Description:
                    Recombinant protein - human leptin, one polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular mass of  ~ 16 kDa., Human leptin was purified by proprietary chromatographic techniques, see Raver  et al. Gen. Comp. Endocrinol.  (2002).
                Source:
                    Escherichia coli
                Lot Number:
                    Quantity Shipped:
                    Physical Appearance:
                    White lyophilized (freeze-dried) powder.
                Formulation:
                    The recombinant protein was lyophilized from a concentrated (1mg/ml) solution with 0.0045mM NaHCO3.
                Solubility:
                    It is recommended to reconstitute the lyophilized recombinant human leptin 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. 
                Stability:
                    Lyophilized recombinant  human leptin although stable at room temperature for several weeks, should be stored desiccated below -18C. Upon reconstitution at > 0.1 human leptin mg/ml and up to 2 mg and filter sterilization recombinant  human leptin can be stored at +4C or even room temperature for several weeks. At lower concentration addition of a carrier protein (0.1% HSA or BSA) is suggested. Please prevent freeze-thaw cycles.
                Purity:
                    Purity of recombinant human leptin is greater than 95.0% as determined by:
(a) Gel filtration analysis of the recombinant protein.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
                (a) Gel filtration analysis of the recombinant protein.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
Amino Acid Sequence:
                    The sequence of the first five N-terminal amino acids of recombinant human leptin was determined and was found to be Ala-Val-Pro-Ile-Gln
                Dimers and Aggregates:
                    The purified recombinant human leptin (16K) consists of > 93% monomers as determined by gel-filtration chromatography.
                Biological Activity:
                    PLR’s recombinant human leptin is fully biologically active as evidenced by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. 
                Endotoxin:
                    The endotoxin content of recombinant human leptin is less than 0.1 ng/µg (IEU/µg).
                Protein content:
                    Protein quantitation in recombinant human leptin was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.87 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). 
                Usage:
                    Recombinant human leptin is offered by PLR for laboratory research 
                Date Shipped: