Maximal green sequences for quantum and Poisson CGL extensions

We prove that the quantum and classical cluster algebras for all members of the axiomatically defined classes of symmetric quantum and Poisson Cauchon-Goodearl-Letzter extensions possess maximal green sequences in the sense of Keller. Previously, maximal green sequences were constructed for explicit families of cluster algebras; many of those can be recovered from the general result for CGL extensions.