Leptin Antagonist Triple Mutant Human Recombinant, Pegylated
Pegylated Leptin Antagonist Triple Mutant Human Recombinant is a single non-glycosilated polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular weight of 35.6kDa, Leptin was mutated, resulting in L39A/D40A/F41A. 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. Leptin Antagonist Triple Mutant Human Recombinant is Mono-Pegylated with 20kDa PEG and was purified by proprietary chromatographic techniques.
Accession
Biological Activity
Capable of inhibiting leptin-induced proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. Its in vitro activity is 6-8 fold lower than the non-pegylated antagonist but in vivo it has profound weight gain effect in mice (as compared to the non-pegylated antagonist), resulting mainly from increased food intake.
Formulation
The protein was lyophilized from a concentrated (0.65mg/ml) solution with 0.003mM NaHCO3.
Physical Appearance
White lyophilized (freeze-dried) powder.
Protein content
Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.88 as the extinction coefficient for a 0.1% (1mg/ml) solution at pH 8.0. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
Purity
Greater than 98.0% as determined by:
(a) Gel filtration analysis.
(b) Analysis by SDS-PAGE.
Solubility
It is recommended to reconstitute the lyophilized Leptin Antagonist Triple Mutant pegylated Human Recombinant in sterile 0.4% NaHCO3 adjusted to pH 8-9, not less than 100ug/ml, which can then be further diluted to other aqueous solutions.
Source
Stability
Lyophilized Pegylated Leptin Antagonist Triple Mutant Human Recombinant although stable at room temperature for several weeks, should be stored desiccated below -18oC. Upon reconstitution at > 0.1 mg/ml and up to 2mM and filter sterilization Leptin mutant can be stored at 4oC or even room temperature for several weeks making it suitable for long term infusion studies using osmotic pumps. At lower concentration addition of a carrier protein (0.1% HSA or BSA) is suggested. Please prevent freeze-thaw cycles.
