[Polysaccharides of the fungus Cunninghamella japonica mycelium].

Preliminary data on the polysaccharide composition of mycelium of the submerged grown fungus Cunninghamella japonica (synonymous with C. echinulata) were obtained. Mild acid hydrolysis of the mycelium led to formation of glucose, mannose and galactose, whereas acid treatment under drastic conditions afforded glucosamine as the hydrolysis product of chitin and chitosan, the summary content of both glucosaminoglycans being estimated as about 35%. Sequential treatment of the mycelium with hot water, 2% aqueous NaOH and 10% AcOH gave rise to several polysaccharide fractions, which were characterized by their monosaccharide composition. The yield ofchitosan extracted by AcOH was negligible. Additional purification of the fraction obtained by the action of alkali afforded a polysaccharide preparation, which was shown to be a linear (1-->3)-alpha-D-glucopyranan according to the data of chemical methods of structural analysis and NMR spectroscopy. It was concluded that Cunninghamella japonica differs from several other known representatives of Mucorales by the presence of this alpha-D-glucan, as well as by low content of chitosan and polyuronides.

[Polysaccharide composition of mycelium and cell walls of the fungus Penicillium roqueforti].

Preliminary data on the polysaccharide composition of mycelium and cell walls of the submergedly grown fungus Penicillium roqueforti were obtained. Mild acid hydrolysis of mycelium and cell walls led to formation of glucose, mannose and galactose, whereas acid treatment under drastic conditions afforded glucosamine as the hydrolysis product of chitin, which content in the cell walls was estimated as 19%. Sequential treatment of the mycelium with hot water and 1 M NaOH at room temperature gave rise to several polysaccharide fractions, which were characterized by their monosaccharide composition. The main fraction obtained by the action of alkali, according to NMR spectroscopy, mass spectrometry and chemical methods of structural analysis data, is a linear alpha-D-glucopyranan containing blocks of (1 --> 3)-linked glucose residues interconnected by (1 --> 4)-linkages. Water-soluble polysaccharides contained linear blocks of (1 --> 5)-linked beta-galactofuranose residues, probably connected with a mannan core. The data obtained may be important for chemotaxonomy of the genus Penicillium.

[A highly branched storage polyglucan in the thermoacidophilic red microalga Galdieria maxima cells].

The thermoacidophilic red alga Galdieria maxima is capable of heterotrophic growth. The content of carbohydrates in H. maxima grown heterotrophically increases by a factor of 4, reaching as much as 60% of cell dry weight. The increase in the level of carbohydrates in cells is due to accumulation of a storage alpha-glycan. According to a specific cleavage to glucose catalyzed by amyloglucosidase and the high positive specific optical rotation characteristic of polyglucans, this polysaccharide can be classified as a floridean starch. The data of 1H NMR spectroscopy and the results of methylation showed that the average length of the unbranched regions of the polysaccharide molecule is six to seven glucose residues. The degree of branching of the starch molecule of G. maxima is greater than that of storage polysaccharides of other red algae, glycogens of yeast, and phytoglycogens of cyanobacteria.

[Polar components of Black sea seaweed Colpomenia peregrina (Sauv.) Hamel]. / Poliarnye komonenty chernomorskoi buroi vodorosli Colpomenia peregrina (Sauv.) Hamel.

GC-MS of trimethylsilyl derivatives of the compounds present in the butanolic extract of biomass of brown seaweed Colpomenia peregrina from the Black Sea aided in identification of 24 components, including aliphatic hydroxy and keto and aromatic acids, glycerol, mannitol, floridoside, and monosaccharides. The polysaccharide composition of the biomass was also studied, with high sodium alginate and laminaran contents and a comparatively low level of fucoidan being revealed. The polysaccharides were isolated from the biomass by fractional extraction and purified by precipitation or ion exchange chromatography. The structures of alginic acid and laminaran were deduced from 13C NMR spectra and confirmed, in the case of laminaran, by methylation analysis. The sodium alginate was shown to contain more guluronic (G) than mannuronic acid (M) residues, the M/G ratio being 0.48. Laminaran was demonstrated to be a beta-glucan with 1-->3 linkages in its backbone and 1-->6 linkages in its branching points, which is characteristic of brown algae. Fucoidan turned out to be a complex heteropolysaccharide containing, in addition to fucose and sulfate, other neutral monosaccharides and uronic acids. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 2; see also http://www.maik.ru

Plasticity of social behavior in Drosophila.

This article presents results obtained from studies of the plasticity of changes in social behavior in Drosophila (interactions between individuals in groups) in conditions of homo- and heterogeneous environments. This is the first report of data illustrating self-starting acquisition by female Drosophila of a classical conditioned reflex to contextual factors signaling possible threats from other individuals and blocking the initiation of activity. A previously described operant conditioned reflex also helped flies avoid aggression from other individuals and make more efficient use of food resources by decreasing the initially high level of activity. Classical conditioning had the effect that the fly did not need to repeat acquisition of the conditioned reflex each time: when placed into an analogous situation, the fly's activity automatically decreased as a result of exposure to the conditioned stimulus, i.e., contextual factors.

