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1.
Summary The generation of pyruvate and lactate inVespa orientalis hemolymph is prevented by the presence of galactose. The inhibitory effect is possibly produced by a competition for NAD and occurs in concentrations of 0.05 M.  相似文献   

2.
Summary Modeccin, the toxin ofAdenia digitata, agglutinates erythrocytes from several mammalian species. The haemagglutinating activity is enhanced by neuraminidase and is inhibited by galactose and by galactose-containing sugars.Acknowledgment. This research was supported by grants from the Consiglio Nazionale delle Ricerche, Rome, and by the Pallotti's legacy for cancer research.  相似文献   

3.
Receptor-mediated endocytosis byTetrahvmena pyriformis was studied using tetramethylrhodamine isothiocyanate-labeled concanavalin A (TRITC-Con A) with fluorescence and confocal microscopy. In the presence of insulin, or 24 h after insulin pretreatment (hormonal imprinting), the binding and uptake of TRITC-Con A increased when compared to controls, owing to the binding of TRITC-Con A to sugar oligomers of insulin recptors. Mannose inhibited the binding of Con A, thus demonstrating the specificity of binding. Histamine, a phagocytosis-promoting factor in mammals andTetrahymena, and galactose, did not influence the uptake of TRITC-Con A.  相似文献   

4.
Résumé Les auteurs ont étudié les effets des divers hydrates de carbone (glucose, fructose, mannose, galactose, xylose, arabinose, lactose, amidon et dextrine), du pyruvate, du lactate, de l'acétate, de l'huile d'arachide, etc. sur la biosynthèse de la pénicilline par les cellules lavées deP. chrysogenum.  相似文献   

5.
    
Summary -Galactosidase activity in intact cells of 21 species ofStreptomyces was measured using ONPG hydrolysis, without addition of a permeabilizing agent. Differences in the induction efficiency of ONPG-hydrolytic activity by lactose or galactose, which could have taxonomic implications, were observed among the species.  相似文献   

6.
Summary Agarose derivatized withp-nitrophenyl-N-acetyl--d-glucosamine was used for affinity chromatography for soluble galactosyltransferase from various sources. Moreover, this adsorbant acts as an acceptor for galactose when incubated with prepurified galactosyltransferase.This work was supported by a grant from the USPHS (grant No. 1 PO1 CA 14294-2).  相似文献   

7.
Résumé On a isolé du collagène naturel et polymère du tissu du manteau du calmarLoligo peallii par la méthode de Nishihara, les fibres présentant au microscope électronique une périodicité de 680 Å. Le collagène a une composition typique d'amino acides et contient l'hydrate de carbone dans une proportion restreinte; principalement sous forme de glucose et de galactose.  相似文献   

8.
Summary Trypomastigote forms (infective) ofTrypanosoma cruzi incorporate (3H)-palmitic acid and D-(3H)-galactose into glycolipids. Palmitic acid-labeled acidic glycolipids were partially hydrolyzed with neuraminidase. The labeling of these compounds when the intact cell surface was labeled with galactose oxidase plus NaB3H4 indicates the membrane location of the sialoglycolipids.This investigation received financial support from SECYT and CONICET to RML; CNPq, FINEP, and UNDP/World Bank/ WHOSSpecial Programme for Research and Training in Tropical Diseases to WC; and FAPESP to BZ and WC. ASC is a fellow from FAPESP.  相似文献   

9.
Summary The activities of-xylosidase,-xylanase and inulinase were demonstrated only in the tissues of the larval intestinal canal which also split galactose and arabinose from certain hemicelluloses and-galactan. Several other carbohydrases originating from microorganisms were also detected only in the content of the larval alimentary tract.

