  We calculate the contributions of the Kaluza-Klein (KK) modes to the
gamma-penguins, gluon-penguins, gamma-magnetic penguins and chromomagnetic
penguins in the Appelquist, Cheng and Dobrescu (ACD) model with one universal
extra dimension. Together with our previous calculation of Z^0 penguin diagrams
(See http://arxiv.org/abs/hep-ph/0212143) this allows to study the impact of
the KK modes on the decays B -> X_s gamma, B -> X_s gluon, B -> X_s mu^+ mu^-
and K_L -> pi^0 e^+ e^- and on the CP-violating ratio epsilon'/epsilon. For the
compactification scale 1/R= 300 GeV the perturbative part of the branching
ratio for B -> X_s mu^+ mu^- is enhanced by 12 % while the zero in the A_FB
asymmetry is shifted from \hat s_0=0.162 to \hat s_0=0.142. The sizable
suppressions of Br(B -> X_s gamma) ~ 20 % and Br(B -> X_s gluon) ~ 40 % could
have interesting phenomenological implications on the lower bound on 1/R
provided the experimental and theoretical uncertainties will be decreased.
Similar comments apply to epsilon'/epsilon that is suppressed relative to the
Standard Model expectations with the size of the suppression depending
sensitively on the hadronic matrix elements. The impact on K_L -> pi^0 e^+ e^-
is below 10 %. We point out a correlation between the zero \hat s_0 in the A_FB
asymmetry and Br(B -> X_s gamma) that should be valid in most models with
minimal flavour violation.
