  We demonstrate theoretically how the Kondo effect may be observed in the
transport of spinless electrons through a quantum dot. The role of conduction
electron spin is played by a lead index. The Kondo effect takes place if there
are two close levels in the dot populated by a single electron. For
temperatures exceeding the Kondo temperature $T\gg T_K$ the conductance is
maximal if the levels are exactly degenerate. However, at zero temperature the
conductance is zero at the SU(2) symmetric point, but reaches the unitary limit
$G = e^2/h$ for some finite value of the level splitting $\Delta\eps\sim T_K$.
Introducing the spin-1/2 for electrons and having two degenerate orbital levels
in the dot allows to observe the SU(4) Kondo effect in a single dot coupled to
two leads.