Ein Teil der Arbeit wurd am Institut für Obstbau der Biologischen Bundesanstalt Heidelberg ausgeführt.  相似文献   

10.
The organic matrix of four living cephalopod skeletons was extracted, purified, separated in a soluble and an insoluble fraction. These fractions were submitted to infrared analysis. After a light hydrolysis, their monosaccharide content was determined by HPAE-PAD. The results were treated by principal component analysis.Infrared analysis has been used to estimate the protein/sugar ratios and showed a high amount of chitin within the insoluble fractions. This was corroborated by their high content of glucosamine. The composition of soluble matrices appeared more heterogeneous: the general tendency is an increase of glucosamine from the most mineralized shell (Nautilus) to the non-mineralized one (Loligo), and a decrease in glucose and galactose. These data would be in agreement with the evolutionary tendency towards shell reduction and disappearance among cephalopods.  相似文献   

11.
The present study was undertaken to investigate whether neural activity of hippocampal slices can be preserved after replacingd-glucose with glycolytic intermediate metabolites such as lactate, pyruvate and citrate or with other sugars such as fructose, mannose, maltose, glucosamine, sucrose and galactose. As an index of neural activity, population spikes (PS) were recorded in the granule cell layers after electrical stimulation to the perforant path of guinea pig hippocampal slices. In addition, we determined the levels of ATP and creatine phosphate (CrP) in each slice after the replacement ofd-glucose with these substrates, and correlated it with the neural activity. Substrates other thand-glucose could not maintain the PS for even 20 min although the slices perfused with medium containing lactate, pyruvate, galactose, fructose and maltose maintained similar levels of ATP and CrP as in slices incubated in thed-glucose-containing medium. These results indicate thatd-glucose is essential for the preservation of synaptic activity in addition to its main role as the substrate for energy production to maintain the levels of high energy phosphates.  相似文献   

12.
Summary Investigation of the host-specific toxin complex fromH. sacchari has led to the isolation of 3 isomeric glycosidic components C39H64O22, each active at 2×10–11 moles. The 3 isomers consist of 4 galactose units linked to an aglycone residue C15H24O2.Acknowledgments. The Boyce Thompson-Cornell group thanks J.F. Rissler, University of Maryland, A.K. Bose, Stevens Institute of Technology, R. Barker and A. Serriani, Cornell University, and C. Grinnalds and J. Golay, Boyce Thompson Institute for help with various aspects of this work. Supported in part by a grant to V.M. from the US Department of Agriculture (8100720). The Zürich group thanks Dr G.A. Strobel, Department of Botany and Microbiology, Montana State University, Bozeman, for supplying a potent toxin-producing strain (M 36), a susceptible clone of sugarcane (51 NG 97), and a reference sample of helminthosporoside, Dr. K. Hostettmann and Mme M. Hostettmann-Kaldas, Pharmazeutisches Institut ETH Zürich, for assistance in developing the DCC separation and Sandoz A.G., Basel, for financial support.  相似文献   

13.
Summary Urine specimens from healthy children were concentrated and filtered through Sephadex G-100 and G-25. The eluate was recovered in fractions of 5 ml each. Total hexoses, galactose, total proteins and total uronic acids were determined on each fraction. Total hexoses and galactose were eluted in 6 distinct peaks. The uronic acid containing GAG were eluted in 4 small peaks on G-25 and 1 peak on G-100. This peak is eluted always with high amounts of galactose containing glycoproteins.This work was partially supported by research grants from the CONICET, República Argentina.  相似文献   

14.
Summary Rhynchosporium secalis (Oud.) Davis produces a phytotoxic compound with a mol. wt of 275×103 which is able to induce chlorotic symptoms in both susceptible and resistant barley leaves. Collectively, the data suggest that the toxin is a glycoprotein. Mild base treatment, by elimination, indicates that threonine and serine are involved in o-glycosidic linkages with the carbohydrate moiety. Sugar residues occur in the molecule in the ratio of mannose, rhammnose, galactose, glucosamine 13.6111.Acknowledgments. We acknowledge the assistance of Mr M. McNeil and P. Albersheim in doing the sugar analyses shown in this report. Financial support for this project was provided by a BARD grant 1-31-79, the French government, and the Montana Ag. Expt. Station.  相似文献   

15.
Summary Glucose inhibits the accumulation ofl-phenylalanine by rat intestinal slices during 45-minute incubations. In the presence of DNP (which alone abolishes all active transport), glucose, but not galactose, significantly stimulates amino-acid uptake. However, during short incubations, glucose inhibits the entry of phenylalamine into the tissue, both in the presence and absence of DNP.

