Solid-phase enzyme-receptor assay (SPERA): a competitive-binding assay for glycopeptide antibiotics of the vancomycin class.
A solid-phase enzyme-receptor assay (SPERA) has been developed for glycopeptide antibiotics of the vancomycin class such as teicoplanin, vancomycin, ristocetin, avoparcin, actaplanin, A-47934, A-41030, and A-35512-B. The assay exploits the mechanism of most action of these antibiotics, which is based on their interaction with acyl-D-alanyl-D-alanine, a constituent of the walls of most growing bacterial cells. The antibiotics and enzyme-labeled teicoplanin compete for a synthetic analog of the biological receptor, albumin-epsilon-aminocaproyl-D-alanyl-D-alanine. The various antibiotics produced different competition curves, 50% displacement being obtained with antibiotic concentrations ranging from 0.04 to 4 mg/L, vancomycin and actaplanin being the weakest and strongest competitors, respectively. For teicoplanin in human serum the intra-assay CV was 7.2%, the interassay CV was 11.2%, and the analytical recovery 94%. Teicoplanin concentrations obtained by SPERA (chi) correlated well with those obtained by microbiological assay (y): y = 1.03 chi + 0.053 (r = 0.943; n = 60). We conclude that SPERA is a powerful tool for identification and quantitative detection of glycopeptide antibiotics, even in complex media.
Corti
A
A
Rurali
C
C
Borghi
A
A
Cassani
G
G
D000900:Anti-Bacterial Agents / Q000032:analysis*; D001667:Binding, Competitive; D004796:Clinical Enzyme Tests / Q000379:methods*; D006020:Glycopeptides / Q000032:analysis; D006735:Horseradish Peroxidase / Q000378:metabolism; D006801:Humans; D012310:Ristocetin / Q000032:analysis; D017334:Teicoplanin; D014640:Vancomycin / Q000032:analysis*
D000900:Anti-Bacterial Agents; D006020:Glycopeptides; D012310:Ristocetin; D017334:Teicoplanin; D014640:Vancomycin; C044842:A 41030; C040926:actaplanin; D006735:Horseradish Peroxidase; C016249:avoparcin