construction of recombinant plasmids for periplasmic expression of human growth hormone in escherichia coli under t7 and lac promoters

Authors

a. zomorodipour

abstract

in order to study the periplasmic expression of human growth hormone (hgh) in escherichia coli, the related cdna was inserted in two expression plasmids carrying pelb signal peptide, one with lac bacterial promoter and the other with a bacteriophage t7-based promoter. the recombinant plasmids were moved to tg1 and bl21 strains of e. coli, respectively. to induce the expression systems, iptg and its natural analog, lactose, were examined. results show the over-expression of recombinant hgh (rhgh) in the t7-based system which is much higher than that of the lac-regulated system. in both systems, a fraction of the hgh, produced by recombinant bacteria, remains in the cytoplasm as pre-protein and the rest is transferred to the periplasmic space as mature protein. any decline in the expression level did not lead to a complete processing and transport of mature hgh to the periplasmic space of the bacteria. it is suggested that, for an efficient expression of rhgh in the periplasmic spaceof e. coli, a combined approach including application of a suitable signal peptide, solubility of the over-expressed protein in cytoplasm in addition to the optimization of the bacterial growth and inducing conditions should be considered.

Upgrade to premium to download articles

Sign up to access the full text

Already have an account?login

similar resources

CONSTRUCTION OF RECOMBINANT PLASMIDS FOR PERIPLASMIC EXPRESSION OF HUMAN GROWTH HORMONE IN ESCHERICHIA COLI UNDER T7 AND LAC PROMOTERS

In order to study the periplasmic expression of human growth hormone (hGH) in Escherichia coli, the related cDNA was inserted in two expression plasmids carrying pelB signal peptide, one with lac bacterial promoter and the other with a bacteriophage T7-based promoter. The recombinant plasmids were moved to TG1 and BL21 strains of E. coli, respectively. To induce the expression systems, IPTG and...

full text

Overexpression of Recombinant Human Beta Interferon (rhINF-β) in Periplasmic Space of Escherichia coli

Human Interferon β (INF-β) is a member of cytokines family which different studies have shown its immunomodulatory and antiviral activities. In this study an expression vector was designed and constructed for expression of human INF-β-1b either in shake flasks and bench top bioreactor. The designed vector was constructed based upon pET-25b(+) with T7 promoter. Recombinant human beta interferon ...

full text

Overexpression of Recombinant Human Beta Interferon (rhINF-β) in Periplasmic Space of Escherichia coli

Human Interferon β (INF-β) is a member of cytokines family which different studies have shown its immunomodulatory and antiviral activities. In this study an expression vector was designed and constructed for expression of human INF-β-1b either in shake flasks and bench top bioreactor. The designed vector was constructed based upon pET-25b(+) with T7 promoter. Recombinant human beta interferon ...

full text

Periplasmic secretion of human growth hormone by Escherichia coli.

The gene coding for human growth hormone (hGH) was fused to the coding sequence for the signal peptide of a secreted Escherichia coli protein. STII heat-stable enterotoxin. This hybrid gene was expressed in E. coli. The signal peptide is properly processed and hGH is secreted in to the periplasmic space. In E. coli, some of the material made is proteolytically clipped or deamidated. The effect ...

full text

My Resources

Save resource for easier access later


Journal title:
journal of sciences, islamic republic of iran

Publisher: university of tehran

ISSN 1016-1104

volume 14

issue 4 2003

Hosted on Doprax cloud platform doprax.com

copyright © 2015-2023