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排序方式: 共有187条查询结果,搜索用时 46 毫秒
61.
62.
The lux genes from Photobacterium phosphoreum (NCMB844) have been cloned into Escherichia coli in a plasmid containing the T7-bacteriophage promoter. By specific expression in vivo under the T7 promoter, five structural genes (luxA-E) coding for the fatty acid reductase and luciferase polypeptides were identified as well as a new gene, designated as luxF, which codes for a 26kDa polypeptide. This new gene is located between luxB and luxE and thus disrupts the structural gene order of luxCDABE found in the Vibrio genus. The luxF gene and the protein it codes for have recently been identified in other Photobacterium species and so appears to be widely distributed within this genus. Nucleotide sequencing of the luxF gene has shown it to code for a protein homologous to the luciferase subunits, coded by the luxA and luxB genes. Although this gene is not necessary for light emission in all luminescent bacteria, it must play an essential role in the biochemistry, physiology, or ecology of the luminescent system in species of the Photobacterium genus. 相似文献
63.
Plasminogen activator-anti-human fibrinogen conjugate 总被引:1,自引:0,他引:1
C L Sevilla N H Mahle C M Boylan D M Callewaert 《Biochemical and biophysical research communications》1985,130(1):91-96
A covalent conjugate between the plasminogen activator urokinase and polyclonal rabbit anti-human fibrinogen has been formed using the heterobifunctional coupling reagent N-succinimidyl 3-(2-pyridyldithio) propionate. The resultant urokinase-anti-human fibrinogen conjugate was separated from unreacted material by gel filtration. The conjugate exhibited amidase activity against the small chromogenic substrate pyroglutamyl-glycyl-arginine-p-nitroanilide as well as plasminogen activator activity in an assay employing plasminogen and the plasmin substrate D-valyl-leucyl-lysine-p-nitroanilide. Retention of antibody specificity for fibrinogen was demonstrated using an enzyme linked immunoassay procedure. The conjugate was found to have greater stability in human plasma than unconjugated urokinase. 相似文献
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65.
Charlotte J. Sumner Constantin d’Ydewalle Joe Wooley Katherine A. Fawcett Dena Hernandez Alice R. Gardiner Bernadett Kalmar Robert H. Baloh Michael Gonzalez Stephan Züchner Horia C. Stanescu Robert Kleta Ami Mankodi David R. Cornblath Kevin B. Boylan Mary M. Reilly Linda Greensmith Andrew B. Singleton Matthew B. Harms Alexander M. Rossor Henry Houlden 《American journal of human genetics》2013
66.
Charlotte?J. Sumner Constantin d’Ydewalle Joe Wooley Katherine?A. Fawcett Dena Hernandez Alice?R. Gardiner Bernadett Kalmar Robert?H. Baloh Michael Gonzalez Stephan Züchner Horia?C. Stanescu Robert Kleta Ami Mankodi David?R. Cornblath Kevin?B. Boylan Mary?M. Reilly Linda Greensmith Andrew?B. Singleton Matthew?B. Harms Alexander?M. Rossor Henry Houlden 《American journal of human genetics》2013,93(5):976-983
67.
