YddG from Escherichia coli promotes export of aromatic amino acids

The inner membrane protein YddG of Escherichia coli is a homologue of the known amino acid exporters RhtA and YdeD. It was found that the yddG gene overexpression conferred resistance upon E. coli cells to the inhibiting concentrations of l-phenylalanine and aromatic amino acid analogues, dl-p-fluorophenylalanine, dl-o-fluorophenylalanine and dl-5-fluorotryptophan. In addition, yddG overexpression enhanced the production of l-phenylalanine, l-tyrosine or l-tryptophan by the respective E. coli-producing strains. On the other hand, the inactivation of yddG decreased the aromatic amino acid accumulation by these strains. The cells of the E. colil-phenylalanine-producing strain containing overexpressed yddG accumulated less l-phenylalanine inside and exported the amino acid at a higher rate than the cells of the isogenic strain containing wild-type yddG. Taken together, these results indicate that YddG functions as an aromatic amino acid exporter.     

Responses of sunflower chlorophyll mutants to increased temperature and oxidative burst

A tolerance of nuclear, plastome, and mitochondrial mutants of sunflower (Helianthus annuus L.) to extreme factors, increased temperature and oxidative stress, which was simulated by hyperbaric oxygenation was studied. In model experiments, activities of superoxide dismutase and catalase were assayed; cytogenetic analysis was used for the assessments of proliferative activity of cells in the root meristem; in field experiments, seedling emergence and growth at the stage of 3–4 leaf pair were evaluated. Most tolerant to increased temperature and oxygen pressure were a plastome en:chlorina-5 mutant and a partial revertant pr6-en:chlorina-7 with a changed structure of mitochondrial DNA.     

Polymorphisms of Tuberculosis Susceptibility Candidate Genes in the Slavonic Population of Siberia: A Pilot Study

The 469+14 G/C (INT4), 1465-85 G/A, and C274T polymorphisms of NRAMP1 and the A/C polymorphism of IL12 3"UTR were analyzed in ethnic Russians with (N = 58) or without (N = 127) tuberculosis (TB) from Tomsk. On evidence of allele and genotype frequencies, none of the polymorphisms was associated with TB. In the healthy controls, the three NRAMP1 polymorphisms were in linkage disequilibrium with each other (p < 0.001) but not with the IL12 polymorphism. Still the four polymorphisms are potentially informative as concerns their association with TB.     

Polymorphisms of the candidate genes for genetic susceptibility to tuberculosis in the Slavic population of Siberia: a pilot study

The 469 + 14 G/C (INT4), 1465 - 85 G/A, and C274T polymorphisms of NRAMP1 and the A/C polymorphism of IL12 3'-UTR were analyzed in ethnic Russians with (N = 58) or without (N = 127) tuberculosis (TB) from Tomsk. On evidence of allele and genotype frequencies, none of the polymorphisms was associated with TB. In the healthy controls, the three NRAMP1 polymorphisms were in linkage disequilibrium with each other (P < 0.001) but not with the IL12 polymorphism. Still the four polymorphisms are potentially informative as concerns their association with TB.     

Structural and Functional Characteristics of the Mutant Plastids from Extranuclear Variegated Forms of Sunflower

The electron-microscopic analysis of extranuclear variegated forms of sunflower demonstrated that plastids from white leaf areas are practically devoid of inner membrane structures. The mutants and the initial (wild-type) green line were compared by the contents of chlorophyll (Chl), carotenoids, and 70S ribosomes and by the activity of Rubisco. A mutant Var10 line was used to demonstrate that the primary characteristic manifestations of Chl deficiency include the synchronous retardation of the synthesis of a specific Chl precursor, 5-aminolevulinate, a decrease in the Chl a/b ratio to the level below that in the wild type, and the reduction of photosystem (PS) I Chl luminance. The progress of photodestructive processes in the mutant aggravated the listed disturbances; as a result, PSII complexes and light-harvesting complexes gradually degraded. The manifestation of the trait of Chl-deficiency notably varied depending on plant growth conditions (primarily, temperature and illumination regimes). The dependence of this manifestation on light and temperature was observed only at the early stage of development of pigment-containing tissues. When plants terminated this stage under low irradiation, they did not become Chl-deficient, and when their leaves were subsequently transferred to the conditions promoting the maximum pigment anomaly, the destructive processes did not advance in the mutant tissue. The authors assume that the plastom mutations under study impair the control over the expression of the structural plastogenes that determine the synthesis of pigment and protein components of the photosynthetic apparatus, rather than directly damage to the primary structures of plastogenes.     

