Isolation and Properties of Extracellular Alkaline Phosphatase from Bacillus intermedius

M. R. Sharipova^1*, N. P. Balaban¹, A. M. Mardanova¹, N. V. Nekhotyaeva¹, A. A. Dementyev², O. A. Vershinina¹, A. V. Garusov¹, and I. B. Leshchinskaya¹

¹Department of Microbiology, School of Biology, Kazan State University, ul. Kremlevskaya 18, Kazan, 420008 Russia; fax: (8-432) 38-0994; E-mail: Margarita.Sharipova@ksu.ru

²Center for Bioengineering, Russian Academy of Sciences, ul. Vavilova 32, Moscow, 117984 Russia

^* To whom correspondence should be addressed.

Received November 3, 1997; Revision received January 13, 1998

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Alkaline phosphatase (APase) was isolated from the culture liquid of the streptomycin-resistant strain of Bacillus intermedius S3-19 and purified as a homogeneous preparation by ion-exchange chromatography and FPLC. Electrophoresis and gel-filtration revealed that the active enzyme is a monomer with molecular weight of 46-47 kD. The enzyme possessed phosphomonoesterase and phosphodiesterase activities with maximal levels at pH 9.5 and 55°C and was stable until 60°C at pH 8.0-10.0. The isolated APase exhibits a broad specificity towards a wide variety of substrates. The effect of divalent metal ions and other reagents on its catalytic activities was studied. It was concluded that alkaline phosphatase of B. intermedius is similar to the secreted alkaline phosphatases from other Bacillus species in its physicochemical and catalytic properties.

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KEY WORDS: B. intermedius alkaline phosphatase, purification, characterization

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