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971.
A rod-shaped actinobacterium, designated Sco-A25T, was isolated from a red-coloured layer of scoria (volcanic ash) in the Republic of Korea and subjected to a polyphasic taxonomic characterization. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain Sco-A25T is a member of the genus Nocardioides and formed a tight monophyletic unit with the type strain of Nocardioides plantarum (98.7 % gene similarity). LL-Diaminopimelic acid was detected in the cell wall. The predominant menaquinone is MK-8(H4). The polar lipids found were phosphatidylinositol, diphosphatidylglycerol, phosphatidylglycerol, and an unknown phospholipid. The fatty acid profile was represented by large amounts of saturated, unsaturated and iso-branched fatty acids. The DNA G+C content was 71.6 mol %. Genomic DNA similarity between strain Sco-A25T and N. plantarum KCTC 9577T was 47.8 %. On the basis of the results of phenotypic, genetic and phylogenetic analyses presented here, strain Sco-A25T is considered to represent a novel species of the genus Nocardioides, for which the name Nocardioides rubroscoriae sp. nov. is proposed. The type strain is Sco-A25T (=KCTC 19805T = DSM 23986T = NBRC 107916T). 相似文献
972.
Myung Soo Park Seung-Yoon Oh Hae Jin Cho Jonathan J. Fong Woo-Jae Cheon Young Woon Lim 《Antonie van Leeuwenhoek》2014,106(4):593-603
A new species, Trichoderma songyi, was found to be associated with the pine mushroom (Tricholoma matsutake) in Korea. This species was isolated from three different substrates: Tricholoma matsutake basidiomata, as well as roots of Pinus densiflora and soil in the fairy ring. Based on its molecular and phenotypic characteristics, we demonstrate that Trichoderma songyi is unique and distinguishable from closely related species. We performed phylogenetic analyses based on two molecular markers, the genes for both translation elongation factor 1-alpha and the second largest subunit of RNA polymerase II. Phylogenetic analyses showed that Trichoderma songyi is closely related to Trichoderma koningii aggregate and Trichoderma caerulescens. Morphologically, Trichoderma songyi can be distinguished from these closely related taxa by its growth rates, colony morphology on PDA in darkness, and coconut-like odour. Due to the economic importance of the pine mushroom, the relationship between Trichoderma songyi and Tricholoma matsutake should be studied further. 相似文献
973.
J W Kim E Y Kim H H Park J E Jung H D Kim H J Shin W K Lim 《Biochemical and biophysical research communications》2001,289(2):568-572
Tryptophan synthase alpha-subunit from Escherichia coli functionally exists as a heterotetramer of alpha(2)beta(2) with beta-subunit. While wild-type and mutant (F139W, T24M/F139W, and T24L/F139W) alpha-subunits were expressed as a monomer from recombinant plasmids in Escherichia coli, T24A/F139W, T24S/F139W, and T24K/F139W mutant alpha-subunits were abnormally expressed as soluble homodimers in addition to monomers. Monomers of dimer-forming mutant alpha-subunits retain high affinity to beta-subunit, high activity in stimulating catalytic activities of beta-subunit, and nearly intact content of secondary structure, indicating that the global structures of these monomers are identical to that of F139W alpha-subunit. However, fluorescence spectra of Trp139 and ANS binding indicate that significant perturbations occur in the mutant proteins. Interestingly, these defective properties of monomers caused by residue replacement were partially repaired by the dimer formation. As a result, it is suggested that dimers may be formed by domain or loop swapping, and that residue 24 may play important role in maintaining on-pathway of alpha-subunit folding. 相似文献
974.
