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1.
1. Milk samples were obtained at various stages of lactation from 16 captive eastern quolls. 2. The mean milk carbohydrate concentration was 7.4% (w/v; total hexose) at 8 weeks post partum, decreasing to 5.2% at 17 weeks and to less than 2% at the end of lactation. 3. The predominant monosaccharide constituent of the carbohydrates was galactose, followed by glucosamine, glucose and sialic acid. 4. Thin layer and gel chromatography showed that the milk carbohydrates consisted of lactose and a variety of higher oligosaccharides, some of which appeared to be identical to oligosaccharides of known structure previously isolated from milk of the tammar wallaby, Macropus eugenii. 5. In general, both the quantitative and qualitative changes observed in the milk carbohydrates of the eastern quoll were similar to those documented for macropodids.  相似文献   

2.
Protein-polysaccharides of pig laryngeal cartilage   总被引:23,自引:18,他引:5  
1. Protein-polysaccharides of chondroitin 4-sulphate were extracted with neutral calcium chloride from pig laryngeal cartilage that was not completely homogenized. The protein-polysaccharides were purified by precipitation with 9-aminoacridine. On zone electrophoresis in compressed glass fibre at pH7.2 it was separated into two fractions, although two distinct zones were not obtained. These fractions, which had already been shown to differ in their antigenic determinants, also differed considerably in amino acid composition, total protein, hexose and glucosamine contents. 2. The fraction of higher mobility contained approx. 2% of protein and only traces of glucosamine. Serine and glycine accounted for over half the total amino acid residues, but aromatic, basic and sulphur-containing amino acids were not detected. The weight-average molecular weight, determined by sedimentation, was 230000. 3. Assuming that there was the same sequence of neutral sugars at the linkage points as in PP-L fraction (protein-polysaccharide light fraction), the approximate molar ratio of hexose to serine suggested that most of the serine residues were linked to chondroitin sulphate chains. Support for this was derived from the agreement between the weight-average molecular weight of the chondroitin sulphate-peptide after proteolysis, and the chain weight calculated from its serine content. The chain weight based on the serine content of the fraction of higher electrophoretic mobility was approximately similar. 4. In contrast, the fraction of lower electrophoretic mobility resembled PP-L fraction in its amino acid composition, protein and glucosamine contents. The presence of glucosamine, together with the higher hexose content, suggested that this fraction contained some keratan sulphate. 5. The relatively low molecular weight of the fraction of higher mobility enabled it to be extracted without complete disintegration of the cartilage. The unlikelihood of its being produced by autolytic enzymes is discussed.  相似文献   

3.
1. Eight gangliosides were purified from chloroform/methanol extracts of human kidneys by using modified Folch partition, dialysis, ethanol precipitation, silicic acid column chromatography and preparative thin-layer chromatography. 2. By thin-layer chromatographic behaviour and gas-liquid chromatographic determinations the main gangliosides in human kidney are N-acetylneuraminyllactosylceramide (74% of total) and di-N-acetylneuraminyllactosylceramide (19% of total). 3. Five hexosamine-containing fractions were isolated. Four of them were homogeneous on thin-layer chromatography, and one contained two gangliosides. By gas-liquid chromatography-mass spectrometry it was shown that two gangliosides (together 5% of total) contain glucosamine, and one (1% of total) contains galactosamine. The other of the glucosamine gangliosides contains fucose in addition to the usual sugars found in gangliosides. Of the two remaining hexosamine positive fractions (together 1% of total) one was homogeneous on thin-layer chromatography, the other contained two gangliosides. These two fractions contained both glucosamine and galactosamine. 4. The main long-chain base in all fractions was sphingosine.  相似文献   

