Isolation and Characterization of Concanavalin A

Abstract

Plant lectins are specific carbohydrate- binding proteins that are widely distributed in plant species. Among which there are legume protein called Concanavalin A. It participates in many physiological processes & are capable of modulating the immune response. It has remarkable anticancer properties and is associated with call proliferation, cell adhesion & induction of apoptosis. Lectins also have their application in non-technology & development of glycoproteomics, which is a powerful tool in characterization of lectin and will be indispensable for development of lectin based drug in near rear future. In this thesis report, we have outline all up-to-date advances in Concanavalin A and their application in cancer treatment is also described. Also we have performed Extraction and characterization of Concanavalin A. Concanavalin A is industrially important lectin used to prepare affinity matrix by covalently attaching it to a suitable matrix support for purification of other carbohydrate binding lectins as well as other glycoproteins with exposed glucose/mannose residues. Since concanavalin A has sites with affinity for glucose/mannose, other lectins that have binding sites for glucose/mannose can be purified employing a single step affinity chromatography. However, since concanavalin A has high tendency to form aggregates in alkaline pH, the affinity matrix with bound concanavalin A becomes unstable in alkaline pH that renders the column ineffective. Owing to this limitation of using the concanavalin A based affinity column in alkaline pH range, there is huge scope for improving the efficiency of such affinity column in alkaline pH range. For this, it is important that the tendency of concanavalin A to form aggregates in alkaline pH is reduced or delayed. In order to attain this objective, one strategy is to develop mutant concanavalin A with reduced tendency to form pH induced aggregates. However, it is important that residues critical in seeding of aggregates are identified so that suitable mutants may be developed by knocking off critical residues. Another approach is the use of cosolvents that may stabilise concanavalin A in alkaline pH range. So, In this report, we have compiled the results obtained in preliminary studies to identify the sticky residues/regions critical in formation of pH induced aggregates.