  We study the influence of a strong AGN outburst on the surrounding galaxies.
The AGN is assumed to reside in a group of galaxies, and an outburst excites a
shock wave in the hot gas in the group. We calculate the impact of the shock
wave on the galaxies. We find that if the energy of the outburst is extremely
large (E_AGN ~6x10^61 erg) as the one recently observed in clusters, the impact
is strong enough to strip the cold interstellar medium in the disc of the
galaxies in the inner region of the group. Moreover, even in the outer region
of the group, the warm gas in the halo of the galaxies would be stripped, even
if the energy of the outburst is ~6x10^60 erg. These would decrease star
formation activity of the galaxies. If these galaxies fall into the group
centre through dynamical friction and their interstellar medium is the fuel of
the supermassive black hole in the AGN, the outburst would serve as feedback.
While this mechanism works only when E_AGN is extremely large, such outbursts
have not been observed in groups at low redshift; it would work at high
redshift rather than at low redshift.
