Filing with the secretary of state.

Any mortgage, deed of trust, security agreement or similar security instrument, or instrument supplemental thereto, or amendatory or in satisfaction thereof, covering any real or personal property situate in more than one county in this state, which is made to secure the payment of bonds, notes or other obligations issued, or to be issued, by any public utility, rural electric cooperative, telephone company or railroads shall be executed and acknowledged in the same manner as are conveyances of real estate and shall be filed in the office of the secretary of state. The secretary of state shall endorse his certificate upon the filed instrument, specifying thereon the day and hour of the instrument's receipt, and the file number assigned to it, which shall be evidence of such facts. The secretary of state shall retain the instrument in his office, and filing the instrument in his office shall be notice to all the world of its existence and contents from the time of filing.