+ with αSyn. Here we compare visible circular dichroism (CD) spectra of Cu2+ loaded on to full-length αSyn together with four peptides that model aspects of Cu2+ binding to the N-Terminus and histidine50 of αSyn. With glycine as a competitive ligand, the affinity of Cu2+ for full-length αSyn is determined to have a conditional dissociation constant, at pH 7.4, of 0.1 nM. A similar affinity of 0.3 nM is determined for the tripeptide Met-Asp-Val(MDV) that mimics the N-Terminus of αSyn, while the incorporation of a putative histidine side chain in the N-Terminal complex facilitates the formation of a macrochelate with the histidine, which results in an increase in the affinity for Cu2+ to 0.03 nM at pH 7.4. Comparisons of the visible absorbance and CD spectra over a range of pH values also indicates that the MDV tripeptide closely models Cu2+ binding to full-length αSyn and rules out a role for His50 in the primary Cu2+ binding complex of monomeric αSyn. However, there are reports that suggest His50 does form a macrochelate with the N-Terminal Cu2+ complex; we reconcile these conflicting observations by identifying a concentration dependence of the interaction. Only at the higher concentrations can the imidazole nitrogen bind to the N-Terminal Cu2+ to form a ternary complex rather than via a macrochelate. This work shows even for this intrinsically disordered protein a large macrochelate with Cu2+ is not favored. Understanding Cu2+ coordination to αSyn gives a more complete picture of its place in amyloid assembly and cytotoxicity.
Pearlmutter,Stuehr
, p. 858,861 (1968)
Ligand Decomposition in the Photolysis of Copper(II)-Amino-acid Complexes in Aqueous Solution
Das, Suresh,Johnson, G. R. Alastair,Nazhat, Najdat B.,Saadalla-Nazhat, Rajiha
, (1984)
Ligand decomposition following charge-transfer excitation of bis(glycinato)cuprate(II) in aqueous solution gives NH3 and HCHO as the final products in yields equivalent to the reduction of the metal Cu(I).An intermediate, observed by flash photolysis, is
Synthesis method of p-methylsulfonylphenylserine copper
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Paragraph 0024-0041;, (2019/05/08)
The invention discloses a synthesis method of p-methylsulfonylphenylserine copper. One or more of copper hydroxide, basic cupric carbonate and copper oxide is or are used as a copper-bearing agent tosynthesize DL-p-methylsulfonylphenylserine copper, the reaction time is shortened, a mother liquor is used indiscriminately for multiple times, and the quantity of copper-bearing wastewater is reduced. The synthesis method comprises the following steps: adding the copper-bearing agent into a reaction flask, adding glycine, para-aldehyde and deionized water or adding the mother liquid in the last batch, reacting for 20 hours at the temperature of 40-55 DEG C, and cooling, filtering, washing and drying after finishing the reaction to obtain a product. The yield is 90% or higher, and the qualitymeets requirements. The method shortens the reaction time, and the copper-bearing mother liquid is used indiscriminately for multiple times.
