  The extra-dimensional model in which the bulk geometry is a slice of anti-de
Sitter space is a particularly attractive extension of the Standard Model as it
allows to address the gauge hierarchy problem, as well as the mass hierarchy
prevailing among fermions. However, to allow for the masses of the Kaluza-Klein
excitations of the known particles to be near the Terascale without conflicting
with the high-precision electroweak data, one needs to promote the gauge
symmetry to a left-right structure SU(2)_L x SU(2)_R x U(1) which incorporates
a new quark b', the SU(2)_R doublet partner of the heavy top quark. We show
that this new quark will contribute to the main production process of Higgs
bosons at the LHC: the gluon-gluon fusion mechanism which proceeds through
heavy quark triangular loops. In most of the parameter space in which the
measured values of the heavy t,b quark masses are reproduced, the gg -> Higgs
production cross section is significantly altered, even if the b' quark is too
heavy to be directly accessible, m_b' > ~1TeV. Finally, we briefly discuss the
new Higgs production and decay channels involving the b' quark.
