Recent experimental observations are shown to be quantitatively consistent with an extended concept of space-time having a discrete extra dimension of two points at the distance of 11.8 fm together with a nontrivial metric structure. In such a space-time, fermions appear in pair with their Kaluza-Klein siblings. The usual electromagnetic field is accompanied with a new vector boson X17, which receives a mass of 17 M eV from another Kaluza-Klein partner, a scalar boson H of a mass in the range of 0.5−793 keV via an abelian Higgs mechanism. At a low energy scale, where nucleons can be treated as structureless in a good approximation, the natural particle model involving nucleons, electron, neutrino and their Kaluza-Klein partners coupled to the electromagnetic field and the massive vector boson X7 can lead to new phenomenological consequences, which are verifiable at the currently accessible energy.