Carbohydrate Material Research Articles

The carbohydrate portions of hemocyanin from Octopus vulgaris

1. 1. Carbohydrate analyses on the hemocyanin of Octopus vulgaris showed that it contained per mg of protein: 28·8 μg of mannose, 1·7 μg of fucose and 9·0 μg of glucosamine. No sialic acid was found; the amount of acetyl groups was twice that of amino sugars. 2. 2. The experimental conditions for optimal recovery of each carbohydrate compound after acid hydrolysis have been determined. 3. 3. Extensive digestion with pronase followed by fractionation on Sephadex G-50 and G-25 led to a glycopeptide fraction containing approximately 90 per cent of the original carbohydrate material. 4. 4. Further resolution of the glycopeptide fraction was obtained by high voltage electrophoresis and seven fractions have been separated containing up to 80 per cent of sugars. Aspartic and glutamic acids, glycine, threonine, phenylalanine and serine are the most frequent among the amino acids.

Chemical composition and molecular weight distribution of dissolved organic matter produced by bacterial degradation of green algae

Chemical composition and molecular weight of dissolved organic matter were determined by employing chemical analysis and Sephadex Gel filtration method with respect to bacterial degradation products of green algae. The chemical composition is as follows; pigment materials 15%, lipid and organic acid materials 30%, proteinous materials 26% and carbohydrate materials 8%. The molecular weight of the dissolved organic matter is distributed in wide ranges. Organic matter with high molecular weight (> 50, 000) consists mainly of proteinous and carbohydrate materials, intermediate one (1, 500-50, 000) consists of pigment and lipid materials. The composition of lower molecular weight matter is not yet known. The dissolved organic matter produced by bacterial degradation of green algal cells is characterized by yellow colouring, which originates in pigments (in main chlorophyll pigments), and high molecular weight organic substances, which consist almost of proteinous substances with lesser amounts of carbohydrate substances. Although there is a considerable difference between the dissolved organic matter of bacterial degradation products and that in natural water, the former is suggested to be an important source of the latter.

Problems in the disposal of animal excreta

The traditional method of handling excreta from housed farm animals involved the provision of bedding material, normally straw, to absorb the urine and provide additional carbohydrate material for the composting process which took place during storage. Modern systems of housing generally provide for the collection and storage of the excreta in the form of slurry. This reduces labour costs and should ensure practically complete collection of both faeces and urine, thereby reducing risks of polluting water courses by drainage direct from the farmyard.

A study on the polysaccharide content of Ulva lactucal L.

A uronic acid — containing polysaccharide was isolated from the green marine algal speciesUlva lactuca by extraction with water, dilute hydrochloric acid solution, and ammonium oxalate solution. The latter agent was the best for extracting the highest amount of the polysaccharide material which contained glucuronic acid (11.4%), glucose (3.64%), arabinose (5.01%), xylose (4.55%), and rhamnose (27.33%). Partial acid hydrolysis studies and attempted fractionation on DEAE-cellulose pointed out that the polymeric carbohydrate material ofUlva lactuca may be a heteropolysaccharide. This polysaccharide appeared to contain, besides its main backbone, sequences involving glucose, arabinose and xylose.

The elaboration of protein and carbohydrate by rat parathyroid cells as revealed by electron microscope radioautography.

The parathyroid glands of young rats were radioautographed after a single injection of the protein precursor tyrosine-(3)H in the hope of identifying the sites of synthesis and migration of newly formed protein in the gland cells. The same procedure was used after injection of the glycoprotein precursor galactose-(3)H. As early as 2 min after intravenous injection of tyrosine-(3)H, the label was mainly found in the rough endoplasmic reticulum suggesting that cisternal ribosomes are sites of protein synthesis. By 5 and 10 min, much of the label had migrated from the rough endoplasmic reticulum into the Golgi apparatus. By 20 and 30 min, some label had migrated from there into secretory granules. By 45 min and 1 hr, the label content of the cell had decreased, indicating release of labeled material outside the cell. At 2 min after intravenous injection of galactose-(3)H, the label was mainly present in the Golgi apparatus, where presumably galactose is taken up into glycoprotein. By 10 min, some label appeared in secretion granules and by 30 min release of the material to the outside of the cell was under way. In conclusion, it is likely that the tyrosine-labeled protein material consists mainly of the parathyroid hormone. The galactose-labeled carbohydrate material would be either associated with the hormone in the cell or be part of a distinct glycoprotein which may be the one present on the outer surface of the plasma membrane (cell coat).

