amikacin + GTP <=> 4'-guanylylamikacin + diphosphate
amikacin + gtp <=> 4'-guanylylamikacin + diphosphate
amikacin + GTP <=> 4'-guanylylamikacin + diphosphate
amikacin + gtp <=> 4'-guanylylamikacin + diphosphate