Certificate of Analysis & Data Sheet
Recombinant chicken leptin binding domain (chLBD), is one polypeptide chain containing 208 amino acids and an additional Ala at N-terminus acids. It consists of the cytokine binding domain of leptin receptor (amino acids 420-626 of chicken leptin receptor and having a molecular mass of ~ 24.5 kDa, It was purified by proprietary chromatographic techniques (see Niv-Spector et al. Biochemical Journal (2005) 390:475-484.
White lyophilized (freeze-dried) powder or sterile 0.05% solution.
The protein was lyophilized from a concentrated (0.2 to 0.5 mg/ml) solution of Tris-HCl buffer, pH 9.0 with 150 mM NaCl and 10-fold (w/w) excess of glycine. This formulation allows full solubilization by adding water and gentle mixing and fully preserves the binding capacity of chLBD.
It is recommended to reconstitute the lyophilized chLBD in sterile water at pH 8-9, not less than 100µg/ml, which can then be further diluted to other aqueous solutions, preferably in presence of carrier protein.
Lyophilized chLBD should be stored desiccated below -18C. Upon reconstitution at > 0.1 chLBD mg/ml and up to 40.5 mg/ml mM and filter sterilization chLBD can be stored at 4C for several months. Sterile solutions at 0.5 mg/ml or less are stable at +4C for several months.
Greater than 99.0% as determined by:
(a) Gel filtration analysis.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
Amino Acid Sequence:
The sequence of the first six N-terminal amino acids was determined and was found to be Ala-Ile-Asp-Val-Asn-Ile
Dimers and Aggregates:
The purified chLBD (24K) consists of > 95% monomers as determined by gel-filtration chromatography.
PLR’s chLBDL is fully biologically active as evidenced by high affinity binding of mammalian leptins at 1:1 molar ratio.
Less than 0.1 ng/µg (IEU/µg) of chLBD
Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 2.45 as the extinction coefficient for a 0.1% (1mg/ml) solution at pH 9.0. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
This material is offered by PLR for laboratory research