Phosphorylates GarA. May play a role in metabolic regulation via control of the phosphorylation status of GarA. Plays a crucial role in the survival of mycobacteria within host macrophages, by blocking the intracellular degradation of mycobacteria in lysosomes. Required for intrinsic antibiotic resistance. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Kinase activity is regulated by the redox status of the environment via the rubredoxin domain. Autophosphorylation is not essential for kinase activity, but it promotes binding to GarA. The C-terminal domain also contributes to the regulation of activity. Inhibited by a specific small molecular-weight inhibitor, the tetrahydrobenzothiophene AX20017. Homodimer. Interacts with the FHA domain of GarA. Also detected in growth media, suggesting that it can be translocated into host macrophages under specific conditions. Contains an N-terminal rubredoxin domain, a central kinase domain and a C-terminal TPR domain. Autophosphorylated. In vitro, incorporates up to four phosphate groups on Thr-23, Thr-32 and Thr-63 and/or Thr-64 and/or Ser-65. In vivo, is probably phosphorylated only on Thr-63. Disruption causes delayed mortality in mice. Mutant accumulates glutamate and glutamine. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family.