Synonyms       OB Protein, Obesity Protein, OBS, Obesity factor, Leptin. 

Introduction      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. 

Description Leptin Salamander Recombinant produced in E.Coli is a single, non-glycosylated, polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular mass of 16kDa. The Salamander Leptin is purified by proprietary chromatographic techniques. 

Source       Escherichia Coli. 

Physical Appearance      Sterile Filtered White lyophilized (freeze-dried) powder. 

Formulation       The Salamander Leptin was lyophilized from a concentrated (1mg/ml) solution with 0.0045mM NaHCO3. 

Solubility       It is recommended to reconstitute the lyophilized Salamander Leptin in sterile 0.4% NaHCO3 pH-9 not less than 100µg/ml, which can then be further diluted to other aqueous solutions. 

Stability         Lyophilized Salamander Leptin although stable at room temperature for 3 weeks, should be stored desiccated below -18C. Upon reconstitution Leptin should be stored at 4C between 2-7 days and for future use below -18C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Please prevent freeze-thaw cycles. 

Purity       Greater than 99.0% as determined by:

(a) Analysis by Gel-Filtration.

(b) Analysis by SDS-PAGE. 

Amino acid sequence       The sequence of the ten N-terminal amino acids was determined and was found to be Ala-Ile-Met-Val-Asp-Gln-Leu-Arg-Met-Asp. 

Biological Activity By inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. Its activity in that test is similar to that of mouse leptin (see Salomon et al (2006) Protein Expression and Purifcation 47, 128–136). 

Protein content       Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.104 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics). 

Usage       CHI's products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.