| Source: |
Escherichia coli |
| Molecular Weight: |
Approximately 35.3 kDa, a single non-glycosylated polypeptide chain containing 321 amino acids. |
| AA Sequence: |
MKDNTVPLKL IALLANGEFH SGEQLGETLG MSRAAINKHI QTLRDWGVDV FTVPGKGYSL PEPIQLLNAK QILGQLDGGS VAVLPVIDST NQYLLDRIGE LKSGDACIAE YQQAGRGRRG RKWFSPFGAN LYLSMFWRLE QGPAAAIGLS LVIGIVMAEV LRKLGADKVR VKWPNDLYLQ DRKLAGILVE LTGKTGDAAQ IVIGAGINMA MRRVEESVVN QGWITLQEAG INLDRNTLAA MLIRELRAAL ELFEQEGLAP YLSRWEKLDN FINRPVKLII GDKEIFGISR GIDKQGALLL EQDGIIKPWM GGEISLRSAE K |
| Purity: |
> 97% by SDS-PAGE analyses. |
| Biological Activity: |
Measured by its ability to generate pyrophosphate from the biotinylation reaction. The pyrophosphate is subsequently hydrolyzed using Recombinant Yeast Inorganic Pyrophosphatase/PPA1 (ryPPA1). The specific activity is > 10.0 pmol/min/μg, as measured under the described conditions. |
| Physical Appearance: |
Sterile colorless liquid. |
| Formulation: |
Supplied as a 0.2 μm filtered solution in 50 mM Tris-HCl, pH8.0, 150 mM NaCl, 1 mM EDTA, 1 mM DTT, 10% glycerol. |
| Endotoxin: |
Less than 0.1 EU/μg of rBirA as determined by LAL method. |
| Stability & Storage: |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.- 6 months from date of receipt, -20 to -70°C as supplied.- 3 months, -20 to -70°C under sterile conditions after opening. |
| Background: |
BirA, the biotin-protein ligase (BPL) of Escherichia coli, is also known as the biotin operon repressor, biotin-[acetyl-CoA-carboxylase] ligase, and biotin-[acetyl-CoA-carboxylase] synthetase. As a member of the group II biotin-protein ligase family, BirA features an N-terminal helix-turn-helix DNA-binding domain, a catalytic core for synthesizing biotinyl 5' adenylate (bio-5'-AMP), and a C-terminal domain involved in DNA binding, dimerization, and catalysis. BirA acts both as a DNA-binding protein that represses the biotin biosynthesis operon and as an enzyme that synthesizes its own corepressor, bio-5'-AMP, a key intermediate in biotinylation. BirA biotinylates the lysine side chain of biotin-accepting proteins and peptides, such as the natural substrate carboxyl carrier protein (BCCP) and Avi Tag fusion proteins. Once biotinylated, these proteins can engage in (strept)avidin-biotin interactions, which are widely used in biochemistry and cell biology for applications like protein capture, immobilization, multimerization, and molecular bridging. |
