this unusually low v ( fe-co ) stretching frequency in cytochrome p-450scc , compared with other co-complexed hemoproteins such as co-hemoglobin and -myoglobin , is presumably due to the thiolate ligation to the heme iron trans to co and due to the linear and perpendicular configuration of co binding to the heme .
C0008381
cytochrome p-450scc
C0018974
hemoproteins