[Interactions of ceftriaxone with beta-lactamases including those which hydrolyze cefotaxime].
As it occurs with most of 3rd generation cephalosporins, ceftriaxone has few, if any, interactions with penicillinase-type beta-lactamases, such as TEM-1, TEM-2 or PIT-2. These poor interactions are characterized by an extremely low hydrolysis, associated to a poor affinity of these compounds for the penicillinases. Conversely, ceftriaxone, as cefotaxime, shows a high affinity for chromosomally-mediated cephalosporinases (indole-positive Proteus, Enterobacter, Pseudomonas...), which is characterized by Ki values ranging from about 0.05 to 1 microM. Within these beta-lactamases, the hydrolysis of ceftriaxone, as that of cefotaxime, is always low, but significant. Then few beta-lactamases are able to hydrolyze more efficiently cefotaxime, as cefuroxime, such as those produced by P vulgaris and K oxytoca. Within these enzymes, ceftriaxone is also hydrolyzed, in a way quite similar to that of cefotaxime.
D002439:Cefotaxime / Q000378:metabolism; D002443:Ceftriaxone / Q000378:metabolism*; D007700:Kinetics; D001618:beta-Lactamases / Q000378:metabolism*
D002443:Ceftriaxone; D001618:beta-Lactamases; D002439:Cefotaxime
Etude des interactions du ceftriaxone avec les bêta-lactamases y compris celles qui hydrolysent le céfotaxime.