[Physicochemical properties and antiproliferative activity of recombinant Yersinia pseudotuberculosis L-asparaginase].

The physicochemical, catalytic, and antiproliferative activity of a recombinant L-asparaginase from Yersinia pseudotuberculosis (YpA) have been studied. The following results were obtained: the K(M) value for L-asparagine is 17 +/- 0.9 microM, the optimal temperature is 60 degrees C, pH is 8.

[Antitumor activity of L-asparaginase from Yersinia pseudotuberculosis].

The cytotoxic activity of L-asparaginases from Yersinia pseudotuberculosis and from Erwinia carotovora were investigated in vitro using several tumor cells lines: Jurkat and Molt-4 (human T-lymphoblastic leukemia), MCF-7 (human breast adenocarcinoma), LnCap (human prostate carcinoma), NGUK1 (rat Gasser node neurinoma). E. coli L-asparaginase produced by "Medak" (Germany) was used as a reference.

[Purification and properties of recombinant Erwinia carotovora L-asparaginase expressed in E.coli cells].

The method of purification Erwinia carotovora recombinant L-asparaginase, expressed in E.coli, including ultrasonic disintegration of biomass, fractionation ammonium sulfate and column chromatography on CM- or SP-Sepharose has been developed. According to SDS-PAAGE the enzyme preparation was homogeneous, its specific activity and yield consist respectively about 620 IU/mg of protein and 75%.

[Isolation and purification of recombinant truncated (delta2-27) cytochrome P450 2B4 expressed in E. coli cells as a fusion protein with glutathione-S-transferase].

This paper describes the modification of the method by Coon and Pernecky (Meth. Enzymol. 1996, 272, 25-34) for purification of truncated (delta 2-27) recombinant form of cytochrome P450 2B4 expressed in E.

[Isolation and specificity of novel restriction endonucleases Bsp40091 and AsiI, isoschizomers of BamHI].

New type II restriction endonucleases AsiI and Bsp40091 are detected in Azotobacter species N55 and Bacillus species 4009, respectively. Purified preparations of the restriction enzymes free from interfering nucleases and phosphatases were obtained by column chromatography on phosphocellulose and heparin-sepharose (Asil) and phosphocellulose and DEAE-cellulose (Bsp40091). The yield of purified AsiI and Bsp40091 was 16 x 10(3) and 8 x 10(3) units per g of wet cells, respectively.