Hemoglobin from the Antarctic fish Notothenia coriiceps neglecta

The erythrocytes of the Antarctic benthic teleost Notothenia coriiceps neglecta, of the family Nototheniidae, have been found to contain two hemoglobins, purified by ion-exchange chromatography and obtained in crystalline form [l]. The study of the oxygen-binding properties indicated that both hemoglobins are functionally similar and show marked Bohr and Root effects. The globin chains of each component have been purified by HPLC; Hb 1 and Hb 2 appeared to have one of the two globin chains in common. Hb 1 is the major hemoglobin of N. coriiceps neglecta, accounting for about 90% of the total blood content. A similar situation has been shown to occur in seven other species of Nototheniidae, where the content of Hb 1 and of the more acidic Hb 2 was 80 - 90% and 5 - 15% of total, respectively; species of other Antarctic fish families (Bathydraconidae, Harpagiferidae and Rajidae) contained only one hemoglobin [2, 31. Thus, the hemoglobin multiplicity in Antarctic teleosts, in comparison with temperate or tropical fishes [4], is very low. This paper reports the complete amino acid sequence of the c1 chain of N. coriiceps neglecta Hb 1, which adds to the few known sequences of fish globins. It is the only sequence of a globin from a marine poikilothermic teleost established so far and, moreover, is the first one referring to a coldadapted Antarctic organism. Preliminary accounts of some of these findings have been presented [5, 61.