Enzymatic adenylylation by aminoglycoside 4'-adenylytransferase and 2"-adenylyltransferase as a means of determining concentrations of aminoglycoside antibiotics in serum.

A fast and accurate enzymatic estimation of the concentration of aminoglycoside antiobiotics in serum is given by aminoglycoside 4'-adenylyltransferase (synonym: tobramycin adenylyltransferase), a new enzyme recently found in tobramycin-resistant staphylococci (P. Santanam and F. H. Kayser, J. Infect. Dis. [Suppl.], in press). This enzyme is useful in assaying the kanamycins, the butirosins, amikacin, ribostamycin and, if required, the neomycins, tobramycin, and paromomycin. In combination with the assay using aminoglycoside 2''-adenylyltransferase (synonym: gentamicin adenylyltransferase) to determine the level of gentamicin, sisomicin, and tobramycin, a convenient method to estimate a wide range of aminoglycoside antibiotics in patients' sera is described.