Leptin takes an important part in the regulation of energy balance and body weight control.After entering the circulation, Leptin binds LEPRwhich results in the activation of several major signalling pathways. In the hypothalamus Leptin acts as an appetite-regulating factor that induces a decrease in food intake and an increase in energy consumption and also regulates bone mass and secretion of hypothalamo-pituitary-adrenal hormones. In the periphery, increases basal metabolism, regulates pancreatic beta-cell function and insulin secretion and affects innate and adaptive immunity.
Pegylated Leptin N82K Human Recombinant produced in E.Coli is a single non-glycosilated polypeptide chain containing 146 amino acids, an additional Ala at N-terminus and one molecule of PEG 20 kDa at its N-terminus acids and having a molecular weight of 35.6kDa. However due to enlarged hydrodymanic volume it runs on the SDS-PAGE as 48 kDa protein and in gel-filtration on Superdex 200 as over 200 kDa protein. Pegylated Leptin N82K Human Recombinant was purified by proprietary chromatographic techniques.
Lyophilized from a concentrated (0.65mg/ml) solution with 0.003mM NaHCO3 Having 35-40% protein.
It is recommended to reconstitute the lyophilized Pegylated Leptin N82K in sterile water or 0.4% NaHCO3 adjusted to pH 8-9, not less than 100µg/ml, which can then be further diluted to other aqueous solutions.
Lyophilized Pegylated Leptin N82K although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution Pegylated Leptin N82K 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.
Greater than 99.0% as determined by:
(a) Gel filtration analysis.
(b) Analysis by SDS-PAGE.
Biological Activity is < than 0.1% as determined by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. This abolishment of activity results from drastically reduced affinity toward leptin receptor.
Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.870 as the extinction coefficient for a 0.1% (1mg/ml) protein solution at pH 8.0. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).