| Description : |
Defensins (alpha and beta) are cationic peptides with a broad spectrum of antimicrobial activity that comprise an important arm of the innate immune system. The α-defensins are distinguished from the β-defensins by the pairing of their three disulfide bonds. To date, four human β-defensins have been identified; BD-1, BD-2, BD-3 and BD-4. The β-defensin proteins are expressed as the C-terminal portion of precursors and are released by proteolytic cleavage of a signal sequence. β-defensins contain a six-cysteine motif that forms three intra-molecular disulfide bonds. β-defensins are 3-5 kDa peptides ranging in size from 33-47 amino acid residues. BD-4 is expressed in testis, stomach, uterus, neutrophils, thyroid, lung and kidney. In addition to its direct antimicrobial activities, BD-4 is chemoattractant towards human blood monocytes. |
| Source : |
E. coli |
| Species : |
Human |
| Form : |
Sterile Filtered White lyophilized (freeze-dried) powder. |
| Bio-activity : |
Determined by its ability to chemoattract human monocytes using a concentration range of 0.1-100.0 ng/mL, corresponding to a Specific Activity of ＞1 × 10^4 IU/mg. |
| Molecular Mass : |
Approximately 6.0 KDa, a single non-glycosylated polypeptide chain containing 50 amino acids. |
| Protein Length : |
50 |
| AA Sequence : |
EFELDRICGYGTARCRKKCRSQEYR IGRCPNTYACCLRKWDESLLNRTKP |
| Endotoxin : |
Less than 1 EU/μg of rHuBD-4 as determined by LAL method. |
| Purity : |
>98% by SDS-PAGE and HPLC analyses. |
| Storage : |
This lyophilized preparation is stable at 2-8 centigrade, but should be kept at -20 centigrade for long term storage, preferably desiccated. Upon reconstitution, the preparation is stable for up to one week at 2-8 centigrade. For maximal stability, apportion the reconstituted preparation into working aliquots and store at -20 to -70 centigrade. Avoid repeated freeze/thaw cycles. |
| Storage Buffer : |
Lyophilized from a 0.2 μm filtered concentrated solution in 20mM PB, pH 7.4, 130mM NaCl. |
| Reconstitution : |
We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at < -20C. Further dilutions should be made in appropriate buffered solutions. |