Growth and changes in pool and macromolecular components of Schizosaccharomyces pombe during the cell cycle.

ABSTRACT Amino acids, nucleotide and carbohydrate material were found to account for 46 % of the total dry weight of pool material in Schizosaccharomyces pombe growing in minimal medium. The composition of the amino acid pool was also determined by autoanalysis and was found to be unaltered during growth in 2 M sorbitol, indicating that pool amino acids are not important in the osmoregulation of the cell. Kinetic analysis of the amino acid pool using 14C-labelled amino acids showed that amino acids accumulated from the medium enter an ‘expandable’ pool distinct from the ‘internal ‘pool which is maintained during growth on minimal medium. Total RNA, protein, pool amino acid and pool ‘nucleotide’ material were estimated in synchronous cultures grown in minimal medium. All these components appeared to accumulate in an exponential manner during the cell cycle. Direct estimation of total cellular dry weight and the total pool in synchronous cultures showed that total cell dry weight increased exponentially and the pool did not fluctuate during growth in minimal medium. This contrasts with previous work on single cells of S. pombe grown in complex medium which showed that the dry weight of the pool fluctuates during the cell cycle and total cell dry weight increased linearly. Linear growth of S. pombe in malt extract broth can be accounted for by the presence of the second (‘expandable ‘) pool of amino acids formed during growth in complex medium. The phenomenon of linear growth during the cell cycle is shown to occur generally only in cells growing in complex medium. The phenomenon is considered in relation to mechanisms for controlling the size of the pool during growth in complex media.

Leakage of metabolites from mycelium of a low-temperature basidiomycete at a supramaximal temperature

Colonies of a low-temperature basidiomycete (W1) growing on agar media at 15 °C ceased growth when transferred to 30 °C. Viability was retained during at least 7 days exposure to 30 °C since growth resumed after a lag when colonies were returned to 15 °C. Measurements were made of the leakage of metabolites at 15 °C and 30 °C from mycelium of young shake cultures during a 5-h incubation period. Leakage of ninhydrin-positive material, almost negligible at 15 °C, was rapid at 30 °C. Increases in leakage of carbohydrate and ultraviolet-absorbing material occurred during the first hour at 30 °C. Subsequent leakage of carbohydrate at 30 °C, but not of ultraviolet-absorbing material, was at a slightly higher rate than at 15 °C. The possibility that these results indicate loss of cell membrane function at the supramaximal temperature is discussed.

The effect of sulfhydryl compounds on the stability of cell membranes of the lens and red cells and of the lens capsule

The proteins and the carbohydrate of the urea-insoluble albuminoid fraction of bovine lenses have been determined in three different regions of the lens, namely, the equatorial, the polar and the nuclear part. The effect of 8 m urea and 0·1 m β mercaptoethanol on these proteins and on the carbohydrate in the urea-insoluble albuminoid of the three regions was determined. It was shown that the carbohydrate consists of three different fractions, two of which are extracted by urea plus mercaptoethanol in the equatorial region. The extractability of this carbohydrate material is sharply decreased in the nuclear region and it is suggested that this is the effect of a protein that does not form part of the cell surface membrane and interferes with the extraction of the two carbohydrate constitutents from the cell surface membrane.

Comparative histochemical observations on the contributions of the acrosomal vesicle and granule to the acrosomal cap in the spermatozoa of mammals.