[Polar constituents of the ascidia Botryllus schlosseri]. / Poliarnye komponenty astsidii Botryllus schlosseri.

Eighteen compounds were identified by GC-MS of their trimethylsilyl derivatives in n-butanolic extract from the biomass of Botryllus schlosseri. Three of them, 5-oxoproline, 5-hydroxyhydantoin, and kinurenic acid, were found in marine invertebrates for the first time. In addition to cellulose, the biomass was also shown to contain complex water-soluble sulfated polysaccharides. These were extracted and fractionated, and sulfate content and monosaccharide composition were determined in the fractions; fucose, xylose, galactose, mannose, glucose, glucosamine, galactosamine, and uronic acids were found. Unlike several other tunicate species, Botryllus schlosseri does not seem to contain any simple galactan sulfate.

[Algae polysaccharides. 55. Polysaccharide composition of some brown Kamchatka algae]. / Polisakharidy vodoroslei. 55. Polisakharidnyi sostav nekotorykh burykh vodoroslei Kamchatki.

A new spectrophotometric procedure was developed for the quantitative determination of fucoidan and alginic acid and used for their analysis in extracts from biomass of 17 species of brown algae collected in coastal waters of the Kamchatka peninsula. In addition, neutral monosaccharides and mannitol were determined in the hydrolysis products of the alga biomass samples. The polysaccharide composition was shown to substantially depend on the algal species. The alginic acid content was maximal in the Alaria marginata blades; all the other representatives of the order Laminariales are also useful sources of the polysaccharides. At the same time, the fucoidan content is rather low in Laminariales. The highest content of fucoidan was found in Saundersella simplex, but Chordaria flagelliformis and Fucus evanescens are more practical fucoidan sources; the available supplies and the sugar composition make the latter alga the most suitable for the complex processing to prepare mannitol, fucoidan, and alginic acid.

[Plasticity of the social behavior in Drosophila]. / Plastichnost' sotsial'nogo povedeniia u drozofily.

Original data illustrate self-starting classical conditioning to environmental factors in Drosophila, the factors serving as signals of a possible threat from other individuals and blocking initiation of activity. Instrumental conditioning resulting in reduction of an initially high level of activity in the group situation, helps a fly to avoid aggression from other flies and to use the food resources more efficiently. Classical conditioning makes it unnecessary for a fly to learn this instrumental task again and again: being faced with an analogous situation the fly automatically decreases its activity following presentation of the conditioned stimuli or the specific environment.

[Gangliosides with 8-O-methyl-N-glycolylneuraminic acid and N-acetylgalactosamine from the star fish Asterias rathbuni]. / Gangliozidy s 8-O-mitil-N-glikolilneiraminovoi kislotoi i N-atsetilgalaktozaminom iz morskoi zvezdy Asterias rathbuni.

The structure of gangliosides isolated from the liver of starfish Asterias rathbuni was established by chemical methods, mass spectrometry, and enzymic hydrolysis with a neuraminidase. The major ganglioside was found to be a disialoganglioside with two 8-O-methyl-N-glycolylneuraminic acid residues bound with an N-acetylgalactosamine residue: 8-O-Me-NeuGc alpha 2-3 (8-O-Me-NeuGc alpha 2-6)GalNAc beta 1-3Gal beta 1-4Glc beta 1-1 Cer. Its lipid part contains unsubstituted higher fatty acids (mainly palmitic and stearic) and sphingosines (for the most part C20 and C22). The minor ganglioside fraction consists of two monosialogangliosides the carbohydrate chains of which differed only in the position of the terminal 8-O-methyl-N-glycolylneuraminic acid residue in the N-acetylgalactosamine moiety: 8-O-Me-NeuGc alpha 2-3GalNAc beta 1-3Gal beta 1-4Glc beta 1-1 Cer and 8-O-Me-NeuGc alpha 2-6GalNAc beta 1-3Gal beta 1-4Glc beta 1-1 Cer. The higher fatty acid composition of the minor gangliosides was determined too.

[The reciprocal training of Drosophila individuals in a group situation by the trial-and-error method]. / Vzaimoobuchenie osobei drozofily v gruppovoi situatsii metodom prob i oshibok.

In the group situation, fruit flies try to avoid conflicts in which they kick each others. At first they attempt to escape from each other thus increasing run frequency as compared with control solitary individuals, but shortly terminate runs in order to prevent collisions. Motoric activity and conflict frequency during encounters are high in such situations. From the very beginning, probability of transition from activity to direct contact is higher than that from rest to contact or from preening to contact. Therefore, during the first 5 minutes a fly learns to increase interval between runs using the trial-and-error method. Besides abrupt decreasing of number of collisions and activity of flies in group as compared with control, operant training leads to formation of passive aggregations, because closely situated flies avoid to display activity. A new behavior reaction is developed, as well, namely immobile fly initiate preventive touches by legs. Such training is adaptive because in the natural aggregations of flies on fermented fruits it increases aggressive activity decreasing thus raising efficiency of feeding on a common substrate.

