Phosphorylates the antibiotic amicoumacin A (Ami), leading to its inactivation. Mediates natural B.subtilis resistance to the drug. amicoumacin A + ATP = ADP + amicoumacin A 2-phosphate + H(+) Knockout mutant is susceptible to amicoumacin A. Belongs to the pseudomonas-type ThrB family.