Thermo Scientific EZ-Link Amine-PEG4-desthiobiotin is a pegylated amine compound that is biotin-like The group is elutable from streptavidin and is therefore suitable for carbodiimide (EDC) coupling with carboxylates for labeling and purification.

EZ-Link Amine-PEG4-Desthiobiotin No-Weigh Specifications Features:

•Desthiobiotin—Biotin analogs can be easily obtained from Elutes in streptavidin, an ideal feature for affinity purification applications
•Amine Activation—EDC and other cross-linkers can be used to interact with primary amines on protein and material surfaces. Link
•PEGylation—The polyethylene glycol (PEG) group in the spacer arm enhances the water solubility of the biotinylated molecule

The desthiobiotin compound is Amine-modified analogue of biotin, containing 4 units Polyethylene glycol (PEG) spacer arm. Use carbodiimide cross-linking agent EDC (product number 22980) to combine primary amines with surface materials and peptides Dethiobiotinylation is achieved by coupling the carboxyl group on the class or protein. EDC activates the carboxyl group and binds to the –NH2 group of amino-biotin, forming an amide bond. Desthiobiotin tags bind streptavidin and other biotin-binding proteins with high specificity but tend to elute under mild conditions (i.e., in a manner that is competitively displaced by conventional free biotin). Therefore, this reagent is amine-PEG3-biotin for avidin-biotin technology ( 21347) where nondenaturing elution of tagged proteins is required. No-Weigh format (5 x 1 mg resealable vials) eliminates the difficulty of weighing small amounts of reagents and protects unused reagents from degradation as much as possible.

Desthiobiotin and biotin
Desthiobiotin is a monocyclic, sulfur-free biotin analogue. The binding specificity of streptavidin is almost the same as that of biotin, but the affinity is lower than that of biotin (1/Kd = 10^11 vs. 10^15M, respectively) [1-2]. Therefore, desthiobiotinylated bait proteins and their interacting partners can be easily and specifically washed from streptomycin affinity resins using mild conditions based on competitive displacement with free biotin. Come out. For sedimentation assays using biological samples, this soft release characteristic of desthiobiotin also helps to minimize co-purification of endogenous biotinylated molecules when elution of target protein complexes with free biotin Still bound to strepavidin. The modified avidin-biotin affinity system also eliminates the need for harsh elution conditions that may separate the complex and/or damage the target protein or cells. Desthiobiotin technology is ideal for working with native or recombinant proteins that do not express fusion tags or for isolating capture proteins under native conditions, such as when targeting intact cells or cell surface proteins.

Labels with Amine Compounds
Amine-compounds can be coupled to functional groups on proteins and other molecules in a variety of ways. The more common method is to use Cross-links terminal primary amines to carboxyl groups. Carboxyl groups (-COOH) are present on aspartic acid or glutamic acid residues and on the carboxyl termini of polypeptides. When activated withEDC (Product No. 22980), the carboxylate reacts with the amino group (– NH2) group reacts to form an amide bond. Carboxylate molecules and surface materials can be prepared using EDC and Sulfo-NHS (Product No. 24510) Activated for subsequent reactions with primary amines (see NHS-ester chemistry reagent).