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971.
P.-S. Gao X.-Q. Mao M. Kawai T. Enomoto S. Sasaki O. Tanabe K. Yoshimura S. R. Shaldon Y. Dake H. Kitano P. Coull T. Shirakawa J. M. Hopkin 《Human genetics》1998,103(1):57-59
The gene encoding Clara cell-derived inflammatory molecule CC16 has been cited as a candidate gene for atopic asthma on chromosome
11q13. A genetic association study was performed with variants of the CC16 gene on chromosome 11q13 in relation to asthma
in British (n=275) and Japanese (n=300) populations. No significant association was found between asthma and CC16 genotypes, irrespective of atopic status in
these two populations. These data suggest that CC16 might not be the major locus for asthma on 11q13.
Received: 22 December 1997 / Accepted: 9 February 1998 相似文献
972.
Eiko Otaka Takuzi Itoh Syozo Osawa Kentaro Tanaka Mikio Tamaki 《Molecular & general genetics : MGG》1972,114(1):14-22
Summary Chromatographic analyses on a Dowex 50x8 column of tryptic digests of the mutationally altered 50-8 protein component from several erythromycin resistant (ery
r) mutants of Escherichia coli and Escherichia freundii have been performed. It was found that (1) the difference in the elution profile of the altered components detected with carboxymethyl cellulose column chromatography reflects the difference in their amino acid sequence, (2) the structural change(s) of the 50-8 protein from three E. coli ery
r mutants examined seems to exist only in the same single peptide fragment and (3) the primary structure of the 50-8(R) protein of E. freundii (ery
s: wild type) differs from that of E. coli Q13 (ery
s) and the structural change in 50-8(R) component of E. freundii caused by the ery
r mutation was found to take place in different peptide fragments from that in which the mutational change of the E. coli 50-8 component occurred. 相似文献
973.
Kentaro Tanaka Hiroshi Teraoka Mikio Tamaki Renkichi Takata Syozo Osawa 《Molecular & general genetics : MGG》1972,114(1):9-13
Summary An erythromycin resistant (ery
r) mutant of Escherichia coli Q13, QE107, was characterized by (1) the cross resistance of the cells to several macrolide antibiotics such as erythromycin, tylosin, spiramycin, oleandomycin and leucomycin, (2) the reduced affinity of its ribosomes to erythromycin and probably to the other macrolides mentioned above, (3) a low peptidyl transferase activity of its ribosomes and (4) an altered 50-8 protein of the 50s ribosomal subunits. These characters were always transferred together with the ery marker in the transduction experiments.Preliminary data of part of this work has been published (Tanaka, Teraoka, Tamaki, Watanabe, Osawa, Otaka and Takata, 1971). 相似文献
974.
The microdetermination of 2,3-diphosphoglycerate 总被引:1,自引:0,他引:1
A procedure for microestimation of 2,3-diphosphoglycerate, utilizing its role as coenzyme in the phosphoglycerate mutase reaction is described. The coenzymic activity was determined by assaying phosphoglycerate mutase polarimetrically without a coupled enzyme. This method is applicable to samples containing as little as 0.002 μmole of 2,3-diphosphoglycerate/ml. The content in various biological extracts was determined. 相似文献
975.
976.
977.
978.
Summary A sporadic translocation between two homologues of chromosome 15 was identified, by means of the quinacrine mustard fluorescence technique, in a phenotypically normal female infant with ventricular septal defect. Familial studies revealed certain individual variations regarding the intensely fluorescent centromeric regions in chromosomes 3 and 13, which appeared to be transmitted from the parents to offspring.
Contributions from the Chromosome Research Unit, Faculty of Science, Hokkaido University, Sapporo, Japan. Supported by grants, No. 584099, and No. 92035, from the Scientific Research Fund of the Ministry of Education. 相似文献
Zusammenfassung Eine sporadische Translokation zwischen zwei homologen Chromosomen Nr. 15 wurde mit Hilfe der Quinacrine-Mustard-Fluorescenztechnik bei einem weiblichen Säugling mit Ventrikelseptumdefekt festgestellt, der sonst phänotypisch normal war. Familienuntersuchungen ergaben gewisse individuelle Varianten der Zentromerregion in den Chromosomen 3 und 13, und es wurde eine Vererbung von den Eltern auf ihre Kinder festgestellt.Familienberatungen ergaben gewisse individuelle Variationen der intensiv fluorescierenden Zentromerregion.
Contributions from the Chromosome Research Unit, Faculty of Science, Hokkaido University, Sapporo, Japan. Supported by grants, No. 584099, and No. 92035, from the Scientific Research Fund of the Ministry of Education. 相似文献
979.
Further studies on the binding of vitamin B 12 to the cell wall of a B 12 -requiring Lactobacillus 总被引:1,自引:0,他引:1
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T Sasaki 《Journal of bacteriology》1972,109(1):169-178
The vitamin B(12)-binding property of Lactobacillus leichmannii ATCC 7830 has been studied. The organism could bind 0.52 mug of B(12) per mg of cells. With regard to the cellular site for B(12) accumulation, three-quarters of the B(12) bound to the cell was found in the crude cell wall fraction, and the remaining one-quarter was found in the particulate (ribosome) fraction. After receiving enzymatic treatments with ribonuclease, lipase, and trypsin, the wall fraction retained three-fifths of the initial B(12). The possibility of cross-contamination of the wall and particulate fractions was excluded by measuring the contents of ribonucleic acid and hexosamines in each fraction. The B(12)-binding activity of the wall was destroyed by pretreatment of the wall with pepsin, Pronase, or trypsin. However, once bound to the wall, the B(12) was not released by the same treatments. These facts suggest that B(12) is bound to a polypeptide in the wall on which these enzymes act and that, once bound, B(12) somehow inhibits the enzymatic actions as described earlier with L. delbrueckii no. 1. A B(12)-polypeptide complex was isolated by treatment with 0.2 n HCl from walls to which B(12) had been bound. The complex was then purified. The complex moves as a single band on polyacrylamide gel electrophoresis. Its molecular weight was estimated around 21,500 with microheterogeneity on a Sephadex G-75 column. The mode of B(12) binding was found to be similar to that of L. delbrueckii. 相似文献
980.