Protein Laboratories Rehovot Ltd.
May 2019

Certificate of Analysis & Data Sheet

We are the ONLY company producing leptin antagonists and leptins of farm animals including several fish species.

Pegylated human, mouse, rat and ovine leptins and corresponding leptin antagonists are now available!!!

PLR provides a novel service of pegylation of either existing, or provided or custom-made proteins. All PLR's proteins are carrier free (cf) and can be sold in any requested amount !!!
Mouse super-active leptin antagonist (SMLA) Cat. no. SLAN-1 GENE ID 16846
Description: Recombinant mouse leptin, one polypeptide chain containing 146 amino and additional Ala at N-terminus acids and having a molecular mass of ~ 16 kDa, mLEP was mutated, resulting in D23L/L39A/D40A/F41A mutant that was purified by proprietary chromatographic techniques.  
Source: Escherichia coli.
Lot Number:  
Quantity Shipped:  
Physical Appearance: White lyophilized (freeze-dried) powder. 
Formulation: The mouse super-active leptin antagonist was lyophilized from a concentrated (1 mg/ml) solution with 0.003mM NaHCO3. 
Solubility: It is recommended to reconstitute the lyophilized mouse super-active leptin antagonist in sterile water or sterile 0.4% NaHCO3 adjusted to pH 8-9, not less than 100µg/ml, which can then be further diluted with other aqueous solutions.  
Stability: Lyophilized mouse super-active leptin antagonist although stable at room temperature for several weeks, should be stored desiccated below -20C.
Upon reconstitution of mouse super-active leptin antagonist at > 0.1 mg/ml and up to 2 mg/ml and filter sterilization mouse super-active 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 mouse super-active leptin antagonist is greater than 98.0% 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 five N-terminal amino acids of mouse super-active leptin antagonist was determined and was found to be Ala-Val-Pro-Ile-Gln
Dimers and Aggregates: The purified mouse super-active leptin antagonist (16K) consists of > 95% monomers as determined by gel-filtration chromatography.
Biological Activity: PLR’s mouse super-active leptin antagonist is capable of inhibiting leptin-induced proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. Mouse super-active leptin antagonist also inhibits various leptin effects in several in vitro bioassays. The inhibitory activity of mouse super-active leptin antagonist was increased 14 to 60 fold as measured by various criteria such as binding properties to human leptin binding domain (hLBD) and in vitro and in vivo bioassays as compared to mouse leptin antagonist . 
Endotoxin: The endotoxin content of mouse super-active leptin antagonist is less than 0.02 ng/µg (0.2 EU/µg) of mouse leptin antagonist. 
Protein content: Protein quantization of mouse super-active leptin antagonist was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.200 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 mouse super-active leptin antagonist is furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals. It is for Research Purposes Only – Commercial Use has been Licensed Exclusively to a Third Party. 
Date Shipped: 23.09.2010