  In this work, we perform a dynamical study of the $B^{(*)}$ and $\bar K$
interaction and show that the newly reported $X(5568)$ or $X(5616)$ cannot be
assigned to be an isovector $B\bar{K}$ or $B^*\bar{K}$ molecular state. We
continue to investigate the isoscalar $B^{(*)}\bar{K}$ systems, and the
$B^{(*)}\bar{K}$ systems with isospin $I=0,1$, and predict the existence of
several isoscalar $B^{(*)}\bar K^{(*)}$ molecular states. A new task of
exploring open-bottom molecular states will be created for future experiments.
