Protein Laboratories Rehovot Ltd.
Rat leptin Cat no. LEP-12 GENE ID 25608
Description:
Recombinant rat leptin, (rLEP)is a single polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular mass of ~ 16 kDa, rLEP was purified by proprietary chromatographic techniques, according to Salomon et al (2006) Protein Expression and Purifcation 47, 128–136.
Source:
E. coli
Physical Appearance:
White lyophilized (freeze-dried) powder.
Formulation:
The recombinant rat leptin was lyophilized from a concentrated (1mg/ml) solution with 0.0045mM NaHCO3.
Solubility:
It is recommended to reconstitute the lyophilized recombinant rat leptin in sterile water or 0.4% NaHCO3 adjusted tp pH 8-9, not less than 100µg/ml. Recombinant rat leptin can then be further diluted to other aqueous solutions, preferably in presence of carrier protein.
Stability:
Short term stability: Lyophilized recombinant rat leptin although stable at room temperature for several weeks, should be stored desiccated below -18C. Upon reconstitution at > 0.1 mg/ml of recombinant rat leptin and up to 2 mg/ml and filter sterilization recombinant rat leptin can be stored at +4C.
Long term stability: The product is tested for purity (gel filtration analysis and SDS-PAGE gel) and for bioactivity each time prior to providing it to customer. Then if stored desiccated below -18C is stable for at least 3 years.
Long term stability: The product is tested for purity (gel filtration analysis and SDS-PAGE gel) and for bioactivity each time prior to providing it to customer. Then if stored desiccated below -18C is stable for at least 3 years.
Purity:
The purity of recombinant rat leptin is greater than 98.0% as determined by:
(a) Gel filtration analysis.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
(c) RP-chromatography
(a) Gel filtration analysis.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.
(c) RP-chromatography
Amino Acid Sequence:
The sequence of the first five N-terminal amino acids of recombinant rat leptin was determined and was found to be Ala-Val-Pro-Ile-His.
Dimers and Aggregates:
The purified recombinant rat leptin (16K) consists of > 99% monomers as determined by gel-filtration chromatography.
Biological Activity:
PLR’s recombinant rat 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:
Less than 0.1 ng/µg (IEU/µg) of recombinant rat leptin
Protein content:
Protein quantitation of recombinant rat leptin was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.20 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:
The recombinant rat leptin is offered by PLR for laboratory research only