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Mi-Seon Jung Xiao-Tian Quan Muhammad Zubair Siddiqi Qingzhen Liu Sang Yong Kim Ji-Hyang Wee Wan Taek Im 《Journal of microbiology (Seoul, Korea)》2018,56(10):706-712
Gram-positive, aerobic, non-motile, pale-yellow, and rodshaped bacterium, designated as Gsoil 188T, was isolated from the soil of a ginseng field in Pocheon, South Korea. A phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Brevibacterium and was most closely related to B. epidermidis NBRC 14811T (98.4%), B. sediminis FXJ8.269T (98.2%), B. avium NCFB 3055T (98.1%), and B. oceani BBH7T (98.1%), while it shared less than 98.1% identity with the other species of this genus. The DNA G + C content was 68.1 mol%. The predominant quinone was MK-8(H2). The major fatty acids were anteiso-C15:0 and anteiso-C17:0. The cell wall peptidoglycan of strain Gsoil 188T contained meso-diaminopimelic acid. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and an unidentified aminolipid. The physiological and biochemical characteristics, low DNA-DNA relatedness values, and taxonomic analysis allowed the differentiation of strain Gsoil 188T from the other recognized species of the genus Brevibacterium. Therefore, strain Gsoil 188T represents a novel species of the genus Brevibacterium, for which the name Brevibacterium anseongense sp. nov. is proposed, with the type strain Gsoil 188T (= KACC 19439T = LMG 30331T). 相似文献
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Orme CD Davies RG Olson VA Thomas GH Ding TS Rasmussen PC Ridgely RS Stattersfield AJ Bennett PM Owens IP Blackburn TM Gaston KJ 《PLoS biology》2006,4(7):e208
Large-scale patterns of spatial variation in species geographic range size are central to many fundamental questions in macroecology and conservation biology. However, the global nature of these patterns has remained contentious, since previous studies have been geographically restricted and/or based on small taxonomic groups. Here, using a database on the breeding distributions of birds, we report the first (to our knowledge) global maps of variation in species range sizes for an entire taxonomic class. We show that range area does not follow a simple latitudinal pattern. Instead, the smallest range areas are attained on islands, in mountainous areas, and largely in the southern hemisphere. In contrast, bird species richness peaks around the equator, and towards higher latitudes. Despite these profoundly different latitudinal patterns, spatially explicit models reveal a weak tendency for areas with high species richness to house species with significantly smaller median range area. Taken together, these results show that for birds many spatial patterns in range size described in geographically restricted analyses do not reflect global rules. It remains to be discovered whether global patterns in geographic range size are best interpreted in terms of geographical variation in species assemblage packing, or in the rates of speciation, extinction, and dispersal that ultimately underlie biodiversity. 相似文献
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Cheng ZJ Jiang YF Ding H Severson D Triggle CR 《Canadian journal of physiology and pharmacology》2007,85(3-4):404-412
In this study, we tested the hypothesis that spontaneously diabetic TallyHo (TH) mice, a novel polygenic model for type 2 diabetes, will exhibit endothelial dysfunction associated with an increased contribution from endothelium-derived contractile factors (EDCF). The cellular mechanisms underlying the increased contribution of EDCF were explored in 16 and 30-week-old male TH and age-matched male C57BL/6J mice (n=4-9). Blood glucose and serum lipid profiles were markedly increased in the TH mice. Superoxide generation, assessed with a lucigenin chemiluminescence assay, was markedly increased in the aortae of TH mice. Endothelium-dependent vascular relaxations and contractions to acetylcholine (ACh), but not endothelium-independent relaxations to sodium nitroprusside, were impaired and vascular contractions to phenylephrine were significantly enhanced in aortae from TH mice. Nomega-nitro-L-arginine methyl ester markedly increased the ACh-induced contractions in TH mice, whereas SQ29548, a thromboxane receptor antagonist, and cytochrome P450 (CYP) inhibitors 17-octadecynoic acid and sulfaphenazole, the latter being specific for CYP2C6 and 2C9, decreased and (or) normalized the contractile response to ACh in TH mice. The present study indicates that enhanced contribution of prostaglandin H2/thromboxane A2 receptor and CYP, likely CYP2C6 and 2C9, play a critical role in the pathogenesis of increased EDCF in the aortae of type 2 diabetic TH mice. 相似文献
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本文对山东省曲阜市1982-1994年二代棉铃虫发生动态的虫情与相应年份的气象资料进行了数量分析,应用Fuzzy优选识别原理,建立了二代棉铃虫发生动态的Fuzzy优选识别模式·对历史资料进行回代验证,其历史拟合率为 100%.书 1995,1996 两年的观测数据资料作为独立样本进行试报,预测结果与实际一致.本研究为农业害虫发生动态的预测预报提供了一种新的研究方法. 相似文献
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Synergistic interactions between Glomus mosseae and Bradyrhizobium japonicum in enhancing proton release from nodules and hyphae 总被引:1,自引:0,他引:1
Soybean (Glycine max L. Merr.) seedlings were inoculated with Glomus mosseae (GM) and Bradyrhizobium japonicum (BJ) together or separately to study the effect of interactions on net H+ effluxes of nodules or extraradical hyphae by in vivo vibrating electrode techniques. GM promoted three-fold the H+ effluxes of nodules on mycorrhizal lateral roots and BJ increased eight-fold the net H+ effluxes of hyphae developing in the vicinity of nodules on lateral roots. Increments in plant P content were positively
and linearly correlated with the net H+ efflux of nodules and hyphae. It is concluded that increased H+ effluxes of nodules resulted from enhanced nitrogenase activities induced by the presence of the AM fungus in lateral roots.
The results point to additive effects of interactions between mycorrhizal fungi and rhizobia in increasing the extent of acidification
of the “nodulesphere” and the hyposphere. 相似文献