By applying the periodic acid-Schiff technique to frozen sections of material fixed in weak Bouin's solution and extracted with hot pyridine, the contributions of the acrosomal vesicle and granule to the acrosomal cap have been observed in the maturing spermatozoa of the American opossum, guinea pig, rabbit, marmoset and chimpanzee. In the spermatids of the opossum, the acrosomal granule is not developed and the thin, homogeneous carbohydrate layer of the acrosomal cap is derived from the concentrated material of the acrosomal vacuole. In the guinea pig, both the acrosomal vesicle and granule make the greatest contributions to the carbohydrates of the acrosomal cap; these continue to maintain their identity in the head of mature sperm. In the rabbit, marmoset and chimpanzee, the carbohydrate material of acrosomal vesicle origin is less developed and constitutes a thin layer in the lateral portions of the acrosomal cap; the carbohydrate material in its anterior portions is mainly derived from the acrosomal granule which becomes flattened; there is also a slight thickening of the intermediate layer of the acrosomal cap in this region. The distinction between the carbohydrate contributions from the acrosomal vesicle and granule disappears in the fully formed acrosomal cap which shows a homogeneously PAS-positive intermediate layer. In the chimpanzee, the acrosomal vesicle makes a relatively very small contribution to the carbohydrate layer of the acrosomal cap which is mainly formed by spreading of material from the acrosomal granule.

Immunochemical studies onTrichophyton mentagrophytes

Antigenic polysaccharide-peptide complexes were extracted from mycelia of Trichophyton mentagrophytes, and purified by gel filtration, DEAE-cellulose and proteolytic digestion. The chemical composition of crude and purified antigens is described. Purified antigens were composed chiefly of carbohydrate material, mainly glucose or mannose, with smaller amounts of galactose, glucosamine and peptides. The antigens were further evaluated by skin test in humans with naturally acquired trichophytosis, especially tinea pedis.Proteolytic digestion caused the N content of the polysaccharide-peptide complexes to fall from 1/7 to 1/8. Such peptide degradation caused a loss of the delayed reaction in skin tests. It did not, however, cause a reduction in the immediate reaction in skin tests or a disappearance of precipitin arcs in agar gels.

Some changes in biochemical composition with season and during the moulting cycle of the common shore crab, Carcinus maenas (L.)

Changes in the size and biochemical composition (glycogen, total carbohydrate, neutral fat, phospholipids, protein and non-protein nitrogen) have been followed throughout the year in the ovary and both male and female hepatopancreas of Carcinus maenas. Changes in size and biochemical composition of the hepatopancreas of Carcinus have also been examined throughout the moulting cycle. There are no clearly defined seasonal changes in either size or composition of the hepatopancreas; there is, however, a decrease in neutral fat levels in late autumn and winter in both sexes which may be due to decreased feeding at this time, and a second fall in late spring which may be caused by the recruitment to the population of previously berried and non-feeding females and recently moulted males. Carcinus appears to store less material before the moult than does Cancer and some animals appear to moult without having accumulated any appreciable reserves. In the summer, when the moulting cycle of Carcinus is characterized by ecdysis, the glycogen stores in crabs in stages C 4 and D 1 are larger than in the winter. Small, actively moulting premoult crabs when fed in captivity accumulate very large stores of glycogen in the hepatopancreas while larger, intermoult crabs in anecdysis store very little. On starvation the reserves of glycogen (and other carbohydrate material), neutral fat, and non-protein nitrogen decrease: in contrast, protein nitrogen remains constant, while phospholipid rises. On re-feeding such starved crabs on mussels the store of total carbohydrate is again rapidly established, glycogen and non-protein nitrogen fairly rapidly, and neutral fat only slowly.