4.
Milk was collected at various stages of lactation from a group of tammar wallabies, M. eugenii, in which parturition had been synchronized. The milk carbohydrate was determined by a phenol-sulfuric acid method which had been modified to give equal colour yields for galactose and glucose. The mean carbohydrate content increased gradually during the first 6 months of lactation to a peak of 13 g hexose/100 ml of milk, but then fell rapidly to much lower values, over the following 2 months. Throughouth lactation, galactose was the predominant monosaccharide constituent of acid hydrolysates of the milk carbohydrate. Glucose, glucosamine, galactosamine and sialic acid were the only other monosaccharides present. Qualitative changes were investigated by gel filtration and thin-layer chromatography. During the first 6 months post partum the milk carbohydrate was composed of a variety of oligosaccharides including lactose, but from 8 months onwards it consisted mainly of free monosaccharides. Between 6 and 8 months an intermediate pattern was observed, i.e. a mixture of lower oligosaccharides and free monosaccharides. In two animals which suckled both a new-born pouch young and a young at foot, the mammary gland supplying the new-born secreted milk which was rich in oligosaccharides, whereas that supplying the young at foot produced milk in which the carbohydrates were mainly free monosaccharides, and which had a much lower carbohydrate content.  相似文献   

5.
Detection of enteric viruses in treated drinking water   总被引:1,自引:0,他引:1  
The occurrence of viruses in conventionally treated drinking water derived from a heavily polluted source was evaluated by collecting and analyzing 38 large-volume (65- to 756-liter) samples of water from a 9 m3/s (205 X 10(6) gallons [776 X 10(6) liters] per day) water treatment plant. Samples of raw, clarified, filtered, and chlorinated finished water were concentrated by using the filter adsorption-elution technique. Of 23 samples of finished water, 19 (83%) contained viruses. None of the nine finished water samples collected during the dry season contained detectable total coliform bacteria. Seven of nine finished water samples collected during the dry season met turbidity, total coliform bacteria, and total residual chlorine standards. Of these, four contained virus. During the dry season the percent removals were 25 to 93% for enteric viruses, 89 to 100% for bacteria, and 81% for turbidity. During the rainy season the percent removals were 0 to 43% for enteric viruses, 80 to 96% for bacteria, and 63% for turbidity. None of the 14 finished water samples collected during the rainy season met turbidity standards, and all contained rotaviruses or enteroviruses.  相似文献   

6.
Detection of enteric viruses in treated drinking water.   总被引:8,自引:3,他引:5       下载免费PDF全文
The occurrence of viruses in conventionally treated drinking water derived from a heavily polluted source was evaluated by collecting and analyzing 38 large-volume (65- to 756-liter) samples of water from a 9 m3/s (205 X 10(6) gallons [776 X 10(6) liters] per day) water treatment plant. Samples of raw, clarified, filtered, and chlorinated finished water were concentrated by using the filter adsorption-elution technique. Of 23 samples of finished water, 19 (83%) contained viruses. None of the nine finished water samples collected during the dry season contained detectable total coliform bacteria. Seven of nine finished water samples collected during the dry season met turbidity, total coliform bacteria, and total residual chlorine standards. Of these, four contained virus. During the dry season the percent removals were 25 to 93% for enteric viruses, 89 to 100% for bacteria, and 81% for turbidity. During the rainy season the percent removals were 0 to 43% for enteric viruses, 80 to 96% for bacteria, and 63% for turbidity. None of the 14 finished water samples collected during the rainy season met turbidity standards, and all contained rotaviruses or enteroviruses.  相似文献   

7.
In the present study, efforts were made towards identifying carbohydrates and glycoproteins involved in bovine in vitro fertilization (IVF). In vitro matured cumulus-oocyte complexes (COCs) were inseminated in the presence of a variety of carbohydrates and glycoproteins to determine which glycoconjugates act as competitive inhibitors of oocyte penetration. Among the carbohydrates and glycoproteins tested, D-mannose, fucoidan, dextran sulfate, and fibronectin were the most potent inhibitors of oocyte penetration (90% or more inhibition), while L-fucose and vitronectin inhibited the penetration rate to a lesser extent (around 50% inhibition). Other carbohydrates caused less than 40% inhibition (i.e., D-galactose, N-acetyl-D-galactosamine, D-fucose, and sialic acid) or were not effective as inhibitors of oocyte penetration (i.e., mannan, N-acetyl-D-glucosamine, dextran, and heparan sulfate). Heparin was the only carbohydrate that significantly increased the penetration rate. To exclude a possible toxic effect on spermatozoa, sperm motility was evaluated over time by means of computer-assisted sperm analysis in the presence of carbohydrates and/or glycoproteins that inhibited the penetration rate with 40% or more. L-fucose, dextran sulfate, and vitronectin did not significantly influence total and progressive sperm motility, whereas D-mannose, fucoidan, and fibronectin caused a significant, but slight reduction in both motility parameters. These results are indicative for the involvement of D-mannose, L-fucose, fucoidan, dextran sulfate, fibronectin, and vitronectin in bovine IVF.  相似文献   

