Rapid and efficient production of cecropin A antibacterial peptide in Escherichia coli by fusion with a self-aggregating protein

Table 1 Summary of the expression and purification schemes in the three different systems

Expression systems	AT-HIS expression system	CF expression system	SA-ELK16 expression system
Required steps	Step 1: Expression of fusion protein CeA-Mxe-PT-His₆	Step 1: Expression of antibacterial peptide His₆-CeA	Step 1: Expression of fusion protein CeA-Mxe-ELK16
	Step 2: Cell disruption and supernatant collection	Step 2: Ni²⁺ affinity chromatography	Step 2: Cell disruption and acquisition of protein aggregates
	Step 3: Ni²⁺ affinity chromatography		Step 3: Intein-mediated cleavage
	Step 4: Intein-mediated cleavage		Step 4: acetic acid treatment and collection of CeA peptide.
	Step 5: The second Ni²⁺ affinity chromatography
Time consuming	5 days	2 days	2 days
Final yield of peptide production (μg/mg wet cell pellet) ^a	0.41	0.93 ^b	6.20
Purity of bio-produced Cecropin A peptide (%)	92.1	90.4	99.8

^aYield of cecropin A peptide after intein-mediated cleavage in LB culture: 2.87 ± 0.62 mg/ml wet cell weight in the SA-ELK16 system and 1.48 ± 0.48 mg/ml wet cell weight in the AT-HIS system, estimated with the densitometric analysis software Gel-Pro Analyzer or BCA Protein Assay Kit
^bYield of CeA peptide in CF system, 0.93 μg/ml of reaction mixture

ISSN: 1472-6750