Partial Characterization of a Trypsin-Stimulated Cytoplasmic Soluble Adenosine Triphosphatase of Agrobacterium Tumefaciens

A cold-labile trypsin-stimulated adenosine triphosphatase, ATPase (EC. 3.6.1.3) activity has been found associated with the partially purified cytoplasmic soluble fraction of Agrobacterium tumefaciens strain C-58. Chromatographic, electrophoretic, and catalytic studies are also reported. Trypsin activated the enzyme 31% at the pH optimum of between 8.0 and 9.0. The optimum temperature of activity for the enzyme was between 28°C and 50°C, whereas the enzyme was better maintained for several days at 4°C than either at 28°C or 37°C.