8.
Inositol glycans were prepared from reductively radiomethylated human erythrocyte acetylcholinesterase by sequential treatment with Proteinase K, methanolic KOH, and phosphatidylinositol-specific phospholipase C. Four glycans denoted alpha-delta were resolved by anion exchange high performance liquid chromatography (HPLC). Each glycan was subjected to hydrolysis in 4 M trifluoroacetic acid, and their hexose and hexose phosphate compositions were determined by anion exchange HPLC. The predominant glycan alpha showed a relative stoichiometry of 2 mannoses, 1 mannose 6-phosphate, 1 radiomethylated glucosamine, 1 radiomethylated ethanolamine, and 1 inositol. In contrast, the stoichiometry of glycan beta was 1 mannose, 2 mannose 6-phosphates, 1 radiomethylated glucosamine, 2 radiomethylated ethanolamines, and 1 inositol. Glycans alpha and beta were analyzed by electrospray ionization-mass spectrometry, and respective parent ions of m/z 1266 and 1417 were observed. The fragmentation pattern produced by collision-induced dissociation mass spectrometry of these parent ions was consistent with a common linear core glycan sequence prior to radiomethylation of ethanolamine-phosphate-mannose - mannose - mannose - glucosamine - inositol. Glycan alpha contained a single additional radiomethylated phosphoethanolamine branching from the mannose adjacent to glucosamine, whereas glycan beta contained two additional radiomethylated phosphoethanolamines, one branching from each of the mannoses nearest to glucosamine. Trifluoroacetic acid hydrolysis did not cleave within the N,N-dimethylglucosamine-inositol-phosphate moiety in these glycans, and this component was resolved by anion exchange HPLC and structurally confirmed by mass spectrometry. Dephosphorylation of this component by treatment with 50% HF produced N,N-dimethylglucosamine-inositol, and this conjugate was shown to have a characteristic elution time on cation exchange chromatography in an amino acid analyzer. Both of these fragments involving an intact radiomethylated glucosamine-inositol bond are proposed as new diagnostic indicators in the search for minor glycoinositol phospholipids in cells and tissues.  相似文献   

9.
The heterogeneity and chemical composition were investigated in κ-casein from colostrum. The acid casein was obtained from four different Holstein cow colostra. The yield of acid casein from colostrum was higher than that from normal milk. κ-Casein from colostrum was prepared by the gel filtration method of Yaguchi et al. The gel filtration profiles differed among the four colostrum acid caseins.

Colostrum κ-casein was fractionated on a DEAE-cellulose column into one nonadsorbed and six adsorbed fractions with increasing salt concentration. Six adsorbed fractions had the same molecular weight and stabilizing ability for αs1-casein in the presence of calcium ion. The amino acid composition and the phosphorus content of the adsorbed fractions were identical, but fractions eluted with high salt concentrations had more carbohydrates (galactose, sialic acid, glucosamine, galactosamine). Colostrum κ-casein was characterized by a higher content of carbohydrate moiety in comparison with normal κ-casein. Also glucosamine which has not been found in normal κ-casein was detected in colostrum κ-casein. The κ-casein component from colostrum contained at least one molecule of carbohydrate, though the carbo hydrate-free component was detected in normal κ-casein.  相似文献   

