Roles of N- and C-terminal domains in the ligand-binding properties of cytoglobin

N and C-terminal domains of human cytoglobin (Cygb) were explored to clarify physiological functions. Although both domains of Cygb showed no significant effect in binding of exogenous ligand; C-terminal domain, peculiar to mammalian Cygbs, contributed to regulate superoxide-scavenging activity slightly and to improve structural stability significantly.279