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121.
122.
Guiqiu Chen Song Guan Guangming Zeng Xiaodong Li Anwei Chen Cui Shang Ying Zhou Huanke Li Jianmin He 《Applied microbiology and biotechnology》2013,97(7):3149-3157
Phanerochaete chrysosporium has been identified as an effective bioremediation agent for its biosorption and degradation ability. However, the applications of P. chrysosporium are limited owing to its long degradation time and low resistance to pollutants. In this research, nitrogen-doped TiO2 nanoparticles were loaded on P. chrysosporium to improve the remediation capacity for pollutants. The removal efficiencies were maintained at a high level: 84.2 % for Cd(II) and 78.9 % for 2,4-dichlorophenol (2,4-DCP) in the wide pH range of 4.0 to 7.0 in 60 h. The removal capacity of immobilized P. chrysosporium loaded with nitrogen-doped TiO2 nanoparticles (PTNs) was strongly affected by the initial Cd(II) and 2,4-DCP concentrations. The hyphae of PTNs became tight, and a large amount of crystals adhered to them after the reaction. Fourier transform infrared spectroscopy showed that carboxyl, amino, and hydroxyl groups on the surface of PTNs were responsible for the biosorption. In the degradation process, 2,4-DCP was broken down into o-chlorotoluene and 4-hexene-1-ol. These results showed that PTNs is promising for simultaneous removal of Cd(II) and 2,4-DCP from wastewater. 相似文献
123.
Xiaofei Ji Xinfeng Bai Zhe Li Sen Wang Zhiwei Guan Xuemei Lu 《Applied microbiology and biotechnology》2013,97(16):7317-7324
Cytophaga hutchinsonii is an aerobic cellulolytic gliding bacterium. The mechanism of its cell motility over surfaces without flagella and type IV pili is not known. In this study, mariner-based transposon mutagenesis was used to identify a new locus CHU_1797 essential for colony spreading on both hard and soft agar surfaces through gliding. CHU_1797 encodes a putative outer membrane protein of 348 amino acids with unknown function, and proteins which have high sequence similarity to CHU_1797 were widespread in the members of the phylum Bacteroidetes. The disruption of CHU_1797 suppressed spreading toward glucose on an agar surface, but had no significant effect on cellulose degradation for cells already in contact with cellulose. SEM observation showed that the mutant cells also regularly arranged on the surface of cellulose fiber similar with that of the wild type strain. These results indicated that the colony spreading ability on agar surfaces was not required for cellulose degradation by C. hutchinsonii. This was the first study focused on the relationship between cell motility and cellulose degradation of C. hutchinsonii. 相似文献
124.
Junlong Liu Guiquan Guan Zhijie Liu Aihong Liu Miling Ma Qi Bai Hong Yin Jianxun Luo 《Experimental parasitology》2013,133(2):217-221
Theileria sinensis was recently isolated and named as an independent Theileria species that infects cattle in China. To date, this parasite has been described based on its morphology, transmission and molecular studies, indicating that it should be classified as a distinct species. To test the validity of this taxon, the two internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene were cloned and sequenced from three T. sinensis isolates. The complete ITS sequences were compared with those of other Theileria sp. available in GenBank. Phylogenetic analyses based on sequence data for the complete ITS sequences indicate that T. sinensis lies in a distinct clade that is separate from that of T. buffeli/orientalis and T. annulata. Sequence comparisons indicate that different T. sinensis isolates possess unique sizes of ITS1 and ITS2 as well as species-specific nucleotide sequences. This analysis provides new molecular data to support the classification of T. sinensis as a distinct species from other known Theileria spp. based on ITS sequences. 相似文献
125.
Tong-Wei Guan Hui-Ping Zhao Zhen-Ming Che Xiao-Ping Zhang Li-Li Zhang 《Antonie van Leeuwenhoek》2013,104(5):787-792
A novel halophilic, filamentous actinomycete, designated TRM 4064T, was isolated from a hypersaline habitat in Sichuan Province, China. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of strain TRM 4064T showed that it was most closely related to Actinopolyspora mortivallis (99.1 % sequence similarity). The sequence similarities between strain TRM 4064T and other Actinopolyspora species with validly-published names were <97.0 %. However, it had relatively low mean values for DNA–DNA relatedness with the A. mortivallis DSM 44261T (23.2 %). Optimal growth occurred at 37 °C, pH 7.0 and in the presence of 13 % (w/v) NaCl. The whole-cell sugar pattern consists of xylose, glucose, ribose and arabinose. The predominant menaquinones are MK-10(H4) (38.2 %), MK-9(H4) (25.1 %), MK-9(H2) (28.6 %) and MK-8(H4) (7.3 %). The major fatty acids are anteiso-C17:0 (36.9 %) and iso-C17:0 (19.3 %). The diagnostic phospholipids detected were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI) and two unknown phospholipids. The G+C content of the genomic DNA of the type strain is 66.3 mol%. Strain TRM 4064T therefore represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora dayingensis sp. nov. is proposed. The type strain is TRM 4064T (= KCTC 19979T = CCTCC AA 2010010T). 相似文献
126.
