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Updated: Aug 25, 2026
Comparative Analysis of Human Growth Hormone in Serum Using SPRi, Nano-SPRi and ELISA Assays
Published on: January 7, 2016
[Purification and activity assay of recombinant growth hormone-releasing hormone]
Xiao-hua Wang1, Na Zhang, Juan-hui Zhang
1Department of Biochemistry, Guangzhou Medical College, Guangzhou 510182, China. xh_wang2631@sina.com
Objective:
To express recombinant growth hormone-releasing hormone (GHRH) peptide in E.coli by genetic engineering and examine its biological activity.
Method:
GHRH peptide was purified to homogeneity by means of cell lysis, washing, ethanol precipitation, acid hydrolysis, SP-Sephadex C25 and Sephadex G-25 column chromatographies.
Result:
SDS-PAGE showed that the recombinant plasmid pET-28a /L-ansB-GHRH in E.coli BL21(DE3) expressed the fusion protein under the induction with IPTG. The fusion protein was expressed in the form of inclusion body, accounting for 30% of the total bacterial protein. After the purification procedures, the peptide was purified about 147-fold with a peptide yield of 0.68%. The molecular mass of the peptide was 5 235 Da as determined by electrospray ionization (ESI) mass spectrum, in agreement with the predicted value, and SDS-PAGE presented a single peak in assessment of the purity. Experiment showed that there were significant differences in the growth hormone released by the peptide between the dose groups and the blank control group, and the differences tended to be more obvious with the increase of the doses.
Conclusion:
The recombinant GHRH peptide possesses good biological activities.
