Rational Design of a Carrier Protein for the Production of Recombinant Toxic Peptides in Escherichia coli.
Katia Pane, Lorenzo Durante, Elio Pizzo, Mario Varcamonti, Anna Zanfardino, Valeria Sgambati, Antimo Di Maro, Andrea Carpentieri, Viviana Izzo, Alberto Di Donato, Valeria Cafaro, Eugenio Notomista
Author Information
Katia Pane: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Lorenzo Durante: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Elio Pizzo: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Mario Varcamonti: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Anna Zanfardino: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Valeria Sgambati: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Antimo Di Maro: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Seconda Universit�� di Napoli, Caserta, Italy.
Andrea Carpentieri: Department of Chemical Sciences, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Viviana Izzo: Department of Medicine and Surgery, Universit�� degli Studi di Salerno, Baronissi, Italy.
Alberto Di Donato: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Valeria Cafaro: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Eugenio Notomista: Department of Biology, Universit�� degli Studi di Napoli Federico II, Napoli, Italy.
Commercial uses of bioactive peptides require low cost, effective methods for their production. We developed a new carrier protein for high yield production of recombinant peptides in Escherichia coli very well suited for the production of toxic peptides like antimicrobial peptides. GKY20, a short antimicrobial peptide derived from the C-terminus of human thrombin, was fused to the C-terminus of Onconase, a small ribonuclease (104 amino acids), which efficiently drove the peptide into inclusion bodies with very high expression levels (about 200-250 mg/L). After purification of the fusion protein by immobilized metal ion affinity chromatography, peptide was obtained by chemical cleavage in diluted acetic acid of an acid labile Asp-Pro sequence with more than 95% efficiency. To improve peptide purification, Onconase was mutated to eliminate all acid labile sequences thus reducing the release of unwanted peptides during the acid cleavage. Mutations were chosen to preserve the differential solubility of Onconase as function of pH, which allows its selective precipitation at neutral pH after the cleavage. The improved carrier allowed the production of 15-18 mg of recombinant peptide per liter of culture with 96-98% purity without the need of further chromatographic steps after the acid cleavage. The antimicrobial activity of the recombinant peptide, with an additional proline at the N-terminus, was tested on Gram-negative and Gram-positive strains and was found to be identical to that measured for synthetic GKY20. This finding suggests that N-terminal proline residue does not change the antimicrobial properties of recombinant (P)GKY20. The improved carrier, which does not contain cysteine and methionine residues, Asp-Pro and Asn-Gly sequences, is well suited for the production of peptides using any of the most popular chemical cleavage methods.
References
Biochim Biophys Acta. 2004 Jan 28;1660(1-2):53-65
[PMID: 14757220]
