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941.
Park M Lee JH Shin H Kim M Choi J Kang DH Heu S Ryu S 《Applied and environmental microbiology》2012,78(1):58-69
Salmonella enterica and Escherichia coli O157:H7 are major food-borne pathogens causing serious illness. Phage SFP10, which revealed effective infection of both S. enterica and E. coli O157:H7, was isolated and characterized. SFP10 contains a 158-kb double-stranded DNA genome belonging to the Vi01 phage-like family Myoviridae. In vitro adsorption assays showed that the adsorption constant rates to both Salmonella enterica serovar Typhimurium and E. coli O157:H7 were 2.50 × 10−8 ml/min and 1.91 × 10−8 ml/min, respectively. One-step growth analysis revealed that SFP10 has a shorter latent period (25 min) and a larger burst size (>200 PFU) than ordinary Myoviridae phages, suggesting effective host infection and lytic activity. However, differential development of resistance to SFP10 in S. Typhimurium and E. coli O157:H7 was observed; bacteriophage-insensitive mutant (BIM) frequencies of 1.19 × 10−2 CFU/ml for S. Typhimurium and 4.58 × 10−5 CFU/ml for E. coli O157:H7 were found, indicating that SFP10 should be active and stable for control of E. coli O157:H7 with minimal emergence of SFP10-resistant pathogens but may not be for S. Typhimurium. Specific mutation of rfaL in S. Typhimurium and E. coli O157:H7 revealed the O antigen as an SFP10 receptor for both bacteria. Genome sequence analysis of SFP10 and its comparative analysis with homologous Salmonella Vi01 and Shigella phiSboM-AG3 phages revealed that their tail fiber and tail spike genes share low sequence identity, implying that the genes are major host specificity determinants. This is the first report identifying specific infection and inhibition of Salmonella Typhimurium and E. coli O157:H7 by a single bacteriophage. 相似文献
942.
Md. Abdullahil Baque Abdullah Elgirban Eun-Jung Lee Kee-Yoeup Paek 《Acta Physiologiae Plantarum》2012,34(2):405-415
The effect of initial sucrose concentration was investigated in root suspension cultures of Morinda citrifolia to improve root growth and secondary metabolites production, i.e. anthraquinone, phenolics and flavonoids. Besides, oxidative
stress level, antioxidant enzymes activity and membranes damage under different sucrose concentration were estimated. A 5%
sucrose supply was shown to be optimal for the production of root dry mass, but higher sucrose concentrations of 7–9% inhibited
the accumulation of root dry weight (DW). However, the maximum production of anthraquinone (251.89 g L−1 DW), phenolics (165.14 g L−1 DW) and flavonoids (163.56 g L−1 DW) were achieved at 1% sucrose-treated culture, which may be a source carbon skeletons for secondary metabolism. At the
same time was observed low oxidative damage, which could be associated with high levels of secondary metabolites and the increased
activity of catalase. Although, catalase (CAT) activity were stimulated at 7–9% sucrose-treated cultures, high accumulation
of hydrogen peroxide (H2O2) and peroxidation of lipid (MDA) was induced. The observed high activity of CAT and guaiacol peroxidase (G-POD) were not
sufficient enough to mitigate the toxic effect of H2O2. 相似文献
943.
944.
Shin SH Kim S Kim JY Song HY Cho SJ Kim DR Lee KI Lim HK Park NJ Hwang IT Yang KS 《Journal of bacteriology》2012,194(5):1266
This article reports on the full genome sequence of Paenibacillus terrae HPL-003, which is a gram-positive, endospore-forming, xylanase-producing bacterium isolated from soil found in forest residue on Gara Mountain. The strain HPL-003 contains 6,083,395 bp with a G+C content of 46.77 mol%, 2,633 protein-coding genes, and 117 structural RNAs. 相似文献
945.
