Chlorocruorin: A pigment allied to hœmoglobin

Abstract

The name chlorocruorin was given by Ray Lankester (1867) to a pigment dissolved in the blood plasma of Sabellid, Serpulid and Chlorhæmid polychæte worms. Lankester showed that chlorocruorin is related to hæmoglobin, since he obtained a hæmochromogen from it. The pigment is burgundy-red when in concentrated solution, green when dilute. It will be shown below that while chlorocruorin is constructed on the same plan as hæmoglobin, the differences between the two are very much greater than the differences between specific hæmoglobins. Chlorocruorin exists in an oxidised and a reduced state which are of almost the same colour. The reduced form in dilute solution is a slightly yellower green than the oxidised. The oxidised differs, however, spectroscopically from the reduced form in the same manner as oxyhæmoglobin differs from hæmoglobin. Oxychlorocruorin has two bands in the red-green part of the visible spectrum and reduced chlorocruorin one broader one. These bands are situated to the red of the corresponding hæmoglobin bands. Chlorocruorin like hæmoglobin, can act as a peroxidase (Lankester, 1870).