Abstract
Purpose: Recombinant human endostatin (rhEs) is an angiogenesis inhibitor which is used
as a specific drug in the treatment of non-small-cell lung cancer.
In the current research, we developed an efficient method for expressing
soluble form of the rhEs protein in the periplasmic space of Escherichia
coli via fusing with pelB signal peptide.
Methods: The human
endostatin (hEs) gene was
amplified using synthetic (hEs) gene as a template;
then, cloned and expressed under T7 lac promoter. IPTG
was used as an inducer for rhEs expression.
Next, the osmotic shock was used to extraction
of protein from the periplasmic space. The presence
of rhEs in the periplasmic space was approved by SDS-PAGE and Western blotting.
Results: The
results show the applicability of pelB
fusion protein system usage for secreting rhEs in the periplasm of E. coli in the laboratory scale. The rhEs represents
approximately 35 % (0.83mg/l) of the total cell protein.
Conclusion: The present study apparently is the first
report of codon-optimized rhEs expression as a fusion with pelB signal peptide.
The results presented the successful secretion of soluble rhEs to the periplasmic
space.