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991.
Lu Z Bohn J Rano T Rutkowski CA Simcoe AL Olsen DB Schleif WA Carella A Gabryelski L Jin L Lin JH Emini E Chapman K Tata JR 《Bioorganic & medicinal chemistry letters》2005,15(23):5311-5314
Efforts directed to identifying potent HIV protease inhibitors (PI) have yielded a class of compounds that are not only very active against wild-type (NL4-3) HIV virus but also very potent against a panel of PI-resistant viral isolates. Chemistry and biology are described. 相似文献
992.
Isolation and characterization of phenanthrene-degrading <Emphasis Type="Italic">Sphingomonas paucimobilis</Emphasis> strain ZX4 总被引:3,自引:0,他引:3
Phenanthrene-degrading bacterium strain ZX4 was isolated from an oil-contaminated soil, and identified as Sphingomonas paucimobilis based on 16S rDNA sequence, cellular fatty acid composition, mol% G + C and Biolog-GN tests. Besides phenanthrene, strain ZX4 could also utilize naphthalene, fluorene and other aromatic compounds. The growth on salicylic acid and catechol showed that the strain degraded phenanthrene via salicylate pathway, while the assay of catechol 2, 3-dioxygenase revealed catechol could be metabolized through meta-cleavage pathway. Three genes, including two of meta-cleavage operon genes and one of GST encoding gene were obtained. The order of genes arrangement was similar to S-type meta-pathway operons. The phylogenetic trees based on 16S rDNA sequence and meta-pathway gene both revealed that strain ZX4 is clustered with strains from genus Sphingomonas. 相似文献
993.
Neuronal migration and lamina-specific primary afferent projections are crucial for establishing spinal cord circuits, but the underlying mechanisms are poorly understood. Here, we report that in mice lacking Dcc (deleted in colorectal cancer), some early-born neurons could not migrate ventrally in the spinal cord. Conversely, forced expression of Dcc caused ventral migration and prevented dorsolateral migration of late-born spinal neurons. In the superficial layer of the spinal cord of Dcc-/- mutants, mislocalized neurons are followed by proprioceptive afferents, while their presence repels nociceptive afferents through Sema3a. Thus, our study has shown that Dcc is a key molecule required for ventral migration of early-born neurons, and that appropriate neuronal migration is a prerequisite for, and coupled to, normal projections of primary afferents in the developing spinal cord. 相似文献
994.
First report of a novel plant lysozyme with both antifungal and antibacterial activities 总被引:6,自引:0,他引:6
Wang S Ng TB Chen T Lin D Wu J Rao P Ye X 《Biochemical and biophysical research communications》2005,327(3):820-827
A novel lysozyme exhibiting antifungal activity and with a molecular mass of 14.4kDa in SDS-polyacrylamide gel electrophoresis was isolated from mung bean (Phaseolus mungo) seeds using a procedure that involved aqueous extraction, ammonium sulfate precipitation, ion exchange chromatography on CM-Sephadex, and high-performance liquid chromatography on POROS HS-20. Its N-terminal sequence was very different from that of hen egg white lysozyme. Its pI was estimated to be above 9.7. The specific activity of the lysozyme was 355U/mg at pH 5.5 and 30 degrees C. The lysozyme exhibited a pH optimum at pH 5.5 and a temperature optimum at 55 degrees C. It is reported herein, for the first time, that a novel plant lysozyme exerted an antifungal action toward Fusarium oxysporum, Fusarium solani, Pythium aphanidermatum, Sclerotium rolfsii, and Botrytis cinerea, in addition to an antibacterial action against Staphylococcus aureus. 相似文献
995.
Cytokine-induced stable neuronal differentiation of human bone marrow mesenchymal stem cells in a serum/feeder cell-free condition 总被引:11,自引:0,他引:11
The characteristics and multilineage differentiation potential of bone marrow mesenchymal stem cells (BM MSC) remain controversial. This study aimed to characterize human BM MSC isolated by plastic adherent or antibody selection and their neuronal differentiation potential using growth factors or chemical inducing agents. MSC were found to express low levels of neuronal markers: neurofilament-M, beta tubulin III, and neuron specific enolase. Under a serum- and feeder cell-free condition, basic fibroblast growth factor, epidermal growth factor, and platelet-derived growth factor induced neuronal morphology in MSC. In addition to the above markers, these cells expressed neurotransmitters or associated proteins: gamma-aminobutyric acid, tyrosine hydroxylase and serotonin. These changes were maintained for up to 3 months in all bone marrow specimens (N = 6). In contrast, butylated hydroxyanisole and dimethylsulfoxide were unable to induce sustained neuronal differentiation. Our results show that MSC isolated by two different procedures produced identical lineage differentiation with defined growth factors in a serum- and feeder cell-free condition. 相似文献
996.
Effects of elevated CO<Subscript>2</Subscript> and nitrogen on wheat growth and photosynthesis 总被引:1,自引:0,他引:1
M.?PalEmail author L.?S.?Rao V.?Jain A.?C.?Srivastava R.?Pandey A.?Raj K.?P.?Singh 《Biologia Plantarum》2005,49(3):467-470
The effects of nitrogen [75 and 150 kg (N) ha−1] and elevated CO2 on growth, photosynthetic rate, contents of soluble leaf proteins and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and nitrate reductase (NR) were studied on wheat (Triticum aestivum L. cv. HD-2285) grown in open top chambers under either ambient (AC) or elevated (EC) CO2 concentration (350 ± 50, 600 ± 50 μmol mol−1) and analyzed at 40, 60 and 90 d after sowing. Plants grown under EC showed greater photosynthetic rate and were taller and attained greater leaf area along with higher total plant dry mass at all growth stages than those grown under AC. Total soluble and Rubisco protein contents decreased under EC but the activation of Rubisco was higher at EC with higher N supply. Nitrogen increased the NR activity whereas EC reduced it. Thus, EC causes increased growth and PN ability per unit uptake of N in wheat plants, even if N is limiting. 相似文献
997.
998.
Zheng Guo Tianwen Zhang Xia Li Qi Wang Jianzhen Xu Hui Yu Jing Zhu Haiyun Wang Chenguang Wang Eric J Topol Qing Wang Shaoqi Rao 《BMC bioinformatics》2005,6(1):1-12
Background
Despite the continuous production of genome sequence for a number of organisms, reliable, comprehensive, and cost effective gene prediction remains problematic. This is particularly true for genomes for which there is not a large collection of known gene sequences, such as the recently published chicken genome. We used the chicken sequence to test comparative and homology-based gene-finding methods followed by experimental validation as an effective genome annotation method.Results
We performed experimental evaluation by RT-PCR of three different computational gene finders, Ensembl, SGP2 and TWINSCAN, applied to the chicken genome. A Venn diagram was computed and each component of it was evaluated. The results showed that de novo comparative methods can identify up to about 700 chicken genes with no previous evidence of expression, and can correctly extend about 40% of homology-based predictions at the 5' end.Conclusions
De novo comparative gene prediction followed by experimental verification is effective at enhancing the annotation of the newly sequenced genomes provided by standard homology-based methods. 相似文献999.
1000.