Reinvestigation of Carbohydrate Specificity of EBCA-1 Monoclonal Antibody Used for the Detection of Candida Mannan

Monoclonal antibody EBCA-1 is used in the sandwich immune assay for the detection of circulating Candida mannan in blood sera samples for the diagnosis of invasive candidiasis. To reinvestigate carbohydrate specificity of EBCA-1, a panel of biotinylated oligosaccharides structurally related to distinct fragments of Candida mannan were loaded onto a streptavidin-coated plate to form a glycoarray. Its use demonstrated that EBCA-1 recognizes the trisaccharide β-Man-(1→2)-α-Man-(1→2)-α-Man and not homo-α-(1→2)-linked pentamannoside, as was reported previously.

Characterization of Lectin from Colpomenia Sinuosa and Effect of Physico Chemical Parameters on Haemagglutination Activity

Lectin is a protein which has the ability to bind carbohydrates and named as haemagglutinin. Lectins with specific carbohydrate specificity have been purified from various plant tissues and other organisms and exploited extensively in many aspects of biochemistry and biomedicine. Similar to land plants, lectins from marine algae appear to be useful in some biological applications. Although several studies on lectins from marine algae have been reported till date, few lectins from algae have been characterized in detail. The present study was focused on the lectin isolated from C.sinuosa. The algal lectin has high sugar specificity with N-acetylglucosamine and higher enzyme activity with trypsin. This lectin was identified as CaCl2 dependent – ‘C’ type lectin and was sensitive to EDTA. Higher H.A titre value was observed with CaCl2 and the lower with MnCl2 and ZnCl2 . Significant lectin activity was observed between pH 7 to 8 and temperature between 20 to 40 O C

ConA-Like Lectins: High Similarity Proteins as Models to Study Structure/Biological Activities Relationships

Lectins are a widely studied group of proteins capable of specific and reversible binding to carbohydrates. Undoubtedly, the best characterized are those extracted from plants of the Leguminosae family. Inside this group of proteins, those from the Diocleinae subtribe have attracted attention, in particular Concanavalin A (ConA), the best-studied lectin of the group. Diocleinae lectins, also called ConA-like lectins, present a high similarity of sequence and three-dimensional structure and are known to present inflammatory, vasoactive, antibiotic, immunomodulatory and antitumor activities, among others. This high similarity of lectins inside the ConA-like group makes it possible to use them to study structure/biological activity relationships by the variability of both carbohydrate specificity and biological activities results. It is in this context the following review aims to summarize the most recent data on the biochemical and structural properties, as well as biological activities, of ConA-like lectins and the use of these lectins as models to study structure/biological activity relationships.