  We solve a functional version of the problem of twist quantization of a
coboundary Lie bialgebra (g,r,Z). We derive from this the following results:
(a) the formal Poisson manifolds g^* and G^* are isomorphic; (b) we construct a
subalgebra of U(g^*), isomorphic to S(g^*)^g. When g can be quantized, we
construct a deformation of the morphism S(g^*)^g subset U(g^*). When g is
quasitriangular and nondegenerate, we compare our construction with
Semenov-Tian-Shansky's construction of a commutative subalgebra of U(g^*). We
also show that the canonical derivation of the function ring of G^* is
Hamiltonian.