10.
The carbohydrate composition of arterial basement-membrane-like material was investigated. Basement-membrane-like material was isolated from cultures of aortic myomedial cells by a sonication/differential-centrifugation technique. Purified basement-membrane-like material contained a total of 5% sugars, comprising glucose, galactose, mannose, fucose, sialic acid, glucosamine and galactosamine in the approximate molar proportions 3.2:3.5:3.4:3.2:1:5.5:3.1. In addition, small amounts of xylose were found. Analyses for uronic acid showed that glycosaminoglycans comprised about 1% of isolated basement-membrane-like material. The carbohydrate composition indicated the presence of complex-type oligosaccharides in addition to hydroxylysine-linked disaccharides. [3H]Glucosamine-labelled glycopeptides obtained by proteinase digestion and gel filtration were resistant to endo-beta-N-acetylglucosaminidase D, but more than 10% were susceptible to alpha-mannosidase, demonstrating the presence of high-mannose-type oligosaccharides. The distribution of carbohydrates among peptides of basement-membrane-like material on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was investigated after labelling with [3H]mannose, [3H]fucose, [3H]galactose and [3H]glucosamine. Among peptides that appeared to carry carbohydrates were a proteoglycan(s) and seven glycoproteins in the molecular-weight range 120 000-700 000.  相似文献   

11.
Cerebrosides have been isolated from adult human aortic tissue. Each aorta was divided into portions classified as normal, fatty streaks, fibrous plaques, or complicated lesions. The cerebrosides were isolated by Florisil column chromatography, mild alkaline methanolysis, a second Florisil column, and preparative thin-layer chromatography. The concentration of cerebrosides was higher in fatty streaks than in the more advanced plaques; apparently normal tissue gave the same cerebroside content as plaques found in the same aorta. The quantities of cerebrosides ranged from 0.01 to 0.73% of the total lipid. Of the 16 cerebroside samples isolated, 10 contained glucosyl ceramide, 1 contained galactosyl ceramide, and 5 were not analyzed for specific hexose. The fatty acid distribution was determined for 11 of the samples; it was similar to that of spleen cerebrosides. We suggest that aortic cerebrosides originate in the plasma. "Normal tissue" cerebrosides contained less unsaturated fatty acid than cerebrosides from a diseased area of the same aorta. Preparative thin-layer chromatography, the last step of cerebroside isolation, always separated at least two unidentified substances. One of these substances yielded both glucose and galactose on acid hydrolysis. Their removal from the cerebrosides accounts for the lower values for cerebroside compared to other authors' determinations.  相似文献   

12.
Derepression of hexose transport in a line of Syrian hamster fibroblasts (Nil) and polyoma-transformed (PyNil) hamster fibroblasts is obtained when cells are either starved for glucose or fed with fructose as the only hexose source. D-glucosamine feeding of these cells does not alter the repressed state with regard to hexose transport. High, derepressed rates of galactose transport were changed to low, repressed rates, within 18 hours of refeeding glucose-starved cells with D-glucosamine as the only hexose source. Nil and PyNil cells, when cultured in the presence of D-glucosamine, undergo rapid reductions in total cellular uridine 5′-triphosphate (UTP) pool sizes. By contrast, the total cellular pools of adenosine 5′-triphosphate, guanosine 5′-triphosphate, and cytosine 5′-triphosphate (ATP, GTP, and CTP) were only moderately affected by the treatment of the cells with glucosamine. The metabolic drain of the UTP pools in PyNil cells was much more pronounced than in the untransformed cells. The larger and more rapid metabolic lability of UTP pools in the transformed cells may be the primary reason for the selective toxicity of glucosamine on tumor cells. A comparison of the effects of glucosamine on hexose-starved Nil and PyNil cells demonstrated that only the untransformed cells were able to utilize glucosamine to increase the hexose starvation-depleted pools of all nucleoside triphosphates. Accumulation of UDP-glucosamine and UDP-N-acetylglucosamine followed the reduction in the UTP pools. Inhibition of protein synthesis by cycloheximide during glucosamine feeding led to higher levels of UDP-glucosamine and UDP-N-acetylglucosamine accumulation. It is suggested that the drain of UTP pools during glucosamine treatment proceeds through the formation of the UDP-aminosugars which turn over due to the action of intracellular UDP-aminosugar pyrophosphatase activities.  相似文献   

13.
Methods for the automated analysis of hexose, uronic acid, and protein using the Technicon AutoAnalyzer II have been developed by modifying previously published procedures. A method of separating glucosamine and galactosamine, which is eminently suited to quantitating one in the presence of a large amount of the other, is reported. Procedures that can be recommended for determining the amino acid content and individual neutral sugars of proteoglycans or glycosaminoglycans are also described.  相似文献   

