  We show how the gauge symmetry representations of the massless particle
content of gauged supergravities that arise in the AdS/CFT correspondences can
be derived from symmetric subgroups to be carried by string theory vertex
operators in these compactified models, although an explicit vertex operator
construction of IIB string and M theories on AdSxS remains elusive. Our
symmetry mechanism parallels the construction of representations of the Monster
group and affine algebras in terms of twisted conformal field theories, and may
serve as a guide to the perturbative description of the IIB string on AdSxS.
