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101.
Xiaoliang Liu Akemi Ota Michiko Watanabe Shigeharu Ueda Atsushi Saitoh Hideo Shinagawa Atsuo Nakata Takashi Kurimura Xiaoui Wang Yu Zhao Kiyoshi Kondo Jiro Seki Shinichi Miyake Nobuo Sakato Hajime Fujio 《Microbiology and immunology》1995,39(10):775-785
We investigated the murine antibody response to recombinant p17 (rp17) of human immunodeficiency virus type 1 (HIV-1) and the human antibody response directed to p17 in HIV-1 infection. Three large peptides covering residues 12-29, 53-87 and 87-115 of p17 were synthesized. The cysteine residues 57 and 87 of peptide 53-87 were reoxidized to form a disulfide bridge. Eighteen out of 19 murine monoclonal anti-rp17 antibodies had relatively high affinities (KA = 1.9 × 105?1.4 × 108 M?1) with one of the 3 p17 peptides in the liquid phase. Each monoclonal antibody reacted only with one particular peptide and had no reactivity with the other 2 p17 peptides. All the monoclonal antibodies reacted with rp17 in the liquid phase with a reasonable degree of affinity (KA = 2.0 × 105?1.8 × 107 M?1). Four HIV-1 carrier sera, which were positive in ELISA using rp17 as the antigen, reacted positively in an ELISA using 3 p17 peptides which were used to titrate murine monoclonal antibodies. Murine monoclonal antibodies having specificity for the 3 p17 peptides stained live HIV-1-infected cells by means of indirect membrane immunofluorescence, irrespective of their specificity. This suggests that the various portions of p17 (at least 3 regions of p17) were exposed on the surface of live infected cells, probably as short polypeptide chains. 相似文献
102.
Masahiro Goto Hiroshi Sumura Kojiro Abe Fumiyuki Nakashio 《Biotechnology Techniques》1995,9(2):101-104
Summary A novel preparation method for surfactant-coated enzymes has been developed using a W/O emulsion. The enzymatic activity of chymotrypsin in isooctane significantly increased with the coating of surfactants. The surfactant-coated chymotrypsin showed a high enzymatic activity for amidation, although powdered chymotrypsin did not show the activity. Further, the coated enzyme showed a remarkably high storage stability. 相似文献
103.
104.
The lipid phases of the thylakoid and cytoplasmic membranesfrom the blue-green alga, Anacystis nidulans, were studied bya spin-probe method using 2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxazolidinyloxyl.The thylakoid and cytoplasmic membranes of this alga were bothin the liquid crystalline state at growth temperature, and inthe phase separation state at about 0?C. The thylakoid membranesentered the phase separation state at a temperature higher thanthe cytoplasmic membranes. The lipid phase of the thylakoidmembranes from Anabaena variabilis was studied in a similarway, and these membranes were found also to undergo the phasetransition. The temperature for the onset of the phase separationand the fluidity of the membrane lipids of both algae dependedon the growth temperature of the culture. (Received April 9, 1984; Accepted June 1, 1984) 相似文献
105.
The rate assay of alpha-toxin assembly in membrane 总被引:1,自引:0,他引:1
Abstract A rapid and easy method to determine the 'rate' of the assembly of α-toxin from Staphylococus aureus in erythrocyte membrane was described. Upon addition of a small amount of α-toxins into erythrocyte suspension, absorbance at 700 nm decreased linearly after a short period of lag time. From the linear portion of the record the rate of the assembly of α-toxin was calculated. An optimum temperature and an optimum pH for the assembly of the toxin on erythrocyte membranes were found to be 25–30°C and pH 5. 相似文献
106.
Structure determination of a nucleoside Q precursor isolated from E. coli tRNA: 7-(aminomethyl)-7-deazaguanosine. 总被引:5,自引:3,他引:2 下载免费PDF全文
N Okada S Noguchi S Nishimura T Ohgi T Goto P F Crain J A McCloskey 《Nucleic acids research》1978,5(7):2289-2296
A precursor of modified nucleoside Q isolated from E. coli methyl-deficient tRNA was determined to be 7-(aminomethyl)-7-deazaguanosine. The structure was deduced by means of its chromatographic and electrophoretic mobilities, and UV and mass spectra, in addition to comparison with the synthesized authentic compound. The same molecule is also found in tRNA of an E. coli mutant selected for deficient synthesis of modified nucleosides. 相似文献
107.
Leukotriene A: stereochemistry and enzymatic conversion to leukotriene B 总被引:13,自引:0,他引:13
Olof Rådmark Curt Malmsten Bengt Samuelsson David A. Clark Giichi Goto Anthony Marfat E.J. Corey 《Biochemical and biophysical research communications》1980,92(3):954-961
Leukotriene A was assigned the structure 5(S)--5,6-oxido-7,9--eicosatetraenoic acid by the enzymatic conversion of a synthetic product of known stereochemistry into the naturally occurring isomer of 5(S),12(R)-dihydroxy-6,8,10,14-eicosatetraenoic acid in human polymorphonuclear leukocytes. 相似文献
108.
David A. Clark Giichi Goto Anthony Marfat E.J. Corey Sven Hammarström Bengt Samuelsson 《Biochemical and biophysical research communications》1980,94(4):1133-1139
A slow reacting substance, produced by murine mastocytoma cells, has been shown to have the structure 5(S)-hydroxy-6(R)--glutathionyl-7,9,11- leukotriene C, previously referred to as leukotriene C-2) by ultraviolet spectroscopy, amino acid analyses, lipoxygenase conversion and comparisions with a synthetic compound of known structure and stereochemistry. 相似文献
109.
Formation of bile acids in hemoglobin-free perfused rat livers 总被引:1,自引:0,他引:1
110.