Some insects have a globin exclusively in their fast-growing larval stage. This is the case in the 4th-instar larva ofToku-nagayusurika akamusi, a common midge found in Japan. In the polymorphic hemoglobin comprised of 11 separable components, hemoglobinVII (Ta-VIIHb) was of particular interest. When its ferric met-form was exposed to pH from , the distal histidine was found to swing away from theE7 a result, the iron(III) was converted from a hexacoordinate to a pentacoordinate form by a concom-itant loss of the axial water ligand. .
