Section 8. There shall be a division of professional licensure under the supervision of a commissioner. Said commissioner shall be classified in accordance with section forty-five of chapter thirty and the salary shall be determined in accordance with section forty-six C of said chapter thirty, and shall devote his full time during business hours to the duties of his office. Upon the expiration of the term of office of a commissioner, his successor shall be appointed by the governor for a term coterminous with that of the governor.