We present quantum calculations for the low-energy dynamics of electrons interacting with glycine molecules in the gas phase. The scattering equations are formulated within a symmetry-adapted, single-center expansion of both continuum and bound electrons, and the interaction forces are obtained from a combination of ab initio calculations and a nonempirical modeling of exchange plus correlation effects. Several open-channel (shape) resonances are obtained, and the features of the excess electron resonant wave functions are related to the experimental findings about the dissociative electron attachment (DEA) processes that follow the initial formation of those transient negative ions.