Contents
What is FLAG-tag antibody?
The FLAG tag (peptide sequence DYKDDDDK) is a short, hydrophilic protein tag commonly used in conjunction with antibodies in protein pull-downs to study protein–protein interactions. We offer quality antibodies specific to FLAG tag that can be used in a variety of research needs.
Why is there a 3x FLAG-tag?
The increased length of the 3x Flag-tag increases the affinity of the anti-Flag antibody/affinity reagents. 3x Flag-tag is often used in tandem purification and protein purification. As mentioned above, 3x-Flag-tag is longer than 1x Flag-tag and has more charged amino acids.
What are antigen tags?
An epitope tag is a biological structure or sequence, such as a protein or carbohydrate, which acts as an antigen that is recognized by an antibody. Epitope tagging is a technique in which a known epitope is fused to a recombinant protein using genetic engineering.
What is FLAG-tag sequence?
FLAG-tag, or FLAG octapeptide, or FLAG epitope, is a polypeptide protein tag that can be added to a protein using recombinant DNA technology, having the sequence motif DYKDDDDK (where D=aspartic acid, Y=tyrosine, and K=lysine). A FLAG-tag can be used in many different assays that require recognition by an antibody.
What is Flag tagging used for?
Typically the Flag® tag is used for protein purification from mammalian expression systems or general immunostaining and immunoprecipitation assays.
How does Halo tag work?
The HaloTag is a hydrolase, which has a genetically modified active site, which specifically binds the reactive chloroalkane linker and has an increased rate of ligand binding. This intermediate would then be hydrolyzed by an amino acid residue within the wild-type hydrolase.
What is myc DDK tag?
A myc tag is a polypeptide protein tag derived from the c-myc gene product that can be added to a protein using recombinant DNA technology. It can be used for affinity chromatography, then used to separate recombinant, overexpressed protein from wild type protein expressed by the host organism.
Why is SDS used in Western blotting?
SDS is generally used as a buffer (as well as in the gel) in order to give all proteins present a uniform negative charge, since proteins can be positively, negatively, or neutrally charged. The gel electrophoresis step is included in western blot analysis to resolve the issue of the cross-reactivity of antibodies.
What antigen means?
An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune system does not recognize the substance, and is trying to fight it off. An antigen may be a substance from the environment, such as chemicals, bacteria, viruses, or pollen.
What is T7 tag?
The T7 tag is an 11 amino acid peptide encoded in the leader sequence of T7 bacteriophage gene10. This gene encodes a T7 major capsid protein whose function is not clear. Monoclonal antibodies specific for T7 tag are an important tool for studying expression of recombinant T7-tagged proteins.
What is an anti HA antibody?
Anti-HA is produced in rabbit using a synthetic peptide corresponding to amino acid residues of the human Influenza hemagglutinin (HA), conjugated to KLH. The antibody is affinity-purified on the immobilized immunizing peptide. Anti-HA antibody is specific for N- or C-terminal HA-tagged fusion proteins.
Do antibodies have epitopes?
An epitope, also known as antigenic determinant, is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells. The epitope is the specific piece of the antigen to which an antibody binds.
How can a 3x FLAG peptide be detected?
In general, small tags can be detected with specific monoclonal antibodies. To improve the detection of the FLAG tag the 3x FLAG system has been developed. This threetandem FLAG epitope is hydrophilic, 22-amino-acids long and can detect up to 10 fmol of expressed fusion protein.
How is a FLAG tag added to a protein?
FLAG-tag From Wikipedia, the free encyclopedia FLAG-tag, or FLAG octapeptide, or FLAG epitope, is a polypeptide protein tag that can be added to a protein using recombinant DNA technology, having the sequence motif DYKDDDDK (where D= aspartic acid, Y= tyrosine, and K= lysine).
Which is better for Western blotting 3x flag or 1x flag?
For simple western blotting 1x Flag generally works well. For protein purification or IP on M2-agarose, people use 3X Flag and elute with Flag peptides. Because purifications and IPs are done under native conditions, whereas western are done with denatured proteins, the structure and position of the epitope tag can make a difference for IPs.
Is the tyrosine residue in the FLAG tag sulfated?
However, other available antibodies (e.g., M2) are position-insensitive. The tyrosine residue in the FLAG-tag can be sulfated, which can affect antibody recognition of the FLAG epitope. The FLAG-tag can be used in conjunction with other affinity tags, for example a polyhistidine tag ( His-tag ), HA-tag or myc-tag .