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41.
The protease problem in Neurospora. Variable stability of enzymes in aromatic amino acid metabolism.
S L Lampkin K W Cole A Vitto F H Gaertner 《Archives of biochemistry and biophysics》1976,177(2):561-565
A proteolytic activity isolated from Neurospora crassa is shown to be responsible for the variable stability observed in vitro for enzymes involved in aromatic amino acid metabolism. For example, the activity of kynurenine formamidase was insensitive to the action of this protease preparation over a 24-h period of incubation at 25 °C, whereas chorismate synthase, anthranilate synthase, kynureninase, and the five activities of the arom multienzyme system were inactivated during this time. Anthranilate synthase and two of the arom system activities (dehydroquinate synthase and shikimate kinase) were inactivated by the protease preparation within 2 h. Phenylmethanesulfonylfluoride and a specific proteolytic inhibitor from N. crassa prevented inactivation of these enzymes. Spontaneous loss of activity at 25 °C of purified samples of anthranilate synthase, dehydroquinate synthase and shikimate kinase was also prevented by the inhibitors. A method for purifying the inhibitor from N. crassa is described, and its use as a reagent in the analysis of proteolytic action is demonstrated. 相似文献
42.
A S Reddi W Oppermann L H Strugatz H S Cole R A Camerini-Davolos 《Hormones et métabolisme》1976,8(6):478-482
Serum alanine concentration was determined in nonpregnant and pregnant normal control Swiss albino (SA) and genetically diabetic KK mice. The serum alanine levels were significantly lower in nonpregnant KK than in nonpregnant SA mice. Fasting elicited hypoglycemia, hypoinsulinemia and hypoalaninemia in both groups of pregnant mice. Oral administration of alanine in nonpregnant and pregnant mice resulted in a significant rise in blood sugar levels within 15 min in both groups. However, the initial blood sugar response to oral alanine was greater in pregnant than in nonpregnant mice. This increase in blood sugar response to exogenous alanine appears to be mediated by glucagon. The data suggest that pregnancy elicits hypoglycemia, hypoinsulinemia and hypoalaninemia in both nondiabetic and diabetic mice. 相似文献
43.
Brenda F. Nesbitt P.S. Beevor R.A. Cole R. Lester R.G. Poppi 《Journal of insect physiology》1975,21(5):1091-1096
The female sex pheromones of the red bollworm moth, Diparopsis castanea, were isolated by solvent extraction of the terminal abdominal segments of the female moth followed by purification of the solvent extract by liquid-solid and gas chromatography. The pheromones were identified by gas chromatographic analysis, micro-ozonolysis, infra-red and mass spectroscopy, and comparison with synthetic material. The major pheromone was 9,11-dodecadien-1-yl acetate (80 : 20 trans : cis). Minor components identified were trans 9-dodecen-1-yl acetate, 11-dodecen-1-yl acetate, and dodecan-1-yl acetate. 相似文献
44.
John Cole 《Dialectical Anthropology》1975,1(1):239-249
Conclusions An even broader theoretical conclusion is in order. The term modernization has been enshrined in the value-free literature on development which the Western academy has created and supported. But the experience of Brasov, a local manifestation of Romanian development, makes it clear that modernization is by no means confined to Western assumptions, and that it always occurs in specific ways depending on the social situation of the society undergoing change, and on the political nature of the program being adopted. In short, socialist modernization in Romania is not parallel to modernization under capitalist auspices in analogous areas. 相似文献
45.
R H Salter T P Cole W G Scott-Harden T G Girdwood M A Reid 《BMJ (Clinical research ed.)》1975,2(5963):130-131
Analysis of the first year''s working of a combined gastroenterology clinic in a district hospital has shown that the major benefit was improved patient management. Hospital attendances were reduced, the diagnostic process accelerated, and unnecessary radiological investigations and surgical operations avoided. There were no obvious major disadvantages. 相似文献
46.
The erythropietin sensitivities of dissociated cell cultures and explanted fragments of fetal livers of congenitally anaemic SlJ/SlJ mice, and their normal littermates, have been compared. The erythropoietin responsiveness of SlJ/SlJ foetal liver cells is deficient in both types of culture. The maximum liver complement of erythroid colony forming cells (CFUe) occurs on the 16th day of development when ‘normal’ livers contain approximately 6 × 105 erythroid colony forming cells/liver. In SlJ/SlJ fetuses the maximum reached is only 1 × 105. Granulocyte-macrophage colony forming cells (CFUC) in SlJ/SlJ fetal livers are also reduced to approximately 60% of normal numbers. Erythroid colony forming cells are also reduced in the spleen and femoral bone marrow of SlJ/SlJ mice in the 2–3 days preceding birth. Granulocyte-macrophage colony forming cells are rare in the femoral marrow of pre-natal SlJ/SlJ mice, but their production in the SlJ/SlJ pre-natal spleen appears unaffected. 相似文献
47.
The enterotoxin gene (cpe) of Clostridium perfringens can be chromosomal or plasmid-borne 总被引:3,自引:0,他引:3
Emmanuel Cornillot † Brigitte Saint-Joanis Georges Daube Sei-ichi Katayama Per Einar Granum Bruno Canard ‡ Stewart T. Cole 《Molecular microbiology》1995,15(4):639-647
The location of the cpe gene, encoding the enterotoxin responsible for food poisoning in humans, has been studied in a series of enterotoxigenic Ciostridium perfringens strains by means of pulsed field gel electrophoresis of genomic DNA. The cpe gene was found at the same chromosomal locus in strains associated with food poisoning in humans and was shown to be linked to a repetitive sequence, the Hin dlll repeat, and an open reading frame, ORF3, that may be part of an insertion sequence. In contrast, when the strains originated from domesticated livestock cpe was located on a large episome where it was often close to a copy of the transposable element IS 1151. In these cases, the Hin dlll repeat was not linked to the cpe gene although this was generally preceded by ORF3. 相似文献
48.
Evangelia Stergiakouli Romy Gaillard Jeremy M. Tavaré Nina Balthasar Ruth J. Loos Hendrik R. Taal David M. Evans Fernando Rivadeneira Beate St Pourcain André G. Uitterlinden John P. Kemp Albert Hofman Susan M. Ring Tim J. Cole Vincent W.V. Jaddoe George Davey Smith Nicholas J. Timpson 《Obesity (Silver Spring, Md.)》2014,22(10):2252-2259
49.
50.