Structural hierarchy in erythrocruorin, the giant respiratory assemblage of annelids.

@article{Royer2000StructuralHI,
  title={Structural hierarchy in erythrocruorin, the giant respiratory assemblage of annelids.},
  author={William E. Royer and Kristen Strand and Marin van Heel and Wayne A. Hendrickson},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  year={2000},
  volume={97 13},
  pages={7107-11}
}
Many annelids, including the earthworm Lumbricus terrestris, have giant cooperative respiratory proteins (molecular masses greater than 3.5 million Da) freely dissolved in the blood, rather than packaged in cells. These complexes, termed either erythrocruorins or hemoglobins, are assembled from many copies of both hemoglobin subunits and nonhemoglobin or "linker" subunits. In this paper, we present the crystal structure of Lumbricus erythrocruorin at 5.5-A resolution, which reveals a remarkable… CONTINUE READING