It shall be the duty of the prosecuting attorney of each county to prosecute all suits for taxes under this chapter. County collectors shall have power, with the approval of the county commission, or, in St. Louis City, the approval of the mayor thereof, to employ such attorneys as may be deemed necessary to aid and assist the prosecuting attorney in conducting and managing such suits; and the court in which suit is brought shall, if plaintiff obtain judgment, allow such attorneys a reasonable fee for bringing and conducting such suit which shall be taxed against the defendant and paid as other costs in the case. At the request of the collector, the governor may direct the attorney general to assist in the prosecution of any such suits.