scholarly journals Investigations on the oligosaccharide units of an A myeloma globulin

1968 ◽  
Vol 107 (3) ◽  
pp. 341-352 ◽  
Author(s):  
G. Dawson ◽  
J. R. Clamp
Keyword(s):  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
Acid Content ◽  
Carbohydrate Content ◽  
Glycosidic Linkage ◽  
Core Oligosaccharide ◽  
Sialic Acid Content ◽  
Acetylneuraminic Acid ◽  
The Core ◽  
Polypeptide Chains

The carbohydrate content of an A myeloma globulin was investigated. The carbohydrate content was found to be unchanged when the protein was isolated from the patient over a period of 18 months. The various polymeric forms of the protein contained similar proportions of carbohydrate. The A myeloma globulin contained approx. 2 residues of 6-deoxy-l-galactose (l-fucose), 14–15 of d-mannose, 12–13 of d-galactose, 12–13 of 2-acetamido-2-deoxy-d-glucose (N-acetyl-d-glucosamine), 6 of 2-acetamido-2-deoxy-d-galactose (N-acetyl-d-galactosamine) and 5 of N-acetylneuraminic acid (sialic acid), and these were distributed between six oligosaccharide units all of which were present on the heavy polypeptide chains. The oligosaccharide units showed two kinds of heterogeneity, which have been termed central and peripheral. Central heterogeneity was shown by the presence of three completely different core units, which had the following compositions: (1) 3 residues of d-galactose and 3 of 2-acetamido-2-deoxy-d-galactose, joined to protein by an O-glycosidic linkage between acetamidohexose and serine; (2) 3 residues of d-mannose, 2 of d-galactose and 3 of 2-acetamido-2-deoxy-d-glucose, joined to protein by an N-glycosidic linkage between acetamidohexose and aspartic acid; (3) 4 residues of d-mannose and 3 of 2-acetamido-2-deoxy-d-glucose with a linkage similar to that in (2). The core oligosaccharide units showed peripheral heterogeneity in the attachment of 6-deoxy-l-galactose, 2-acetamido-2-deoxy-d-glucose and N-acetylneuraminic acid. Tentative structures are proposed for these various types of oligosaccharide unit. Glycopeptides were isolated in which the sialic acid content exceeded that of d-galactose. Explanations are given for the electrophoretic mobility and staining characteristics of the various glycopeptides.

Partial resialylation of human asialotransferrin types 1 and 2 in the rat

1984 ◽  
Vol 62 (9) ◽  
pp. 853-858 ◽  
Author(s):  
Erwin Regoeczi ◽  
Paul A. Chindemi ◽  
Maria T. Debanne
Keyword(s):  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
Acid Content ◽  
Sialic Acid Content ◽  
Small Doses ◽  
Type 3 ◽  
Time Type

125I-labeled asialotransferrin types 1 and 2 were administered in small doses to rats. The protein still in the plasma after 1–12 h was partially repurified and electrophoresed at pH 8.1, together with a transferrin standard that is composed of all six forms of the protein with respect to sialic acid content. The electrophoretic mobility of both asialotransferrins increased with time, type 2 being affected sooner than type 1. The changed mobility was due to increased electronegativity that was fully reversible by treatment of the samples with neuraminidase, thus identifying the underlying cause as partial resialylation. Asialotransferrin incubated in vitro with serum, plasma, or whole blood for 16 h exhibited no change in electrophoretic mobility. In conjunction with an earlier study on asialotransferrin type 3, it was found that the apparent speeds of resialylation of the three asialotransferrins were in the same order as their affinities for the asialoglycoprotein-binding hepatic lectin. This suggests the involvement of an endo- rather than of an ecto-transferase. Transfer of 59Fe from asialotransferrins to the liver was used to monitor the frequency of hepatocyte–asialotransferrin interactions. Iron deposition in the liver took place much more rapidly than the appearance of detectable quantities of partially resialylated asialotransferrin molecules in the circulation. It is concluded that each asialotransferrin molecule probably undergoes several passages through the hepatocyte before its glycans become modified.

Contribution of Sialic Acid to the Heterogeneity of Human Fibrinogen Polypeptide Chains

1979 ◽  
Author(s):  
C. Kuyas ◽  
A. Haeberli ◽  
P.W Straub
Keyword(s):  
Sialic Acid ◽  
Isoelectric Focusing ◽  
Acid Content ◽  
Polypeptide Chain ◽  
Sialic Acid Content ◽  
Human Fibrinogen ◽  
Single Donor ◽  
The Individual ◽  
Polypeptide Chains ◽  
Vibrio Cholerae Sialidase

Human fibrinogen, isolated from single donor or from pooled plasma, shows a heterogeneity of the Bऔ- and the γ-polypeptide chains on CM-cellulose chromatography. In order to find out whether this heterogeneity is due to the observed differences in sialic acid content of the variants (2 and 1 residue per chain; Gati et al., J.Biol.Chem.253:1315,1978) pooled or single donor fibrinogen (clottability 93-95%) was incubated 24 hrs with either vibrio cholerae sialidase or buffer. The asialofibrinogen (10% of original sialic acid) was compared with intact fibrinogen. After dithiothreitol reduction and alkylation the chains were separated on CM Sepharose. The individual homogeneous Bऔ- and γ-chains were rechromatographed on CM-cellulose. The γ-chain heterogeneity of normal fibrinogen was absent in asialofibrinogen whereas the Bऔ-chain heterogeneity appeared unaffected. Although the variants were indistinguishable on SOS-PAGE, isoelectric focusing in presence of urea demonstrated heterogeneities of both Bऔ- and γ-chains even in asialofibrinogen. Thus, the differences in sialic acid content of the main polypeptide chain variants of pooled as wel l as single donor human fibrinogen can only explain a small part of the polypeptide chain heterogeneity.