Carolyn B. Boylan Carol A. Bennett-Clarke Nicholas L. Chiaia Robert W. Rhoades 《Somatosensory & motor research》2013,30(1):52-60
Immunocytochemical and autoradiographic techniques were employed to determine the time course of expression of the serotonin (5-HT) transporter (SERT) on thalamocortical afferents in the rat's primary somatosensory cortex (S-I), and to correlate this expression to the transient vibrissae-related patterning of 5-HT immunostaining previously described. In additional in vivo and in vitro experiments, 5-HT and 3 H-5-HT were applied directly to the cortices of untreated and 5,7-dihydroxytryptamine-treated (5,7-DHT) rats in order to determine the period during which SERT functions on thalamocortical axons to take up 5-HT. In postnatal rats, SERT immunohistochemistry revealed a somatotopic patterning in S-I that persisted until P-15, which is 6 days after the disappearance of the vibrissae-related 5-HT immunostaining. 3 H-citalopram autoradiography revealed a vibrissae-related pattern in layer IV of S-I until at least P-30. Following destruction of raphe-cortical afferents with 5,7-DHT on the day of birth, this binding pattern remained visible until at least P-25, indicating that SERT located on thalamocortical axons is responsible for the 3 H-citalopram patterning observed in S-I. Tissue from 5,7-DHT-treated rats that had 5-HT applied directly to their cortices revealed a normal vibrissae-related pattern of 5-HT immunostaining in S-I at P-7 and P-11 but only a faint pattern at P-13 and none at P-14. In addition, 3 H-5-HT injected directly into S-I labeled layer IV barrels at P-6 and P-12 but not at P-18. The results of these experiments demonstrate that SERT is expressed by thalamocortical afferents and remains functional long after the vibrissae-related 5-HT immunostaining in cortex disappears. 相似文献
68.
AbstractAqueous low molecular weight organic carbon-14 (14C) substances can be formed by the oxidation of carbide and impurities within nuclear fuel cladding. During reprocessing and interim storage 14C-labeled organic compounds may leak to the shallow subsurface environments at nuclear facilities where denitrifying and iron reducing zones can exist. 14C-labeled organic compounds (acetate, formate, formaldehyde and methanol) were used as electron donors in microcosm experiments, under both denitrification and iron reduction, using glacial outwash sediments and groundwater composition representative of the Sellafield nuclear reprocessing site, UK. In denitrifying microcosms, <6% of the initial 14C-DOC remained 15?days after injection into the microcosm irrespective of the electron donor; with concurrent 14CO2 (g) production. Lack of removal in sterile controls suggests that 14C-organics were metabolized by microorganisms. Under iron-reducing conditions both 14C-carboxylates were removed from solution rapidly, but some formaldehyde and methanol remained in solution 32?days after injection into the microcosm so there is potential that a proportion of 14C-formaldehyde and 14C-methanol may persist for longer in subsurface environments. 相似文献
69.
Expanded GGGGCC hexanucleotide repeat in noncoding region of C9ORF72 causes chromosome 9p-linked FTD and ALS 总被引:3,自引:0,他引:3
DeJesus-Hernandez M Mackenzie IR Boeve BF Boxer AL Baker M Rutherford NJ Nicholson AM Finch NA Flynn H Adamson J Kouri N Wojtas A Sengdy P Hsiung GY Karydas A Seeley WW Josephs KA Coppola G Geschwind DH Wszolek ZK Feldman H Knopman DS Petersen RC Miller BL Dickson DW Boylan KB Graff-Radford NR Rademakers R 《Neuron》2011,72(2):245-256
70.
Nguyen KT Wu JC Boylan JA Gherardini FC Pei D 《Archives of biochemistry and biophysics》2007,468(2):217-225
Peptide deformylase (PDF, E.C. 3.5.1.88) catalyzes the removal of N-terminal formyl groups from nascent ribosome-synthesized polypeptides. PDF contains a catalytically essential divalent metal ion, which is tetrahedrally coordinated by three protein ligands (His, His, and Cys) and a water molecule. Previous studies revealed that the metal cofactor is a Fe2+ ion in Escherichia coli and many other bacterial PDFs. In this work, we found that PDFs from two iron-deficient bacteria, Borrelia burgdorferi and Lactobacillus plantarum, are stable and highly active under aerobic conditions. The native B. burgdorferi PDF (BbPDF) was purified 1200-fold and metal analysis revealed that it contains ∼1.1 Zn2+ ion/polypeptide but no iron. Our studies suggest that PDF utilizes different metal ions in different organisms. These data have important implications in designing PDF inhibitors and should help address some of the unresolved issues regarding PDF structure and catalytic function. 相似文献