Xu-Hong Gao Sheng Gao Yu Zhou Hui-Lin Guan Yun-Jiao Zhang Man Jia Hua-Wei Huang Dong-Xu Yang Wen-Jun Li Shu-Kun Tang 《Antonie van Leeuwenhoek》2013,103(1):207-215
A Gram-positive, moderately halotolerant, rod-shaped bacterium, designated YIM 94025T, was isolated from a soil sample from a salt lake in Xinjiang province, north-west China. Strain YIM 94025T was observed to grow at 25–45 °C (optimum 37 °C), 0–22 % NaCl (optimum 2–10 %) and pH 6.0–9.0 (optimum pH 8.0). Phylogenetic analyses based on 16S rRNA gene sequences revealed that the organism belongs to the genus Tenuibacillus and exhibited sequence similarity of 98.0 % to the closest type strain, Tenuibacillus multivorans AS 1.3442T. The predominant menaquinone was found to be MK-7; the cell-wall peptidoglycan diamino acid was meso-diaminopimelic acid; the polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, an unidentified phospholipid and an unknown lipid; and the major fatty acids were found to contain iso-C15:0, anteiso-C15:0 and iso-C16:0. The chemotaxonomic characteristics of strain YIM 94025T are consistent with those of the genus Tenuibacillus. The level of DNA–DNA relatedness value between YIM 94025T and T. multivorans AS 1.3442T was 36.6 ± 4.5 %. The G+C content of the strain YIM 94025T was determined to be 38.5 %. Based on the comparative analysis of physiological, biochemical and chemotaxonomic data, as well as DNA–DNA hybridization results, the isolate is considered to represent a novel species of the genus Tenuibacillus, for which the name Tenuibacillus halotolerans sp. nov., is proposed, with the type strain of YIM 94025T (=CCTCC AB 2012860T = KCTC 33046T). 相似文献
127.
Junhong Guan Han Li Tao Lv Duo Chen Ye Yuan Shengtao Qu 《Biochemical and biophysical research communications》2013
A mild cerebral ischemic insult, also known as ischemic preconditioning (IPC), confers transient tolerance to a subsequent ischemic challenge in the brain. This study was conducted to investigate whether bone morphogenetic protein-7 (BMP-7) is involved in neuroprotection elicited by IPC in a rat model of ischemia. Ischemic tolerance was induced in rats by IPC (15 min middle cerebral artery occlusion, MCAO) at 48 h before lethal ischemia (2 h MCAO). The present data showed that IPC increased BMP-7 mRNA and protein expression after 24 h reperfusion following ischemia in the brain. In rats of ischemia, IPC-induced reduction of cerebral infarct volume and improvement of neuronal morphology were attenuated when BMP-7 was inhibited either by antagonist noggin or short interfering RNA (siRNA) pre-treatment. Besides, cerebral IPC-induced up-regulation of B-cell lymphoma 2 (Bcl-2) and down-regulation of cleaved caspase-3 at 24 h after ischemia/reperfusion (I/R) injury were reversed via inhibition of BMP-7. These findings indicate that BMP-7 mediates IPC-induced tolerance to cerebral I/R, probably through inhibition of apoptosis. 相似文献
128.
Yee?Him Cheung Tenzin Gayden Philippe?M. Campeau Charles?A. LeDuc Donna Russo Van-Hung Nguyen Jiancheng Guo Ming Qi Yanfang Guan Steffen Albrecht Brenda Moroz Karen?W. Eldin James?T. Lu Jeremy Schwartzentruber David Malkin Albert?M. Berghuis Sherif Emil Richard?A. Gibbs David?L. Burk Megan Vanstone Brendan?H. Lee David Orchard Kym?M. Boycott Wendy?K. Chung Nada Jabado 《American journal of human genetics》2013,92(6):996-1000
Infantile myofibromatosis (IM) is the most common benign fibrous tumor of soft tissues affecting young children. By using whole-exome sequencing, RNA sequencing, and targeted sequencing, we investigated germline and tumor DNA in individuals from four distinct families with the familial form of IM and in five simplex IM cases with no previous family history of this disease. We identified a germline mutation c.1681C>T (p.Arg561Cys) in platelet-derived growth factor receptor β (PDGFRB) in all 11 affected individuals with familial IM, although none of the five individuals with nonfamilial IM had mutations in this gene. We further identified a second heterozygous mutation in PDGFRB in two myofibromas from one of the affected familial cases, indicative of a potential second hit in this gene in the tumor. PDGFR-β promotes growth of mesenchymal cells, including blood vessels and smooth muscles, which are affected in IM. Our findings indicate p.Arg561Cys substitution in PDGFR-β as a cause of the dominant form of this disease. They provide a rationale for further investigations of this specific mutation and gene to assess the benefits of targeted therapies against PDGFR-β in aggressive life-threatening familial forms of the disease. 相似文献
129.
Liwu Zhang Aiqing Li Xiaofei Wang Jiantang Xu Guangqing Zhang Jianguang Su Jianmin Qi Chunyun Guan 《Biochemical genetics》2013,51(9-10):800-810
Understanding genetic diversity is very useful for scientific utilization for breeding. In this study, we estimated the genetic distances in a panel of 84 kenaf accessions collected from 26 countries and regions using ISSR markers. The results of UPGMA analysis showed that kenaf germplasm had abundant genetic variation, with genetic dissimilarity coefficients ranging from 0.01 to 0.62. The in-group dissimilarity coefficient (0.29) was observed in 84 kenaf accessions, and all the accessions could be divided into three groups: cultivars (L1–1), relatively wild species (L1–2 and L1–3), and wild species (the others). Further in-group analysis in group L1–1 (0.19) revealed that the kenaf cultivars could be divided into five subgroups with distinct regional characteristics. It is imperative that genes be exchanged among all kinds of tested varieties from different origins. The results provide a useful basis for kenaf germplasm research and breeding. 相似文献
130.