The morphological alteration of particulate glycogen by en bloc staining with uranyl acetate

En bloc staining with unbuffered solutions of aqueous uranyl acetate prior to dehydration greatly altered the appearance of particulate glycogen in human skeletal muscle from cases of McArdle's disease, embryonic mouse myocardium, and chick glycogen body. Some of the effects, in particular the extraction of glycogen particles, could be duplicated by a sodium acetate-acetic acid buffer (pH 4.6). However, partial aggregation of carbohydrate material was produced only by solutions of uranyl acetate, suggesting that the heavy metal exerted effects which were independent of pH. The pattern and degree of glycogen alteration by uranyl acetate differed somewhat between the glycogen body and both skeletal and cardiac muscle. Though these differences are unexplained, the detrimental effects on the morphology of glycogen in all tissues studied indicate that en bloc staining with unbuffered aqueous uranyl acetate should not be considered an innocuous procedure. Examples are presented to indicate that acid extraction of glycogen may be a useful procedure for the differentiation of ribosomes from glycogen within muscle tissues.

The sugars of safflower

AbstractExamination of sugars in safflower hull and kernel revealed sucrose and raffinose to be predominent, with smaller amounts ofd‐glucose andd‐fructose. Galactinol (1‐O‐a‐d‐galactopyranosylmyoinositol) and other carbohydrate material which appear to contai uronic acids, fucose, glucose, fructose and arabinose, were also present.

SOME CARBOHYDRATE FRACTIONS OF A GRAY WOODED SOIL AS INFLUENCED BY CROPPING SYSTEMS AND FERTILIZERS

A study was made to determine the long-term effect of two cropping systems and various fertilizer treatments on organic carbon, nitrogen and some of the carbohydrate constituents in Breton plot soils.Organic carbon, nitrogen, hexose, pentose, uronic acid, hexosamine and hexosamine-N contents were significantly greater in soils from plots in a five-year rotation of grains and legumes than in a wheat–fallow sequence. The proportion of organic carbon in the form of hexose did not differ significantly in either of the cropping systems, but the values for pentose, uronic acid and hexosamine were markedly greater in the five-year rotation plot soils.The contents of organic carbon, nitrogen and carbohydrate materials in soils increased considerably following the manure and fertilizer applications, whereas lime had no effect. Manure and fertilizer treatments also appeared to increase markedly the proportion of organic carbon present as hexose and hexosamine.

Studies on algal substances in the sea. III. The production of extracellular organic matter by littoral marine algae

In both natural sunlight and in the dark Fucus vesiculosus L. gives no consistent or appreciable accumulation of dissolved organic matter in a closed system. On the addition of a bacteriostatic concentration of Thiomersal or the use of autoclaved sea water there was an accumulation of organic matter but the limitations of a closed system were not entirely overcome. An open system with 2 to 3 dilutions/h of fresh membrane-filtered (0.45 μ) sea water gave consistent and appreciable quantities of extracellular organic carbon which ranged from 4.4 mg C 100 g/h for Chondrus crispus Stackh. to 54.2 mg C 100 g/h for fruiting Ascophyllum nodosum (L.) Le Jol. Exudation in Fucus, which was coupled directly to photosynthesis, increased with solar radiation and was absent in the dark but unlike Fucus, Laminaria digitata (Huds.) Lamour. and Laminaria agardhii Kjellm. gave exudation in the dark. Reducing the salinity of the sea water caused an apparent reduction in the rate of exudation of organic matter by Fucus vesiculosus. Exudation also occurred in littoral algae on emersion during low tide. Desiccation caused a 68–89 % loss of moisture in surface fronds of Fucus vesiculosus and there was an organic carbon loss upon re-immersion in sea water of from 52–380 mg C 100 g . Complete clumps of algae on exposed rocks lost some 39 mg C 100 g . A light natural rainfall was more effective than artificial rain water in extraction and gave rates of exudation ranging from 7.5 and 46.4 mg C 100 g/mm of rain for Chondrus crispus and Fucus vesiculosus, respectively. Freezing at −15°C had little more effect than emersion, but algae held at −30°C for 4 h lost approximately 3 % of their organic matter upon thawing in sea water. Colorimetric assays were used to determine the nature of the exudates. Carbohydrate material appears to be most abundant followed by equal amounts of nitrogenous and polyphenolic material. Nitrogenous materials were exuded in greater concentrations during conditions which appeared injurious to the plants, including excessive desiccation, heavy rain, and extremely low temperature. A carbon balance for Fucus vesiculosus during spring conditions indicates that of the 1098 mg C 100 g fixed during the 6 h daily illuminated immersion period respiration accounts for some 276 mg C 100 g while exudation accounts for a total of 337 mg C 100 g during a 24 h period. This suggests that approximately 30 % of the total carbon or 40 % of the net carbon fixed daily is exuded by this plant. Since beds of Fucus can exceed 1000 g C/m 2 and fix at least 16.5 g C/m 2/day, extracellular organic matter production from such beds may be equivalent to 5–7 g C/m 2/day.

