The City Manager, the City Secretary and such other City officers and employees as the City Commission may require, shall, before entering upon the duties of their offices, enter into a good and sufficient fidelity bond in a sum to be determined by the City Commission, payable to the City of Port Isabel and conditioned upon the faithful discharge of the duties of such persons and upon the faithful accounting for all monies, credits, and things of value coming into the hands of such persons, and the bonds shall be signed by a company authorized to do business under the laws of the State of Texas, and the premium on such bonds shall be paid by the City of Port Isabel and such bonds must be in form acceptable to the City Commission.