1 Metal preferences and metallation
نویسندگان
چکیده
The metal-binding preferences of most metalloproteins do not match their metalrequirements. Thus, metallation of an estimated 30% of metalloenzymes is aided by metaldelivery systems, with ~25% acquiring preassembled metal-cofactors. The remaining ~70% are presumed to compete for metals from buffered metal-pools. Metallation is further aided by maintaining the relative concentrations of these pools as an inverse function of the stabilities of the respective metal complexes. For example, magnesium enzymes always prefer to bind zinc and these metals dominate the metalloenzymes without metal-delivery systems. Therefore, the buffered concentration of zinc is held at least a million-fold below magnesium
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