The legislature by general law may provide for the Texas Higher Education Coordinating Board or its successor or successors to enter into bond enhancement agreements with appropriate entities with respect to any bonds issued under Section 50b-4, 50b-5, or 50b-6 of this article or under any other provision or former provision of this article authorizing similar bonds. Payments due from the coordinating board under a bond enhancement agreement with respect to the principal of or interest on the bonds shall be treated for purposes of this constitution as payments of the principal of and interest on the bonds, and money appropriated for the purpose of paying the principal of and interest on the bonds as they mature or become due may be used to make payments under bond enhancement agreements authorized by this section with respect to the bonds.