Expression and purification of exendin-4, a GLP-1 receptor agonist, in Escherichia coli

• DOI: 10.1016/j.pep.2004.10.014
• Publication Date: 2005-03-22T12:34:32Z
• Authors: Xiaopu Yin; Dongzhi Wei; Lina Yi; Xinyi Tao; Yushu Ma
• Keywords: Blood Glucose; Male; 0301 basic medicine; Base Sequence; Venoms; Recombinant Fusion Proteins; Molecular Sequence Data; Glucagon-Like Peptide-1 Receptor; Rats; 3. Good health; 03 medical and health sciences; Glucose; Gene Expression Regulation; Escherichia coli; Receptors, Glucagon; Animals; Exenatide; Cloning, Molecular; Rats, Wistar; Peptides

Exendin-4 is a 39 amino acid peptide isolated from salivary secretions of Gila monster (Heloderma suspectum). It shows 53% sequence similarity to glucagon-like peptide-1 (GLP-1), which is evaluated for the regulation of plasma glucose in type 2 diabetes. Exendin-4 is a potent and long-acting agonist of GLP-1 receptor. In the present study, the exendin-4 gene obtained by PCR with an enterokinase site at N-terminus and a termination codon at C-terminus was expressed in Escherichia coli strain BL21 (DE3) harboring pET32a(+). The fusion protein was purified by chromatography on Ni-NTA-agarose column. Recombinant exendin-4 was obtained by enterokinase cleavage of the fusion protein and subsequent purification. The yield of recombinant exendin-4 was 3.15mg/10g bacteria. The obtained recombinant exendin-4 shows glucose-lowering action in vivo.