Mo. Rev. Stat. § 59.290
The recorder of deeds, in counties of the second class, is entitled to appoint the deputies that the recorder of deeds, with the approval of the county commission, deems necessary for the prompt and proper discharge of the duties of his office. The deputies shall possess the qualifications of clerks of courts of record, and may, in the name of their principal, perform the duties of the recorder of deeds, but all recorders of deeds and their sureties are responsible for the official conduct of their deputies. The deputies, appointed as herein provided, shall receive the salaries that are fixed by the recorder of deeds, with the approval of the county commission. The appointment of every deputy shall be in writing, endorsed with an oath of office, similar to that taken by the recorder and subscribed to by the deputy appointed, and filed by the recorder of deeds with the county commission.
§ 59.290, RSMo