Metallochaperones functions

The sequence for delivery of copper ions to SOD1 passes from the copper transporter (Ctr) by an unknown pathway to the copper chaperone for SOD1 (CCS) and by a studied pathway from CCS to SOD1. The CCS protein has been studied structurally and found to be similar to other copper chaperones such as those discussed above—Atxl and Atoxl (Hahl). Copper chaperone for superoxide dismutase (CCS) differs from other copper metallochaperones in that it folds into three functionally distinct protein domains with the N-terminal end of domain I... 

Three Ni-confaintng enzymes (see Nickel Enzymes Cofactors) appear to utilize Ni metallochaperones for enzyme activation. UreE appears to function in NP+ delivery to urease. The Klebsiella aerogenes protein binds 6 Ni per dimer, whereas that from Bacillus pasteurii binds a single Ni per dimer. The metal content differences arise from a His-Asp-His sequence near the middle and a histidine-rich region at the carboxyl terminus of the former protein. Truncated K aerogenes UreE protein, missing the His-rich... 

The maintenance of optimal zinc levels in bacteria is required for cell function and survival. In an effort to probe the cellular response to Zn(II) deficient and excess stresses and to identify any potential cytoplasmic Zn(II)-metallochaperones, DNA microarrays were used. Although many Zn(II)-responsive genes were identified, no plausible candidates for cytoplasmic Zn(II)-metallochaperones were identified. This result warrants a new model to explain intracellular Zn(II) transport in bacteria, and a novel hypothesis that involves a role of the ribosomes in Zn(II) storage and transport is offered. 

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