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Updated: Aug 8, 2026

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A Purification and In Vitro Activity Assay for a (p)ppGpp Synthetase from Clostridium difficile
Published on: November 3, 2018
Purification and properties of glucosaminephosphate isomerase of Proteus mirabilis
Abstract:
A glucosamine-P isomerase has been identified in Proteus mirabilis. The 113-fold purified enzyme exhibits a pH optimum of 7.5 with a secondary maximum at 8.5 and a temperature optimum at 37 degrees C. The apparent Km was 13.3 mM for fructose-6-P and 18.8 mM for L-glutamine. Molecular weight of the enzyme has been estimated as 120 000 and the protein can be dissociated in four subunits by SDS-polyacrylamide electrophoresis.
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