Someone may have already let you know, but just in case:
The father of Johann Michael Propst - married to 3rd wife Catherine Elizabeth (last name unknown) - was named Hans Michael Propst.
Johann Michael Propst was not a 'jr' but had a son (born to 2nd wife Maria Margaretha Corell) named Johann Michael Propst, Jr.
Also, I hope the following can be of use to you:
Johann Propost, B. abt. 1620, Germany. SP: Unknown
Hans Michael Propost, B. 1659, Germany; D. 1695. SP: Agatha Plintzing, m. Aug 27, 1678
Hans Michael Propst, B. 1679, Germany. D. 1745, Pendleton, Co WV.
SP: Barbara, B. 1670, Germany. D. 1745, Pendleton, Co WV.
Johann Michael Propst, B. 1712 Germany; D. 1789, Propstburg, Pendleton Co, WV. Will Dated: December 19, 1785.
SP: Catherine Elizabeth (last name Unknown), B. bf. 1720; M. 1745; D. 1804, Pendleton Co WV at the age of 84.
Children Listed: Catharina Barbara, Maria Elizabeth, Frederick George (B. 1748), George Peter, Maria Eva, and Heinrich
Frederick George Propst, B. 1748, Pendleton Co, WV; D. 1801, Pendleton, Co, WV SP: Barabara Swadley, B. 1748/49, Augusta County, VA (later Pendleton Co, WV); D. Nov 11, 1829, Pendleton Co, WV
Johannes (John) Propst, B. btw. 1770-1775, Pendleton Co WV; D. aft. 1850, Jackson Co TN
SP: Elizabeth Doval, B. 1780, Alma, Page Co, VA; M. May 20, 1800, Rockingham Co, VA; D. 1847, Jackson Co, TN
Children: John and Nancy.
Nancy Propst, B. abt. 1802, Pendleton, Co, WV; M. Nov. 9, 1816, Barren Co, KY; D. 1852, Jackson Co., TN.
SP: William Speakman, B. abt. 1790, Barren Co., KY; D. 1849, Jackson County, TN.
Nancy is my ggg-grandmother.