14.
The examination of substances formed during induced autolysis by Aspergillus niger was continued in this work, which dealt in particular with carbohydrates. The autolysate contained a large amount of d-glucose (14 to 20% dry wt) and traces of glycolic aldehyde, dihydroxyacetone, ribose, xylose, and fructose. It also contained glycopeptides (about 10% dry wt), which were split from the cell wall during autolysis and which differed from one another in their level of polymerization and their composition. They were constituted by glucose and mannose, glucose and galactose, or mannose, glucose, and galactose (mannose being the most abundant in this case), and amino acids (chiefly alanine, serine, glutamic acid, and aspartic acid). During autolysis, only a part of the cell wall was dissolved, since it retained its shape. Upon further chemical hydrolysis, it produced mostly glucose and glucosamine, and smaller amounts of mannose, galactose, and amino acids. Presumably, glucomannoproteins and glucogalactoproteins were present in the intact cell as a macromolecular complex, constituting, together with chitin, the major part of the cell wall of Aspergillus.  相似文献   

15.
1. Eggs of the potato cyst-nematode (Heterodera rostochiensis Woll.) were isolated by sieving a suspension of crushed cysts. Eggs were broken open by ultrasonic vibration and the egg shells separated from the released larvae by centrifuging in a potassium tartrate density gradient. About 1 mg. of dried egg shells was obtained from 1000 cysts. 2. The major constituent of the egg shells was protein (59%, calculated from nitrogen content). About 80% of the egg shells went into solution on acid hydrolysis. Of the 18 amino acids determined with the Technicon Auto-Analyser, proline was most abundant and, with aspartic acid, glycine and serine, made up about 64% by weight of the total amino acids. The small amounts of aromatic and sulphur-containing amino acids, and the presence of hydroxy-proline, indicate a collagen-like protein. 3. The egg shells gave a positive van Wisselingh colour test for chitin, and glucosamine was detected in their acid hydrolysate by chromatography. The glucosamine content of the egg shells, determined by the Elson-Morgan colorimetric method, was 7%, corresponding to about 9% chitin. 4. Dried egg shells contained about 7% of lipid, 6% of carbohydrate and 3% of ash. Polyphenols (3% by weight of the egg shells) were detected in the acid hydrolysates. 5. Neither the collagen nor the chitin showed evidence of crystallinity when examined by X-ray diffraction.  相似文献   

16.
A lectin was isolated from the venom of scorpion Buthus occitanus sp. by means of Sephadex G-50 gel filtration and CM-cellulose ion exchange chromatography. The homogeneous lectin preparation consisted of homodimeric molecules with a subunit Mr of 9.3 kDa. Glycine, alanine, and serine dominated in the lectin amino acid composition. The lectin was a glycoprotein containing 20% carbohydrates (predominantly mannose and glucose). Trypsin-treated murine erythrocytes agglutinated at the lectin concentration of 32 micrograms/ml. Hemagglutination was inhibited by carbohydrates (L-fucose > D-glucose > L-rhamnose > D-xylose). The lectin revealed no phospholipase or hyaluronidase, nor toxic activity.  相似文献   

17.
An intramolecular turnover of the terminal carbohydrates L-fucose, N-acetylneuraminic acid and D-galactose is a characteristic property of several liver plasma membrane glycoproteins, first demonstrated for dipeptidylaminopeptidase IV (EC 3.4.14.5., DPP IV). The core carbohydrates D-mannose and N-acetyl-D-glucosamine turn over like the polypeptide chain. The ratio of apparent half-lives of L-fucose and L-methionine of DPP IV is shifted from 0.17 in normal liver to 0.60 in regenerating liver. The ratio of half-lives of N-acetylneuraminic acid and L-methionine is only slightly changed from 0.43 in normal liver to 0.61 in regenerating liver. The ratio of apparent half-lives of D-mannose and L-methionine amounts to 0.80 in normal liver and 0.71 after partial hepatectomy. From this a drastic reduction of the intramolecular turnover of L-fucose on plasma membrane DPP IV in regenerating liver can be derived. The intramolecular N-acetylneuraminic acid turnover is affected to only a minor extent. D-Mannose turns over like the polypeptide in both normal and regenerating liver. The intramolecular L-fucose turnover may be involved in membrane glycoprotein recycling, which presumably is altered in regenerating liver. Additionally, L-fucose could regulate the rate of degradation of DPP IV, since core-fucosylated glycoproteins appear to be resistant to mammalian endo-N-acetylglucosaminidase.  相似文献   

