Leptin, Pegylated

Mono-pegylated (with 20 kDa PEG) recombinant rat leptin is an one polypeptide chain containing 146 amino, an additional Ala at N-terminus and one molecule of PEG 20 kDa at its N-terminus, having an expected molecular mass of ~ 35.6 kDa as determined by MS. However due to enlarged hydrodymanic volume it runs on the SDS-PAGE as 48 kDa protein and in gel-filtration on Superdex 200 as over 100 kDa protein. The half-life in circulation of pegylated recombinant rat leptin after SC injection was over 20 hours. Recombinant rat leptin as purified by proprietary chromatographic techniques according to Salomon et al (2006) Protein Expression and Purification 47, 128–136 and then pegylated.

Product Specifications

Synonyms

Lep; ob; obese

NCBI Gene ID

25608

UniProt

P50596

Accession Number

NP_037208

Accession Number mRNA

NM_013076

Reactivity

Rat

Cross Reactivity

Rat

Label

PEG

Sequence

AVPIHKVQDDTKTLIKTIVTRINDISHTQSVSARQRVTGLDFIPGLHPILSLSKMDQTLAVYQQILTSLPSQNVLQIAHDLENLRDLLHLLAFSKSCSLPQTRGLQKPESLDGVLEASLYSTEVVALSRLQGSLQDILQQLDLSPEC

Assay Protocol

It is recommended to reconstitute the lyophilized recombinant rat leptin 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.

Endotoxin

< 0.1 ng/µg of protein (< 1EU/µg)

Purity

> 98.0% as determined by Gel filtration and SDS-PAGE gel.

Bioactivity

Pegylated recombinant rat leptin is capable of stimulating proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor. Its in vitro activity is only slightly lower than the non-pegylated recombinant rat leptin but in vivo it has profound weight reducing effect (as compared to the non-pegylated leptin), resulting mainly from reduced food intake.