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121.
Yan-Ru Cao Yi Jiang Qian Wang Shu-Kun Tang Wen-Xiang He Quan-Hong Xue Li-Hua Xu Cheng-Lin Jiang 《Antonie van Leeuwenhoek》2010,98(3):389-394
A novel pink-coloured, non-spore-forming, non-motile, Gram-negative bacterium, designated YIM 48858T, is described by using a polyphasic approach. The strain can grow at pH 6.5–9 (optimum at pH 7) and 25–30°C (optimum at 28°C).
NaCl is not required for its growth. Positive for oxidase and catalase. Urease activity, nitrate reduction, starch and Tween
80 tests are negative reaction. 16S rRNA gene sequence similarity studies showed that strain YIM 48858T is a member of the genus Rubellimicrobium, with similarities of 96.3, 95.7 and 95.5% to Rubellimicrobium mesophilum MSL-20T, Rubellimicrobium aerolatum 5715S-9T and Rubellimicrobium
thermophilum DSM 16684T, respectively. Q-10 was the predominant respiratory ubiquinone as in the other members of the genus Rubellimicrobium. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphoglycolipid, glycolipid and the major fatty
acids were C18:1 ω7c, C16:0 and C10:0 3-OH, which are very different from the valid published species. The DNA G + C content
was 67.7 mol%. Both phylogenetic and chemotaxonomic evidence supports that YIM 48858T is a novel species of the genus Rubellimicrobium, for which the name Rubellimicrobium roseum sp. nov. is proposed. The type strain is YIM 48858T (=CCTCC AA 208029T =KCTC 23202T). 相似文献
122.
123.
Li NJ Zeng GM Huang DL Hu S Feng CL Zhao MH Lai C Huang C Wei Z Xie GX 《Bioresource technology》2011,102(17):8137-8142
The production of oxalate at different initial Pb2+ concentrations during solid-state fermentation of straw with Phanerochaete chrysosporium was investigated. It was found that the maximal peak value of oxalate concentration (22.84 mM) was detected at the initial Pb2+ concentration of 200 mg kg−1 dry straw, while the minimum (15.89 mM) at the concentration of 600 mg Pb2+ kg−1 dry straw, and at moderate concentration of Pb2+ the capability of oxalic acid secretion was enhanced. In addition, it was also found that more oxalic acid accumulation went together with better Pb2+ passivation effect and higher manganese peroxidase (MnP) activity. The present findings will improve the understandings of the interactions of heavy metals with white-rot fungi and the role of oxalate in lignin degradation system, which could provide useful references for more efficient treatment of Pb-contaminated lignocellulosic waste. 相似文献
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126.
de la Fuente C Wang L Wang D Deng L Wu K Li H Stein LD Denny T Coffman F Kehn K Baylor S Maddukuri A Pumfery A Kashanchi F 《Molecular and cellular biochemistry》2003,245(1-2):99-113
Adult T-cell leukemia (ATL) and HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) are associated with Human T-cell lymphotropic virus type 1 (HTLV-1) infection. The viral transactivator, Tax is able to mediate the cell cycle progression by targeting key regulators of the cell cycle such as p21/waf1, p16/ink4a, p53, cyclins D1-3/cdk complexes, and the mitotic spindle checkpoint MAD apparatus, thereby deregulating cellular DNA damage and checkpoint control. Genome expression profiling of infected cells exemplified by the development of DNA microarrays represents a major advance in genome-wide functional analysis. Utilizing cDNA microarray analysis, we have observed an apparent opposing and paradoxical regulatory network of host cell gene expression upon the introduction of DNA damage stress signal. We find the apparent induction of cell cycle inhibitors, and pro- as well as anti-apoptotic gene expression is directly linked to whether cells are at either G1, S, or G2/M phases of the cell cycle. Specifically, a G1/S block is induced by p21/waf1 and p16/ink4a, while pro-apoptotic expression at S, and G2/M is associated with caspase activation, and anti-apoptotic gene expression is associated with up regulation of Bcl-2 family member, namely bfl-1 gene. Therefore, the microarray results indicating expression of both pro- and anti-apoptotic genes could easily be explained by the particular stage of the cell cycle. Mechanism and the functional outcome of induction for both pathways are discussed. 相似文献
127.
Abstract This paper deals with two new species of Phasmatodea from the Xizang Aut. Reg. belonging to Phasmatidae and Heteronemiidae. Their comparisons with close species and figures of characteristics are given. 相似文献
128.
Milad Radiom Yong He Juan Peng-Wang Armelle Baeza-Squiban Jean-François Berret Yong Chen 《Biotechnology and bioengineering》2020,117(9):2827-2841
We report on the development of a new model of alveolar air–tissue interface on a chip. The model consists of an array of suspended hexagonal monolayers of gelatin nanofibers supported by microframes and a microfluidic device for the patch integration. The suspended monolayers are deformed to a central displacement of 40–80 µm at the air–liquid interface by application of air pressure in the range of 200–1,000 Pa. With respect to the diameter of the monolayers, that is, 500 µm, this displacement corresponds to a linear strain of 2–10% in agreement with the physiological strain range in the lung alveoli. The culture of A549 cells on the monolayers for an incubation time of 1–3 days showed viability in the model. We exerted a periodic strain of 5% at a frequency of 0.2 Hz for 1 hr to the cells. We found that the cells were strongly coupled to the nanofibers, but the strain reduced the coupling and induced remodeling of the actin cytoskeleton, which led to a better tissue formation. Our model can serve as a versatile tool in lung investigations such as in inhalation toxicology and therapy. 相似文献
129.
130.
Four new alkaloids, daphnioldhanins D-G (1-4, resp.), together with five known alkaloids, daphmacropodine (5), secodaphniphylline (6), deoxycalyciphylline B (7), deoxyisocalyciphylline B (8), and daphmanidin A (9), were isolated from the roots of Daphniphyllum oldhami. Their structures were elucidated on the basis of spectroscopic data and chemical methods. Compound 1 at 2.0 microM showed potent antioxidant activity against H(2)O(2)-induced impairment in PC12 cells. 相似文献