| Source: |
Escherichia coli. |
| Molecular Weight: |
Approximately 5.1 kDa, a single non-glycosylated polypeptide chain containing 47 amino acids. |
| AA Sequence: |
GNFLTGLGHR SDHYNCVSSG GQCLYSACPI FTKIQGTCYR GKAKCCK |
| Purity: |
> 98% by SDS-PAGE and HPLC analyses. |
| Biological Activity: |
Fully biologically active when compared to standard. The biological activity determined by a chemotaxis bioassay using CD34+ dendritic cells is in a concentration range of 100.0-1000.0 ng/mL. |
| Physical Appearance: |
Sterile filtered white lyophilized (freeze-dried) powder. |
| Formulation: |
Lyophilized from a 0.2 µm filtered concentrated solution in 20 mM PB, pH7.4, 130 mM NaCl. |
| Endotoxin: |
Less than 1 EU/µg of rHuBD-1, 47a.a. as determined by LAL method. |
| Reconstitution: |
Centrifuge the vial briefly before opening to ensure that the contents settle at the bottom. Reconstitute the vial with sterile distilled water or an aqueous buffer containing 0.1% BSA to achieve a concentration of 0.1-1.0 mg/mL. Divide the resulting stock solution into working aliquots and store them at or below -20°C. For further dilutions, use appropriate buffered solutions. |
| Stability & Storage: |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70°C as supplied.
1 month, 2 to 8°C under sterile conditions after reconstitution.
3 months, -20 to -70°C under sterile conditions after reconstitution. |
| Synonyms: |
Defensin beta1 |
| Background: |
Defensins, including alpha and beta types, are positively charged peptides known for their antimicrobial properties against a range of organisms such as Gram-negative and Gram-positive bacteria, fungi, and viruses with lipid envelopes. These peptides, which are proteins ranging from 2 to 6 kDa, play crucial roles in the body's first line of defense. Mammalian defensins are categorized into alpha, beta, and theta groups based on their size and unique disulfide bond patterns. β-Defensins are characterized by a motif of six cysteines that form three disulfide bonds within the molecule. To date, four human β-defensins have been discovered, and they are found in certain white blood cells and on the surfaces of epithelial tissues. Due to their positive charge, β-defensins can interact with negatively charged microbial membranes, which contain lipopolysaccharides (LPS) and lipoteichoic acid (LTA). They have a particularly strong affinity for their binding sites, surpassing that of calcium and magnesium ions, and can also influence membrane stability. β-Defensin proteins are initially expressed as the C-terminal part of precursor molecules and are activated through the removal of a signal sequence and, in the case of BD-1, a propeptide region. Beta-defensin 1 is implicated in the development of severe sepsis and variations in this defensin are associated with asthma, showing gender-specific patterns. In cases of prostate and kidney cancers, the expression of human BD1 is reduced. |
