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Week 5 - Metal Chaperones ( contribute new content,first 250 words)
Metal chaperones or Metallochaperones are compounds that operate as an intracellular shuttle service for metal ions to attack a specific protein metalloenzymes/metalloproteins and achieve metal ion transfer through specific protein-protein interactions. This process helps maintain control of cellular metal ion homeostasis to support the intracellular concentration of the available metal ions be close to zero.

Majority of the biochemical reactions require these metallochaperones as cofactors since the complexity of active sites varies from one metal ion with distinct protein ligands to polynuclear clusters as well as exogenous ligands such as water or sulfide, modified protein side chains, and protein side chains. The process of incorporation of metal ion cofactors into Metalloproteins are very important for biological processes, involving photosynthesis, nerve transmission, respiration and defense against toxic agents.

The concept of metallochaperones proceeds from the investigation of metal ions such as copper(I) and zinc(II) into metalloenzymes in order to understand the structure, molecular mechanism and coordination chemistry of metallochaperones. These mediated cofactors come from primary studies of copper chaperones which are divided into three different groups: the copper chaperones for superoxide dismutase, the Atx1-like chaperones, and the copper chaperones for cytochrome c oxidase.

1. Copper (I) Metallochaperones
Copper is an enzyme co factor that is an essential nutrient but also is extremely toxic in high intramolecular concentration  to living cells.Copper toxicity is a problem of agricultural, environmental and medical influence, also is the causation  of  metal-metabolism abnormalities and neuropsychiatric problems including Menkes and Wilson's diseases.The mechanism of the copper metallochaperones is to regulate the efflux mechanism, which is  indispensable for preventing accumulation of copper.

Week 10 - Metal Chaperones ( contribute new content,400 words + 250 words)
There are three fuctional groups which the Copper chaperones are divided into: the Atx1-like chaperone, the copper chaperones for superoxide dismutase, and the copper chaperones for cytochrome c oxidase. there is no explanation how these chaperones obtain copper, however it could be given through direct interactions using Ctr family of membrane transporters.

It is not proved yet how these chaperones obtain copper initially however there is an assumption this process is done with the Ctr family of membrane transporters with direct interactions. All three types of chaperones bind with Cu(I)  implementing cystine ligands. The Atx1 protein shuttles copper to the transport ATPase Ccc2 in the trans-Golgi network, then Ccc2 transfers the copper inside the vesicles, where it gets combined to form the multicopper oxidase Fet3 cells. Then, ATX1 together with its the human homolog, Atox1, delivers copper to the Menkes and Wilson disease ATPases for insertion into the ceruloplasmin, the copper chaperones for superoxide dismutase, also  known as CCS proteins, is known to have a minimal intracellular free copper concentrations. It delivers copper to the eukaryotic antioxidant SOD1, also known as zinc superoxide dismultase, playing an important role in the assembly of Cox2, cytochrome c oxidase subunit 2 CuA site

1.1 Atx1-Like Copper chaperones
This functional group is a cytosolic yeast copper chaperone required for copper-dependent iron absorption taking place between metal-binding sites of the diffusible copper-donor and membrane-tethered copper-acceptor proteins. The Atx1 structural motif transporting essential metal ion and then implemented in variety of organism. These Atx1 proteins together with their target ATPases are represented by a preserved CXXC1 metal binding motif. The target ATPases consist up to 6 repeating N-terminal domains with the conserved CXXC metal binding motif, whereas the chaperones contain one motif.

Implementing the response data of structural and mutagenesis analysis implemented a protein-protein recognition, which was predicted based on the negatively charged excess on the target proteins and the positively charged excess on the chaperones. This model consistency is studied implementing resent NMR chemical-shift mapping between Atx1 and Ccc2 interactions, predicting the presence of two and three-coordinate metal exchange intermediates, where two of the CXXC motifs undergo ligand exchange reaction. It is not determined the interaction with Atox1 Atx1 interact and all the target ATPases or just with the selected CXXC containing the domains

Which are predicted to contain different electrostatic surface characteristics allowing for chaperone recognition. Furthermore, once the copper gets inserted into Fet3 and ceruloplasmin and then is translocated into the lumen  inside the Golgi

1.2 Copper Chaperones for Superoxide Dismutase
CCS functional group are identical proteins made up of three domains per monomer. First domain (domain I) is a similar copy of the Atx1-like chaperones including their target domains and they consist of CXXC sequence motif, this domain is located at the N-terminal. The second domain (domain II) is a copy that resembles the structure of SOD1, however it differs by its deficiency in residues which are important for SOD1 activity, this domain is located in the middle. The third domain (domain III) is formed by a conserved CXC sequence motif forming an extended loop structure, this domain is located at the C-terminal with 30 residues which are important for metal trans-residues.

According to spectroscopy data it is suggested to form the metal binding site, cysteines from domain I CXXC motif and domain III CXC motif come together.

A heterodimer composed of one monomer of each protein is obtained when a complex of a crystal structure between the mutant SOD1 and CCS does not bind copper.

1.3 Copper Chaperones for Cytochrome c Oxidase
Structurally not characterized yet, however results from mutagenesis and spectroscopy studies provide background of its binding with copper ions. Cox17 and Sco1 are active sites which copper binds using cystine ligands, Cox17 is known to bind with three cysteine to activate cytostome c oxidase

1.1 Properties of Nickel(II) Cyclam Perchlorate

 * Molecular Formula : Ni(cyclam)(ClO4)2 - cyclam : (1,4,8,11-tetraazacyclotetradecane)
 * Molecular mass: 457.915 g/mol
 * Melting Point: 140°C
 * Boiling Point:
 * Solubility in water: somewhat soluble in most polar solvents