Deinococcus soli sp. nov., a gamma- and uv-radiation-resistant bacterium from north-west China

An ionizing- and UV-radiation-resistant bacterial strain, designated ZLM-202T, was isolated from an arid soil sample collected from Xinjiang Province, north-west China. The soil sample was irradiated before serial dilution plating was performed using twofold-diluted marine agar. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZLM-202T was a member of the genus Deinococcus, exhibiting sequence similarities of 86.3-92.2% to the type strains of recognized Deinococcus species. Strain-ZLM-202 was strictly aerobic and showed optimum growth at 30-37 degrees C and pH 7.0. The major respiratory menaquinone was MK-8. The major fatty acids were 16:1 omega7c, 16:0, 15:1 omega6c, 15:0 iso and 16:1 omega5c. L-ornithine was detected in its peptidoglycan. The polar lipid profile consisted mainly of various unknown phosphoglycolipids, aminophospholipids, glycolipids and phospholipids. The DNA G + C content was 65.5 mol. %. The strain was shown to be extremely resistant to gamma radiation (> 10 kGy) and UV light (> 600 J m(-2)). On the basis of the phylogenetic, chemotaxonomic and phenotypic data, strain ZLM-202T represents a novel species of the genus Deinococcus, for which the name Deinococcus soli sp. nov. is proposed. The type strain is ZLM-202T (= CCTCC AB 208223T = KCTC 13419T).     

The asynchrony of gamma- and beta-chain synthesis during human erythroid cell maturation. III. gamma- and beta-mRNA in immature and mature erythroid clones

The synthesis of the β-crystallin polypeptides has been studied in different regions of the embryonic chicken lens. Seven β-crystallin polypeptides ranging in molecular weight from approximately 19,000 (19K) to 35,000 (35K) daltons were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Each polypeptide was synthesized in a rabbit reticulocyte cell-free system supplemented with RNA from the embryonic lens fiber cells suggesting that each is encoded by a separate mRNA. Analysis of the cell-free translation products of the RNAs from 6-, 15-, and 19-day-old embryonic chicken lens fibers demonstrated that all seven polypeptides are translated at each of the stages and that the proportion of β-crystallin mRNAs increases as the chicken embryo matures. Fingerprints of methionine-containing tryptic peptides indicated that the three predominant β-crystallin polypeptides synthesized in the reticulocyte lysate (20K, 26K, and 35K) have related but distinct primary structures. Surprisingly, both the 35K β-crystallin polypeptide and its mRNA were selectively absent from the cells in the central region of the epithelium. Synthesis of this polypeptide from extracted RNAs was detected in the elongating cells of the equatorial region of the epithelium and from the fiber cells. In contrast to the 35K polypeptide, the six lower-molecular-weight β-crystallin polypeptides were synthesized in a reticulocyte lysate directed by RNAs extracted from all three regions of the lens. These data indicate that lens cell elongation and fiber cell differentiation in the embryonic chicken are accompanied by the appearance of the mRNA for the 35K polypeptide.     

Synthesis of tetrazole analogs of gamma- and delta-amino acids.

N-benzyloxycarbonyl-protected alpha- or beta-amino alcohols, easily prepared from alpha- and beta-amino acids, were converted into aldehydes and directly reacted with (triphenyl phosphoranylidene) acetonitrile, leading to unsaturated nitriles. Treatment of nitriles with NaN(3) and ZnBr(2) produced unsaturated gamma- and delta-amino tetrazoles, which were deprotected and converted to the corresponding saturated compounds by catalytic hydrogenation. For the case of delta-amino tetrazole, the methylation of the acidic moiety occurred after treatment with CH(2)N(2), leading to the N(1)- and N(2)-methylated constitutional isomers, which were separated by column chromatography and hydrogenated.     

An assay for pyrimidine deoxyribonucleoside kinase using gamma-32P-labeled ATP.

A rapid, simple and sensitive assay for pyrimidine deoxyribonucleoside kinase is described. After phosphorylation of unlabeled nucleoside substrate through the transfer of the γ-phosphate of [γ-³²P]ATP, the reaction mixture is subjected to 1 n HCl at 100°C. The β- and γ-phosphates of unreacted ATP are hydrolyzed to inorganic phosphate while the 5′-phosphate of the pyrimidine deoxyribonucleotide product is not hydrolyzed. Radioactive phosphate remaining in the supernatant fluid after precipitation of inorganic phosphate corresponds to product and is measured by liquid scintillation spectrometry. Evidence is presented suggesting that pyrimidine and purine ribonucleoside kinase activity can also be determined by this assay.     

