Trisodium Phosphate → 2816-24-2

Participants

Reaction Steps

The assay used is based on that of Lederberg (J. Bacteriol. 1950, 60, 381), using an assay mixture comprising 2.8 ml of 50 mM sodium phosphate, pH 7.0, and 0.1 ml of 68 mM ONPG. 0.1 ml aliquots of both purified enzyme and toluene-treated cell suspension, and 10 mg. amounts in 2.9 ml of buffer of freeze dried immobilised whole cell preparation are used for the assays. Assays are carried out at incubation temperature of 65° C. and after the appropriate time interval the reactions are halted by addition of 3 ml aliquots of 0.5 M sodium bicarbonate to each reaction mixture and immediate cooling in an ice bath. The absorbance of the resultant solutions is measured at 410 nm using a Perkin-Elmer 124 double beam spectrophotometer. In the case of whole cell suspensions the assay tubes are centrifuged and in the case of the immobilised cells the mixtures are filtered, to remove cells and polyacrylamide gel respectively prior to measurement of the absorbance.

Provenance & Evidence