  We consider, for $p$ odd, a $p$--brane coupled to a $(p+1)$th rank background
antisymmetric tensor field and to background Yang-Mills (YM) fields {\it via} a
Wess-Zumino term. We obtain the generators of antisymmetric tensor and
Yang-Mills gauge transformations acting on $p$--brane wavefunctionals
(functions on `$p$-loop space'). The Yang-Mills generators do not form a closed
algebra by themselves; instead, the algebra of Yang-Mills and antisymmetric
tensor generators is a $U(1)$ extension of the usual algebra of Yang-Mills
gauge transformations. We construct the $p$-brane's Hamiltonian and thereby
find gauge-covariant functional derivatives acting on $p$--brane
wavefunctionals that commute with the YM and $U(1)$ generators.