Sialoglycoproteins and sialic acids ofPlasmodium knowlesischizont-infected erythrocytes and normal rhesus monkey erythrocytes

Parasitology ◽  
1986 ◽  
Vol 92 (3) ◽  
pp. 527-543 ◽  
Author(s):  
R. J. Howard ◽  
G. Reuter ◽  
J. W. Barnwell ◽  
R. Schauer
Keyword(s):  
Sialic Acid ◽  
Rhesus Monkey ◽  
Acid Content ◽  
Sialic Acids ◽  
Galactose Oxidase ◽  
Parasite Development ◽  
Sialic Acid Content ◽  
Acetylneuraminic Acid ◽  
Total Sialic Acid ◽  
Significant Difference

SUMMARYThe effects of malaria infection on RBC sialic acids and sialoglycoproteins were studied with asexual blood-stage infections ofPlasmodium knowlesiin rhesus monkeys. Glycoprotein radio-isotope labelling methods were used to compare the sialoglycoproteins of normal RBC andP. knowlesischizont-infected RBC (SI-RBC). Tritiation of glycoproteins from SI-RBC with the standard sialidase + galactose oxidase/NaB3H4method or standard periodate/NaB3H4method was significantly decreased when compared to normal RBC. However, tritium uptake into glycoproteins was normal when SI-RBC were treated with 5-fold higher concentrations of both enzymes in the first labelling method, or with a 5-fold increase in the molar ratio of periodate to sialic acid in the second method. The mobility of tritiated host cell glycoproteins on SDS–polyacrylamide gels was identical for SI-RBC and normal RBC. New bands, possibly glycoproteins, of 230, 160, 90, 52, and 30 kDa were detected after labelling SI-RBC by the modified periodate/NaB3H4method. Sialic acid analysis of normal rhesus monkey RBC (62μg/1010RBC) revealed that 46% of the total sialic acid wasN-glycolylneuraminic acid, 33% wasN-acetyl-9-O-acetylneuraminic acid, and the remainderN-acetylneuraminic acid. SI-RBC collected either directly from infected monkeys or afterin vitroculture of ring-infected RBC in horse serum, had increased total sialic acid (126 or 115μg/1010RBC, respectively). The sialic acid content of infected RBC must increase during parasite development since RBC infected with ring-stageP. knowlesihad the same content as normal RBC. There was no significant difference in the ratio of the three sialic acids of SI-RBC and normal RBC. In contrast, the uninfected RBC from infected blood of different monkeys showed marked variation in sialic acid composition and generally had a lower sialic acid content than normal RBC.

Increase of the Sialic Acid-Rich Variants of the Bβ-and γ-Chains of Fibrinogen Zurich II

1979 ◽  
Vol 41 (04) ◽  
pp. 714-717 ◽  
Author(s):  
P W Straub ◽  
W P Gati
Keyword(s):  
Sialic Acid ◽  
Acid Content ◽  
Sialic Acid Content ◽  
Polypeptide Chains

SummaryThe abnormally high sialic acid-content of fibrinogen Zurich II could be attributed to the presence of a higher proportion of the sialic acid-rich L variant of both the γ and Bβ- polypeptide chains of fibrinogen Zurich II as compared to normal fibrinogen.

Sialic Acids in Human Gastric Aspirates: Detection of 9-O-Lactyl- and 9-O-Acetyl-N-Acetylneuraminic Acids and a Decrease in Total Sialic Acid Concentration with Age

1993 ◽  
Vol 84 (5) ◽  
pp. 573-579 ◽  
Author(s):  
A. P. Corfield ◽  
S. A. Wagner ◽  
A. Safe ◽  
R. A. Mountford ◽  
J. R. Clamp ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Thin Layer ◽  
Acid Content ◽  
Colorimetric Assay ◽  
Sialic Acids ◽  
Gas Chromatography Mass Spectrometry ◽  
Sialic Acid Content ◽  
Acetylneuraminic Acid ◽  
Total Sialic Acid ◽  
Thin Layer Chromatographic Analysis

1. The total sialic acid content of human gastric aspirates was measured using a colorimetric assay. Care was taken to optimize the assay and to eliminate interference. 2. The sialic acid content of gastric aspirates collected under resting conditions from 77 patients with non-ulcer dyspepsia was found to decrease with age from >100 μg/ml at 25 years and younger to <20 μg/ml above 70 years of age. 3. Analysis of the sialic acids by gas chromatography, mass spectrometry and thin-layer chromatography showed the presence of N-acetylneuraminic acid and two O-acylated derivatives, 9-O-acetyl- and 9-O-lactyl-N-acetylneuraminic acids. These forms were predominantly glycosidically bound. 4. Thin-layer chromatographic analysis of individual aspirate samples showed that the O-acetylated sialic acids were present in all samples, with a maximum of 25% and a minimum of 5% of the total sialic acids.

129: Sialic Acid Content of Urinary TAMM-Horsfall Protein is Reduced in Interstitial Cystitis Patients

2007 ◽  
Vol 177 (4S) ◽  
pp. 44-45
Author(s):  
C. Lowell Parsons ◽  
Mahadevan Rajasekaran ◽  
Marianne Chenoweth ◽  
Paul Stein
Keyword(s):  
Sialic Acid ◽  
Interstitial Cystitis ◽  
Acid Content ◽  
Sialic Acid Content
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