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101.
H. Fujii S. Miwa S. Takegawa K. Takahashi A. Hirono T. Takizawa T. Morisaki H. Kanno T. Taguchi J. Okamura 《Human genetics》1984,66(2-3):276-278
Summary Two new glucose-6-phosphate dehydrogenase (G6PD) variants were discovered in Japan. The first, found in a 9-year-old male, was associated with chronic hemolysis and hemolytic crises after upper respiratory infections. The enzyme activity of the variant was 2.9% of normal. The patient's G6PD showed an increased utilization of substrate analogue, deamino-NADP, and thermal instability. The second variant occurred in a 7-year-old male with druginduced hemolysis. The main enzymatic characteristics were reduced enzyme activity, being 6.4% of normal, faster-thannormal anodal electrophoretic mobility, slightly high Michaelis constant for glucose-6-phosphate, thermal instability, and biphasic pH optima. Enzymatic properties of these variants allowed each to be distinguished from previously reported variants. The first variant was designated Gd (-) Gifu and the other, Gd (-) Fukuoka. 相似文献
102.
T. Takizawa H. Fujii S. Takegawa K. Takahashi A. Hirono T. Morisaki H. Kanno R. Oka H. Yoshioka S. Miwa 《Human genetics》1984,68(1):70-72
Summary A new glucose 6-phosphate dehydrogenase (G6PD) variant associated with chronic nonspherocytic hemolytic anemia was discovered in Japan. The patient showed hemolytic crises after upper respiratory infections. The enzyme activity was about 3.8% of the normal. The partially purified enzyme revealed slow anodal electrophoretic mobility, high Km NADP, marked thermal-instability, and increased affinity for a substrate analogue (deamino-NADP). A particular characteristic of this enzyme was a biphasic pH curve with a greatly increased activity at low pH values. From these results, this variant was clearly different from hitherto observed G6PD variants, and was designated G6PD Asahikawa. 相似文献
103.
Formation and characterization of antibody against 2''-(5"-phosphoribosyl)-5'' AMP, the monomer form of poly(adenosine diphosphate ribose). 总被引:1,自引:0,他引:1
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Specific antibody against 2'-(5"-phosphoribosyl)-5'AMP (PR-AMP), a monomer of poly(adenosine diphosphate ribose) (poly(ADP-Rib)), was produced by immunizing a rabbit with PR-AMP coupled to bovine serum albumin (BSA). Antibody against PR-AMP was purified 53-fold from serum by (NH4) 2SO4 precipitation, and BSA-Sepharose 4B, DEAE-cellulose and (PR-AMP)-BSA-Sepharose 4B column chromatographies. Inhibition experiments show that the adenine ring, 5'-phosphate residue and ribose-ribose bond of PR-AMP were essential for the antigenic determinant of PR-AMP. Anti PR-AMP antibody bound, not only with PR-AMP, but also with poly(ADP-Rib) of various chain lengths, while anti poly(ADP-Rib) antibody bound with poly(ADP-Rib) but not with PR-AMP. 相似文献
104.
105.
Two polypeptides associated with the ribonucleic acid polymerase core of Bacillus subtilis during sporulation. 总被引:8,自引:3,他引:5
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The ribonucleic acid (RNA) polymerase from log-phase and sporulating cells of Bacillus subtilis was analyzed to determine whether any structural changes occurred during sporulation. The elution pattern of RNA polymerase from a deoxyribonucleic acid (DNA)-cellulose column revealed that sporulating cells at stages III and IV contained a new RNA polymerase fraction in addition to the vegetative holoenzyme (alpha2betabeta'sigma). Stage III cells contained the vegetative holoenzyme and a new enzyme with the composition alpha2betabeta'delta1; the molecular weight of delta1 was 28,000. Stage IV cells contained the vegetative holoenzyme, the delta1-containing enzyme, and another enzyme with the composition alpha2betabeta'delta2. The delta2 factor had a molecular weight of around 20,000. The delta-containing enzymes have a higher affinity for the DNA-cellulose column and a higher specific activity on various templates than vegetative holoenzyme. The simultaneous appearance of these enzymes with vegetative holoenzymes in sporulating cells is consistent with the data found previously with DNA-RNA hybridization studies, which showed that sporulating cells contained both vegetative and sporulation messenger RNAs. 相似文献
106.
Effect of Macromolecular Synthesis on the Coordinate Morphogenesis of Polar Surface Structures in Caulobacter crescentus
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The Caulobacter polar surface structures (flagella, pili, and the deoxyribonucleic acid phage phiCbK receptors), which are expressed at proximal sites of swarmer cells in a coordinate manner (Shapiro, Annu. Rev. Microbiol., 30:377-407, 1976) could be blocked by a single mutation. The mutant C. crescentus CB13 ple-801 did not form these surface structures when grown at 35 degrees C. Upon shift down to 25 degrees C, the mutant cells initiated the formation of the surface structures. When mitomycin C was added to the mutant culture upon shift down from 35 to 25 degrees C, phiCbK receptor formation was inhibited to a minimal level. Rifampin and chloramphenicol completely inhibited phiCbK receptor formation when added to the mutant culture upon shift down. Deoxyribonucleic acid as well as ribonucleic acid and protein synthesis seem to be required for the formation of phiCbK receptors. Penicillin V also inhibited phiCbK receptor formation, indicating the involvement of cell wall synthesis. When the mutant CB13 ple-801 cells were shifted down briefly from 35 to 25 degrees C and then shifted up to 35 degrees C, flagella and phiCbK receptors were formed even at 35 degrees C to different extents depending on how long the cells were incubated at 25 degrees C. This formation of the surface structures at 35 degrees C was inhibited by rifampin. From these results, it appears that translation, assembly, or localization processes for the formation of the surface structures are not temperature sensitive at 35 degrees C in the pleiotropic mutant CB13 ple-801. The syntheses of deoxyribonucleic acid and the cell wall do not appear to be temperature sensitive either, since the mutant grows normally at 35 degrees C. It is suggested that there exists a regulatory step that commits the cells to initiate the synthesis of requisite ribonucleic acid for the formation of the polar surface structures. 相似文献
107.