Ce travail a été subventionné par le Fonds National Suisse. Nous tenons à remercier MllesC. Brandt etU. Pässler pour leur aide technique efficace.  相似文献   

16.
Summary Reevaluation of the previously proposed structure of helminthosporoside, a host-specific toxin fromHelminthosporium sacchari, reveals a sesquiterpenoid bis-digalactoside. The carbohydrate portion of the toxin was characterized by13C-NMR spectroscopy, methylation analyses, FD and FAB mass spectroscopy. The ring size and anomeric configuration of the galactose moieties were determined by utilizing a13C-NMR structural analysis method. A new partial structure is proposed.Acknowledgment. We extend special thanks to C.E. Costello, Department of Chemistry, M.I.T., Cambridge, MA, for FD mass spectral analyses, and to C.E. Ballou, Department of Biochemistry, University of California, Berkeley, CA, for FAB mass spectral analyses. We submit sincere appreciation to both V.N. Reihold, Harvard Medical School, Boston, MA, and P. Albersheim, Department of Chemistry, University of Colorado, Boulder, CO, for methylation analyses. We thank J.S. Frye at the Colorado State University Regional NMR-Center, funded by National Science Foundation grant No. DHE 78-18581, Department of Chemistry, Colorado State University, Fort Collins, Co, for high resolution CMR and NMR, and we are grateful to P.W. Jennings, Department of Chemistry, Montana State University, Bozeman, Mt, for total carbon analyses. This work was supported in part by a Herman Frasch Foundation grant to G.A. Strobel, by NSF grant PCM-78-22517, and funds from the Montana Agricultural Experiment Station. B.P. Mundy acknowledges the partial support of NSF (ISP-801149).  相似文献   

17.
Urine specimens from healthy children were concentrated and filtered through Sephadex G-100 and G-25. The eluate was recovered in fractions of 5 ml each. Total hexoses, galactose, total proteins and total uronic acids were determined on each fraction. Total hexoses and galactose were eluted in 6 distinct peaks. The uronic acid containing GAG were eluted in 4 small peaks on G-25 and 1 peak on G-100. This peak is eluted always with high amounts of galactose containing glycoproteins.  相似文献   

18.
In one strain of Chironomus thummi, galactose feeding of the larvae induced the appearance of 2 Balbiani-ring-like structures on salivary gland chromosomes I and II. This phenomenon may be related to the galactose induction of BR6 in C. pallidivittatus.  相似文献   

19.
Résumé Des poussins nourris avec une ration contenant plus de 10% de galactose développent des tremblements, des convulsions et meurent. Une dégénération des neurons et de l'oedéma péri-cellulaire se présente dans la zone des ganglions basals, dans la zone médullaire et dans les lobes optiques.

Supported by grant B 2951 (C1) from the National Institute of Neurological Diseases and Blindness, National Institutes of Health, United States Public Health Service.  相似文献   

20.
Summary The primary alcohol group on the carbon 6 of terminal galactosyl and N-acetylgalactosaminyl moieties of glycoproteins can be oxidized to an aldehyde by treatment with galactose oxidase. By reacting these aldehyde groups with14C-labeled sodium cyanide,14C-labeled cyanohydrin derivatives were obtained. Similarly, reduction of these aldehyde groups with tritiated sodium borohydride following standard procedures, yields3H-labeled glycoproteins.14C- and3H-labeled derivatives of asialofetuin and asialo ovine submaxillary mucin with high specific radioactivities were prepared using these procedures. Mixtures containing microgram amounts of14C- and3H-labeled glycoproteins were subjected to column chromatography and gradient ultracentrifugation and the position of the individual glycoproteins was determined by simultaneous counting for14C and3H. These experiments demonstrate the usefulness of this approach for comparative analytical studies using biological specimens available in minute quantities.  相似文献   

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