The corporation is declared to be performing a public function on behalf of those citizens of the state whose shares and deposits, with respect to which the corporation is organized, are to be protected and to be a public instrumentality of the state of Tennessee for those purposes. Accordingly, the corporation and all properties at any time owned by it, with the exception of real estate properties, and the income therefrom, and all notes, bonds, debentures and other obligations issued by it, and the income therefrom shall be exempt from all taxation in the state of Tennessee. Also, for purposes of the Tennessee Securities Act of 1980, compiled in title 48, chapter 1, part 1, and any amendment thereto or substitution therefor, notes, bonds, debentures and other obligations issued by the corporation shall be deemed to be securities issued by a public instrumentality or a political subdivision of the state of Tennessee.