Subunit Composition and O2 Binding of the Crustacean Hemocyanins: Interspecific Relationships

The monomeric subunit composition and oxygen binding properties of hemocyanins were examined in 9 taxonomic groups of 43 crustacean species and 1 hybrid. In native polyacrylamide electrophoresis the banding pattern was highly species specific, even in closely related congeners. In less closely related taxa, there was little apparent relationship between phylogenetic affinity and banding pattern. Within a taxonomic group, pH dependence was the most highly conserved and O2 affinity was the most diverse of the O2 binding properties investigated. In congeneric but not sibling species, O2 affinity was more highly correlated with an environmental variable such as temperature than with phylogenetic affinity. Only in very closely related groups found in similar environments were different O2 binding properties correlated with differences in particular electrophoretic bands.