What are the applications of protein cross linkers?
Protein cross-linking generally refers to the process of chemically joining two or more molecules or polymer chains in an effort to check and investigate protein-protein interactions. Cross-linking agents or "cross-linkers" as they are fondly called by most researchers, have the ability to covalently bind with two or more molecules or functional groups since they contain at least two reactive ends that can attach themselves to several functional groups such as primary amines, carboxyls, sulfhydryls, carbohydrates and carboxylic acids.
Cross-Linking Applications
Due to their unique nature, cross-linking agents can be used in the following applications:
Structural and functional studies
Protein and receptor interactions
Preparation of immunogens and immunotoxins
Cell membrane and cell surface studies
Solid-phase immobilization
Protein-protein conjugation
Protein to DNA/RNA cross-linking
Reactive group transfer
Structural and functional studies
Cross-linking agents can be used to investigate the structure, subunit composition and various folding patterns of a particular protein and stabilize the conformational changes that proteins undergo. You can also experiment with different lengths of identical cross-linkers to quantify the molecular distance between functional groups within the protein structure. Just keep in mind that cross-linkers with short to medium spacer arms are suitable for intramolecular cross-linking while those with longer spacer arms are best for intermolecular cross-linking.
Protein and receptor interactions
Protein cross-linkers can also help you establish the association between proteins and the interactions that exist between ligands and receptors. You can use a panel of similar cross-linkers with varying spacer arm lengths to achieve this purpose, especially if you know the distance between two potential molecules. Heterobifunctional cross-linkers with one non-specific and photo-activatable end can be particularly useful for protein interaction analysis.
Preparation of immunogens and immunotoxins
Cross-linking agents can also be used in the production of antibodies and immunotoxins. Sulfhydryl-amine reactive heterobifunctional cross-linkers and carbodiimides are ideally used in the preparation of antibodies while cleavable disulfide-containing cross-linkers are found to be more suitable in the preparation of immunotoxins.
We will take a look at some of the other important applications of protein cross-linking in our next post so please watch out for it!