Leptin is a 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.
Leptin Rat Recombinant produced in E. coli is a single, non-glycosylated, polypeptide chain containing 147 amino acids and having a molecular mass of 16 kDa. The sequence of the first five N-terminal amino acids was determined and was found to be Ala-Val-Pro-Ile-His. The protein was lyophilized from a concentrated (1 mg/ml) solution with 0.0045mM NaHCO3. It is purified by proprietary chromatographic techniques. Biological activity is evidenced by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. Protein quantitation was determined by UV spectroscopy at 280 nm and analysis by RP-HPLC using a calibrated solution of Leptin Rat as a reference standard. It has been determined that Leptin Rat is more than 95% pure by analysis with SEC-HPLC and SDS-PAGE.