DNA sequence variants in the G gamma-, A gamma-, delta- and beta-globin genes of man

DNA prepared from 60 unrelated individuals was cleaved with one of eight different restriction endonucleases and the resulting DNA fragments were separated by agarose gel electrophoresis. DNA fragments containing G gamma-, A gamma-, delta- or beta-globin genes were detected by Southern blot hybridization, using as probe either a 32P-labeled cloned DNA copy of rabbit beta-globin messenger RNA or labeled human beta- and G gamma- globin cDNA plasmids. Three types of variant restriction enzyme patterns of globin DNA fragments were detected in otherwise normal individuals. One variant pattern, found in only one person, was caused by an additional restriction endonuclease Pst I cleavage site in the center of the delta- globin gene intervening sequence; the subject was heterozygous for the presence of this cleavage site and was shown to have inherited it from her mother. Another variant pattern resulted from the appearance of an endonuclease Hind III cleavage site in the intervening sequence of the A gamma-globin gene; this variant is polymorphic, with a gene frequency for the presence of the intragenic Hind III site of 0.23. This Hind III cleavage site polymorphism is also found in the G gamma-globin gene intervening sequence and thus the polymorphism itself appears to be duplicated over the pair of gamma-globin loci. These variants can be used to derive an approximate estimate of the total number of different DNA sequence variants in man.     

Nicotine and its metabolites. Radioimmunoassay for gamma-(3-pyridyl)-gamma-oxo-N-methylbutyramide

A radioimmunoassay has been developed for the nicotine metabolite γ-(3-pyridyl)-γ-oxo-N-methylbutyramide. The sensitivity and specificity of the assay allow the determination of this compound at the picomole level in the presence of several structurally related molecules including nicotine and seven other nicotine metabolites. The assay has been used to characterize the enzyme system present in rabbit liver extract responsible for the conversion of cotinine to the oxoamide, and to measure oxoamide levels in urine, sera, and amniotic fluid of smokers. High-pressure liquid chromatography was used as an independent method to follow the enzymatic oxidation and in conjunction with the radioimmunoassay to analyze the urine samples.     

Human gamma- to beta-globin gene switching using a mini construct in transgenic mice.

The developmental regulation of the human globin genes involves a key switch from fetal (gamma-) to adult (beta-) globin gene expression. It is possible to study the mechanism of this switch by expressing the human globin genes in transgenic mice. Previous work has shown that high-level expression of the human globin genes in transgenic mice requires the presence of the locus control region (LCR) upstream of the genes in the beta-globin locus. High-level, correct developmental regulation of beta-globin gene expression in transgenic mice has previously been accomplished only in 30- to 40-kb genomic constructs containing the LCR and multiple genes from the locus. This suggests that either competition for LCR sequences by other globin genes or the presence of intergenic sequences from the beta-globin locus is required to silence the beta-globin gene in embryonic life. The results presented here clearly show that the presence of the gamma-globin gene (3.3 kb) alone is sufficient to down-regulate the beta-globin gene in embryonic transgenic mice made with an LCR-gamma-beta-globin mini construct. The results also show that the gamma-globin gene is down-regulated in adult mice from most transgenic lines made with LCR-gamma-globin constructs not including the beta-globin gene, i.e., that the gamma-globin gene can be autonomously regulated. Evidence presented here suggests that a region 3' of the gamma-globin gene may be important for down-regulation in the adult. The 5'HS2 gamma en beta construct described is a suitable model for further study of the mechanism of human gamma- to beta-globin gene switching in transgenic mice.     

Synthesis and characterization of a series of novel glutamic gamma-15N-anilide dipeptides.

The preparation of a series of novel Cbz-Gln-Gly dipeptide derivatives is reported, wherein the gamma-carboxamide groups of the glutamine side chains have been modified to gamma-15N-anilides which are substituted in the para position with -NO2, -Cl, -H, -CH3, -OCH3, and -N(CH3)2. Characterization of the free anilines (p(kappa)a values and 15N NMR chemical shifts) and corresponding gamma-anilides (15N NMR chemical shifts and FTIR wavenumbers) is also reported. Correlation of these physicochemical data to Hammett substituent parameters ((sigma)para) is discussed. These novel dipeptide derivatives should prove to be generally useful for structure-function enzymology studies of gamma-glutamyl transferring enzymes.