Recombinant Human Leptin (OB)
Leptin is a 16 kDa(146 amino acid residues), non-glycosylated protein hormone involved in regulating body weight, metabolism and reproductive function. It is encoded by the obese (ob) gene and expressed predominantly by adipocytes consistent with the fact that body weight is sensed mainly as the total mass of fat in the body. Leptin is also secreted by cells in the epithelium of the stomach and in the placenta in smaller amounts. Leptin receptors are highly expressed in areas of the hypothalamus that are known to be important in regulating body weight, as well as in T lymphocytes and vascular endothelial cells.
Other Sizes
| BX1102-S: | 2 mg |
| BX1102-L: | 5 mg |
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Custom size is also available upon request.
Specifications
| Lot number: | On label |
| Formulation: | Lyophilized powder lyophilized from a volatile buffer (50 mM NH4HCO3 , pH 8.0). |
| Preservative: | None |
| Molecular Weight: | 16 kD |
| Purity: | >97% on 15% SDS-PAGE |
| Source: | Recombinant mature protein expressed in E. coli (189aa) |
| Sterility: | 0.2 um membrane filtered and packaged aseptically |
| ED50: | ND |
| Endotoxin: | ≤0.1 EU/ug protein |
| QC test: | SDS-PAGE, Native PAGE |
Note: Endotoxin Unit (EU) is determined by Limulus Amebocyte Lysate (LAL) assay.
Reconstitution and use
Reconstitute the contents of the vial using sterile phosphate-buffered saline (PBS) to a concentration no less than 100 ug/ml and aliquot for future use. (If the initial rehydration is too diluting, activity may be lost due to the non-specific adsorption to the container). The solution can then be further diluted to a working stock solution. Bovine serum albumin can be added to the working solution to protect TNF-a from loss at low concentrations.
If the product is going to be used for applications requiring absolute asepsis (e.g. cell culture), it's best to filter-sterilize the solution using a sterile and non-pyrogenic 0.2um membrane before use.
Storage and stability
Upon receiving, store the product at -20oC. After reconstitution, store the working aliquots at 2-8oC for no more than 3 months. For extended storage, aliquot the rehydrated solution (≥100 ug/ml) and freeze at -70oC or -20oC. Avoid repeated freezing and thawing. More dilute solutions stored at -20oC will lose activity faster.
Amino Acid Sequence
MVPIQKVQDD TKTLIKTIVT RINDISHTQS VSSKQKVTGL DFIPGLHPIL TLSKMDQTLA VYQQILTSMP SRNVIQISND LENLRDLLHV LAFSKSCHLP WASGLETLDS LGGVLEASGY STEVVALSRL QGSLQDMLWQ LDLSPGC
SDS-PAGE gel image
Recombinant human leptin (25 ug) was resolved on a 12% SDS-PAGE, with (R) or without 2-mercapto-ethanol, and stained with Coomassie Blue.