18.
The carbohydrate composition of dextranase from Penicillium funiculosum 15, as well as the composition of products of dextran deep hydrolysis by the enzyme were studied. The products are normally used to stabilize the enzyme during its purification. Using the methods available, it was possible to identify only part of strongly bound (adsorbed) carbohydrates. It was found that dextranase from Pen. funiculosum 15 contained two types of carbohydrates strongly bound with protein: adsorbed and covalently bound carbohydrates. A procedure allowing a complete separation of adsorbed carbohydrates was developed. The procedure is based on the use of stabilizing additives of readily separable carbohydrates. The enzyme, which is shown by polyacrylamide gel electrophoresis in the presence of Na-dodecyl sulfate and beta-mercaptoethanol to be homogeneous, consists of 313 amino acid residues, 3 glucosamine residues and residues of mannose, galactose and fucose in the ratio 6:2:1.  相似文献   

19.
Glycoproteins and proteins were extracted from segments or scrapings of the intestine in tube-fed, vitamin-A-deficient and control rats on the eight day after withdrawal of retinoic acid from the diet by using either 1% sodium dodecyl sulfate (SDS) or aqueous 5 mM EDTA (pH 7.4). They were then fractionated on columns of Sepharose 4B. Water-soluble peak I material contained large (Mr > 106; S20 = 11.7) glycoprotein aggregates which were rich in hexose, fucose and sialic acid. These aggregates dissociated into several non-identical glycoprotein and protein subunits upon treatment with dithiothreitol. The protein matrix was rich in threonine, valine, proline, serine, glutamate and aspartate. Peak II consisted of smaller proteins and glycoproteins, the latter with much lower carbohydrate content. Some peak II glycoproteins also dissociated into subunits in the presence of dithiothreitol. Peak III consisted mainly of a heterogenous assortment of proteins, including some glycoproteins of low carbohydrate content. Antibodies either to peak II or to peak III reacted both with peaks II and III but not with peak I.The total weight, carbohydrate composition of glycoproteins and the ratio of carbohydrate to protein in the total extract or in each of the three fractions were not significantly affected in vitamin A deficiency despite decreased incorporation of all labeled precursors. Rather, the relatively lower incorporation (approx. 0.8) of radioactive sulfate, D-glucosamine and L-fucose into total SDS-soluble duodenal glycoproteins of vitamin-A-deficient rats could be explained on the basis of a reduced prevalence of goblet cells alone. In contrast, the relative incorporation rate of L-fucose into peak I, but not into peaks II and III, ranged from 0.25 to 0.45, less than expected on the basis of fewer goblet cells alone. The incorporation of radioactive threonine into all protein fractions was reduced to 60% of normal in vitamin A deficiency. Thus, the well established observation that intestinal tissue of vitamin-A-deficient rats synthesizes high molecular weight glycoproteins poorly might be due to several interacting factors: (1) a reduced prevalence of goblet cells, (2) a lower rate of protein synthesis, (3) a lack of retinyl phosphate for the formation of mannosyl or other carbohydrate derivatives, and (4) secondary, and as yet undefined, cellular changes which preferentially reduce the rate of synthesis of high molecular weight fucose- and sialic-acid-enriched glycoproteins.  相似文献   

20.
The lipopolysaccharide (LPS) ofVeillonella parvula ATN, a human oral isolate, was characterized. Lipid A accounted for, approximately 55% of the weight of the LPS complex. Major fatty acids included tridecanoic acid, 3-hydroxytridecanoic acid, and 3-hydroxypentadecanoic acid. Glucose was the only hexose detected. Amino compounds included glucosamine, galactosamine, and glycine. Heptose and 2-keto-3-deoxyoctonic acid (KDO) were also present. Alterations in the culture medium formulation affected LPS extraction yields. Furthermore, evidence was presented for the existence of a heterogeneous LPS component, with changes in growth conditions giving rise to more or less hydrophilic types of LPS.  相似文献   

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