Description:
Recombinant ovine leptin, one polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular mass of ~ 16 kDa, oLEP was mutated, resulting in L39A/D40A/F41A mutant was purified by proprietary chromatographic techniques. Preparation of recombinant leptin antagonists was recently published - Niv-Spector et al, Biochem. J 291;221-230 (2005).
Source:
Escherichia coli.
Lot Number:
Quantity Shipped:
Physical Appearance:
White lyophilized (freeze-dried) powder.
Formulation:
The recombinant leptin antagonist was lyophilized from a concentrated (1mg/ml) solution with 0.0045mM NaHCO3.
Solubility:
It is recommended to reconstitute the lyophilized recombinant leptin antagonist 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 ovine recombinant leptin antagonist although stable at room temperature for several weeks, should be stored desiccated below -18C. Upon reconstitution of ovine recombinant leptin antagonist at > 0.1 mg/ml and up to 2 mg and filter sterilization ovine recombinant leptin antagonist can be stored at +4C 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.
Purity:
The purity of ovine recombinant leptin antagonist is greater than 98.0% as determined by:
(a) Gel filtration analysis.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
(a) Gel filtration analysis.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
Amino Acid Sequence:
The sequence of the first five N-terminal amino acids of ovine recombinant leptin antagonist was determined and was found to be Ala-Val-Pro-Ile-Arg
Dimers and Aggregates:
The purified ovine recombinant leptin antagonist (16K) consists of > 95% monomers as determined by gel-filtration chromatography.
Biological Activity:
PLR’s ovine recombinant leptin antagonist is capable of inhibiting leptin-induced proliferation of BAF/3 cells stably transfected with the long form of ovine leptin receptor. It also inhibits various leptin effects in several in vitro bioassays.
Endotoxin:
The endotoxin content of ovine recombinant leptin antagonist is less than 0.1 ng/µg (IEU/µg) of ovine leptin antagonist.
Protein content:
Protein quantitation of ovine recombinant leptin antagonist was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.21 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:
PLR's ovine recombinant leptin antagonist is furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives, local application or household chemicals. It is for Research Purposes Only – Commercial Use has been Licensed Exclusively to a Third Party.
Date Shipped: