Conventional and Molecular Identification of Bacteria with Magnesite Enrichment Potential from Local Quarries in Erzurum

In this study, the bacteria having ore enrichment potential were isolated from three different magnesite quarries located in Erzurum-Askale borderlines. The obtained isolates were identified and characterized according to the conventional (morphological, physiological and biochemical tests) and molecular techniques (fatty acid methyl ester profiles (FAME), BOX PCR and 16S rDNA). According to sequence analysis, they were determined as Exiguobacterium aurantiacum (4), Exiguobacterium sibiricum (2), Bacillus sp. (2), Staphylococcus epidermidis (2), Staphylococcus haemolyticus (1), Shewanella baltica (1) and Klebsiella oxytoca (1), respectively.     

Phylogenetic position of Rickettsia tsutsugamushi and the relationship among its antigenic variants by analyses of 16S rRNA gene sequences

Abstract The 16S rRNA gene sequences of Rickettsia tsutsugamushi and Rickettsia sibirica were determined by PCR and DNA sequencing. Phylogenetic analysis revealed that R. sibirica is positioned in a cluster of the genus Rickettsia with a similarity value of 98.1–99.6%, whereas R. tsutsugamushi is located apart from the cluster with a similarity value of 90.2–90.6%. This evidence suggests that R. tsutsugamushi should be excluded taxonomically from the genus Rickettsia . The phylogenetic classification of six antigenic variants in R. tsutsugamushi moderately reflected their antigenic relationship known in closely and distantly related strains.     

Development of a selective and sensitive polymerase chain reaction assay for the detection of Mycoplasma pirum

Abstract A new assay using the polymerase chain reaction to amplify a 173-nucleotide DNA fragment within the 16S ribosomal RNA gene of Mycoplasma pirum has been developed. The assay selectively amplified DNA from all strains of M. pirum tested with a high level of sensitivity, even in a context of human DNA. DNA from other mollicute species, including those closely related to M. pirum , from bacteria phylogenetically close to mollicutes ( Clostridium innocuum, C. ramosum and Bacillus subtilis ), from Escherichia coli and from human peripheral blood mononuclear cells, did not produce the amplified DNA product specific for M. pirum .     

Metabolic Enzyme Alterations and Astrocyte Dysfunction in a Murine Model of Alexander Disease With Severe Reactive Gliosis

Alexander disease (AxD) is a rare and fatal neurodegenerative disorder caused by mutations in the gene encoding glial fibrillary acidic protein (GFAP). In this report, a mouse model of AxD (GFAP^Tg;Gfap^+/R236H) was analyzed that contains a heterozygous R236H point mutation in murine Gfap as well as a transgene with a GFAP promoter to overexpress human GFAP. Using label-free quantitative proteomic comparisons of brain tissue from GFAP^Tg;Gfap^+/R236H versus wild-type mice confirmed upregulation of the glutathione metabolism pathway and indicated proteins were elevated in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which had not been reported previously in AxD. Relative protein-level differences were confirmed by a targeted proteomics assay, including proteins related to astrocytes and oligodendrocytes. Of particular interest was the decreased level of the oligodendrocyte protein, 2-hydroxyacylsphingosine 1-beta-galactosyltransferase (Ugt8), since Ugt8-deficient mice exhibit a phenotype similar to GFAP^Tg;Gfap^+/R236H mice (e.g., tremors, ataxia, hind-limb paralysis). In addition, decreased levels of myelin-associated proteins were found in the GFAP^Tg;Gfap^+/R236H mice, consistent with the role of Ugt8 in myelin synthesis. Fabp7 upregulation in GFAP^Tg;Gfap^+/R236H mice was also selected for further investigation due to its uncharacterized association to AxD, critical function in astrocyte proliferation, and functional ability to inhibit the anti-inflammatory PPAR signaling pathway in models of amyotrophic lateral sclerosis (ALS). Within Gfap⁺ astrocytes, Fabp7 was markedly increased in the hippocampus, a brain region subjected to extensive pathology and chronic reactive gliosis in GFAP^Tg;Gfap^+/R236H mice. Last, to determine whether the findings in GFAP^Tg;Gfap^+/R236H mice are present in the human condition, AxD patient and control samples were analyzed by Western blot, which indicated that Type I AxD patients have a significant fourfold upregulation of FABP7. However, immunohistochemistry analysis showed that UGT8 accumulates in AxD patient subpial brain regions where abundant amounts of Rosenthal fibers are located, which was not observed in the GFAP^Tg;Gfap^+/R236H mice.     

Critical Role of Lipid Scramblase TMEM16F in Phosphatidylserine Exposure and Repair of Plasma Membrane after Pore Formation

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