["Beta-lactamase enzymogram": an agar adaptation of the iodometric method (author's transl)].
This paper deals with an agar-gel adaptation of the Perret-Novick iodometric titration of degradation products from beta-lactam antibiotics when they are submitted to a beta-lactamase action. Petri dishes containing an agar-gel make up from the classical iodine-iodide-starch system, initially present a dark blue colour. When beta-lactam compounds are opened by beta-lactamases from crude extracts or whole bacteria, the gel is locally destained. Two experimental variants of this procedure are proposed. This semi-quantitative, inexpensive, accurate and simple method is very convenient for routine experiments. Thus with crude extracts or even whole cells, information can be obtained about beta-lactamase specific activities, substrate profils or activity of inhibitors such as cloxacillin or clavulanic acid.
D000362:Agar; D004926:Escherichia coli / Q000201:enzymology; D007455:Iodine / Q000032:analysis; D008722:Methods; D010400:Penicillin G; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000378:metabolism*
D065093:beta-Lactamase Inhibitors; D000362:Agar; D007455:Iodine; D001618:beta-Lactamases; D010400:Penicillin G
L'enzymogramme des beta-lactamases: adaptation en cel de la méthode iodométrique.