Purification and properties of alkaline phosphatase from bacillus cereus

Abstract

Extracellular and membrane-bound alkaline phosphatases were produced at the middle stationary phase of growth by a strain Bacillus cereus. Twenty two percent of the enzyme activity was secreted into the culture media. An extracellular alkaline phosphatase (AP I) and a membrane-bound alkaline phosphatase (AP II) were purified 282-fold and 70-fold, respectively by a combination of chromatographic methods. Enzyme activity of alkaline phosphatase preparations was maximal at pH 9.5. Both enzymes were inhibited by EDTA and were reactivated by addition of Ca2+. The molecular weight of AP I was estimated to be 43 ± 1 kDa, and that of AP II was estimated to be 44 ± 1 kDa. Alkaline phosphatase activity of both enzyme preparation s was completely lost by heating at 80°C. © 2010 Taylor and Francis Group, LLC.