Studies on algal substances in the sea. II. The formation of Gelbstoff (humic material) by exudates of phaeophyta

Preliminary observations on the exudation from whole plants of the brown seaweed Fucus vesiculosus L. have confirmed the importance of this process in the ecology of inshore waters. There was an exudation of as much as 500–800 mg of phenolic and 1.0–1.5 g of carbohydrate materials per kg dry weight of alga maintained in the laboratory for 24 h. Qualitative studies on standing exudates from three of the most important Norwegian seaweeds ( Laminaria hyperborea (Gunn.) Fosl. [ cloustonii], Ascophyllum nodosum (L.) Le Jol., and Fucus vesiculosus) show that exudates form Gelbstoff material which is inseparable from that present in sea water. Observations based on paper chromatography, dialysis, Sephadex fractionation and recombination of the fractions obtained, led to the elaboration of the following hypothesis for Gelbstoff formation in algal exudates. The brown seaweeds exude a few simple precursors of (potential) phenolic nature. In the alkaline medium of sea water these form polyphenols which rapidly react with proteinaceous and carbohydrate material of either algal or other origin. The resulting phenolic complexes make up a considerable part of marine Gelbstoff. It is suggested that the larger molecular complexes of Gelbstoff are continually precipitating to form organic aggregates. The reactive phenols are toxic to some larval forms. Similar transformations of phenolic precursors to soluble Gelbstoff complexes and the subsequent formation of coloured precipitates was found to take place in bog water and in a sulphate paper mill effluent. It is therefore suggested that a common mechanism involving simple phenols, proteinaceous, and carbohydrate matter may be responsible for the formation of both terrestrial and marine humic substances (Gelbstoff).

An electrophoretic analysis of the protein components of human parotid saliva

Fresh samples of parotid saliva from one subject were analyzed by complementary anionic and cationic polyacrylamide disc gel electrophoresis systems. Nineteen protein components were evidenced with Amido Black, whereas a total of 30 discrete components were revealed by the more sensitive dye, Coomassie Brilliant Blue. The polyacrylamide gel patterns were qualitatively reproducible and have been described by grouping bands into regions designated A or A′, B or B′, C and D. Regions A and A′ contain protein and neutral carbohydrate. Regions B and B′ contain all of the α-amylase activity of parotid saliva, in the form of four or more isoenzymes. The dominant B-band also possesses acidic carbohydrate material. Region C contains five acidic components one of which contains acidic carbohydrate. Five cationic components are consistently seen in Region D.

Glycoproteins in membranes.

