Abstract
The extracellular hemoglobin of Glossoscolex paulistus (HbGp) has an extraordinary molecular mass of 3.6 MDa, with its oligomeric structure arranged as two superposed hexagonal discs forming a "bracelet". The quaternary structure of HbGp has 144 globin chains and 36 non-globin chains (named linkers). The HbGp dissociates in alkaline pH and in the presence of high surfactant concentrations…