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Updated: Aug 7, 2026

Measuring In Vitro ATPase Activity for Enzymatic Characterization
Published on: August 23, 2016
Studies on the ATPase of Bacillus cereus
I H Higuti1, M Stencel, K H Nascimento
1Departamento de Bioquímica, Universidade Federal do Paraná, Curitiba, PR., Brazil.
Abstract:
The membrane ATPase (EC 3.6.1.3) of Bacillus cereus was solubilized by a 'shock-wash' process and purified. The non-specific phosphatase contaminant was separated by glycerol density gradient centrifugation. The optimum temperature was 39.5 degrees C and the pH optimum at 7.5. On SDS-polyacrylamide gel electrophoresis two classes of subunits were observed in equal proportions with molecular weights of 70 K and 83 K. The effect of various compounds on the enzymatic activity was studied. The enzyme was insensitive to NaN3, oligomycin and to divalent cations, but was inhibited by citrate and oxalate.
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