Purification of Large Quantities of Biologically Active Recombinant Human Growth Hormone

Document Type: Research Paper

Authors

National Research Center for Genetic Engineering and Biotechnology, P.O. Box: 14155-6343, Tehran, I.R. Iran.

Abstract

Production and purification of human growth hormone using a simple method was studied in two recombinant
Escherichia coli, D7-5 and C27-2 strains. The r-hGH was expressed in the form of inclusion body in a batch
fermentation process and purified to 99% purity using a procedure based on acid precipitation of the host
derived proteins and other impurities. The effect of the pH and host strain on purification of the r-hGH and
efficiency of the procedure were evaluated. It was found that the optimum pH for precipitation of the host
derived proteins was 4.9. The procedure was suitable for r-hGH purification from D7-5 stain but not from the
other strain C27-2. The purity of > 99% and recovery of about 40% were obtained as shown by SDS-PAGE
and Western blot analysis. The purified r-hGH was biologically active as judged by receptor assay with
very low endotoxin content which could be suitable for therapeutic applications. This simple and cost effective
production process could be useful for large scale production of recombinant hGH from specific strains.

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