Leptin Pufferfish Recombinant
Leptin Pufferfish (Takifugu rubripes) Recombinant produced in E.Coli is a single, non-glycosylated, polypeptide chain having a molecular mass of 16 kDa.
Bioactive Leptin Pufferfish (Takifugu rubripes) Recombinant was prepared according to the sequence published by Kurokawa et al. (2005)Peptides 26, 745-750 in two forms: monomer and covalent dimer. MS analysis revealed molecular masses of 15,291 and 30,585 Da, close to the theoretical values of 15,270 and 30,540 Da. CD spectra revealed high similarity to mammalian leptins. Other details of its preparation will be soon published by Yacobovitz et al (in press), General and Comparative Endocrinology.
The Pufferfish Leptin is purified by proprietary chromatographic techniques.
Accession
Amino acid sequence
The sequence of the first five N-terminal amino acids was determined and was found to be Ala-Leu-Pro-Gly-Ala.
Biological Activity
Biological active as evidenced by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. The affinity of human leptin receptors is considerably lower campared to mammalian leptins.
Formulation
The Pufferfish Leptin was lyophilized from a concentrated (0.85mg/ml) solution with 0.003mM NaHCO3.
Physical Appearance
Sterile Filtered White lyophilized (freeze-dried) powder.
Protein content
Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 1.28 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
Purity
Greater than 99.0% as determined by:
(a) Analysis by SEC-HPLC.
(b) Analysis by SDS-PAGE.
Solubility
It is recommended to reconstitute the lyophilized Pufferfish Leptin in sterile 0.4% NaHCO3 pH-9 not less than 100ug/ml, which can then be further diluted to other aqueous solutions.
Source
Stability
Lyophilized Pufferfish Leptin although stable at room temperature for 3 weeks, should be stored desiccated below -18oC. Upon reconstitution Leptin should be stored at 4oC between 2-7 days and for future use below -18oC.
For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please prevent freeze-thaw cycles.
Synonyms
OB Protein, Obesity Protein, OBS, Obesity factor.
