Hemerythrin dioxygen transport

As noted earlier, three solutions to the problem of dioxygen transport have evolved hemoglobin (Hb), hemocyanin (He), and hemerythrin (Hr). Their remarkable distribution over plant and animal kingdoms is shown in Figure 4.8.The hemoglobins and myoglobins found in plants, snails, and vertebrates all appear to share a common, very ancient ancestor. There is some evidence now for a common ancestral hemocyanin.The appearance of hemerythrin in a few annelid worms is an evolutionary curiosity. These few words and the diagram will... 

Proton-coupled electron transfer (PCET) is known to play an important role in a variety of biological processes, including microbial iron transport by ferric enterobactin, enzyme catalysis in systems such as fumarate reductase and nitrate reducatase, and dioxygen binding by the non-heme iron protein hemerythrin. " As such, pH-dependent electrochemical studies can play an important role in unraveling these mechanisms. The most heavily studied biological system known to involve PCET is cytochrome c oxidase, the terminal electron-transfer complex of the mitochondrial respiratory chain, which catalyzes the reduction of molecular oxygen to water. ... 

Hemerythrin is a dioxygen carrier protein responsible for reversible O2 binding and oxygen transport, and it was the first enzyme from the elass of binuclear non-... 

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