Haloperoxidases are enzymes capable of formation of carbon^halogen bonds in the presence of hydrogen peroxide and halide ions. A mechanism of halogenation catalyzed by heme-and metal-independent bacterial haloperoxidases di¡ers from other representatives of this group of enzymes. Here we report for the ¢rst time that bacterial non-heme haloperoxidases possess a phosphatase activity. Chloroperoxidase from Serratia marcescens W 250 puri¢ed up to homogeneity is shown to catalyze p-nitrophenylphosphate hydrolysis (K m value, 1.8 þ 0.1 mM at pH 5.7). The reaction is activated by Mg 2+ and F 3 , and is inhibited by WO 4 23 , tartrate, acetate and phosphate anions. The irreversible inhibition by phenylmethanesulfonyl £uoride, modi¢cator of serine residue in active site, decreases in the presence of phosphate ions. A mechanism of phosphoesters hydrolysis by non-heme haloperoxidases is proposed. ß

A non-haem chloroperoxidase was isolated from the enteric bacterium Serratia marcescens. The enzyme was purified to homogeneity by heat treatment, ammonium sulfate precipitation, ion exchange chromatography, gel filtration and dye-ligand affinity chromatography. Native chloroperoxidase has a molecular mass of 58 kDa and consists of two identical subunits of 29 kDa. Whereas chloroperoxidase catalyses only the bromination of monochlorodimedone, indole is chlorinated by this enzyme. Chloroperoxidase also catalyses the oxidation of amino to nitro groups. The enzyme is thermostable and does not lose any activity when incubated at 65 degrees C for 2 h. Comparison of the first 15 amino-terminal amino acids showed a sequence identity of 80% to the chloroperoxidases from Streptomyces lividans and Pseudomonas pyrrocinia. However, no precipitation band was obtained in the Ouchterlony agar diffusion assay with antibodies raised against the chloroperoxidases from Pseudomonas pyrrocinia and Streptomyces aureofaciens Tü24.

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In this paper, an approach is developed that allows one to solve an applied problem of identifying hidden factors of geopolitical influence. It uses the principal component analysis. The solution of the problem is based on the principal components and the method of informative selection of the components of the response of the linear regression model. A numerical example is given on the basis of data on the cost of armament of a number of leading countries.

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