Diatoms are potentially the most important biomonitors of environmental change in high arctic lakes and ponds, but to date few autecological data are available. Because of the shallow nature of many of these water bodies, a large proportion of taxa are periphytic and planktonic diatoms are absent for the most part. By determining the microhabitat and substrate preferences of these benthic diatom taxa, the potential exists to infer past changes in available habitats from fossil diatom assemblages collected from sediment cores and ultimately to reconstruct past environmental and climatic changes responsible for these shifts in habitat availability. To refine our understanding of high arctic diatom habitat preference, the common diatom taxa found on submerged moss (bryophyte), sediment, and rock substrates from lakes and ponds on Bathurst Island, Nunavut, Canadian High Arctic were examined. The relationships among key limnological variables and the common taxa from each habitat were examined. Many diatom taxa exhibited varying degrees of microhabitat preference, with moss representing the more unique habitat. In addition, the following limnological variables significantly ( P ≤ 0.05) explained the species variance for each of the three substrates: Na + and total nitrogen for moss; total phosphorus (filtered) and pH for rock; and Fe3 + , total phosphorus (unfiltered), total nitrogen, temperature, and pH for sediment. These data can be used to help interpret monitoring and paleolimnological studies in this environmentally sensitive region. 相似文献
975.
Jae-Bong Lee Eun-Ji Jung Hee-Bok Park Shil Jin Dong-Won Seo Moon-Suck Ko In-Cheol Cho Jun-Heon Lee Hyun-Tae Lim 《Molecular biology reports》2014,41(11):7167-7173
Most reproductive traits have low heritability and are greatly affected by environmental factors. Teat number and litter size are traits related to the reproduction ability of pigs. To identify quantitative trait loci (QTLs) for teat number traits, a genome-wide association study (GWAS) was conducted using an F2 intercross between Landrace and Korean native pigs. Genotype analysis was performed using the porcine SNP 60 K beadchip. The GWAS was performed using a mixed-effects model and linear regression approach. When a genome-wide threshold was determined using the Bonferroni method (P = 1.61 × 10?6), 38 single nucleotide polymorphism (SNP) markers in pig chromosome 7 (SSC7) were significantly associated with three teat number traits (total teat number, left teat number, and right teat number). Among these, SNPs in 5 genes (HDDC3, LOC100156276, LOC100155863, ANPEP, SCAMP2) were selected for further study based primarily on their statistical significance. A significant association was detected in SCAMP2 g.25280 G>A for total teat number (P = 2.0 × 10?12), HDDC3 g.1319 G>A SNP for left teat number (P = 2.3 × 10?7), and SCAMP2 g.14198 G>A for right teat number (P = 4.7 × 10?12). These results provide valuable information about the selective breeding for desirable teat numbers in pigs. 相似文献
976.
Saedi TA Moeini H Tan WS Yusoff K Daud HM Chu KB Tan SG Bhassu S 《Molecular biology reports》2012,39(5):5785-5790
White tail disease (WTD) is a serious viral disease in the hatcheries and nursery ponds of Macrobrachium rosenbergii in many parts of the world. A new disease similar to WTD was observed in larvae and post larvae of M. rosenbergii cultured in Malaysia. In the present study, RT-PCR assay was used to detect the causative agents of WTD, M. rosenbergii nodavirus (MrNV) and extra small virus (XSV) using specific primers for MrNV RNA2 and XSV. The results showed the presence of MrNV in the samples with or without signs of WTD. However, XSV was only detected in some of the MrNV-positive samples. Phylogenetic analysis showed that the RNA2 of our Malaysian isolates were significantly different from
the other isolates. Histopathological studies revealed myofiber degeneration of the tail muscles and liquefactive myopathy
in the infected prawns. This was the first report on the occurrence of MrNV in the Malaysian freshwater prawn. 相似文献
977.
Ito S Fujiyama-Nakamura S Kimura S Lim J Kamoshida Y Shiozaki-Sato Y Sawatsubashi S Suzuki E Tanabe M Ueda T Murata T Kato H Ohtake F Fujiki R Miki T Kouzmenko A Takeyama K Kato S 《Molecular cell》2012,45(4):494-504
Cell cycle-dependent expression of canonical histone proteins enables newly synthesized DNA to be integrated into chromatin in replicating cells. However, the molecular basis of cell cycle-dependency in the switching of histone gene regulation remains to be uncovered. Here, we report the identification and biochemical characterization of a molecular switcher, HERS (histone gene-specific epigenetic repressor in late S phase), for nucleosomal core histone gene inactivation in Drosophila. HERS protein is phosphorylated by a cyclin-dependent kinase (Cdk) at the end of S-phase. Phosphorylated HERS binds to histone gene regulatory regions and anchors HP1 and Su(var)3-9 to induce chromatin inactivation through histone H3 lysine 9 methylation. These findings illustrate a salient molecular switch linking epigenetic gene silencing to cell cycle-dependent histone production. 相似文献
978.
