0000000000214923
AUTHOR
Gerd Uhlenbruck
showing 6 related works from this author
Characterization of the trimeric, self-recognizing Geodia cydonium lectin I.
1983
A D-galactose-specific lectin I was extracted from the sponge Geodia cydonium and purified by affinity chromatography. The molecular weight of lectin I as determined by high-pressure liquid gel chromatography, was found to be 36500 +/- 1300. Disc gel electrophoresis in the presence and in the absence of sodium dodecyl sulfate showed that lectin I is a trimer composed of three different subunits (Mr: 13800, 13000 and 12200); two of the three subunits are linked by one disulfide bond. Isoelectric focusing gave a pI of 5.6 for the native molecule and a pI of 4.4 and of 7.4 for the subunits. The three subunits carry carbohydrate side chains, composed of D-galactose (94%) and of arabinose (5%). …
Aggregation of sponge cells. Isolation and characterization of an inhibitor of aggregation receptor from the cell surface.
1979
From the cell membranes of the sponge Geodia cydonium a component was isolated and purified which inhibits the aggregation factor isolated from the same source; the component was termed anti-aggregation receptor. This molecule was characterized as a glycoprotein (54% neutral carbohydrate) and its molecular weight is in the range of 180,000 One biological site of the anti-aggregation receptor was determined to be D-galactose. Indirect evidence presented seems to indicate that this molecule is present in an active form in aggregation-deficient cells and absent in aggregation-susceptible cells.
On the role of D-glucuronic acid in the aggregation of cells from the marine sponge Geodia cydonium.
1979
Abstract The aggregation receptor (AR) from the marine sponge GEODIA CYDONIUM was analyzed with respect to its monosaccharide composition. Three major sugars ( D -galactose, D -glucose and D -glucuronic acid) accounted for about 85 % of the total carbohydrate. Negative results with different lectins directed against D -galactosyl, N -acetyl- D -galactosaminyl and N -acetyl- D -glucosaminyl groups, respectively, showed that these sugars are serologically unreactive in AR. Positive serological reactions were obtained with CONCANAVALIN A and LIMULUS POLYPHEMUS agglutinin. AR also reacted strongly with the basic polymer poly- L -lysine. Reaggregation experiments performed on the basis of these …
Polyclonal antibodies to mannan from yeast also recognize the carbohydrate structure of gp120 of the AIDS virus: an approach to raise neutralizing an…
1990
This study initiates a new method of developing an antigen which might be useful in the prevention of HIV-1 infection. Using a mannan preparation from Saccharomyces cerevisiae neutralizing antiserum was raised in rabbits which prevents HIV-1 infection in vitro up to a titre of 1:128. The corresponding antibody preparation neutralized the in vitro infectivity down to a concentration of 5 micrograms/ml. Analytical studies suggest that the antibodies are directed against the mannose residues of the HIV-1 glycoprotein (gp) 120 and its precursor gp 160.
Sponge aggregation factor and sponge hemagglutinin: possible relationships between two different molecules.
1979
Abstract A lectin from the marine sponge GEODIA CYDONIUM was isolated and characterized. GEODIA lectin (GL) agglutinates human red blood cells irrespective of the ABO blood group and precipitates with a variety of D -galactose containing glycosubstances, i.e. certain snail galactans, bovine erythrocyte glycoprotein and PNEUMOCOCCUS type XIV polysaccharide. The only simple sugars inhibiting the GL-mediated hemagglutination were lactose and n -acetyl- D -galactosamine. GL was purified by affinity chromatography on Sepharose 4B almost to homogeneity as tested by polyacrylamide disc gel electrophoresis. Positive staining of the lectin band with Coomassie brilliant blue and PAS suggest that GL i…
Xenograft rejection in marine sponges. Isolation and purification of an inhibitory aggregation factor from Geodia cydonium.
1981
In sponges there exists a graft rejection mechanism in which an inhibitory aggregation factor is involved. The inhibitory aggregation factor has been isolated from a culture medium containing dissociated cells of the sponge Geodia cydonium. Using ion-exchange and gel fractionation the factor was purified and shown to be electrophoretically pure. The factor has a molecular weight of 27000 and was characterized as a glycoprotein. The activity of the inhibitory aggregation factor was not affected by heat treatment, but treatment with trichloroacetic acid resulted in the irreversible loss of activity. The inhibitory aggregation factor affects the aggregation-factor-mediated reaggregation of dis…