A novel Gram-positive, aerobic, motile, hemolytic, endospore-forming and rod-shaped bacterium TW25T was isolated from a dead ark clam during a mass mortality event on the South coast of Korea. The strain grew optimally at
30°C, at pH 8–9, and with 1% (w/v) NaCl. The 16S rRNA gene sequence analysis indicated that strain TW25T was associated with the genus Ornithinibacillus and that it was most closely related to the type strain of Ornithinibacillus californiensis (98.5% similarity). The dominant cellular fatty acids were iso-C15:0, anteiso-C15:0 and C16:0. The peptidoglycan amino acid
type was A4β, containing l-ornithine and d-aspartic acid. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, four unidentified phospholipids, two unidentified
aminolipids and two unidentified lipids. The major respiratory quinone was menaquinone-7 (MK-7). The G + C content of genomic
DNA was 36.7 mol%. DNA–DNA hybridization experiments with related strains revealed lower than 11 ± 3% relatedness. Based on
this polyphasic taxonomic study, strain TW25T represents a novel species in the genus Ornithinibacillus, for which the name Ornithinibacillus scapharcae sp. nov. is proposed. The type strain is TW25T (=KACC 15116T = JCM 17314T). 相似文献
946.
Kim TY Shin SK Song MY Lee JE Park KS 《Biochemical and biophysical research communications》2012,417(3):1030-1034
Transient receptor potential melastatin 7 (TRPM7) channels are divalent cation-selective ion channels that are permeable to Ca(2+) and Mg(2+). TRPM7 is ubiquitously expressed in vertebrate cells and contains both an ion channel and a kinase domain. TRPM7 plays an important role in regulating cellular homeostatic levels of Ca(2+) and Mg(2+) in mammalian cells. Although studies have shown that the kinase domain of TRPM7 is required for channel activation and can phosphorylate other target proteins, a systematic analysis of intact TRPM7 channel phosphorylation sites expressed in mammalian cells is lacking. We applied mass spectrometric proteomic techniques to identify and characterize the key phosphorylation sites in TRPM7 channels. We identified 14 phosphorylation sites in the cytoplasmic domain of TRPM7, eight of which have not been previously reported. The identification of phosphorylation sites using antibody-based immunopurification and mass spectrometry is an effective approach for defining the phosphorylation status of TRPM7 channels. The present results show that TRPM7 channels are phosphorylated at multiple sites, which serves as a mechanism to modulate the dynamic functions of TRPM7 channels in mammalian cells. 相似文献
947.
Mycobacterium abscessus subsp. bolletii is an increasing cause of human pulmonary disease and infections of the skin and soft tissues. Consistent reports of human infections indicate that M. bolletii is a highly pathogenic, emerging species of rapidly growing mycobacteria (RGM). Here we report the first whole-genome sequence of M. abscessus subsp. bolletii BD(T). 相似文献
948.
949.
Satoshi N. Suzuki Masae I. Ishihara Masahiro Nakamura Shin Abe Tsutom Hiura Kosuke Homma Motoki Higa Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Motohiro Kawanishi Kazutaka Kobayashi Koichiro Kuraji Shigeo Kuramoto Takashi Masaki Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Tamotsu Sato Hirofumi Shibano Mitsue Shibata Maki Suzuki Atsushi Takashima Hiroshi Tanaka Masahiro Takagi Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2012,27(6):989-990
This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests. 相似文献
950.
Jung-Joon Park Key-Il Shin Joon-Ho Lee Sung Eun Lee Woo-Kyun Lee Kijong Cho 《Ecological Research》2012,27(1):1-13
Outlier detection and cleaning procedures were evaluated to estimate mathematical restricted variogram models with discrete
insect population count data. Because variogram modeling is significantly affected by outliers, methods to detect and clean
outliers from data sets are critical for proper variogram modeling. In this study, we examined spatial data in the form of
discrete measurements of insect counts on a rectangular grid. Two well-known insect pest population data were analyzed; one
data set was the western flower thrips, Frankliniella occidentalis (Pergande) on greenhouse cucumbers and the other was the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) on greenhouse cherry tomatoes. A spatial additive outlier model was constructed to detect outliers in both the
isolated and patchy spatial distributions of outliers, and the outliers were cleaned with the neighboring median cleaner.
To analyze the effect of outliers, we compared the relative nugget effects of data cleaned of outliers and data still containing
outliers after transformation. In addition, the correlation coefficients between the actual and predicted values were compared
using the leave-one-out cross-validation method with data cleaned of outliers and non-cleaned data after unbiased back transformation.
The outlier detection and cleaning procedure improved geostatistical analysis, particularly by reducing the nugget effect,
which greatly impacts the prediction variance of kriging. Consequently, the outlier detection and cleaning procedures used
here improved the results of geostatistical analysis with highly skewed and extremely fluctuating data, such as insect counts. 相似文献