Richmond-Sykes classification

Organism P-Lactamase producers, % Chromosomal Enzyme origin % Plasmid Richmond-Sykes classification... 

CD50, Curative dose for 50% of mice following subcutaneous dosing Ih and 5h post infection strains producing plasmid-mediated yS-lactamase Richmond-Sykes classification of enzymes. Clavulanic acid alone was ineffective at 50 mg/kg. For abbreviations, see footnote to Table 6.1. 

The most recent classification ofyff-lactamases is that of Bush [17], who proposed a modification of the Richmond-Sykes system based primarily on biochemical characteristics, using substrate and inhibitor profiles in addition to physical data. This system, which also includes yS-lactamases from Gram-positive bacteria, seems likely to become the preferred system for the classification of yS-lactamases in the future. 

Substrate, benzylpenicillin with 5 min pre-incubation substrate, cephaloridine with 5 min pre-incubation enzyme classification based upon Richmond-Sykes. 

Substrate, nitrocefin after 5 min pre-incubation concentration of inhibitor, 5.0 /ig/ml for Gram-negative bacteria and 1.0 //g/ml for S.a. Enzyme classification based on Richmond-Sykes. For abbreviations, see footnote to Table 6.1. 

The inhibitors at doses of 2 or 10 mg/kg were mixed with varying doses of amoxycillin and administered subcutaneously to groups of 5 mice at time intervals of 1 and 5 hours or 1,3 and 5 hours post infection enzyme classification based upon Richmond-Sykes system. For abbreviations, see footnote to Table 6.1. 

Until recently, the most frequently used scheme for the classification of Gram-negative /8-lactamases was that of Richmond and Sykes [11, 12]. In... 

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