ULK1 and infection: Infection with P. bovis increased protein expression levels of AMPKα, p-AMPKα, ULK1, p-ULK1 and LC3II/LC3I, but decreased SQSTM1/p62 protein expression in bMECs compared to the control group (Figures 4A, B, Figure 1SC), suggesting that autophagy induced by P. bovis was activated in bMECs.