The ionic requirement for generating action potentials in ventral longitudinal muscle fibers dissected from beetle larvae was examined by conventional electrophysiological techniques. Muscle fibers that generated only graded responses in physiological saline were able to generate an all-or-none action potential when the potassium permeability of the membrane was inhibited by tetraethylammonium+ added to the saline. The peak of the action potential thus elicited was intimately related to the external Ca++ concentration. The action potential was blocked by Co++ which is known as a competitive inhibitor of Ca-spikes. Neither tetrodotoxin (3 μM) nor a Na-free condition effectively blocked the generation of the action potential. Mg++ induced a shift in the peak of the action potential; this was, however, due to the stabilizing action of Mg++ but not due to the penetration of Mg++ through the muscle membrane. No action potential was elicited in the muscle fiber when immersed in a Ca-free, EGTA saline even when a high concentration of either Mg++, Na+, or tetraethylammonium+ was present. The action potential of the larval muscle fiber was thus concluded to be a Ca-spike, through the channel of which Na+ or Mg++ did not penetrate. 相似文献
108.
G6PD Ube, a glucose-6-phosphate dehydrogenase variant found in four unrelated Japanese families. 总被引:1,自引:0,他引:1
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A total of 6,120 Japanese males were screened for glucose-6-phosphate dehydrogenase deficiency (G6PD). Five cases with the deficiency were discovered. Two of them and an additional two cases have the same variant, G6PD Ube, characterized by moderate enzyme deficiency, fast moving enzyme activity on electrophoresis, high Ki Nadph, utilization of substrate analogues, kinetics, pH optima, and stability. This variant was distinguished for G6PD A- and from other Oriental variants by biochemical parameters. Differences in the frequency and type of the variants between southern Asia and Japan, suggest that the Japanese who have been isolated on islands where malaria is not endemic, may have developed their own variant traits. 相似文献
109.
Kentaro Yoshimura Hiroko Aiba Hiroshi Oya Yoshiro Fukuda 《Experimental parasitology》1980,49(3):339-352
The survival, growth, and egg-laying capacity of young adult Angiostrongylus cantonensis, surgically transferred from intracranial sites into pulmonary arteries, were studied. A variety of experimental animals (rats, guinea pigs, mice, and mastomys) were chosen as donor animals and as recipient hosts (rats, guinea pigs, and rabbits). These species were specifically chosen to span the spectrum of host permissiveness relative to worm development in an attempt to understand the mechanisms which underlie species-dependent resistance. Recipient animals were monitored not only for the development of parasites per se but also for antibody production and histopathologic changes. The results indicated that these procedures were technically feasible, with good worm development following intra-rat transfers, as early as 15 days after initial exposure. Studies were performed to analyze the constraints of development both on initial, i.e., prelung and subsequent i.e., postlung development. When worms were obtained from permissive species such as rat or mastomys, transfer into rats resulted in good growth and development; however, worms which developed initially in exposed mice or guinea pigs developed less well in the rat. Conversely, worms which developed initially in permissive host such as the rat, when transferred into a variety of less permissive hosts such as the guinea pig and rabbit, apparently did not survive and caused significant morbidity and mortality within the nonpermissive host. Histopathologic evaluation revealed a strong eosinophilic perivascular and peribronchiolar infiltration as well as granulomatous reactions surrounding the worms in the lungs of recipient guinea pigs and rabbits, changes not observed in the lungs of permissive rat recipients. As reaginic antibody responses were also more prominent in nonpermissive than in permissive animals, it is possible that IgE responses may be more directly related to the phenomenon of morbidity and/or permissiveness than are other aspects of immune response. In support of this contention was the finding of nearly equivalent hemagglutinating antibody production between permissive rats and nonpermissive guinea pigs and rabbits. 相似文献
110.
Application of jackknife procedures to inter-experiment comparisons of parameter estimates for the Michaelis-Menten equation. 总被引:1,自引:0,他引:1
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The jackknife procedure is introduced as a means of making comparisons among Michaelis-Menten parameter estimates for six different experimental conditions. In addition to providing a solution to the general inter-experimental comparison problem, the jackknife procedure will provide valid parameter estimates even when some of the assumptions usually required for statistical analysis are violated, e.g., the random errors are not normally distributed and the variances are not homogeneous. Other recent variations of the jackknife have also been introduced and briefly investigated: (i) the linear jackknife, which is more efficient computationally, and (ii) the weighted jackknife, which reduces the influence of design points (substrate concentrations) that have an excessive influence on the precision of parameter estimates. 相似文献