Search results for "Lactose"
showing 10 items of 115 documents
The stability and functional properties of proteoliposomes mixed with dextran derivatives bearing hydrophobic anchor groups
1992
Liposomes composed of Escherichia coli phospholipid were coated with polysaccharides bearing hydrophobic palmitoyl anchors. The effect on the stability of liposomes without or with integral membrane proteins was investigated. A high concentration of hydrophobized dextrans protected the liposomes against detergent degradation, decreased the fluidity of the membranes, prevented fusion of the liposomes and enhanced their stability. Proteoliposomes containing beef heart cytochrome-c oxidase and the lactose transport carrier of E. coli were similarly affected by coating with the dextrans. Under these conditions both membrane proteins were still active. Long-term stability of the coated liposomes…
Clinical heterogeneity in infantile galactosialidosis
1987
A new case of infantile galactosialidosis is presented. The condition was diagnosed when the patient was 4 months of age and she died at 20 months. She exhibited some of the symptoms of classical infantile galactosialidosis but no corneal clouding, cherry-red macular spot or limitation of joint mobility. Sonographic examination showed large kidneys and thickened cardiac septa, two symptoms as yet undescribed in this disorder. Urinary oligosaccharide analysis gave grossly pathological results and subsequent fibroblast enzyme analysis showed a deficiency of alpha-neuraminidase and beta-galactosidase. The patient's clinical features are compared with the few cases so far described in the liter…
Sugar specific cellular lectins of Phallusia mamillata hemocytes: Purification, characterization and evidence for cell surface localization
1989
Cellular lectins (CLs) of Phallusia mamillata were demonstrated in protein preparations obtained by salt fractionation from hemocytes sonicated in a suitable medium. Since the lectins from the precipitated fraction bind sugars containing D-galactosyl groups, they were purified by affinity chromatography on Sepharose. SDS-PAGE under reducing conditions showed that CLs are formed of two components of apparent MWs approximately 36,900 and 35,090 and thus differ from serum lectins (SLs) (MW about 62,200). The "shrinkage" observed when SLs were examined under nonreducing conditions suggest the presence of intrachain disulphide bonds which can affect the molecular structure of the SLs. CL-SL diff…
Effects of different infant formula components on calcium dialysability
1999
The in vitro methods proposed for estimating calcium bioavailability can be useful in studying the effect of dietetic factors. The aim of our work was to study the possible influence of different infant formula components – calcium, phosphorus, lactose, citric acid, ascorbic acid and proteins – on calcium bioavailability, considering dialysability to be an estimate of bioavailability. The 1981 method of Miller et al. with slight modifications (concerted action no 10 – FLAIR project) was applied to 18 commercial infant formulas of six different types: adapted, follow-up, preterm, hydrolysates, lactose-free and soy-based. Significant positive linear correlations between the amount of calcium …
PRENATAL IDENTIFICATION OF A HETEROZYGOUS STATUS IN TWO FETUSES AT RISK FOR GLUCOSE–GALACTOSE MALABSORPTION
1996
Glucose-galactose malabsorption (GGM) is an autosomal recessive disorder which presents with severe osmotic diarrhoea shortly after birth. Two proband siblings with GGM were previously demonstrated to contain a missense mutation (D28N) in the Na + -dependent glucose/galactose cotransporter (SGLTI) that accounts for the defect in sugar absorption. Prenatal screening for GGM was performed in two subsequent pregnancies in this large consanguineous family. The first exon of the SGLTI gene was PCR-amplified from genomic DNA and screened for the presence of the D28N mutation by EcoRV restriction digestion. The proband's sibling was heterozygous and a cousin was not a carrier of the D28N mutation.…
Thermal denaturation of myoglobin in water--disaccharide matrixes: relation with the glass transition of the system.
2009
Proteins embedded in glassy saccharide systems are protected against adverse environmental conditions [Crowe et al. Annu. Rev. Physiol. 1998, 60, 73-103]. To further characterize this process, we studied the relationship between the glass transition temperature of the protein-containing saccharide system (T(g)) and the temperature of thermal denaturation of the embedded protein (T(den)). To this end, we studied by differential scanning calorimetry the thermal denaturation of ferric myoglobin in water/disaccharide mixtures containing nonreducing (trehalose, sucrose) or reducing (maltose, lactose) disaccharides. All the samples studied are, at room temperature, liquid systems whose viscosity …
Adhesion of 8701-BC breast cancer cells to type V collagen and 67 kDa receptor
1992
Ductal infiltration carcinomas (d.i.c.) of the breast are potentially highly metastatic tumours, associated with drastic alterations of the architecture and molecular composition of the extracellular matrix at the tumour-host interface. 8701-BC, a recently characterized cell line, isolated from primary d.i.c., was used to study different aspects of tumor cell-substratum interactions. Since type V collagen deposition is augmented in d.i.c. we have examined the ability of 8701-BC cells to interact with this collagen species. We have found that cell binding to type V collagen was mediated by protein homologous to the 67 kDa laminin receptor (67-R). This conclusion is substantiated by the follo…
Sabella spallanzanii mucus contain a galactose-binding lectin able to agglutinate bacteria. Purification and characterization
2019
Lectins are present in almost all living organisms and are involved in several biological processes, including immune responses. In the present study, a calcium dependent galactose-binding lectin exhibiting an apparent MW of 43 kDa has been characterized and purified from the mucus of the polychaete Sabella spallanzanii by using both affinity chromatography and high-pressure liquid chromatographic methods. Its agglutinating activity towards rabbit erythrocytes was significantly modified by the addition of calcium or EDTA. The activity was optimal at temperature values comprised between 4 and 18 °C, maintain a 50% of activity between 20 and 37 °C, was significant deleted after exposure at 50…
Combinatorial solid-phase synthesis using D-galactose as a chiral five-dimension-deversity scaffold
1999
Abstract All five hydroxy groups of galactose as the scaffold are used for selective coupling of side chains in a combinatorial methodology by application of a set of orthogonally stable protecting groups in combination with a thioglycoside anchor.
A serum fucolectin isolated and characterized from sea bass Dicentrarchus labrax
2001
A lectin specific for fucose and galactose was isolated by affinity chromatography on Sepharose CL-6B from the serum of Dicentrarchus labrax. The hemagglutinating activity against rabbit erythrocytes was calcium-independent, and reached its maximum at 37 degrees C. Two protein components were found in the hemagglutinating fractions eluted from the Sepharose column. Only the 34 kDa component (DLL2) eluted from the polyacrylamide gels (SDS-PAGE) showed agglutinating activity against rabbit erythrocytes. SDS-PAGE, in non-reducing conditions, revealed a single 66 kDa protein that reacted with antibodies to the 34 kDa component. Therefore, a dimeric structure stabilized by disulfide bonds can be…