  Spin states and persistent currents are investigated theoretically in a
mesoscopic ring with an embedded magnetic ion under a uniform magnetic field
including the spin-orbit interactions. The magnetic impurity acts as a
spin-dependent $\delta$-potential for electrons and results in gaps in the
energy spectrum, consequently suppresses the oscillation of the persistent
currents. The competition between the Zeeman splittings and the $s$-$d$
exchange interaction leads to a transition of the electron ground state in the
ring. The interplay between the periodic potential induced by the Rashba and
Dresselhaus spin-orbit interactions and the $\delta$-potential induced by the
magnetic impurity leads to significant variation in the energy spectrum, charge
density distribution, and persistent currents of electrons in the ring.
