Physicochemical properties of an extracellular polysaccharide isolated from culture media of Bacillus amyloliquefaciens]

A new extracellular polysaccharide has been isolated by chromatography on anion exchanger of a fraction obtained from highly viscous culture media of Bacillus amyloliquefaciens. This polysaccharide is characterised by high molecular weight (1,000,000 dalton) and intrinsic viscosity (323 ml/g). It contains 24% neutral sugar (galactose and mannose 5:1), 35% glucuronic acid and 51.5% N-acetylhexosamines (N-actylglucosamine, N-acetylgalactosamine and N-acetylbacillosamine 6:9:1).     

Effects of glycolytic metabolites on preservation of high energy phosphate level and synaptic transmission in the granule cells of guinea pig hippocampal slices

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.     

Biosynthesis of benzylpenicillin by mycelial suspensions ofPenicillium chrysogenum

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.     

Further studies on gel filtration of urinary substances.

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.     

Extended and bent conformations of the mannose receptor family

In mammals, the mannose receptor family consists of four members, Endo180, DEC-205, phospholipase A₂ receptor and the mannose receptor. The extracellular domains of all these receptors contain a similar arrangement of domains in which an Nterminal cysteine-rich domain is followed by a single fibronectin type II domain and eight or ten C-type lectin-like domains. This review focuses on the threedimensional structure of the receptors in the mannose receptor family and its functional implication. Recent research has revealed that several members of this family can exist in at least two configurations: an extended conformation with the N-terminal cysteinerich domain pointing outwards from the cell membrane and a bent conformation where the N-terminal domains fold back to interact with C-type lectin-like domains at the middle of the structure. Conformational transitions between these two states seem to regulate the interaction of these receptors with ligands and their oligomerization. Received 25 October 2007; received after revision 23 November 2007; accepted 7 December 2007     

Further studies on gel filtration of urinary substances

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.     

Trypanosoma cruzi: metabolic labeling of trypomastigote sialoglycolipids

Trypomastigote forms (infective) of Trypanosoma 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.     

Isolation and characterization of a high-molecular-weight glycoprotein from the endometrium of porcine uteri

A novel glycoprotein was isolated from the endometrium of porcine uteri. This high-molecular-weight glycoprotein consisted of 25% of protein and 73% of carbohydrate. The carbohydrate composition was quite characteristic in that equimolar N-acetylglucosamine and galactose were major constituents. Its unique nature makes it distinguishable from hitherto-reported glycoproteins.     

Isolation and characterization of a high-molecular-weight glycoprotein from the endometrium of porcine uteri

Summary A novel glycoprotein was isolated from the endometrium of porcine uteri. This high-molecular-weight glycoprotein consisted of 25% of protein and 73% of carbohydrate. The carbohydrate composition was quite characteristic in that equimolar N-acetylglucosamine and galactose were major constituents. Its unique nature makes it distinguishable from hitherto-reported glycoproteins.     

Isolation and partial characterization of a phytotoxic glycoprotein from culture filtrates ofRhynchosporium secalis

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.     

Mannosylation of lipid and protein acceptors in sheep lung microsomes]

In Sheep lungs, we have shown that a mannosyl-transferase activity is involved at microsomal level. This enzymatic system is able to catalyze the incorporation of mannose from GDP-mannose into two different endogenous acceptors: lipids and proteins. The mannolipid has the properties of a mannosyl-phosphoryl-polyprenol. The kinetic studies of product biosynthesis demonstrate that no precursor-product relationship exists in this system; this is an original behaviour of the lung in glycosylation phenomenon.     

Enzymic 'imprinting' as the result of early postnatal administration of enzyme inducers to animals

Early postnatal treatment of rats or mice with different enzyme inducers (cortisol, galactose, steroid which induces mixed function oxidases) results in long-lasting changes in the activity of corresponding inducible enzymes.     

Characterization of the host-specific toxins produced byHelminthosporium sacchari,the causal organism of eyespot disease of sugarcane

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.     

Trypanosoma cruzi: metabolic labeling of trypomastigote sialoglycolipids

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.     

Enzymic ‘imprinting’ as the result,of early postnatal administration of enzyme inducers to animals

Summary Early postnatal treatment of rats or mice with different enzyme inducers (cortisol, galactose, steroid which induces mixed function oxidases) results in long-lasting changes in the activity of corresponding inducible enzymes.     

Inhibitory effect of galactose on hydrogen transfer in the hemolymph ofVespa orientalis

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.     

Galactose and leucine transport in the developing rat small intestine

Summary Jejunal transport of galactose and leucine was studied in 9-45-day-old rats by means of the everted sac technique. Maximum transport was observed in 9-10-day-old rats, but then decreased until the 22nd day, and remained unchanged from then on. There were no remarkable differences in the pattern of galactose and leucine transport over this period.     

In vivo study of the hypocalcemic, hypophosphoremic, hyperlipemic, and immunogenic activities of the oligopeptide fragment common to ACTH, alpha and beta MSH, and beta lipotropin]

The intravenous injection that was given to rabbits which consisted of 0,5 mg of a common heptapeptide to ACTH4-10, BETA MSH11-17 hormones, and to beta lipotropic47-53 hormone (beta LPH47-53) was followed at the end of an hour by an augmentation of 70% of total lipids, and at the end of two hours by a lowering of calcemia (around 27%) and of phosphoremia (20%). The injection of a tetrapeptide corresponding to only ACTH7-10 bound to a nitrobenzylhydralamin and in presence of a Freund adjuvants has provoked the formation of corresponding antibodies.     

Demonstration and characterization of mannosyl phosphoryl dolichol synthesized in the outer membrane of liver mitochondria]

There is in mitochondrial outer membrane a mannosyl-transferase which is able to catalyse the mannose transfer on a polyprenic acceptor, to give a mannosyl-phosphoryl-dolichol. This enzyme is stimulated by Mn2+, Mg2+ and dithiothreitol. It is inhibited by GDP, mersalyl and EGTA.