Summary. The molecular weight of human lactotransferrin and serotransferrin. Moreover, our results confirm the single chain structure of LTF and STF proposed by others and do not agree with the multiple chain structure we suggested previously, in particular on the basis of C-terminal amino acid determination by hydrazinolysis.As is the case of bovine and murine LTF, human LTF led to the formation of oligomeric structures in concentrated aqueous solutions.Introduction.