[Comparative analysis of the spatial organization of myoglobins. I. Hydrophobicity profiles]

Hydrophobicity profiles of myoglobins in the animal species far remote in the evolutionary series are considerably similar. A complete coincidence as to the arrangement of hydrophobic zones along the polypeptide chain in myoglobins of the compared species (from a man to mollusc) is revealed at the beginning of alpha-helix of B-segment and in the area corresponding to a cluster which embodies a heme- bound water molecule, distal histidine E7 being directed to this cluster. The mollusc myoglobin with two absent (as compared to myoglobins of other species) hydrophobic sites differs in the profile of hydrophobicity most of all. It is supposed that hydrophobic nuclei forming the heme circumference create a globule "skeleton" thus pre-setting general spatial structure of the myoglobin molecule, which is very significant for its functional activity.