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P M Rabinovich

Publications and source records attributed to P M Rabinovich.

At least 19 recordsLinked to original sources
PubMed1992

[Purification and properties of GTP-cyclohydrolase from Bacillus subtilis].

Highly purified GTP-cyclohydrolase was obtained by fractionation of cell extracts with ammonium sulfate, ion-exchange and hydrophobic chromatography. The N-terminal amino acid sequence and amino acid composition of the protein were determined. According to SDS-PAGE data, the molecular weight of the enzyme is 45 kDa. The active enzyme has several isoforms separable by native electrophoresis. The maximal enzyme activity is determined at 1.5 mM Mn2+; 70% of enzymatic activity is detected with Mg2+. The enzyme is inhibited by heavy metal ions and chelators and is inactive in the absence of thiol-reducing agents. The enzyme activity is detected in a broad range of pH with a maximum at pH 8.2. The pyrimidine product of the GTP-cyclohydrolase reaction. 2.5-diamino-6-hydroxy-4-ribosylaminopyrimidine-5'-phosphate was purified and identified. Another product of this reaction is pyrophosphate.

Amino Acids↗
PubMed1991

[Subcloning and study of the GTP-cyclohydrolase gene of Bacillus subtilis].

Bacillus subtilis GTP-cyclohydrolase gene and its deletion derivatives were subcloned in Escherichia coli cells. The position of the gene within the riboflavine operon was defined. The deletion of the 14 kDa fragment from the N-end of GTP-cyclohydrolase gene did not affect the enzyme activity.

Bacillus subtilis↗
PubMed1987

[Study of the 210-degree region of the Bacillus subtilis chromosome using recombinant plasmids].

The 210 degrees region of Bacillus subtilis DNA containing the rib operon and genes for the first (dapA) and last (lysA) steps of lysine biosynthesis was cloned. PstI fragments of B. subtilis m.m. 4.7 MD DNA containing the lys and the proximal part of rib operon were isolated from different B. subtilis strains (SB25 and SHgW) and shown to have the same restriction and genetic maps. The restriction mapping of EcoRI fragment of B. subtilis m.m. 6.3 MD DNA containing the rib operon has been carried out.

Bacillus subtilis↗
PubMed1985

[Riboflavin operon in Bacillus subtilis contains additional promoters].

Using the methods of molecular cloning permitted to show that riboflavin operon of Bacillus subtilis contains four promoters. Three of them are functionally active in the Bacillus subtilis system. The main promoter of the operon with regulatory region was cloned in plasmid pPL603. Cells containing the constructed plasmid pGM32 are resistant to chloramphenicol. The level of resistance is regulated by concentration of riboflavin (the effector of operon). The following model of rib-operon has been proposed: (Formula: see text).

Bacillus subtilis↗
PubMed1983

[Cloning the operon genes of riboflavin biosynthesis in Bacillus subtilis on plasmid vector pBR322 in Escherichia coli].

The operon for riboflavine biosynthesis of Bacillus subtilis wild type and its operator-constitutive derivative have been cloned in Escherichia coli cells on the plasmid pBR322 vector. The plasmids constructed were able to transform strains of E. coli and Bac. subtilis from Rib- to Rib+ phenotype. A DNA insert into the EcoRI site of pBR322 causes a decrease in tetracycline gene expression. The operator of the riboflavine operon of Bac. subtilis does not participate in regulation of the operon expression in E. coli cells.

Bacillus subtilis↗
PubMed1983

[3 linkage groups of the genes of riboflavin biosynthesis in Escherichia coli].

Using transposon Tn5 inactivation technology a collection of Escherichia coli mutants defective in riboflavine biosynthesis was obtained. All mutations were distributed within three linkage groups. With the help of P1-transduction mapping, group I mutations (ribA locus) were localized near cysB locus (28 min of the standard 100 min E. coli map) and mutations of group II (ribB locus) were mapped near tolC locus (66 min). The location of group III mutations was approximately determined by the F' complementation analysis: this linkage group lies in the region of 56-60 min of the E. coli map.

Chromosome Mapping↗
PubMed1982

[Bacillus licheniformis as an object for the propagaton of heterologous genetic material from bacilli].

Bacillus licheniformis was transformed with plasmids pUB110 and pJJ10 (pUB110 - pBR322) isolated from Bac. subtilis and Escherichia coli, respectively. It was revealed that the structure and genetic properties of the plasmids did not change during the transformation process. pJJ101 (pJJ10-rib) DNA isolated from E. coli and containing helper pJJ10 plasmid was used, as a recipient. It was shown that pJJ101 rib markers were "rescued" by the resident plasmid during transformation of Bac. licheniformis (pJJ10). Plasmid pLP1 containing ribB, ribD, Kmr genes and the pUB110 replicator, was isolated from the transformants. pLP1 plasmid might be considered as a detected derivative of the parental pJJ101 plasmid. The deletion is presented by 3,9 MD segment that contains the pBR322 replicator. pLP1 DNA is capable of transforming plasmidless strains of Bac. licheniformis and Bac. subtilis.

Bacillus↗
PubMed1979

[Riboflavin auxotrophs of Escherichia coli].

Escherichia coli riboflavin auxotrophs having a different level of riboflavin requirement were isolated. This auxotrophic mutations are located near cysB93 and trpA62 markers. The complementary effect of Bacillus subtilis riboflavin operon linked with pPR1 hybrid plasmid with rib8-1 and rib1-1 mutations was obtained.

Bacillus subtilis↗
PubMed1978

[Amplification of the riboflavin operon genes of Bacillus subtilis in Escherichia coli cells].

Amplification of Bacillus subtilis DNA fragments was performed in Escherichia coli using plasmid RSF2124. The main principle of isolation and cloning hybrid plasmids was described using genes of riboflavin operon as a model. Bac. subtilis DNA was treated with restriction endonuclease EcoR; followed by the agarose gel electrophoretic separation of the resulting fragments. Gels were sliced, DNA was eluted from the corresponding slices and used to transform Bac. subtilis auxotrophs rib A72, rib S110 and rib D107. DNA fraction with the molecular weight 7 . 10(6) daltons restored prototrophy of these mutants. DNA of this fraction was ligated with EcoRI treated plasmid RSF2124 DNA and used for transformation of E. coli rk-mk+. Ampicillin resistant transformants which had lost the colicin production ability, were selected. The presence of riboflavin genes within the hybrid plasmids was detected by transformation of B. subtilis auxotrophs. Three hybrid plasmids (pPR1, pPR2 and pPR3), containing a fragment of Bac. subtilis DNA with the molecular weight 6.8 . 10(-6) daltons including riboflavin operon, were selected. The analysis of the transformation activity of Bac. subtilis DNA and plasmid pPR1 DNA revealed, that there was no restriction activity of Bac. subtilis cells against plasmid DNA amplified in E. coli. Heteroduplex analysis has shown that plasmids pPR1 and pPR2 differ in the orientation of Bac. subtilis DNA fragment. DNA of these plasmids restored prototrophy of the several studied E. coli riboflavin auxotrophs.

Bacillus subtilis↗