A comparative analysis of tuberculosis susceptibility genetic make-up in Tuvinians and Russians

The results of the first Russian study of polymorphisms of tuberculosis (TB) susceptibility genes SLC11A1, VDR, IL12B, IL1B, IL1RN in Tuvinians from Tuva Republic and Russians from Tomsk city are presented. In Tuvinians, as compared with Russians, the significantly higher prevalence of potentially disease-associated alleles of the genes studied was shown: SLC11A1*543N (0.139 and 0.043, respectively, p = 4.6E-5), IL12B*1188C (0.378 and 0.174, respectively, p = 1.1E-8), VDR*b (0.825 and 0.532, respectively, p = 3.2E-16), IL1B*(+3953A1) (0.865 and 0.806, respectively, p = 0.035). However, no one of these alleles was associated with TB in Tuvinians, whereas, in Russians TB patients, in comparison with the controls, there was a higher prevalence of the following markers: IL1RN*A2 (0.258 and 0.186, respectively, p = 0.024), SLC11A1*274T (0.251 and 0.164, respectively, p = 0.009), IL12B*1188C (0.240 and 0.174, respectively, p = 0.044), ILIB*(+3953A2) (0.259 and 0.194, respectively, p = 0.044). Distinct patterns of linkage disequilibrium between pairs of the polymorphisms studied in Tuvinians and Russians were shown. At whole, the data obtained demonstrate the ethnic specificity of the distribution and pathogenetic significance of the alleles of the TB susceptibility genes.     

Comparative analysis of the tuberculosis susceptibility genetic make-up in Tuvinians and Russians

Polymorphisms of the tuberculosis (TB) susceptibility genes SLC11A1, VDR, IL12B, IL1B, and IL1RN were studied, for the first time in Russia, in Tuvinians from the Tyva Republic and ethnic Russians from Tomsk. Compared with Russians, Tuvinians had significantly higher frequencies of potentially pathological alleles SLC11A1*543N (0.139 vs. 0.043, P = 4.6 · 10^?5), IL12B*1188C (0.378 vs. 0.174, P = 1.1 · 10^?8), VDR*b (0.825 vs. 0.532, P = 3.2 · 10^?16), IL1B*(+3953A1) (0.865 vs. 0.806, P = 0.035), and IL1RN*A1 (0.849 vs. 0.786, P = 0.030). However, none of the alleles was associated with TB in Tuvinians. Compared with healthy subjects, Russian patients with TB had higher frequencies of alleles IL1RN*A2 (0.258 vs. 0.186, P = 0.024), SLC11A1*274T (0.251 vs. 0.164, P = 0.009), IL12B*1188C (0.240 vs. 0.174, P = 0.044), and IL1B*(+3953A2) (0.259 vs. 0.194, P = 0.044). The structure of linkage disequilibrium in pairs of alleles differed between Tuvinians and Russians. In total, the results suggest ethnic specificity of the distribution and pathogenetic significance of the alleles of the TB susceptibility genes.     

Quantitative determination of metabolites in human urine by <Superscript>1</Superscript>H NMR spectroscopy

Conditions for registration of urinary ¹H NMR spectra have been optimized in order to achieve maximal accuracy of quantitative analysis. Urinary samples from patients with acute pancreatitis have been investigated and spectral data of identified urinary metabolites and results of their quantitative determination are given. Employment of ¹H NMR spectra is perspective for the development of new laboratory diagnostic methods.