Summary1. Although the classical models of biomembranes have emphasized the lipid and protein nature of these structures, a small quantity of carbohydrate is present as glycoprotein and glycolipid in animal cell membranes. In this article an attempt has been made to indicate that such carbohydrate materials should be considered in any complete model of animal cell membranes.2. Various techniques that have demonstrated the presence of glycoproteins in animal cell membranes have been discussed here. In particular, cell electrophoresis, especially when the measurements are combined with specific enzyme treatments of the cells, has indicated that the net negative surface charge on intact viable cells is mainly due to sialic acid‐containing glycoproteins and not as previously thought to ionizable phosphate groups associated with a complex phospholipid system.3. Membrane‐bound antigens are complex carbohydrate‐containing macro‐molecules whose antigenic activity is principally associated with the configuration at terminal positions on the carbohydrate chains. Enzymic degradation of the glycoproteins of the intact plasma membrane of cells, especially erythrocytes, causes profound changes in the immunological behaviour of the cell.4. Histology and electron microscopy have indicated the presence of carbohydrate at the periphery of many mammalian cells. Some workers consider that such materials are present in a ‘cell coat’ covering the plasma membrane, rather than in the membrane itself.5. Studies on the isolation and characterization of membrane glycoproteins have indicated that small oligosaccharide units linked to O‐seryl or glutamyl residues in proteins are important structural units in plasma membranes.6. The glycosylation of proteins takes place within the membranes of the endo‐plasmic reticulum. Studies of glycoprotein biosynthesis suggest that the cell is able to synthesize a diversity of cell‐surface structures from a relatively small number of monosaccharides.7. Modification of the sialic acid‐containing glycoproteins of the plasma membrane affects the transport of materials in and out of cells. Glycoproteins are present in membranes other than the plasma membrane, and are therefore considered to be integral components of membranes; hence the designation ‘cell coat’, whilst useful as a descriptive term, should not be taken to indicate that glycoproteins are constituents of a functional entity separate from that of the membrane.8. Evidence that membrane glycoproteins may act as sites of interaction between cells is discussed. The involvement of glycoproteins in such a role would explain why the cell had developed a biosynthetic process capable of producing varied surface oligosaccharide structures from monosaccharides.

A kinetic model of metabolism essential to differentiation in Dictyostelium discoideum.

those of more complex organisms; (2) the lack of growth and of extensive qualitative changes at the enzyme level; and (3) the availability of the various kinds of information required to fully analyze the fine-level control of metabolism: cellular levels of substrates, products, coenzymes, and effectors; enzyme specific activities, affinity constants, etc.; and most importantly, the rates in vivo of critical reactions necessary to differentiation. The data that have now accumulated relevant to the intermediary metabolism of the cellular slime mold have reached a stage of complexity requiring a quantitative dynamic model for further analysis. The range of possible control mechanisms and their interdependence have become so complicated that it is difficult to distinguish cause from effect and random variation from significant change.' The kinetic model to be presented is preliminary and must become more complex and sophisticated as other factors known to be involved are included and as new data become available. However, even in its present simplified form, the model has provided a valuable conceptual framework for thinking in kinetic terms and for understanding some of the complexities of the differentiating cell; it has revealed new relationships and objectives not previously apparent and has made possible specific predictions, which are now being tested in the laboratory. Data Relevant to the Model.-Differentiation in the cellular slime mold can be described as a closed system in the sense that the cells are starving and independent of exogenous nutrients; dry weight decreases to about half the original value. Total carbohydrate content, based on the original dry weight, remains fairly constant throughout development.2-4 By the end of the differentiation process, it is possible to account very roughly for the total carbohydrate (anthrone-positive) material (about 14% of the final dry weight) in terms of identifiable compounds. Expressed in glucose equivalents/ml of packed cells (--100 mg dry weight) and as per cent of the original dry weight, these materials

The chemical composition of the cell walss of Penicillium digitatum Sacc. and Penicillium italicum Whem.

SUMMARY: Purified cell walls were isolated from hyphae of Penicillium digitatum Sacc. and P. italicum Whem. Electron micrographs showed microfibrils in the walls. The walls are composed chiefly of carbohydrate material, mainly D-glucose, together with D-galactose, glucosamine and mannose. Only small amounts of protein were found. Fractionation with alkali and acid indicated that the walls contain several glycans.