Protein Laboratories Rehovot Ltd.
Salamander leptin - Cat no. LEP-13 GENE ID not reported
Description:
Recombinant salamander leptin (Sal-LEP)is a single polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular mass of ~ 16 kD. Recombinant salamander leptin was purified by proprietary chromatographic techniques, similarly to that described previously by Salomon et al (2006) Protein Expression and Purifcation 47, 128–136.
Source:
E. coli
Physical Appearance:
White lyophilized (freeze-dried) powder.
Formulation:
The recombinant salamander leptin was lyophilized from a concentrated (1mg/ml) solution with 0.0045mM NaHCO3.
Solubility:
It is recommended to reconstitute the lyophilized recombinant salamander leptin in sterile water or 0.4% NaHCO3 adjusted tp pH 8-9, not less than 100µg/ml. Recombinant salamander leptin , which can then be further diluted to other aqueous solutions, preferably in presence of carrier protein.
Stability:
Lyophilized recombinant salamander leptin although stable at room temperature for several weeks, should be stored desiccated below -18C. Upon reconstitution of recombinant salamander leptin at > 0.1 mg/ml and up to 2 mg/ml and filter sterilization recombinant salamander leptin can be stored at +4C for at least two weeks.
Purity:
The purity of recombinant salamander leptin is greater than 99.0% 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 ten N-terminal amino acids of recombinant salamander leptin was determined and was found to be Ala-Ile-Met-Val-Asp-Gln-Leu-Arg-Met-Asp.
Dimers and Aggregates:
The purified Sal-LEP (16K) consists of > 99% monomers as determined by gel-filtration chromatography.
Biological Activity:
PLR’s recombinant salamander leptin is fully biologically active as evidenced by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. The activity of recombinant salamander leptin in that test is similar to that of mouse leptin (see Salomon et al (2006) Protein Expression and Purifcation 47, 128–136).
Endotoxin:
Less than 0.05 ng/µg (IEU/µg) of recombinant salamander leptin
Protein content:
Protein quantitation of recombinant salamander leptin was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.104 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 salamander leptin is offered by PLR for laboratory research