[Ganglioside GM3 from horse erythrocytes: structure and effect on cell proliferation]. / Gangliozid GM3 iz éritrotsitov loshadi: struktura i vliianie na proliferatsiiu kletok.

An increase of the mouse fibroblast proliferation by ganglioside GM3 from equine erythrocytes is described. The structure of GM3 has been established on the basis of chemical methods, enzymatic degradation, GC-MS, as well as plasma desorption mass spectrometry and HPLC of 9-anthrylmethyl esters of gangliosides to characterize the long-chain base composition. The oligosaccharide moiety includes an N-glycolylneuraminic acid residue, whereas the main components of the lipid moiety are 20:1 sphingosine and 24:0 fatty acids.

Gangliosides of the starfish Aphelasterias japonica, evidence for a new linkage between two N-glycolylneuraminic acid residues through the hydroxy group of the glycolic acid residue.

Mono- and disialogangliosides containing glucose, galactose and sialic acids were isolated from the total lipid extract of hepatopancreas of the starfish Aphelasterias japonica. Their structures were elucidated by total and partial acid hydrolysis, trideuteriomethylation analysis, neuraminidase treatment, chromium trioxide oxidation, methanolysis and periodate oxidation. The monosialoganglioside was identified as 8-O-methyl-N-glycolylneuraminosyl-alpha-(2-3)-galactosyl-beta-(1- 4)-glucosyl-beta-(1-1)-ceramide. The disialoganglioside has the additional N-glycolylneuraminic acid or its 8-O-methyl derivative residue at the subterminal position to which the terminal sialic acid residue is linked through the hydroxy group of the glycolic acid unit. The long-chain bases were found to be mixtures of phytosphingosines with both branched and linear chains, and the fatty acids were shown to be mixtures of normal and alpha-hydroxy fatty acids, the latter amounted to about 90% of the fatty-acid mixtures. The composition of the lipid moieties of the gangliosides was determined by GLC and GLC-MS.

The influence of serotonin and p-chlorophenylalanine on locomotor activity of Drosophila melanogaster.

Two hours after injection of serotonin into 3-day-old virgin females of Drosophila melanogaster, a significant dose-dependent increase in locomotor activity was observed. Since this stimulating effect can be produced either by serotonin or by some of its derivatives that might have formed during these two hours, the fate of injected [3H]-serotonin in the organism of Drosophila was traced by means of thin layer chromatography. The only metabolite found appeared to be N-acetylserotonin. Its formation was rather intense immediately after injection of [3H]-serotonin, and its excretion was rapid enough to make it undetectable at the end of the second hour, when more than 50% of the injected [3H]-serotonin still remained and was being absorbed by tissues. Thus, the increase in locomotor activity observed two hours after injection should be wholly attributed to serotonin, while the rather long latency might be related to some effect of N-acetylserotonin. p-Chlorophenylalanine, an inhibitor of tryptophan-5-hydroxylase, both injected or administered with food, led to increases in locomotor activity level and to some decreases in serotonin content in the heads of flies. The effect of p-chlorophenylalanine on locomotor activity in Drosophila seems to be non-specific in relation to serotoninergic mechanisms of its regulation.

A novel sialoglycolipid from hepatopancreas of the starfish Patiria pectinifera.

An unusual sialoglycolipid containing D-glucose, D-galactose, L-arabinose and N-acetylneuraminic acid was purified from the total lipid extract of hepatopancreas of the starfish Patiria pectinifera. The structure of the sialolipid was studied by total and partial acid hydrolysis, methanolysis, periodate oxidation, methylation, chromium trioxide oxidation and enzymatic hydrolysis. The oligosaccharide chain of the sialolipid is branched: N-acetylneuraminic acid is located in the inner part of the carbohydrate chain; the arabinose residues are in furanose forms and are located at the non-reducing ends of the carbohydrate chain. The long-chain bases are C16-, C17- and C18-phytospingosines with both branched and normal chains. Only alpha-hydroxy fatty acids are found, C22-, C23- and C24-alpha-hydroxy fatty acids represent approx. 95% of the total fatty acids.

Isolation and structural studies of a sulfated sialosphingolipid from the sea urchin Echinocardium cordatum.

Three sialosphingolipids have been isolated from a lipid extract of gonads of the sea urchin Echinocardium cordatum by partition dialysis and DEAE-cellulose column chromatography. The structure of the sialosphingolipid containing sulfate group has been established. On the basis of the results of total and partial acid hydrolysis, methanolysis, methylation, periodate oxidation and enzymatic hydrolysis with neuraminidase the sulfated sialosphingolipid was identified as 8-sulfate-sialyl-alpha-(2 leads to 6)glucopyranosyl-(1 leads to 1)ceramide. The long-chain bases were mainly phytosphingosine and its C16 homologue. The fatty acids of the sialosphingolipid were the mixture of normal and alpha-hydroxy fatty acids, their compositions were analysed by gas-liquid chromatography.