The feasibility of using Deinococcus showing strong resistance to both desiccation and ionizing radiation as a dose indicator of gamma radiation exposure was evaluated. Three Deinococcus strains having different levels of radiation resistance, Deinococcus radiodurans (DRD), Deinococcus radiopugnans (DRP), and the DRD pprI mutant (DRM), were selected to develop an appropriate dose indicator for a broad range of exposures. DRD, DRP, and DRM cultures with different numbers of cells [~10(7) to 10(3) colony forming units (CFU)/100 microliter] were lyophilized and subjected to various doses of gamma radiation to determine a critical dose that inhibited bacterial growth completely. Finally, a combination of DRD at ~10(7) and ~10(6) CFU, DRP at ~10(5) CFU, and DRM at ~10(4) CFU successfully indicated exposure to 5, 10, 20, and 30 kGy of gamma radiation, respectively. This study shows the possibility of developing a qualitative indicator of radiation exposure using Deinococcus. 相似文献
979.
Extracts of Phellinus linteus grown on germinated brown rice suppress liver damage induced by carbon tetrachloride in rats 总被引:4,自引:0,他引:4
Extracts of Phellinus linteus (EPB), grown on germinated brown rice, protected rats from liver injury induced by carbon tetrachloride (CCl4). Peroxidation products in the liver were decreased to 10% by EPB. Catalase and superoxide dismutase activities were significantly decreased to 55% and 39% by CCl4 administration, but EPB blocked this effect, resulting in enzyme activities at control levels. Expression of cytochromeP450 2E1 (CYP2E1) protein was significantly decreased to 88% in CCl4-treated rats but remained at control levels when EPB was also administered. EPB did not affect the altered fatty acid composition induced by CCl4. The hepatoprotective effect of EPB may be mediated by EPB's prevention of CCl4-induced CYP2E1 degradation. 相似文献
980.
Kue Peng Lim Nicole Ai Leng Chun Siti Mazlipah Ismail Mannil Thomas Abraham Mohd Nury Yusoff Rosnah Binti Zain Wei Cheong Ngeow Sathibalan Ponniah Sok Ching Cheong 《PloS one》2014,9(8)
Regulatory T cells (Tregs), a subset of CD4+ T cells plays a pivotal role in regulating the immune system. An increase in Treg numbers enables cancer progression by dampening the immune system and allowing tumor cells to evade immune detection and destruction. An increase in Treg numbers and expression of inhibitory cytokines including TGF-β and IL-10 are mechanisms by which Tregs exert their immune suppressive function. However, the presence of Tregs and inhibitory cytokines in oral cancer patients is still unclear. In this study, the presence of circulating Tregs in 39 oral cancer patients and 24 healthy donors was examined by studying the presence of the CD4+CD25hiCD127low cell population in their peripheral blood mononuclear cells using flow cytometry. Serum levels of TGF-β and IL-10 were measured by ELISA. T cell subsets of OSCC patients were found to differ significantly from healthy donors where a decrease in CD8+ cytotoxic T cells and an increase in Tregs (CD4+CD25hiCD127low) were observed. Further, the ratio of CD8+ T cells/Tregs was also decreased in patients compared to healthy donors. The presence of Tregs was accompanied by a decrease in IL-10 but not TGF-β secretion in OSCC patients when compared to donors; in addition, the analysis also revealed that an increased presence of Tregs was accompanied by better patient survival. Amongst OSCC patients, smokers had significantly higher levels of TGF-β. It is apparent that the immune system is compromised in OSCC patients and the characterization of the Treg subpopulation could form a basis for improving our understanding of the perturbations in the immune system that occur during OSCC tumorigenesis. 相似文献