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Granulocyte-colony stimulating factor (G-CSF) is a glycoprotein hemopoietic growth factor which regulates the production of granulocytes and macrophages. Reversed-phase microbore high-performance liquid chromatography was employed to purify a number of tryptic and Staphylococcus aureus V8 proteinase peptides generated from approximately 400 pmol G-CSF purified from medium conditioned by lungs from mice previously injected with endotoxin. N-Terminal amino-acid sequence analyses were performed on the parent polypeptide and on four tryptic peptides and one Staphylococcus aureus V8 protease peptide, yielding 68 unique amino-acid assignments; this corresponds to approximately 38% of the molecule. 相似文献
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Desmethylnafoxidine aziridine: an electrophilic affinity label for the estrogen receptor with high efficiency and selectivity 总被引:1,自引:0,他引:1
Desmethylnafoxidine aziridine (Naf-Az), an affinity label for the estrogen receptor based structurally on the antiestrogen nafoxidine, has been prepared in unlabeled and in high specific activity, tritium-labeled form and has been evaluated for its apparent competitive binding, and time-dependent irreversible, covalent attachment to the estrogen receptor. Naf-Az was synthesized through a key 1,2-diaryl-3,4-dihydronaphthalene intermediate that was prepared from 6-methoxy-1-tetralone by two routes involving alternate strategies for arylation. Conversion of the diaryldihydronaphthalene to Naf-Az through a series of deprotection-activation reactions culminated in ethyleneimine displacement of a methanesulfonate. The tritium-labeled material was prepared by tritium-iodine exchange on an iodinated methanesulfonate precursor, followed by ethyleneimine displacement. Compared to our previously-prepared reagent tamoxifen aziridine (Tam-Az), Naf-Az has a higher apparent competitive binding affinity, and it reacts with the estrogen receptor in cytosol preparations and in intact MCF-7 breast cancer cells rapidly and with at least comparable efficiency and selectivity. SDS-polyacrylamide gel electrophoretic analysis confirms its selective labeling of the Mr 66,000 estrogen receptor. Naf-Az should prove to be useful in studies aimed at characterizing the properties and structure of estrogen receptors. 相似文献
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The hydrogen reactions of nitrogenase 总被引:2,自引:0,他引:2
Frank B. Simpson 《Physiologia plantarum》1987,69(1):187-190
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Streptococcus pyogenes type 12 M protein gene regulation by upstream sequences. 总被引:33,自引:7,他引:26 下载免费PDF全文
J C Robbins J G Spanier S J Jones W J Simpson P P Cleary 《Journal of bacteriology》1987,169(12):5633-5640
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C T Evans C J Corbin C T Saunders J C Merrill E R Simpson C R Mendelson 《The Journal of biological chemistry》1987,262(14):6914-6920
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Identification of an interleukin HP1-like plasmacytoma growth factor produced by L cells in response to viral infection 总被引:6,自引:0,他引:6
S Cayphas J Van Damme A Vink R J Simpson A Billiau J Van Snick 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(9):2965-2969
We have recently purified and partially sequenced a new T cell-derived lymphokine with growth factor activity for B cell hybridomas and plasmacytomas, which we named interleukin HP1 (HP1). Here we show that, in response to viral infection or after treatment with poly(rI).poly(rC), L cells produce a factor that is capable of supporting the in vitro growth and survival of HP1-dependent cell lines. Serologic and structural evidence is presented in favor of the identity between the fibroblast factor and HP1, demonstrating that non-T cells can make HP1-related molecules. 相似文献