In addition to the powers conferred upon the commission to secure the bonds in the Nebraska Highway Bond Act, the commission shall have power in connection with the issuance of bonds to enter into such agreements, consistent with the act and not in derogation or limitation of the act, as it may deem necessary, convenient, or desirable concerning the use or disposition of the money in the fund, the State Highway Capital Improvement Fund, or the bond fund including the pledging or creation of any security interest in such money and the doing of or refraining from doing any act which the commission would have the right to do to secure the bonds in the absence of such agreements. The commission shall have the power to enter into amendments of any such agreements, consistent with the Nebraska Highway Bond Act and not in derogation or limitation of the act, within the powers granted to the commission by the act and to perform such agreements. The provisions of any such agreements may be made a part of the contract with the holders of the bonds.